&EPA
United States
Environmental Protection
Agency
EPA 620/R-08/001 | June 2008 | www.epa.gov/ord
Clean Air Research
Multi-Year Plan
2008-2012
June 2008
Office of Research and Development
-------
United States
Environmental Protection
Agency
Clean Air Research Multi-Year Plan
2008-2012
June 2008
U.S. Environmental Protection Agency
Office of Research and Development
Research Triangle Park, NC 27711
-------
Administrative Note
The Office of Research and Development's (ORD) Multi-Year Plans (MYPs) describe what
research ORD proposes to accomplish over the next 5-10 years in a variety of areas. The
MYPs serve three principal purposes: to describe where the research programs are going, to
present the significant outputs of the research, and to communicate the research plans within
ORD and with stakeholders and clients. Multi-year planning permits ORD to consider the
strategic directions of the Agency and how research can evolve to best contribute to the
Agency's mission of protecting health and the environment.
MYPs are intended to be "living documents." ORD will update MYPs on a regular basis to
reflect the current state of the science, resource availability, and Agency priorities. This MYP
was reviewed by ORD's Science Council in October 2007.
11
-------
Contributors
Writing Team
Dan Costa, National Program Director
Stacey Katz, National Center for Environmental Research (NCER)
David Kryak, National Exposure Research Laboratory (NERL)
Douglas McKinney, National Risk Management Research Laboratory (NRMRL)
Andy Miller, NRMRL
Gail Robarge, NCER
Bill Russo, National Health and Environmental Effects Laboratory (NHEERL)
Laurel Schultz, Office of Research and Development
Contributors
Barbara Glenn, NCER
Joe Jarvis, Office of Resources Administration and Management
Carlos Nunez, NRMRL
Russell Owen, NHEERL
Jim Vickery, NERL
Darrell Winner, NCER
Reviewers
Allen Basala, Office of Air Quality Planning and Standards (OAQPS)
Rich Cook, Office of Transportation and Air Quality (OTAQ)
John Girman, Office of Radiation and Indoor Air (ORIA)
Beth Hassett-Sipple, OAQPS
Marion Hoyer, OTAQ
Scott Jenkins, OAQPS
Laura Kolb, ORIA
Phil Lorang, OAQPS
Bill Lovely, Region 1
Joann Rice, OAQPS
David Risley, Office of Atmospheric Programs (OAP)
Linda Sheldon, NERL
John Vandenberg, National Center for Environmental Assessment (NCEA)
Other Research Coordination Team members
Monica Alvarez, Office of Science Policy (OSP)
Andrea Cherepy, Office of Program Management Operations (OPMO)
Robert Fegley, OSP
Doug Grano, OAQPS
Richard Haeuber, OAP
Becky Higgins, OPMO
Bryan Hubbell, OAQPS
William Johnson, OAQPS
Carl Mazza, Office of Air and Radiation
Ken Mitchell, Region 4
in
-------
Michael Morton, Region 6
Solomon Pollard, Region 4
Rich Scheffe, OAQPS
Mohamed Serageldin, OAQPS
Chon Shoaf, NCEA
Marybeth Smuts, Region 1
IV
-------
Table of Contents
List of Acronyms and Abbreviations vi
I. INTRODUCTION 1
A. Program Purpose 1
B. Program Design 3
1. Major Policy Challenges and Science Needs 5
2. External Program Reviews 11
3. ORD Laboratories and Centers 13
4. Client-Partners for Air Research 14
5. ORD Partners in Research 14
6. Resources 16
II. THE CLEAN AIR RESEARCH MULTI-YEAR PLAN 16
A. Changes from the Previous MYP 16
B. Long-Term Goals 17
C. LTGs in Relation to Air Program Needs, Priority Science Questions and APGs 17
D. Linking Clean Air Research with other ORD Programs 33
E. Performance Assessment Rating Tool Long-Term Goals and Measures 35
III. CONCLUSIONS 37
Appendix A: Recent Program Accomplishments 39
-------
List of Acronyms and Abbreviations
APG - Annual Performance Goal
APM - Annual Performance Measure
BOSC - Board of Scientific Counselors
CAA - Clean Air Act
CAIR - Clean Air Interstate Rule
CAMR- Clean Air Mercury Rule
CAVR- Clean Air Visibility Rule
CENR - Committee on Environment and Natural Resources
CMAQ - Community Multiscale Air Quality
CRC - Coordinating Research Council
DOE - Department of Energy
EPRI - Electric Power Research Institute
FACA - Federal Advisory Committee Act
HAP - hazardous air pollutant
HEI - Health Effects Institute
HHRA - Human Health Risk Assessment
HHRP - Human Health Research Program
IRIS - Integrated Risk Information System
L/C - Laboratory/Center
LTG - Long-term Goal
MACT - Maximum Achievable Control Technology
MYP - Multi-year Plan
NAAQS - National Ambient Air Quality Standard
NAS - National Academy of Sciences
NATA - National Air Toxics Assessment
NCEA - National Center for Environmental Assessment
NCER - National Center for Environmental Research
NHLBI - National Heart, Lung, and Blood Institute
NIEHS -National Institute of Environmental Health Sciences
NOx - nitrogen oxides
NRC - National Research Council
OPA - Office of Atmospheric Programs
OAQPS - Office of Air Quality Planning and Standards
OAR - Office of Air and Radiation
OMB - Office of Management and Budget
ORD - Office of Research and Development
OTAQ - Office of Transportation and Air Quality
PART - Performance Assessment Rating Tool
PM - particulate matter
RCT - Research Coordination Team
RFA - Request for Application
RPOs - Regional Planning Organizations
SERDP - Strategic Environmental Research and Development
SIP - State Implementation Plan
SOx - sulfur oxides
VI
-------
THIS PAGE IS LEFT BLANK INTENTIONALLY
vn
-------
I. INTRODUCTION
A. Program Purpose
Air pollution continues to have adverse impacts on the human and environmental health of the
United States, despite clear evidence that overall air quality has improved.l The EPA Strategic
Plan 2006-2011 (Strategic Plan) identifies Clean Air and Global Climate Change (Goal 1) as a
primary goal for environmental protection with its first objective being Healthier Outdoor Air,
and its second objective, Healthier Indoor Air.2 EPA's Strategic Plan Goal 1 also establishes an
objective to provide and apply sound science to support the goal of clean air by conducting
leading-edge research to support regulatory decisionmaking. This research provides the scientific
foundation to develop regulations and advanced tools and models to implement air quality
standards and controls by the States, EPA Regions, and tribes. At the same time, the research
program strives to develop better ways to track progress in achieving health and environmental
improvements under this goal. The Clean Air Research program targets this first objective by
providing the science needed to review, attain, and maintain ambient air quality standards
required to protect public health. This research, together with the rest of the Clean Air Research
program, has the added benefit of addressing risk reduction from a number of toxic air
pollutants, and increases in the number of Americans experiencing healthier indoor air in homes,
schools, and office buildings. Although the Clean Air Research program considers within its
overall goal the reduction of air pollution impacts on ecosystems and visibility, research specific
to the protection of public health remains the top priority of the Office of Research and
Development's (ORD's) clients.
In 2007, the White House Office of Management and Budget (OMB) found that reductions in
hospitalizations and emergency room visits, lost work and school days, and premature deaths
account for the greatest expected benefits of air pollution regulation. Between 1996 and 2006,
OMB attributed an annual savings of $63 to $430 billion to the development and implementation
of air pollution regulations-most notably from control of particulate matter (PM).3 The benefits
of air pollution regulation accounted for -94% of estimated benefits from all EPA regulations
and -63 to 88% of estimated benefits across all federal agencies, while costing an estimated $25
to $28 billion to implement over this same period.
ORD has developed multi-year plans (MYPs) in a number of program areas to describe the
research ORD proposes to accomplish over the next several years. The MYP is intended to
provide a vision of the research program and the programmatic rationale for its intended
directions. In addition, the MYP provides an up-to-date, structured listing and description of the
significant expected outputs from its research, which serves to communicate across ORD and
1 These data are summarized in the Air Quality Criteria Documents for PM (10/29/04 -
http://cfpub.epa.gov/ncea/cfm/recordisplav.cfm?deid=87903) and Ozone and Related Photochemical Air Pollutants (01/31/05 -
http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid= 114523). Risks from Hazardous Air Pollutants possess even greater
uncertainty (http://www.epa.gov/ttn/atw/nata/natsa4.html). Additional information on trends in air quality and emissions can be
found at the Office of Air and Radiation site: http://www.epa.gov/air/airtrends.
2 EPA Strategic Plan 2006-2011 (Goal 1: Clean Air and Global Change; Objectives 1.1, 1.2, 1.6; p. 11) -
http://www.epa.gov/ocfo/plan/2006/goal_l.pdf
Draft 2007 Report to Congress on the Costs and Benefits of Federal Regulations - Tables 1.1 and 1.2; pp. 7-8; -
http://www.whitehouse.gov/omb/inforeg/2007_cb/2007_draft_cb_report.pdf
-------
with stakeholders, clients, and reviewers. Multi-year planning permits ORD to consider the
strategic directions of the EPA and how research can evolve to best meet the EPA's mission of
protecting public health and the environment.
This MYP supports the goal of Clean Air by defining the research needed to answer key
questions regarding the development and implementation of National Ambient Air Quality
Standards (NAAQS)-primarily targeting PM and ozone as high-risk pollutants. In addition, it
also supports, although secondarily, the goals of managing hazardous air pollutants (HAPs)This
MYP includes a major shift in the Clean Air Research program by combining several program
areas that previously had targeted air pollutants individually (e.g., PM, ozone, HAPs)Although it
is essential to provide support for the various NAAQS pollutants that continue to be regulated
individually, a multipollutant research program better reflects the complexity of real-world air
pollution problems and parallels the evolving scientific and regulatory context. The Clean Air
Research program uses the science-based framework, shown in Figure 1, developed by the
National Academy of Sciences' (NAS's) National Research Council (NRC) in 1998 and
modified by the Air Quality Research Subcommittee (AQRS) of the Committee on Environment
and Natural Resources (CENR) in 2007 to identify those pollutants and sources responsible for
the greatest health risk. Critical components of this research are used to develop an
understanding of how pollutants from sources impact ambient concentrations, how these
concentrations relate to exposures, and, in turn, how exposures relate to health outcomes. This
information provides the fundamental linkages for evaluating health impacts, ascertaining which
sources are most egregious in terms of health risk, and in developing effective mitigation
strategies.
Paradigm for Federal Research on Particulate Matter
RISK MANAGEMENT
EXPOSURE
(Source to Receptor)
RISK ASSESSMENT
(Receptor Response)
Biological
Effects
Adverse
Health Effects
\
Health
Assessment
Legal Considerations
Transport and
Transformation
Public Health
Considerations
Exposure - Do* - Res
Relatioiships
Characterization
Risk
Management
Environmental
Concentration
Economic, >^
& Political
Exposure
Assessment
' '' / "\
* { Evaluation of Exposure and Public Health Improvement W-
ACCOUNTABILITY
Figure 1. Paradigm for Federal Research on Particulate Matter4
From http://www.esrl.noaa.gov/csd/AQRS/reports/pmplan.pdf
-------
The transition to an air research program emphasizing both "source to health outcomes" and
multipollutant approaches reflects the recommendations of EPA advisory boards and the
reorganization of the Office of Air Quality Planning and Standards (OAQPS). The NRC, over
the period of 1998 to 2004, developed for EPA, under a Congressional directive, a series of
documents to guide PM and copollutant research. The last report (April 2004) recommends that
EPA adopt a broader multipollutant research perspective, and increase its efforts to link observed
heath outcomes with specific components and sources of PM.5 This approach was endorsed by
EPA's Board of Scientific Counselors (BOSC) in 2005.6 Likewise, following the lead of a
related NRC report entitled "Air Quality Management in the United States," the Clean Air Act
Advisory Committee (CAAAC)7, consisting of representatives from EPA, State and local
agencies, tribes, industry, and environmental and research organizations, also strongly endorsed
a broad air quality, rather than a pollutant-by-pollutant, approach for more effective air quality
management. Finally, in keeping with the CAAAC recommendation, OAQPS, which is a main
client of the ORD Clean Air Research program, has reorganized away from pollutant-specific
groupings to a more sector-based structure to improve HAPs control and air quality assessment.
Based on the combination of guidance from external advisory boards and the evolving needs of
our clients, the focus of the Clean Air Research program was adjusted to support this more
realistic, yet complex air pollution approach.
B. Program Design
In support of the broader EPA and ORD Strategic Plans, this MYP provides a focused strategy
for Clean Air Research for ORD laboratories and centers and identifies linkages to other relevant
MYPs such as the Human Health Research program (HHRP) and the Human Health Risk
Assessment (HHRA) program. It provides a "roadmap" built on the progress that ORD has made
since 1998 when PM rose to prominence via Presidential and Congressional mandate.8 The
roadmap, however, is intended to be sufficiently flexible to facilitate responsiveness to
unforeseen changes and developments in the complex scientific landscape ahead.
The development of this roadmap is reflected in the diagram illustrated in Figure 2, which
outlines the progression of scientific research from the recognition of need to use the new
information with its impact on human and environmental outcomes.
The fundamental problem-driven question that drives the Clean Air Research program is "How
can we reduce health risks associated with exposure to air pollution?" The ability to adequately
address this overarching question requires that ORD maintain and continue to develop its core
research capabilities across a diverse range of scientific disciplines, including: cell, animal, and
human toxicology; epidemiology and biostatistics; human exposure; source emissions
characterization and analysis; source apportionment; ambient measurements; atmospheric
chemistry; air quality modeling and forecasting; and technology evaluation and assessment.
National Academy of Sciences (NAS) National Research Council (NRC): Research Priorities for Airborne Particulate Matter:
http://books.nap.edu/catalog.php?record_id=10957.
6 BOSC Report on the PM-Ozone Program Review: April 2005 - http://www.epa.gov/osp/bosc/pdf/pm0508rpt.pdf.
7 http://www.nap.edu/catalog/10728.html.
8 "Particulate Matter Research Program: Five Years of Progress" released in February, 2004, which summarized the
achievements of EPA's research program in advancing our understanding of both health/exposure and air quality issues through
early 2003 (http://www.epa.gov/pmresearch/pm_research_accomplishments/'l.
-------
Develop
Lab/Center
Operating
^ Plans
+
RES
^ PUBLIC ATlt
EPA's Annual
Decisions about
Budgets and
Resources * 4
Planning and Budgeting
Identify Performance |
^ Goals for Each Topic
RESEARCI
BIBLIOMETRIC A
EARCH OUTPUT METRICS:
WS, BIBLIOMETRIC ANALYSIS, APMs, APGs
\
\
Progress in
1 Research
Activities |
Funded for
Each Topic
\
Research
Outputs: |
New Research
Knowledge and
Applicatons
entfy Research
Themes B
i IMPACT METRICS:
NALYSIS, APGS, CLIENT USE
\
\
\
\
EPA/Client
1 | Actions
Research Contributes
to Changes in
Knowledge, Skills, and
Decisions
Identify Knowledge Gaps
1 and Research Questions
'**.
EPA Strategic Goal 1 : Protect and
improve the air so it is healthy to
breathe, and risks to human health
and the environment are reduced.
Reduce greenhouse gas intensity by
enhancing partnerships with
businesses and other sectors.
- *"
a £ 1 EPA Actions
Lead to
Improved Air
Quality
\
METRICS FOR
ENVIRONMENTAL
Research, Application, Action, and Results RESULTS
k. /NP/r-AT"R* rip f~"NP/T/"N «,
CHANGE IN CONDITION
Figure 2. Logic Diagram.
These fundamental capabilities are leveraged within the Clean Air Research program and ORD
to maximize project output, science relevance, and resource efficiencies. The goal is to not only
address research questions of immediate importance to reducing air pollution health risks, but
provide the foundation to anticipate and solve future environmental problems.
ORD structures its research agenda to address its clients' needs and the research priorities
identified by the science community. As detailed below in the research plan, key long-term
science goals (LTGs) are established from which critical questions are fashioned to frame the
research over the next several (~5) years. Researchers work with their Laboratory/Center (L/C)
representatives to develop annual performance goals (APGs) that collectively achieve the LTGs
over a period of years. More specific annual performance measures (APMs) collectively provide
the comprehensive body of research to support a given APG. As such, the APMs are the science
building blocks that describe the products expected from the relevant scientific research. Thus, to
reflect the overall program investment and to be effective, this MYP places considerable
emphasis on the planning and the integration of research. Importantly, however, some latitude
for novel and creative initiative is built within the program in an effort to link fundamental
science and breakthroughs with known, pressing air pollution problems.
The plan and its science are reviewed at several stages along its development. A Research
Coordination Team (RCT) comprised of senior scientists and managers from each ORD
Laboratory and Center and multiple representatives from interested client Offices and Regions
reviews the priority structure and overall framework of the various LTGs and APGs. The RCT
also reviews the APMs and the descriptors that accompany them to gain insight into the plan and
its anticipated products. Indeed, the APMs in many cases arise from discussions with members
-------
of the RCT in the early stages of MYP development.
To ensure the utility and recognition of delivered products, each APG has a designated ORD lead
and a client (partner)-advocate who communicate throughout the life of the. This regular
discourse is designed to ensure progress, the communication of findings, and appropriate
distribution of the anticipated product to the client/partner office and broader community.
Finally, the MYP has been reviewed by ORD's Science Council and an external review panel
(i.e., BOSC) for scientific soundness. However, it is important to appreciate that the MYP is
regarded as a "living document" meant to serve as a roadmap with important science milestones,
while maintaining sufficient fluidity to absorb the newest findings and the ability to evolve from
there. Naturally, as workforce and fiscal resources are increasingly constrained, the final MYP
reflects primarily the highest research priorities, with the intent of achieving the most effective
program possible within ORD's direct and leveraged resources. As described below, the program
design and implementation considers major policy challenges, external program reviews, the
capabilities of the ORD laboratories and centers, partner needs, ORD partner capabilities, and all
available resources.
1. Major Policy Challenges and Science Needs
The Office of Air and Radiation (OAR) is responsible for multiple policy areas regarding the
"air" environment and, as such, comprises several offices with specific, yet wide-ranging
functions: OAQPS-ambient air regulation and rule implementation; the Office of Transportation
and Air Quality (OTAQ)-fuels and mobile sources; the Office of Radiation and Indoor Air
(ORIA)-indoor environments; the Office of Atmospheric Programs (OAP)-air quality through
market systems, ecosystem protection, and climate; and the Office of Policy Analysis and
Review (OPAR)-policy and rule analysis. Facing an array of complex policy decisions that rely
on the latest and most robust science, OAR is a major user of clean air research. As a result,
representatives of OAR are members of the RCT and provide invaluable advice to ORD as it
develops its research agenda. Because the EPA Regions, States, and tribes are critical to rule
implementation, they themselves frequently have specific and immediate needs (some research,
some advisory) that ORD is challenged to address.
With finite resources, priorities or scaled emphases across needs are requisite if adequate and
timely progress (products) is to be achieved. As already noted, program priorities are established
within the RCT where partner needs and the appropriate science support can be negotiated
collectively toward consensus products. Although resources are critical in the final program
development, prioritization uses broad criteria, such as the likely magnitude of public health
impact, the narrowing of the greatest uncertainties affecting decision-making, and the
anticipation of information needed to support future OAR decisions or directions. The goal is to
achieve a research program structure that best meets these criteria. Because PM and ozone score
highly among these criteria and are NAAQS pollutants, they remain central to ORD's Clean Air
Research program (for both standard setting and implementation) and garner considerable
attention among other NAAQS and air toxic pollutants.
-------
The challenges and needs of ORD's clients/partners in the program offices and as users in the
field are many and multifaceted, and, therefore, this MYP cannot possibly address every research
issue identified as a need. Instead, OAR's highest priority regulatory and policy challenges
related to air quality that require the most significant research investment are highlighted below.
Within the challenges and needs expressed below, an attempt was made to reflect the perspective
of the user including those at the Office, Regional, State, or local levels.
a. NAAOS Setting and Implementation. The protection of public health (including susceptible
populations) through the development and attainment of appropriate, protective air quality
regulations is fundamental to the tasked mission of OAQPS. Clearly, meeting these regulations
in the most cost-effective and efficient manner is in the best interests of public health, the
environment, and the economy. There are six NAAQS that undergo repeated, periodic review to
meet the statutory requirement of the Clean Air Act (CAA), yet the estimated impacts of
reductions in ambient PM and ozone continue to drive the bulk of the public health benefit. The
other NAAQS also factor into the overall air pollution burden, but their risks appear less
substantial because of less exposure risk and/or ambient reductions, with lead recently gaining
renewed emphasis because of public interest and health impacts at levels not previously
appreciated. The uncertainties across the NAAQS are similar in magnitude and potential public
impact, and, as a result, the uncertainties underlying the standard setting process for PM and
ozone (with their potential impacts) sustains these two pollutants at the highest priority. Between
these two NAAQS themselves, the risks and benefits associated with PM and its reduction in
ambient air has retained the highest ORD interest and, hence, emphasis on PM.
More specific challenges related to the review of the PM and ozone NAAQS that require
research support include:
uncertainties surrounding the PM2.5 standards,
uncertainties surrounding the PMio standard (vis a vis coarse PM),
level and form of the ozone and PM standards,
uncertainties regarding co-pollutants in PM-associated health effects,
the potential for interactions between PM and ozone in health outcomes,
definition / characterization of populations that may be susceptible to pollutant effects,
and
potential for an alternative to the mass-based PM standard through identification of
hazardous components.
More specific challenges related to NAAQS implementation that require research support
include:
continuing nonattainment problems (post-sulfur/nitrogen controls),
uncertainties around predicting impacts of control strategies on air quality,
development of improved methods to effectively and rapidly measure pollutants,
uncertainties around the input variables for refinement of air quality models,
uncertainties around which sources contribute to ambient levels of PM, and
development of improved emission inventories.
Much of the current Clean Air Research program focuses on these challenges. As will be detailed
below under LTG 1, providing the research that underlies the development and implementation
-------
of the NAAQS is at the core of the research program. As the program evolves, as described in
this document, these research activities are being leveraged to expand both the level of
understanding of these NAAQS and the broader array of air pollutants and their effects alone and
as mixtures.
b. Mobile and Stationary Source Air Toxics. The 1990 CAA requires EPA to reduce emissions
and exposures to 188 specified HAPs (also known as air toxics). Air toxics emissions arise from
major stationary sources, smaller (area or point sources), on-road (cars and trucks), and non-road
sources (trains, construction equipment, barges, airplanes, etc.)Through implementation of the
Maximum Achievable Control Technology (MACT) program, many stationary sources have
installed available technologies to address risks of the 188 air toxics. The key challenge now
facing the EPA is to determine if there are unacceptable remaining ("residual") risks after these
technologies have been installed. There is need for refined emission inventories of HAP
emissions to support these residual risk determinations and to better estimate potential
community exposures. Because air quality monitoring of the HAPS is more limited than with the
NAAQS, the quality of the National Air Toxics Assessment (NAT A) for the various HAPs is
highly dependent on these inventories to model potential exposures.
One of the more significant challenges to upgrading the current emission inventory is the
assessment of those sources emitting pollutants over a wide geographic area rather than from a
single point source (e.g., a smoke stack). These sources can range from landfills to refinery leaks.
It will be critical to get a better handle on these emissions and understand the associated public
exposures to address such risks through residual risk standards or other regulatory designations
(area source standards). The NATA focus at present is on 177 HAPs thought to be of greatest
risk (by virtue of estimated exposure or compound toxicity) and on diesel exhaust emissions. The
hazard and dose-response analyses to support assessment of noncancer and cancer risks from
exposure to HAP compounds are being developed by the Integrated Risk Information System
(IRIS) program (in the HHRA program) using published data. Nevertheless, there is significant
need for information (e.g., mode of action, models) that can be used more broadly to reduce
uncertainty in risk assessments related to HAPs in the ambient environment.
Research among the HAPs is targeted in certain areas and otherwise leveraged from the NAAQS
program. The Health Effects Institute (HEI) provides a significant research base among selected
HAPs as to their risk as point sources or local "hot-spots." 9 Other research utilizes source-based
approaches to conduct health research (e.g., diesel) or emission assessments (including methods
development) as described above. As these provide insight into the PM issue, their investigation
has importance across client information needs. The use of specific HAPs as models that relate to
PM or its effects is also supported; however, specific study of HAP toxicity or its dose-response
for IRIS is generally not part of the sponsored program.
c. Near-Road/Traffic. Emerging information linking human proximity (living, working, or school
environments) to roadways with a range of adverse health effects has led to growing public
concern. These concerns have been communicated through OTAQ, ORIA, and OAQPS, as well
as from the EPA Regions as an area of great uncertainty, despite its priority. In fact, concerns
over potential health impacts from exposure to emissions near roadways have affected several
' HEI publications on air toxics: http://pubs.healtheffects.org/topics.php?topic=l&sort bv=pubdate&order=desc.
-------
transportation projects across the country, as well as a variety of policy decisions. Among these
are findings with respect to "conformity" of transportation plans and projects with State
Implementation Plans (SIPs) for attainment of the NAAQS and local decisions regarding the
location of schools and other projects (e.g., freight terminals) as required under the National
Environmental Policy Act (NEPA). These policy decisions are being made even though the
scientific uncertainties for the linkages to exposure, hazardous agents, and adverse health effects
vary greatly.
Near-road concerns cross a number of priorities among program clients. Mobile source
emissions comprise several HAPs (e.g., benzene, aldehydes, butadiene) as well as several
NAAQS (carbon monoxide, nitrogen dioxide, PM, lead). Most importantly, the emergence of
traffic as a source signal in the PM arena presents this source category as ideal for study. As
discussed further below, this source category has been selected as a prototype for multipollutant
study.
d. Moving Toward a Multi-pollutant Program to Support Air Quality Management Decisions.
Fundamental to a multi-pollutant approach to air quality management is the recognition of the
demands on the science to unravel the complex nature of the contributing sources, the
atmospheric chemistry, the human exposure/environmental deposition, and, of course, the
associated health and ecosystem impacts. A venture into such a broader based perspective has
begun with the recent review of the nitrogen oxides (NOx)/sulfur oxides (SOx) NAAQS (2007),
where the ecological impacts of these pollutants were considered together. With NOx/SOx, the
common theme of acidity and enhanced nutrients in the environment were used for the combined
assessment. However, if a multi-pollutant framework is to be more widely embraced for the
purpose of air quality management (human as well as environmental health), there is a real need
for research to develop analytic approaches to assess multi-pollutant human and environmental
health impacts, especially through multimedia pathways, with emphasis on indicators,
benchmarks, and interaction-based algorithms. To achieve such a goal, the air pollution sciences
will need unprecedented integration and will demand novel tools for assessment to aid
interpretation, develop implementation plans, and assess their effectiveness (outcome). Adding
to these needs as we move ahead in the 21st century, the challenge is heightened by the NAS
recommendation that future policies for air pollution control be integrated with climate change
criteria.10
OAQPS envisions the goal of a multi-pollutant approach to air quality as leading to a more
effective means of achieving environmental benefits and recently has undergone a reorganization
to reflect this multi-pollutant and sector-based (source) perspective. The office also has begun to
evaluate the technical issues associated with multi-pollutant approaches11 In this regard, a
National Air Pollution Assessment (NAPA)-the next phase of NAT A (for the year 2008)-is
being developed to include both air toxics and NAAQS pollutants in the context of exposure and
health risk and will further expand to include ecosystem and multi-media impacts. In addition, as
OAQPS moves toward more comprehensive, "sector-based" approaches for addressing sources,
there is a need to understand the amount and species of pollutants emitted from entire sectors and
the technological options that are most cost effective in reducing highest source risks. This will
10 NAS "Radiative Forcing of Climate Change: Expanding the Concept and Addressing Uncertainties," Oct., 2005.
11 The Multi-Pollutant Report: Technical Concepts & Examples: http://www.epa.gov/air/airtrends/studies.html.
-------
require new tools and models that can be used by decision makers to evaluate sectors in an
integrated manner.
Presently, the Clean Air Research program has a number of largely disconnected efforts
regarding multi-pollutant research. These include varied efforts in atmospheric modeling,
exposure measurements, and source characterization (methods and health). As described below
in LTG 2, ORD multi-pollutant efforts are adopting a source-to-health outcome paradigm, with
near-road impacts as the prototype for development of its research framework.
e. Assessing Health and Environmental Improvements Attributable to EPA Actions. There have
been marked reductions in several of the NAAQS pollutants over the last two to three decades.
Sulfur dioxide reductions and controls in combustion emissions have led to major environmental
improvements with reduced acid rain and deposition, but the benefits of reductions in other
pollutants have been more difficult to demonstrate in terms of health or ecology. Because of the
tremendous complexities involved in attributing changes in health or ecological status to changes
in air pollution alone, OAR has been challenged to find acceptable methods to show the benefits
of its decision making. As such, OAR has communicated the need for tools to measure the
impacts (in terms of benefits or reduced risk) of its decisions-an issue also known by the term,
"accountability." CAAAC has called for an "overarching accountability framework" that
includes a systematic effort to track air quality achievements and evaluate air program results.
According to CAAAC, the EPA needs to move beyond the current approach of relying
predominately on air quality measurements and develop and apply the capability and capacity to
monitor, assess, and report on how changes in emissions impact air quality, atmospheric
deposition, exposure, and effects on human health and ecosystems. There is also interest in
ensuring that use of a specific technology or combinations of technologies to reduce air
emissions in response to a particular regulatory requirement does not result in other unintended
environmental emissions or releases of concern.
Currently, there exists no formally sponsored ORD effort to address these needs largely because
of the complexity of the task and the many factors that exist as potential confounding. The
HHRP has initiated a cross-program discussion in an attempt to meet this need across program
areas, but, to date, this generic program has lacked the resources to be implemented. The Clean
Air Research program has been working with OAQPS to develop a framework tailored to its
needs, which builds on pilot activities such that a broader model can be built and substantiated.
This concept is being incorporated into the design of all planned Clean Air Research program
undertakings.
f. Indoor Air. People spend upwards of 90% of their time indoors. Understanding the infiltration
of outdoor air with its diverse pollutants into the indoor environment is further complicated by
contaminants from indoor sources. The public looks to ORIA for advice on indoor air problems,
as well as overall guidance on the issue. ORIA, in consultation with ORD, generated a document
entitled Program Needs for Indoor Environments Research, which included some key research
needs related to chemical and biological indoor contaminants to support future OAR guidance
and policy related to indoor exposure risks and guidance. Ideally, characterization of indoor
pollutant exposures, arising from either indoor sources or infiltration from sources outdoors,
provides the foundation for development of methods and strategies for controls and minimization
-------
of risk. Among the issues in the public eye are those related to asthma induction or exacerbation
(from contaminants or biological allergens), especially in children. On a different note, there is
also a growing movement related to green building design that increasingly will require
information that can be used to perform unbiased analyses of building materials selection and
installation procedures. For those buildings already in existence, the development of mitigation
strategies with assessments for their effectiveness are of great interest, especially those that
examine the effectiveness of EPA's Indoor Air Quality Tools for Schools guidance already in
place (notably for schools located near major roadways). As such, in the implementation of the
near-road research program, the Clean Air Research program is attempting to address selected
information needs (e.g., school infiltration, effectiveness of solid and vegetative barriers).
g. Ecological Research. The impact of air pollution on the ecosystem has long been appreciated,
especially with regard to acid deposition. To that end, the work of ORD has contributed
significantly to the steady reduction and ongoing assessments of that environmental stressor.
Given the need to review the secondary NAAQS that address welfare (notably ecological)
impacts of air pollutants, OAR continues to request support for data collection in the field and
associated assessments. With the passage of the Clean Air Interstate Rule (CAIR) and Clean Air
Visibility Rule (CAVR) in 2006, OAR's requests are underscored by the desire to develop
measures for eco-accountability. As such, identification of indicators and profiles of wet and dry
sulfur deposition are voiced as priority needs by OAR. New technologies also have been
requested to facilitate these assessments and to address related contaminants such as nitrogen
deposition from atmospheric ammonia. With the recent Supreme Court decision on carbon
dioxide (CO2) and growing climate and global change concerns, there likely will be an amplified
cry for tool development and broad based assessments related to the interface of land and water.
However, ORD's investments in these activities are limited and have been diminishing because
of increasing annual fiscal constraints.
h. Global Climate Research. The recent Supreme Court decision on CO2 and climate has
expanded greatly OAR's interest in quantifying climate impact on health, air quality, and other
socioeconomic and environmental systems. The linkages between air quality and climate are of
growing importance, but little is understood. OAR has increased interest and need for enhanced
models to incorporate better chemical, transport, and meteorological parameters both regionally
and globally. The interactions between climate change and air pollution loom as a major issue of
the 21st century, crossing all offices and program areas. OAQPS, in particular, has the challenge
of trying to forecast the impact of longer ozone seasons (compounded by enhanced PM by
transformation) and perhaps higher ozone levels on exposed human populations and ecosystems.
The Clean Air Research program is partnering with the Global Change Research program to
frame the nature of the issues and define specific research issues that can be integrated into both
programs to maximize effectiveness. At present, these activities are limited to assessments and
the development of a research framework.
i. Research to Support the Regions, States, and Tribes. The implementers of rules and policy
decisions are faced with many technical issues. They rely on tools and models developed by
ORD, as well as the latest technologies for monitoring and analyses. Cost efficiencies and quality
assurance are major concerns when applying technological changes especially for rule changes.
ORD must communicate these technology advances and assist in their field applications. The
10
-------
Regions, States, and tribes also have unique and often immediate needs because of their specific
geographies, socioeconomics, etc., that deserve attention from ORD. Assistance in the way of
advice and consultation frequently is provided and opportunities for real-world field testing
opportunities for ORD research activities is constantly sought. Nevertheless, the balance between
long-range policy targeted research and crisis or problem-solving research can, at times, be
strained and, thus, requires continual communication and nurturing.
2. External Program Reviews
A number of external organizations have performed reviews of the Clean Air Research program
and have provided critical feedback and recommendations that have been used to improve
program design.
Under Congressional directive, the NAS NRC identified 10 priority research topics in a series of
EPA sponsored reports published from 1998 to 2004. These documents provided key guidance to
the development of the Clean Air Research program and continue to be a major influence on its
evolution. The last report, released in April 2004, identified major science drivers and challenges
associated with managing the science to address key remaining research questions. These are
briefly articulated below along with the program's response.
Overarching Science Drivers
Completing the PM emissions inventory and PM air quality models necessary for NAAQS
implementation and for informing health research. New data on emissions are being added
regularly to databases used by OAR and the States to upgrade their inventories, and new
technologies are being developed and applied to sources previously poorly characterized.
New volatile organic compound (VOC) transformation algorithms are being incorporated
into the Community Multiscale Air Quality (CMAQ) modeling system that have improved
accuracy and served specific program office needs.
Developing a systematic program to assess the toxicity of different components of the PM
mixture. Bioassays are being applied uniformly to sources and emission/PM attributes to
assess their relative importance to toxic outcomes. Complementary study designs are being
used in human and animal studies to enhance extrapolation.
Enhancing air quality monitoring for research. Improved coordination with OAQPS, States,
and Regions shift current air monitoring from primarily assessing compliance toward serving
multiple purposes, such as air quality forecasting, episode alerts, exposure characterization,
health studies, and impacts of regulations. Workshops have proved to be important venues
for enhancing communication of research needs for input into monitoring strategies, as well
as tool development for data clarity and access.
Planning and implementing new studies of the effects of long-term exposure. EPA has funded
new long-term studies including a 10-year prospective multicity study of atherosclerosis
(MESA-Air; see below).
Improving the relevance of toxicological approaches. Improved study designs, focus on the
source-to-health outcome paradigm, and attention to species dosimetry will better link the
toxicology and epidemiology. Interdisciplinary and cross-Laboratory/Center project planning
allows leveraging of the science and complementary studies.
11
-------
Integrating disciplines. Discipline integration in study design and cross-project leveraging is
enhancing program efficiency and data interpretation.
Moving beyondPM to a multi-pollutant approach. A multi-pollutant program has been
initiated in LTG 2 (see below) using a source-to-health concept design.
Accountability: The concept of accountability (demonstrating an impact) is being
incorporated in all program areas. While a framework is being developed for broader Clean
Air Research application and OAR use, specific pilot projects have been initiated central to
this goal and, wherever possible, programs such as near-road have incorporated
accountability (e.g., impact of mitigation strategies) into project designs.
Challenges to Science Management
A higher level of sustained program-science integration and interaction. Under the direction
of a National Program Director, EPA's multiple air-related programs (NAAQS and HAPs)
have been integrated into a single Clean Air Research program to improve integration,
efficiency and science utility. As the climate issue grows, the linkages between air quality
and climate must be strengthened to meet the evolving demands of a sustained high level of
air quality management.
An integrated multidisciplinary research program that strives to elucidate the science and
linkages across the source-to-health outcome framework. Using the MYP as a guide,
research planning and execution will move ahead to maximally leverage resources and
provide the most complete understanding possible of the science questions vetted through the
RCT in the development of the Clean Air Research program agenda.
Stronger tools are needed to synthesize the large amounts of new information being
developed in the Clean Air Research program to support air quality decisions. Program
integration and improved access to and development of databases and web based information
have been undertaken. Regularly scheduled cross-organizational (Laboratory and Center)
meetings and coordination with other programs (e.g., HHRA, Global, HHRP) and client
offices (e.g., OAQPS) help assure effective targeting of research and communication of
findings.
A continuing mechanism for independent review and oversight of the program. The program
has been reviewed by an external panel of experts (BOSC). A program review occurred in
March 2005 and a mid-cycle review was conducted in September 2007. These periodic
programmatic reviews supplement independent science peer review of the program, along
with Laboratory, divisional, and peer review mechanisms in the extramural grants program.
A mechanism for gaining access to program science-oriented advisors to meet annually to
provide insight and critique is being explored.
Multi-pollutant assessments require strong interdisciplinary research framed by its utility to
the client/user: The program has partnered with its OAR and its Regional clients to develop a
research agenda that feeds their need to better understand the science linkages from source
emissions to health outcomes that will lead to the development of better tools and models for
decision-making.
The select-subcommittee of EPA's BOSC that reviewed the PM and ozone programs in March
2005 made a number of general and specific recommendations. These recommendations (see
below) have been incorporated into the current MYP.
12
-------
The LTGs be reworded to succinctly focus on the essential responsibilities and desired
direction of the program. The revised LTGs contained in this MYP are consistent with the
BOSC recommendations.
The MYP include a discussion indicating how the goals set out by the NRCflow into the
cross-cutting research issues and how these are embodied under the two LTGs. If this
discussion is in the Research Strategy for the Program, the MYP needs to be organized to
make the connection between the research and the NRC goals obvious. The MYP as
described under its LTGs provides this research strategy that now encompasses more than the
NAAQS and orients to the source-to-health outcome paradigm. The PM program historically
has been aligned closely with the NRC topic areas and continues to be so. PM publications
are categorized as such, but across the Clean Air Research program, the research that flows
from the two LTGs is envisioned to support the new paradigm.
The PM-Ozone Program should commit to maintain the strong balance between intramural
and extramural research. This MYP maintains that balance and fully integrates the
extramural (NCER: Science to Achieve Results-STAR) program activities (approximately
35%) with the intramural program comprising approximately 65% (inclusive of staff and
program infrastructure). The research activities complement or elaborate upon one another to
provide the integrated research that addresses OAR priorities.
The full BOSC report can be found at http://www.epa.gov/osp/bosc/pdf/pm0508rpt.pdf, and
EPA's response can be found at http://www.epa.gov/osp/bosc/pdf/pm0602resp.pdf. The mid-
cycle (2007) BOSC report can be found at http://www.epa.gov/osp/bosc/reports.htm.
3. OKD Laboratories and Centers
The research described in the Clean Air Research program MYP is conducted by investigators of
ORD's National Exposure Research Laboratory (NERL), National Health and Environmental
Effects Research Laboratory (NHEERL), and National Risk Management Research Laboratory
(NRMRL) and by awardees of its extramural grants program, funded through the NCER STAR
program. In addition, the National Center for Environmental Assessment (NCEA), while not
funded through this MYP, plays a major role summarizing the latest scientific findings related to
the effects of PM, ozone and other criteria pollutants to support development of future NAAQS
standards. NCEA also conducts risk assessments (IRIS values) for high priority air toxic
pollutants including associated assessments of residual risk after implementation of controls.
There are also collaborative projects between ORE) Laboratories and Regional scientists referred
to as RARE (Regional Applied Research Effort) to enhance real-world research applications or
to pursue unique opportunities.
ORE) Clean Air Research program investigators are in a unique position within the research
community because they conduct research to address pressing science data gaps that underlie
regulations, as well as develop models, tools, and strategies to implement regulations or
otherwise mitigate air pollution. The diverse nature of problem-solving research requires both
breadth and depth across diverse scientific disciplines. ORD acquires the needed skill mix
through the coordinated use of its intramural scientists housed within ORD's Laboratory
structure, as complemented by the many talents of the academic community accessed through the
13
-------
STAR program in NCER. ORD supports leading-edge research across the air pollution sciences.
These include integrated epidemiological, clinical, and toxicological investigations of the health
effects of PM and co-pollutants, with a systematic focus on components and sources, the
identification and quantification of factors influencing actual human exposures, the development
of ambient monitoring methods and air quality models used for compliance purposes, the study
of basic atmospheric sciences to support these air quality models, and the development of
specialized technologies for the measurement and control of diverse emissions. ORD is also
unique as a research institution because of the close proximity of its intramural exposure, health,
atmospheric science, and engineering researchers. The Clean Air Research program continually
strives to coordinate its research agenda to the extent possible to provide coherent and relevant
data and to maximize its ever-strained resources.
4. Client-Partners for Air Research
ORD has a unique relationship with the prime users of its research products. The users are
involved in the prioritization of its research and, depending on the nature of the research, the
users function as collaborators. Such collaborations help shape the product and ensure its
relevance and utility. The client-partner for the work described in this MYP is EPA's Air
program office, OAR. ORD's research to address uncertainties in the standard-setting process
also deals with the rule implementation needs. Implementation research assists EPA Regions,
States, tribes, and regional planning organizations (RPOs) in their activities to reduce ambient
concentrations of air pollution, exposures, and, ultimately, adverse health effects. ORD research
is key to its own office (NCEA) responsible for NAAQS pollutant science assessments (and,
secondarily, the air toxics) used by the Agency in risk management decisions as described in the
HHRAMYP.
In addition to supporting EPA's regulatory process, ORD's Clean Air Research program also
supports environmental protection standard setting beyond the borders of the United States.
Several countries in the European Union rely on ORD's research in environmental decision-
making, and international organizations such as the World Health Organization rely upon ORD
outputs and expertise to inform their activities and conclusions. Similarly, ORD works with
scientists and policy-makers from numerous countries (e.g., Canada, Mexico, Netherlands,
Germany) through informal collaborations or more formal Memoranda of Understanding to
promote the exchange of the latest scientific knowledge in support of policy development.
5. ORD Partners in Research
Air pollution research is also conducted outside the EPA, and ORD keeps abreast of this research
and coordinates its own activities with these to the extent possible. In some cases, a close
collaborative relationship exists, such as with the National Oceanic and Atmospheric
Administration (NOAA). ORD has worked closely with NOAA for more than 35 years with a
focus on the development of air quality models appropriate for atmospheric research, standard
implementation, and pollution forecasting. This relationship remains strong with the growing
need for integration with changing meteorological and climate sciences.
14
-------
HEI, funded jointly by EPA and the motor vehicle industry, is another important partner in the
support of ORD's mission. HEI-sponsored research is coordinated with ORD/EPA and
conducted through requests for proposals, drawing from the diverse academic community to
focus on issues or questions not readily pursued within the government laboratory structure.
Notably, HEI-sponsored activities in the independent reassessment of epidemiological findings
have been invaluable to EPA in the regulatory decision-making process. Research support also is
provided by the National Institutes of Health, including the National Institute of Environmental
Health Sciences (NIEHS) and the National Heart, Lung, and Blood Institute (NHLBI), and select
industrial organizations, including the Electric Power Research Institute (EPRI) and the
Coordinating Research Council (CRC)the latter through its support of HEI. In recent years,
ORD has co-funded requests for applications (RFAs) and workshops with NIEHS and NHLBI
and continues to explore opportunities for similar co-funded initiatives. Most recently, the Clean
Air Research program has initiated efforts to coordinate its extramural research with the funding
agencies already noted along with the California Air Resources Board, which has a significant
air pollution research agenda.
In an effort to better coordinate with the broader air pollution research arena, EPA takes the lead
role in communicating its research goals and program structure with other public and private
organizations through two coordinating bodies: 1) NARSTO12 and 2) the White House CENR,
AQRS.13 These groups meet regularly (about monthly) to communicate program findings and
directions to coordinate and leverage activities wherever possible. In addition, there are several
groups conducting air quality studies, including ambient PM measurements by the U.S.
Department of Energy (DOE) in the upper Ohio River Valley and multi-agency state efforts in
California and Texas. Multi-state organizations such as Northeast States Coordinated Air Use
Management and RPOs in the Midwest also are sponsoring studies of ambient air quality. In
emission characterization and inventory development, the U.S. Department of Agriculture is
providing support for research to improve emission inventories for ammonia from agricultural
operations. There are also several projects related to emission inventory improvement and air
quality model application being conducted by States and the RPOs. Further emission inventory
and characterization work is being conducted or supported by EPRI, the American Petroleum
Institute and Gas Technology Institute, and the CRC.
As noted earlier, EPA stays abreast of this work (both health and implementation research) via
its formal participation in the CENR and NARSTO, continuous interactions with Federal
colleagues, and through scientific and technical conferences and organizations. Information on
these complementary research activities is taken into account by both principal investigators and
ORD scientific and technical management when research needs are evaluated, and efforts are
undertaken to meet the priorities of OAR and the goals of the MYP. Presently, ORD is co-
leading an effort with HEI to promote coordination of ongoing research across these many
sponsors and to provide a central resource of information for research on air pollution issues.
12 Formerly an acronym for "North American Research Strategy for Tropospheric Ozone," the term NARSTO has
become simply a wordmark signifying the tri-national, public-private partnership for dealing with multiple features
of tropospheric pollution, including ozone and suspended paniculate matter.
13 http://esrl.noaa.gov/csd/AQRS/.
15
-------
EPA also works cooperatively with the Department of Defense through the Strategic
Environmental Research and Development Program (SERDP) to conduct research of interest to
both agencies. SERDP annually issues statements of need, many of which have air emissions
implications. Similarly, partnerships have been formed with DOE to evaluate promising
technologies to reduce air emissions from coal-fired power plants and other energy sources.
6. Resources
The research described in this MYP covers the next 5 years and is based on an assumption that
the total available resources will remain nominally constant. EPA allocated approximately $78
million dollars and 245 full-time equivalent personnel to air research in fiscal year 2007. Of the
total funding, $42 million was for personnel compensation and benefits, travel, information
technology, operating expenses, capital equipment, and repairs and improvements. The
remaining $36M was for research and support expenses spent via contracts and grants. The
president's fiscal year 2008 budget requests $81M and 236 full-time equivalent personnel for air
research.
II. THE CLEAN AIR RESEARCH MULTI-YEAR PLAN
A. Changes from the Previous MYP
This MYP combines and integrates three previous MYPs and research strategies (PM, ozone,
and HAPs) into a single plan to better coordinate and leverage research across all themes. Earlier
MYPs approached each program area separately with little cross-theme coordination and
integration. Budgeting (both proposals and tracking) was also separate. As already noted, the
science and regulatory programs are evolving toward a multi-pollutant perspective that better
reflects the realities of human exposures and offers the potential for more effective control and
public health protection.
At the core of this MYP is a major shift in ORD's approach to research in the air pollution
sciences. Previously, each MYP relied on several loosely connected L/C-focused LTGs
addressing a wide range of specific science supporting regulatory functions. The present MYP is
shaped around two overarching LTGs that continue to support the regulatory requirements of the
program office while developing the science to link health effects to air pollution sources and
components. The latter approaches air pollution from its origin as source emissions, through
atmospheric transport and transformation, to exposure, dose, and human health outcomes. It
emphasizes science planning coordination to leverage across programs and achieve efficiencies
in both science and budget. To this end, this MYP has adopted a two-pronged approach:
1. Continue to support the needs of EPA, and state and local governments, developing
the underlying science for developing health-based standards to regulate air pollution
regulations and developing tools to implement strategies to meet those standards to
protect public health and the environment; and
16
-------
2. Pursue scientific advances that will lay the foundation for the next generation of air
pollution standards and management strategies.
B. Long-Term Goals
This dual approach is reflected in the adoption of two LTGs for this research plan:
LTG 1. In accordance with EPA's legislated mandate for periodic NAAQS assessments
and assessment of HAP risks, advances in the air pollution sciences will reduce
uncertainty in standard setting and air quality management decisions.
(Short title: Reduce uncertainty in standard setting and air quality management
decisions due to advances in air pollution science.)
LTG 2. Air pollution research will reduce uncertainties in linking health and
environmental outcomes to air pollution sources to support effective air quality
management strategies.
(Short title: Reduce uncertainties in linking health and environmental effects to air
pollution sources.)
The first LTG (LTG 1) supports the following two research themes:
1) Developing the NAAQS and other air quality regulations; and
2) Implementing air quality regulations.
The second LTG (LTG 2) is oriented toward three research themes
3) Launching a multi-pollutant research program,
4) Identifying specific source-to-health outcome linkages, with initial emphasis on "near
roadway" impacts, and
5) Assessing the health and environmental improvements due to past regulatory actions.
C. LTGs in Relation to Air Program Needs, Priority Science Questions and APGs
EPA is mandated to periodically (at 5-year intervals) reassess the adequacy of the six NAAQS
(PM, ozone, SO2, NO2, CO, and lead) and reaffirm or revise each specific standard. ORD
provides and supports the science to conduct these assessments, as well as the science and
engineering needed to implement the standards at the appropriate regulatory jurisdictions. In the
case of HAPs, the CAA requires EPA to develop emission standards for sources, known as
MACT standards, based on the best controlled similar sources. Following implementation of
MACT, EPA must assess risks remaining to human health and the environment, and must
promulgate additional emission standards if appropriate. Although secondary to the NAAQS in
program priority, ORD can, under this revised MYP, similarly provide science related to these
HAPs issues, particularly through project integration.
17
-------
As can be seen in Figures 3 and 4, the critical science questions for the Clean Air Research
program (as derived from the major policy challenges identified by our clients and external
program reviews) flow into these two LTGs. The vision is that, over time, increasing emphasis
will be given to multipollutant approaches. As critical steps in fulfilling the LTGs, the APGs will
strategically reduce uncertainty in assessments, the impacts of which should be more readily and
realistically measured. However, the progression of science is always incremental, and it is likely
that in reducing some uncertainties others will be unveiled. Nevertheless, science has always
built from such a process, and there is sufficient flexibility in the various products and the MYP
to allow for midcourse adjustments. The specified APGs and related science products (APMs) to
meet these goals evolved from deliberations within the EPA Air RCT and they have been vetted
through senior management.
18
-------
Science Questions Outcomes
What is the role of physical-
chemical characteristics of air
pollutants in eliciting adverse ,
short- and long-term health >
effects, especially in susceptible
populations?
Which sources of air pollution ^H
most severely impact exposure
and health, and how does this
vary across the country?
What are the characteristics of air ^^
pollutant emissions from different L
types of sources, and how do
transformations in the atmosphere
affect air pollutant concentrations
and human exposures?
What are the expected future i
concentrations of air pollutants,
PM standard revisions will more effectively address:
Size fractions, components, and sources responsible for adverse health
1
Improved understanding of exposure-dose-response relationships,
Health endpoints outside the cardiopulmonary system,
Understanding mode-of-action of air pollutant-induced health effects, and
Health effects in susceptible populations.
Use of air quality and receptor models to develop SIPs and control strategies
and forecast air quality.
Use of advanced techniques to better characterize emissions and ambient
concentrations of air pollutants, leading to improved risk management
decisions.
Use of advanced tools, models and technologies to formulate policies to
reduce PM level in residual non-attainment areas.
Development of improved risk management strategies via better inventories
and enhanced capacity to determine which sources contribute to measured
> ambient levels of PM.
and how can we evaluate and j I
manage their potential adverse ^"
consequences? Reduce uncertainty in standard setting and air
quality management decisions due to advances in air
pollution science
Long-Term Goal 1
Figure 3. LTGI Critical Science Questions
Science Questions
How can we assess and manage ^^
risks from real-world exposures *
involving complex mixtures of air
pollutants that fall into multiple
physical-chemical classes?
Which sources of air pollution
most severely impact exposure i |
and health, and how does this
vary across the country?
How can we determine how past ^^^
regulatory decisions have reduced *
exposures to air pollution and
improved health outcomes?
Outcomes
ORD research will be used to inform consideration of alternatives to a mass-
based standard and target air quality management strategies.
Researchers and policy-makers will use ORD tools to understand
relationships between sources and ambient air concentrations.
Federal, State and local agencies will use ORD tools to measure gradients of
emissions from roads and to understand what these mean for exposure
and risk.
> Improve understanding of the contribution of specific sources to risks, thereby
reducing the uncertainty associated with evaluating the public health
impacts of those sources.
Establish relationships that provide the capability to directly link field
measurements to health indicators.
EPA will develop and begin to implement approaches to assess the
t effectiveness of regulations and control strategies in reducing impacts to
the environment and human health.
ORD will identify technology performance information for air quality officials
who will use that information to improve performance and minimize
releases.
*
Reduce uncertainties in linking health and
environmental effects to air pollution sources
Long-Term Goal 2
Figure 4. LTG II Critical Science Questions.
19
-------
LTG1
In accordance with EPA's legislative mandate for periodic NAAQS assessments and
assessment of HAP risks, advances in the air pollution sciences will reduce uncertainty in
standard setting and air duality management decisions.
Under this goal, ORD highlights two themes that provide direct support to OAR's mission: 1)
development of the NAAQS and other air quality regulations and 2) implementation of the air
quality regulations (see Figure 4). These themes focus on the standards that are used to regulate
air pollutants in keeping with the traditional roles of ORD relative to the OAR regulatory
program. Theme narratives are provided to demonstrate the continuities within the program with
underlining of phrases to note their linkage to APGs in Tables 1 and 2. Satisfaction of individual
APGs generally does not necessarily conclude research under that topic but, rather, registers a
time point for assessment of the knowledge at that time as it relates to the regulatory need. This
may impact a level of emphasis of this research thereafter or shifting of focus based on that
knowledge. Some fundamental questions (e.g., regarding size, composition, susceptibility, model
delivery) may require continued investigation to address ongoing program office needs.
Theme 1: Support for the development of the NAAQS and other air quality regulations
ORD plays a key role in the development process of air quality standards. ORD peer-reviewed
research results are the strong foundation on which ORD builds the assessment of both human
health and environmental impacts for each air pollutant. ORD staff also is involved heavily in the
design and review of the NAAQS policy options developed for the Administrator. Similarly,
ORD staff is involved in the development of the toxicological data base and mode-of-action
models, and their use in the HAPs risk assessment process, and in the various rule-making
actions by OAR offices (e.g., OTAQ). At the highest level, ORD provides direct scientific
consultation to the Administrator in proposed and final air regulatory decisions.
Uncertainties exist in all scientific investigations, and the Clean Air Research program directs its
attention to those of highest priority to its clients and the scientific community. Uncertainties
surrounding coarse particles (PMio-2.s) were noted specifically in the promulgation of the most
recent PM regulations. Also, there continues to be considerable interest in the significance of
ultrafme particles, relative to fine particles (PM2.5), as to their potential role in causing adverse
health effects. To address these questions, one research goal is to investigate exposures and the
role of different PM size fractions in health outcomes (APG 1). Another priority of interest to
OAR is exploring the potential for alternatives to the current PM mass-based standards. As the
science has been more complex in this area than originally anticipated, research on exposure and
health effects of PM components (APG 2) [some of which are among the 188 HAPs] is ongoing
under LTG 1. Additional research on components is being conducted under LTG 2 (see below).
Different views about the annual PM standard emphasize the need for additional studies on the
health effects of long-term exposure to PM2 5 (APG 5).
Much work continues on the potential exposure and health outcomes associated with air
pollution. As per RCT-determined priorities, PM research occupies much of the program effort;
however, some health research addressing specific pollutant-relevant questions is conducted as
well. Ozone, for example, is the most ubiquitous oxidant in the ambient air and has known
20
-------
toxicity at regularly encountered levels. The essential database for ozone assessments largely has
emanated from ORD research efforts over the past 30 years. In the past 10 to 15 years, PM has
come to dominate the health program, but ozone questions are addressed as specific needs arise
or when it can function as a model (e.g., genetic susceptibility). Recently, functional outcomes at
concentrations well-below the NAAQS have been reported, and OAQPS has specifically
requested that the research program conduct replicate studies at similar concentrations. However,
these efforts remain modest. In another context, ozone has gained some prominence because of
evidence of potential mortality impacts and morbidity at levels below the 1997 NAAQS. The
Clean Air Research program monitors these studies but is not directly pursuing this issue.
On the other hand, questions about PM and co-pollutant (including ozone) risks (APG 5) is
gaining prominence on the health science agenda. Air toxics research will be undertaken for
specific HAPs that are most prominent in PM-polluted air sheds, especially if linked to mobile
sources. To that end, the relative and interactive roles of specific pollutants in causing effects
continue to be investigated to define causation and refine our understanding of biologic modes of
action (APG 6). Most health research supporting air toxics IRIS assessments is found in other
MYPs (e.g., HHRP, HHRA, and Homeland Security.)
Intrinsic to this research is the evolving importance of "who is susceptible to which effects,"
defining factors affecting susceptibility (APG 3) to adverse health outcomes, and examining
gene-environment interactions. Recent work on susceptibility has uncovered the potential for
health effects of air pollutants beyond the cardiopulmonary system (APG 4), which may have
implications for additional susceptible subgroups. With risk assessments providing the basis for
development of risk management options, providing up-to-date information on exposure-dose-
response relationships (APG 7) is a key area of program support. Targeted studies to address the
level and duration uncertainties with ozone have been considered and, if implemented, may
displace lower priority PM research.
To the extent possible, the health research is interdisciplinary, not only across health disciplines
but across the physical sciences, including exposure science and air quality assessments. As
such, maximum power is gained to address potential interactions among pollutants, as well as to
assessments of specific roles of other pollutants, including selected air toxics, in causing health
effects.
21
-------
2008
2009
2010
Improved info rmation
for hazardous ai r
poll utants
Adva need air quality
models
Roles ofdifferentPM
size fractions
Advanced techniqu es
for source and arrbie nt
PM, precursors, and
toxics
Tool s to li nk health a nd
ecosystem impacts to
air pollution sou ices
Integrated multiple
pollu tant research
program strategy
Frameworkto assess
the effecti vene S3 o f air
pollution regulations
and control strategi es
Research Themes
1 - Support development of NAAQS and other air qual ily regul atio ns
2 -Support for implementation of air quality regulations
- Pursu ing a multi -p ollutant approach
4 - Identify ing source-to-h ealth lin kages
5 -Assessing health and environmental improvements due to past
Agency actiwties
2011
Factors affecting
susceptib ility to
ad verse health
outcomes
Evidence f or e ff ects of
air poll utents beyond
the cardiop ulrron ary
system
Effects of long-term
exposure to PM25
Data and tools to
assess the importance
of p articles i n residual
non attainment
Air quality modelin g
system that couples
meteorology and
prowdes early warning
regarding ozone and
PM2.5
Emissions facto is and
chemical composition
dataf or dispersed
source s of air p d lutants
2012
Exposure to PM
components and their
role in health effects
Importan ce of key
biolog ic pathways
Ambient concentration
and exposure-dose-
respon se relationships
Improved source-
rece ptor based methods
and models
Sg nif ica nee of near road
emission s'exp osu re s
and rel ated health risks
from mobile sources
Mul ti-city/multi-pollutant
studies to assess the
relative health impacts of
sources
/Approaches to re1 ate
SDU rces/ambie nt air to
health effects
Evaluate whether control
technologi es are
a chie wn g the reductions
anticipated
Refine accountability
framework
Figure 5. APGs by Theme. [Note that some APGs relate to more than one theme, but have been assigned to a primary theme.]
-------
Table 1. APGs and APMs for LTG 1, Theme 1
APG1
ARM 1
ARM 2
APG2
APMS
APM4
APMS
APM6
APM7
APMS
APM9
APGS
APM 10
APM11
APM 12
APM 13
APM 14
APG4
APM 15
APG/APM Title Year Lead
Evaluate exposures to different PM size fractions and determine
the role of those fractions in particle-associated health effects
Characterize physiologic and biochemical responses of individuals,
animal models, or cultured cells to different size PM fractions and define
the mechanisms by which each size fraction causes effects
Provide exposure and health effects data on urban and rural coarse PM
in support of the NAAQS
Evaluate exposure to PM components and the role of those
components in particle-associated health effects
Report on how the presence and levels of PM components impacts
particle related health effects
Identify health effects associated with components of ambient particulate
and gaseous co-pollutants
Identify new biomarkers of exposure and/or effects to specific PM
components and associated gases
Provide a comparative toxicity testing framework and rank the relative
potency of PM components, testing particles from a broad range of
different sources including mobile and industrial sources
Develop data on the size distribution and detailed chemical composition
of combustion-generated particles produced from full- and pilot-scale
systems for use in real time inhalation toxicology studies
Complete field data collection for field studies to assess ambient, indoor,
outdoor, and personal exposure to PM constituents and co-pollutants
with potential for short-term health effects and compile a database of
toxic agent concentrations, exposures, participant activities, and
exposure factors
Develop data and models to evaluate relationships among PM size,
components, sources, ambient concentrations, and personal exposures
Elucidate the susceptibility and vulnerability factors that increase
risk with adverse health outcomes associated with air pollutants
Report on the results of studies illustrating how factors of susceptibility
impact air pollution responses
Determine the extent to which genetic polymorphisms present in a
significant portion of the population or differences in gene expression
patterns in animal models explain why some people are more
responsive to air pollutants than others
Determine whether there are host susceptibility factors, such as disease
phenotype, lifestyle, or life stage, that make people with cardiovascular
and/or pulmonary disease more susceptible to the effects of air
pollutants
Evaluate whether there are pharmaceutical or dietary interventions that
can protect susceptible populations from the effects of air pollutants,
and, if so, what are the mechanisms by which these interventions
protect people?
Develop data and models to identify subpopulations with
disproportionately high exposures to air pollutants
Provide exposure-based evidence for systemic effects of air
pollutants other than those on the cardiopulmonary system
Characterize the long-term health effects of short- and long-term low-
2009
2009
2009
2012
2009
2012
2011
2012
2008
2008
2010
2011
2009
2011
2011
2011
2011
2011
2010
NHEERL
NHEERL
NCER
NHEERL
NCER
NHEERL
NHEERL
NHEERL
NCER
NHEERL
NCER
NHEERL
NCER
NRMRL
NRMRL
NERL
NERL
NHEERL
NHEERL
NHEERL
NCER
NHEERL
NCER
NHEERL
NCER
NERL
NHEERL
NHEERL
-------
APG/APM Title
level exposure to air pollutants
Year Lead
Due Lab
NCER
ARM 16
Evaluate the importance of early life exposures to air pollutants, and
whether they are predictive of future effects later in life [also under
Susceptibility]
2011
NHEERL
NCER
ARM 17
Characterize the mechanisms by which air pollutants affect extra-
cardiopulmonary organ systems and associated effects
2010
NCER
NHEERL
APG5
Provide an assessment of long-term exposures to fine particulate
matter (PM2.s) and gaseous co-pollutants, specifically nitrogen
oxides, as determinants of regional and intra-urban differences in
the prevalence of subclinical indicators of cardiovascular disease
2011
NCER
ARM 18
Develop a model for assessing regional and intra-urban differences in
ambient long-term PM concentrations in nine U.S. communities
2009
NCER
ARM 19
Evaluate the association of the prevalence of subclinical indicators of
cardiovascular disease with regional and intra-urban differences in
estimated long-term exposures to PM2 5
2010
NCER
ARM 20
Evaluate the modification by co-existing health conditions (e.g.,
diabetes, hypertension, obesity) and individual-level factors (e.g.,
race/ethnicity, gender) of the association of the prevalence of subclinical
indicators of cardiovascular disease with estimated long-term PM
exposures
2011
NCER
APG6
Evaluate the importance of key biologic pathways in explaining
how air pollutants cause adverse health outcomes
2012
NHEERL
ARM 21
Determine if there is a common molecular mechanism (e.g., production
of oxidative stress, phosphatase inhibition, disruption of iron
homeostasis) through which air pollutants induce toxicity.
2012
NHEERL
NCER
ARM 22
Identify the mechanisms by which air pollutants cause adverse health
effects
2012
NCER
NHEERL
APG7
Characterize the ambient concentration and exposure-dose-
response relationships for PM and other priority air pollutants
2012
NHEERL
ARM 23
Characterize the effects of ozone exposure in selected populations at
exposure levels near the standard
2010
NHEERL
ARM 24
Can predictive exposure-dose-response models be developed to
improve the accuracy and precision of predictions of human health risk
from experimental data from animal and in vitro experiments?
2012
NHEERL
ARM 25
Report estimates from epidemiological studies of changes in health
outcomes associated with changes in ambient PM2 5
2010
NCER
Theme 2: Support for implementation of air pollution regulations
Development of strategies to meet national air pollution regulations for PM and ozone requires
extensive knowledge about current ambient concentrations, sources that contribute to the
measured levels, and the impact of emissions and associated atmospheric processes on future air
quality. ORD provides fundamental science to develop and improve tools that are essential to air
quality management at all levels, including OAR, Regions, States, and tribes. The State
Implementation Plans (SIPs) that provide details on actions that will be taken to reduce
emissions are heavily dependent on the models and other products produced under this research
theme. CMAO (APG 9, II) is widely used by States to inform their SIP development. CMAQ is
updated annually and improved based on the latest research on emissions (APG 8) and
24
-------
atmospheric science (APG 12) from ORD and the broader air quality research community. In
addition to these inputs, CMAQ must be coupled with meteorology models (APG 9) to generate
future estimates and forecasts (APG 12) of ambient ozone and PM. Similarly, efforts are
underway to link CMAQ to climate models as the science moves toward a more realistic
approach to studying climate and air pollution interactions (found in the Global Change Research
Program). As these multi-pollutant (one-atmosphere) models are refined, new emission factors
(APG 13) and refinements are needed at local and community scales to better estimate
population exposures to HAPs for risk assessment. Indeed, assessing exposures with empirical
field data and model development are important links between source emissions, atmospheric
transformation products, and human exposure. Source apportionment (APG 10) science is also a
key component of this theme. It depends both on measurement techniques (APG 10) to
characterize sources and ambient concentrations and receptor-based models (APG 14). The
identification of source categories contributing to ambient concentrations provides the basis for
targeted, cost-effective control strategies. Hence, the broad use of these implementation tools
requires not only that ORD conduct high-quality relevant research, but also provide its key
clients with the results in understandable and useful formats.
The issue of HAPs (air toxics) ranks highly among OAR and regional priorities, but second
to PM and ozone. As such, compared with ORD's research investment on the PM issue,
including co-pollutants, dedicated research on air toxics is relatively small. The MYP includes
one goal to improve emissions, concentrations, and exposure estimates for HAPs (APG 8).
Table 2. APGs and APMs for LTG 1, Theme 2
APGS
ARM 26
ARM 27
ARM 28
ARM 29
ARM 30
ARM 31
APGS
ARM 32
^^^J^^ABffl]
Provide improved measurement systems, data to better quantify
and estimate emissions, concentrations, and exposures, and
health effects information for indoor and ambient hazardous air
pollutants
Demonstrate improved methods for measuring ambient and personal
concentrations of acrolein and 1,3 butadiene
Enhance air quality and exposure modeling tools to address finer
scale air toxics concentrations and exposures
Collect and analyze existing data to understand critical factors which
influence relationships between human exposure and ambient air toxic
concentrations (existing ARM 32)
Develop and validate the Jet REMPI technology for real-time
measurement of trace organic air toxics from multiple sources.
(APMs 30 and 278 are consolidated)
Update AP-42 emission factors for landfills
Provide a summary report of past results and future directions for the
air toxics research program under the Multipollutant Air Research
Program and how IRIS risk assessment health effects support needs
will be addressed
Provide advanced air quality models that incorporate the latest
atmospheric and emissions data to OAR and States
Deliver to OAR the simplified and evaluated regulatory version of the
PM chemistry model (existing ARM 386)
Year Lead
Due Lab
2008
2008
2008
2008
2008
2008
2008
2008
2007
NRMRL
NERL
NHEERL
NERL
NERL
NERL
NRMRL
NRMRL
NHEERL
NERL
NERL
25
-------
ARM 33
ARM 34
ARM 35
ARM 36
APG10
ARM 37
ARM 38
ARM 39
ARM 40
ARM 41
APG11
ARM 42
ARM 43
ARM 44
ARM 45
ARM 46
ARM 47
ARM 48
ARM 49
ARM 50
APG/APM Title
CMAQ model system release and evaluation, including improved
capability for aerosol processes, especially secondary organic aerosol
production
Release peer reviewed EPA receptor modeling tools to be used by
States to enhance their ability to develop SIPs
Transfer information to OAR and States regarding characteristics of
open burning of biomass in wild and prescribed fires (existing ARM
224)
Produce a prototype tool to improve the geographic allocation of
emissions for use in air quality models
Deliver new and improved techniques to measure and
characterize source and ambient concentrations of PM and PM-
related precursors and toxics
Verification of Portable Optical and Thermal Imaging Devices for
LDAR
Evaluate and improve methods to characterize ammonia (including
ammonia nitrate and ammonia sulfate) concentrations in the ambient
environment
Provide to OAR, States, and the scientific community improved
methods for organic speciation of fine particles (existing ARM 319)
Provide to OAR, States, and the scientific community improved
methods for measuring the organic carbon and elemental carbon
fractions of PM (existing ARM 320)
Improve measurement methods for molecular tracer species and
identify new molecular tracers.
Provide models, data, and tools to better manage PM in the
atmosphere, including carbonaceous particles that contribute to
high levels of PM in areas of the country where NAAQS
attainment will linger even after national rules are implemented.
Study secondary organic aerosol formation mechanisms, including
cloud processing, aromatic precursors, and biogenic precursors
Improve linkages between emission sources and atmospheric
transformation processes for primary carbonaceous PM and
secondary organic aerosol precursors
Complete development of novel analytical methods that can be used
to determine the chemical and physical properties of combustion
emissions and atmospheric aerosols and provide guidance on their
use to OAR and State agencies
Integrate receptor, source-based, and inverse modeling for PM source
apportionment.
Improve the SOA chemistry model for CMAQ to include additional
anthropogenic SOA sources.
Produce an operational emissions allocation tool, compatible with the
OAQPS Emissions Modeling Framework
Measurement of ammonia air-surface exchange in forest and
agricultural landscapes
Evaluate computational atmospheric chemistry approaches to
determine whether they can be used to develop chemistry sub-models
Improved CMAQ modeling system for use in urban-scale residual
nonattainment areas
Hg
2008
2008
2008
2008
2009
2009
2009
2007
2007
2009
2011
2008
2008
2008
2009
2011
2011
2011
2011
2011
Lead
Lab
NERL
NERL
NRMRL
NRMRL
NRMRL
NCER
NRMRL
NERL
NRMRL
NERL
NERL
NCER
NRMRL
NCER
NCER
NCER
NRMRL
NCER
NERL
NRMRL
NRMRL
NERL
NERL
26
-------
ARM 51
APG12
ARM 52
ARM 53
ARM 54
ARM 55
ARM 56
ARM 57
ARM 58
APG13
ARM 59
ARM 60
ARM 61
ARM 62
ARM 63
ARM 64
APG14
ARM 65
ARM 66
ARM 67
ARM 68
APG/APM Title
Develop CMAQ linkages to global chemical transport model
Develop modeling systems that couples air quality and
meteorology models for better estimates and forecasts of
ambient ozone and PM2.s
Develop and test a prototype 2-way coupled WRF-CMAQ modeling
system
Analysis and evaluation of PM forecast simulations over the
Continental United States using a developmental version of CMAQ
CMAQ modeling system used for fully operational daily forecasting of
both ozone and PM2 5
Develop improved chemistry model for CMAQ to predict ambient
concentrations of organic and inorganic nitrates in PM2.5
An operational 2-way coupled WRF-CMAQ modeling system will be
released publicly
Apply the prototype 2-way coupled WRF-CMAQ model to evaluate the
regional air quality and climate impacts of future-year anthropogenic
emissions scenarios
Evaluate impact of two-way coupled WRF-CMAQ on regulatory
applications
Provide new emissions factors and chemical composition data
for dispersed sources of air pollutants, including off-road
vehicles (airplanes, ships, construction equipment) to directly
support State efforts to improve emissions inventories
Transfer data to OAR and the States on the chemical characterization
of carbonaceous PM as a function of particle size.
Enhance and update the SPECIATE database of emission profiles by
source category for air quality modeling and source-receptor modeling
applications
Transfer to OAR and the States improved PM and HAP emission
factors and chemical source profiles for commercial aircraft engines
Determine emission factors and characteristics of open burning of
agricultural fires and wild and prescribed forest fires for ozone, PM,
and HAPs
Characterize HAPs and other NAAQS-related pollutants from priority
off-road sources.
Identify emissions of regulated and unregulated pollutants during the
use of alternative fuels and fuel additives in on-road motor vehicles
Provide new and improved source-receptor based methods and
models, and associated input data (e.g., source markers) to better
quantify ambient concentrations and human exposure for coarse
and other PM size fractions, as well as related PM components
identified by health researchers as important.
Improve source apportionment through the development of enhanced
sampling and analytical methods and receptor-based models.
Evaluate and improve receptor modeling for PM source apportionment
Provide new and improved source-receptor-based models to quantify
the sources of coarse and other PM size fractions.
Evaluate exposures to sources of coarse and other PM size fractions
identified by health researchers as important.
Year Lead
Due Lab
2011
2011
2008
2009
2011
2010
2011
2011
2011
2011
2008
2008
2010
2011
2011
2011
2012
2012
2009
2011
2012
NERL
NERL
NERL
NERL
NERL
NERL
NERL
NERL
NRMRL
NERL
NRMRL
NRMRL
NRMRL
NRMRL
NRMRL
NRMRL
NRMRL
NERL
NERL
NCER
NERL
NERL
27
-------
LTG2
Air pollution research will reduce uncertainties in linking health and environmental outcomes
to air pollution sources to support effective air quality strategies.
This goal represents a major strategic change in the ORD's Clean Air Research program. It
envisions an approach to air pollution research that attacks the problem from a multi-pollutant
perspective, encompassing all aspects of air pollution from source to health outcomes. It brings
together three themes that are complementary and support one another and yet relate and expand
the two themes comprising LTG 1 (Figure 5). Following the two themes of LTG 1, the themes of
LTG 2 include: 3) launch a multi-pollutant research program to better reflect the nature of real
world air pollution; 4) develop a source to health outcome approach to more effectively address
air contamination, starting with the near-road issue; and 5) develop a framework for assessing
the health and environmental impacts of EPA regulatory activities (i.e., accountability). For each
theme, Table 3 aligns the APGs abbreviated as underlined phases within the narrative below.
Implementing LTG-2 within the program promotes leveraging of ORD research activities to
include under-funded goals within a broader framework, and more a logical orientation of the
Clean Air Research program with the recent reorganization of our major client office, OAQPS.
Theme 3: Develop a multi-pollutant approach to research
Air pollution is a complex mixture comprising hundreds of primary emission products and
secondarily transformed pollutants dispersed in ambient air. As such, in developing a multi-
pollutant research activity to address associated risks, there must be consideration of the inherent
toxicity of each constituent of the mixture, the likelihood of exposure to these constituents, and,
even more challenging, the potential interactions among these constituents (which, in the end,
may result from unique characteristics of toxicity or exposure because of these interactions).
From a health perspective, noncancer effects are seemingly dominated by just a few pollutants
(e.g., PM, ozone, CO, aldehydes) and, likewise, cancer effects involve specific classes of
polycyclic organic compounds, and select metals and organic vapors. Indeed, PM is itself a
complex mix with health impacts (both noncancer and cancer) that, to date, are best described as
associated with PM mass. However, it remains difficult to attribute health effect observations
completely to any single pollutant or class of compounds. Further, the evidence available to
evaluate hazard and dose-response is highly variable among pollutants, with human evidence
rarely available for the hazardous air pollutants whereas substantial human evidence is typically
available for the criteria air pollutants, resulting in greater uncertainty in characterizing potential
health risks from exposure to the HAPs. Additivity, antagonism, and potentiation have all been
observed with air pollutant mixtures, but because the phenomena are poorly understood,
regulation is, at present, best achieved by single pollutant regulations.
Like PM itself, the chemistry of the general air pollution mix is more complex than the mere
listing of the panoply of pollutants in ambient air. Many reactive gaseous and particulate
components emanate from varied sources, which, through complex atmospheric chemistries,
alter the atmospheric profile by consuming existent pollutants or creating new ones. Questions
exist as to how PM as a complex mix in and of itself should be treated. Total mass is the default,
28
-------
but as a measure composite mass is not necessarily robust across all health outcomes and end
points. Hence, questions are raised relative to what is known about the toxicity of mixtures. Co-
pollutants may interact chemically or may act through the exposed host altering his/her
sensitivity; much remains unclear. If PM (as a collage of primary source emissions and
secondary transformation products) and ozone (a gaseous product of atmospheric
transformations) have the most impact on health outcomes, what might be the most effective
strategy to minimize public health risk? Currently, measurement of PM only by mass regulates
all contributors equally. In contrast, ozone is measured as a singular end product even though
there are uncertainties remaining as to which source emissions are most significant in its
formation. These enigmas beg the question, Can air pollution controls be better focused on
sources from which the emissions are ultimately the most toxic?
The challenge is to design a research paradigm to foster a logical and relevant transition from a
single-pollutant research focus to a multi-pollutant approach, with the goal of controlling at the
source to optimize health risk reductions. Initially, ORD must develop an integrated multiple
pollutant research strategy (APG 16) that complements the goals and needs of ORD clients.
Traditionally, systematic approaches to the assessment of pollutant mixtures have either started
with a mixture and attempted to assess the driving components and/or interactions, or started
with the component parts and built toward the mixture. Both approaches have merit and
weaknesses and work best when used in a complementary, strategic manner. New "systems"
approaches offer some guidance but, as yet, have had limited influence on the air pollution
sciences. Part of any strategy, however, must involve deductive and inductive components. To
the former, the Clean Air Research program will include multi-city/multi-pollutant studies (APG
19) to establish a matrix of diverse source exposures from which component-driven health
impacts might be discerned. Epidemiological and toxicological studies will determine whether
adverse health outcomes are associated with the various exposure scenarios and PM source-
derived components. These data and findings can be compared with toxicology studies of
defined laboratory source emissions, as well as controlled exposures to concentrated air
particulates or other pollutants. Research will also be conducted to determine which sources and
components humans are actually exposed to across cities. Integrating information from studies of
specific sources and a hierarchy of associated toxicological potential, along with studies from
cities with differing source profiles, will refine the assessment of risk and the criticality of
pollutant type, character and source (integrated with findings from Theme 4).
Theme 4: Identify specific source-to-health linkages, using "near-roadway" as the prototype
Research clearly is needed to understand relationships among air pollutants (PM hazardous
components, co-pollutants, and HAPs) emitted from emission sources and the resulting ambient
concentrations and transformation products that may be involved in human exposures and
adverse effects. ORD will develop analytic methods and enhance models/tools to link health (and
where possible ecosystem) impacts to air pollution sources (APG 17). For example, methods to
identify which pollutant sources contribute to exposures need further refinement for routine
application to studies of health outcomes. Likewise, efforts need to be made to avail new
information resources, such as satellite data, and to develop statistical techniques that can
combine and integrate diverse data to improve ambient air quality and exposure estimates. This
issue will grow in importance as more is learned on air quality-climate interactions.
29
-------
As an initial focus for research on source-to-health linkages, ORD will address near-road
emissions, exposures, and related health risks from mobiles sources and evaluate risk
management options (APG 18). Near-road air pollution was selected as a central theme because
it is a problem that is of pressing ORD partner interest/need; requires integrated, multidisciplined
field and laboratory sciences; and allows the assessment the impacts of mitigation
(accountability; see Theme 5 below).
A growing number of health studies have identified adverse health effects, including respiratory
disease, cancer, and even mortality, for populations living near major roads. These initial reports
are raising concerns about the building of schools near roadways, the quality of indoor air in
existing schools near roadways, and the general health impacts on people living near roads. A
number of ongoing but somewhat disparate efforts regarding near-road environments already
exist within the ORD portfolio. A more directed near-road pilot research effort has been initiated,
with preliminary studies of near-road emissions, distance from road measurements, development
of local environment dispersion models, and assessments of low-cost mitigation strategies for the
indoor school environment. This research theme expands these efforts to determine the broader
significance of near-road emissions from varied traffic, vehicles, and conditions; potentials for
exposure and related health risks; and the development of tools for addressing the problem.
Other research approaches will also be undertaken to systematically evaluate linking air pollution
sources and components to health effects for specific sources (other than roadway) and single
geographic locations (APG 20). Research projects will include toxicological studies of source-
specific emissions, epidemiological studies in communities impacted by specific sources or
industrial sectors, and health and exposure studies in specific geographic locations impacted by
multiple sources. This approach dovetails with the multi-pollutant/multi-city studies underway or
planned within Theme 3. Research also will address methods for evaluating risk management
options in a multi-pollutant context. It is clear from existing research and the new sector-based
approaches being adopted by OAQPS that controls at the source targeting certain specified
pollutants typically reduce other emission components, many of which are also of concern.
Theme 5: Assess health and environmental improvements due to past regulatory actions
Assessing the effectiveness or impact of regulatory decisions (often referred to as
"accountability") on exposure and health is a complex and challenging undertaking. When a new
environmental regulation is issued, the changes necessary to achieve the regulatory objective of
improved public or environmental health are generally not instantaneous, so there is rarely a step
change in the outcome. Development of implementation plans, promotion and adoption of new
technologies or management strategies, and other activities all take place over an extended time
period. Even with the phase-out of lead from auto fuels in the 1970's, the reductions in exposures
and blood lead levels were not immediate, and even today vestigial lead (some from still
uncontrolled sources such as piston aircraft fuels) and re-entrainment from deposition sites
remain. During an implementation period, especially if extended over time, exposure and health
also may be affected by other factors such as changes health care practices, changes in lifestyle
(e.g., diet, smoking, obesity trends), or other changes resulting from regulatory or market forces.
Research is underway to develop methodologies that can address the complexities of assessing
30
-------
regulatory impacts. Several recent studies (intramural and from HEI) have suggested the
feasibility of such assessments.
As part of this research program, ORD intends initially to develop a framework for
accountability studies (APG 15). This in-house effort will be coordinated with related work
underway through HEI. A broader based accountability framework is being conceptualized
across ORD (centered in the HHRP), in which the Clean Air Research program effort is being
highlighted as a prototype because considerable thought and effort has been applied in concert
with OAQPS. As currently conceptualized, the Air accountability framework will provide
methods and examples for assessing the benefits and impacts of regulatory or other mitigation
activities. Initial efforts are underway to evaluate existing and emerging databases for potential
use, and prototypic models will be proposed for refinement and testing. ORD will be conducting
field studies to evaluate whether control technologies are achieving anticipated pollutant
reductions or resulting in unintended health and environmental consequences (APG21). Also,
ORD will coordinate with efforts initiated by other organizations with similar interests (e.g.,
NARSTO, which currently is developing an assessment document focusing on accountability in
air quality). By 2012, ORD plans to refine the Air framework and report on studies (intramural
and extramural partners) assessing the impact of actions taken to reduce air pollution (APG 22).
Table 3. APGs and APMs for LTG 2
APG 15
ARM 69
ARM 70
ARM 71
ARM 72
APG 16
ARM 73
ARM 74
APG 17
ARM 75
ARM 76
ARM 77
ARM 78
APG/APM Title
Develop a framework to assess the effectiveness of air pollution
regulations and control strategies in reducing human exposure,
ecosystem deposition, environmental and health impacts
Produce a conceptual Air Accountability Framework, including best
available indicators and linkage techniques
Develop a mesoscale pilot of approaches for identifying and tracking
regulatory impacts
As a principal sponsor and contributing author, report on NARSTO
Accountability Science Assessment
Report on studies assessing changes in air quality and health status
from actions taken to reduce air pollution
Develop an integrated multiple pollutant research program (MPP)
strategy
Multi-disciplinary workshop on developing a multi-pollutant research
program
Develop air multi-pollutant strategy
Develop methods and enhance tools to link health and
ecosystem impacts to air pollution sources, including remote
sensing and data combination techniques.
Develop and evaluate data combination techniques to improve human
and ecological exposure assessments.
Identify new biomarkers of exposure or effect related to air pollution
components or sources
Develop methods that provide more temporally and compositionally
refined measurements of air pollutants that can be used to improve
source apportionment analyses.
Develop, improve, and evaluate advanced measurement techniques
for SA of organic PM
2009
2009
2009
2009
2009
2009
2008
2009
2010
2010
2010
2010
2009
NERL
NERL
NERL
NERL
NCER
NPD
NPD
NHEERL
NPD
NERL
NERL
NHEERL
NERL
NCER
NCER
NRMRL
-------
APG18
ARM 79
ARM 80
ARM 81
ARM 82
ARM 83
APG19
ARM 84
ARM 85
ARM 86
APG20
ARM 87
ARM 88
ARM 89
ARM 90
APG21
ARM 91
ARM 92
APG/APM Title
Determine the significance of near-road emissions/exposures
and related health risks from mobile sources and evaluate risk
management options
Characterize "combustion-related emissions and components
(including volatile compounds)" and relate them to exposures and
health effects in near-roadway environments
Characterize how "mechanically-generated emissions" (including
urban coarse mode particles) relate exposures and health effects and
determine their relative toxicity in near-roadway environments.
Determine how specific school mitigation approaches influence
concentrations and exposures to near-roadway pollutants.
Evaluate and identify assessment tools to aid urban planners in
considering near-roadway health effects.
Provide information on the health effects and potential underlying
mechanisms associated with exposure to diesel exhaust particles
Conduct multi-pollutant, multi-city studies to evaluate the relative
associations of PM, components/sources of the mixture, and
gaseous co-pollutants, with key human health events in multiple
U.S. cities
Compile and analyze data on PM components from the speciation
trends monitoring network
Strengthen national air monitoring databases for use in health studies
Compare health risks associated with PM components, sources and
co-pollutants from locations across the U.S.
Investigate relationships between sources, exposures, and health
effects using a variety of approaches that focus on single
geographic locations or specific sources (other than roadway)
and identify options to reduce exposures for sources of concern
Apply source apportionment and exposure tools to support health
studies investigating effects associated with specific geographic
locations
Characterize susceptibility and health effects resulting from selected
sources of air pollution (other than roadway) and assess their relative
toxicity
Develop prototype model for evaluating integrated multi-pollutant
emissions reduction approaches for U.S. industrial sectors and provide
information on emissions and risk management options for key
sectors.
Provide test methods and protocols for the indoor environment to
assess proposed standards for aldehyde emissions and other air
toxics from composite wood products
Evaluate whether control technologies deployed for major
stationary and mobile sources are achieving the pollutant
reductions anticipated and whether these technologies are
having any unintended health and environmental consequences
Evaluation of existing data to determine the national-level performance
of control measures implemented under major EPA rules
Evaluate control measures for possible adverse unintended
consequences that impact human health and the environment
2012
2012
2012
2012
2010
2012
2010
2011
2012
2012
2012
2012
2009
2010
2012
2012
2012
Lead Lab
ORD
NRMRL
NERL
NHEERL
NCER
NHEERL
NERL
NRMRL
NERL
NERL
NCER
NCER
NCER
NCER
NCER
ORD
NERL
NCER
NHEERL
NCER
NRMRL
NRMRL
NRMRL
NRMRL
NRMRL
32
-------
ARM 93
Describe health effects or toxic properties of manufactured
nanoparticles intended for commercial use, pollution control, efficient
energy use, or applications to modify air pollutants regulated by the
Clean Air Act
2012
ead Lab
NHEERL
APG22
Refine the Air Accountability Framework through the use of pilot
or test-bed activities or related environmental opportunities for
proof of concept.
2012
NERL
ARM 94
Evaluate the progress assessment capability of the Air Accountability
Framework and incorporate improved indicators and linkage
techniques in an updated version
2012
NERL
ARM 95
Develop and apply prototype methods identifying and tracking the
regulatory impacts of CAIR
2012
NERL
ARM 96
Report on studies assessing the impact of actions taken to reduce air
pollution
2012
NCER
D. Linking Clean Air Research with other ORD Programs
The Clean Air Research program coordinates with other ORD programs to achieve the best
science and maximal leveraging of resources. The programs with which the Clean Air Research
program coordinates most closely include HHRP, HHRA, the Global Change Research program
(GCRP), the Mercury Research program, and the Ecological Research Program (ERP). The level
of program coordination varies considerably. Involvement ranges from that in strategic planning
and MYP development to coordination of specific program or research elements at the L/C level
where leveraged research activities might lead to more broadly applicable results and data.
Asthma exacerbation is an important issue to both the Clean Air Research program and HHRP.
The Clean Air Research program supports asthma research within its susceptibility theme
because the primary target organ system for air pollution is the lung and because of the clear
predisposition of asthmatics to exaggerated responsiveness to inhaled toxicants. Asthma research
is coordinated across both the Clean Air Research program and HHRP through coordinated
APGs and APMs, project funding activities, and a local invited speaker series. Research being
conducted to address asthma issues frequently involves humans and animal models exposed to
various air contaminants (e.g., PM, ozone, HAPs, molds - all of interest to OAR clients). These
studies provide data to assess susceptibility and basic modes of action that aid in extrapolation
and risk avoidance recommendations for at-risk groups. Co-sponsored exposure research has also
been applied to ambient pollutant environments to develop various receptor models used by risk
assessors. In that spirit, the Clean Air Research program and HHRP recently cosponsored an
intramural RFA to integrate the science and promote research coordination among asthma and
other related indoor air research activities. In addition, the programs have leveraged support to
studies assessing the health and environmental improvements resulting from past regulatory
actions.
The Clean Air Research program is linked to the HHRA program as both collaborator and as a
provider of information and support. As the HHRA program, located within NCEA, is charged
33
-------
with the responsibility of developing the NAAQS Integrated Science Assessments and IRIS for
the HAPs, they are dependent on the science information produced by the Clean Air Research
program for inclusion into their documents and assessments. The Clean Air Research program
has historically been the primary source of the NAAQS database and continues in that role. The
HAPs contributions to the HHRA program has been less substantive and limited to dose-
response model development for selected chemicals and toxicology information derived from
mixture studies that include related HAPs. The Clean Air Research program also serves as an
essential collaborator in document and workshop development and in the pursuit of core research
underlying risk assessment methods (e.g., pulmonary dosimetry models, mode of action models,
etc.). In their position as client, NCEA participates in the Clean Air RCT in setting priorities;
likewise NCEA functions within the Assistant Laboratory/Center Director advisory group to the
NPD in decision making and to ensure communication. The collaborative relationship between
these programs is long-standing and is a strength of ORD's overall air pollution research efforts.
Atmospheric mercury is clearly an issue of concern to the Clean Air Research program. At
present, this program is distinct from the Clean Air Research program because of unique EPA
interests. Nevertheless, although the size of the program is relatively small when compared to
Clean Air Research, actual mercury project planning and implementation are coordinated
through Clean Air Research-funded program areas because many of the analytical and modeling
tools overlap or are utilized similarly. Examples include specific coordinated projects to address
targeted questions regarding control technologies (e.g., the use of selective catalytic reduction),
and projects to monitor and assess mercury deposition and speciation in selected sensitive
environmental areas.
The Clean Air Research program historically has coordinated with the GCRP to better quantify
and understand factors that may have impacts on global climate and air quality. The recent U.S.
Supreme Court decision (No. 05-1120; Massachusetts et al. v. EPA)14 judged that EPA has the
authority to assess the "greenhouse gas" CO2 as an air pollutant. As such, EPA has initiated a
series of steps to evaluate CO2 from automobiles regarding potential "endangerment" to public
health and the environment. The Court's decision and subsequent activities on the part of EPA
forecasts changes in the assessment and potential regulation of CO2, which likely will have
implications regarding research in both the Global Change and Clean Air Research programs.
Expanded research and program integration is possible. However, interactions have been
ongoing. One example is research on emissions of elemental carbon, which recent evidence
shows may have important implications for climate change because of its ability to absorb solar
radiation. Other interactions involve the development of atmospheric models (such as CMAQ)
and climate models, which are now advancing to sufficient sophistication to begin to address
questions of air quality impacts on climate and vice versa. Tools are also under development to
evaluate future technology change and how this could impact future levels of CO2 and other air
pollutants of concern. The goal of this research is not only to assess these cross-impacts of air
quality and climate but to provide predictive tools for guidance to the policy directors and for
public communication (e.g., AIRNow). This portion of the program may well see substantial
change in the future.
Current coordination with the ERP is limited. Shifting program priorities and fiscal constraints
14 Decision: http://www.supremecourtus.gov/opinions/06pdf/05-1120.pdf.
34
-------
have taken the programs in somewhat separate directions over the past several years. However,
with recent changes in the ERP toward an "ecosystem services" focus, which relates more to
issues associated with the air-ecosystem interface, it is anticipated that common research areas
and activities will be identified for collaboration. Already in 2006-2007, the Clean Air Research
program funded a pilot in ecosystems assessment to examine sulfur deposition profiles and the
distribution of local acidification, in part as an accountability effort. Currently, the ERP is
undergoing major revision, and these coordination issues will be addressed more fully in future
MYP revisions.
E. Performance Assessment Rating Tool Long-Term Goals and Measures
Protection of public health and the environment from the adverse impacts of air pollution is the
ultimate goal of ORD's Clean Air Research program. Achieving this goal is neither easy nor
straightforward, given the complexity of anthropogenic and natural emissions and the potential
for human health impacts. Lying between emissions and health impacts is a complicated array of
atmospheric physicochemical processes and myriad human biological and behavioral factors that
affect exposure and response to and recovery from environmental stressors. OMB utilizes the
Performance Assessment Rating Tool (PART) as a means to periodically evaluate the progress
and efficiency of the Clean Air Research program in its efforts to achieve the goals of improved
air quality and reduced risk. The mission of PART is to establish clear measures and milestones
against which the program can be monitored and assessed regarding overall stewardship of the
public trust and progress toward outcomes that demonstrate or reflect benefit to the American
public.
The MYP is constructed around two LTGs toward which progress can be evaluated. Structured
under these goals are the APGs and APMs that provide products or building blocks, which, if
accomplished or achieved in a timely and efficient manner, can be used as one tool to evaluate
program progress and effectiveness. PART is clear on its distinction between program
"products" and "outcomes." In effect, although products (research findings, models, and tools)
are important to the science and the program, it is progress towards the outcome (public benefit)
that is most important. Table 4 lists the long-term and annual measures being used to assess the
Clean Air Research program.
35
-------
Table 4. PART Measures
Measure
Long-Term
Long-Term
Long-Term
Annual
Annual
Annual
Annual
Type of Measure
Outcome
Outcome
Output
Outcome
Output
Output
Output
Measure Language
Progress in assessing the linkage between health impacts and air
pollutant sources and reducing the uncertainties that impede the
understanding and usefulness of these linkages
Progress toward reducing uncertainty in the science that supports the
standard-setting and air quality management decisions
Percentage of program outputs appearing in the Office of Air and
Radiation's National Ambient Air Quality Risk and Exposure
Assessment
Percent improvement in customer satisfaction and product
usefulness survey score
Percent progress toward completion of a hierarchy of air pollutant
sources based on the risk they pose to human health
Percentage of program publications rated as highly cited papers
Percent of planned actions accomplished toward the long-term goal
of reducing uncertainty in the science that supports the standard-
setting and air quality management decisions
The Clean Air Research program must report to OMB PART its accomplishments as measured
against the annual and long-term goals, and every 4-5 years the Clean Air Research program
must undergo a full PART review to assess its long-term effectiveness. ORD has also developed
Program Improvement Plans that identify specific actions to be taken to improve performance.
For the Clean Air Research program, these include:
. Convene annual program reviews in which extramural expert discipline scientists and
clients will assess the state of ORD science, ensure progress toward outcome goals, and
determine the need for strategic mid-course adjustments to maximize program efficiency
and assist with out-year planning.
The program must develop at least one efficiency measure that adequately reflects the
efficiency of the program.
. Improve multi-year plan (MYP) and financial data tracking systems and procedures to
better and more transparently integrate grantee and program performance with financial
information.
. Develop an annual measure that more directly demonstrates progress on toward the long-
term goal of reducing uncertainty in identified research areas of high priority.
. Develop and implement adequate methods for determining progress on the program's two
new long-term measures (uncertainty and source-to-health linkage measures) as well as
for the new annual measure (customer survey measure).
For each of these elements, some action has been taken, but the overall goal has not been
completed.
36
-------
III. CONCLUSIONS
A. The Clean Air Research program supports OAR and other client-partners.
The Clean Air Research program provides critical science to science-users (i.e., NCEA, OAR) to
establish or refine the underpinnings of important regulatory decisions and public guidance. The
program also provides the tools and models along with the technical support needed to
implement these decisions in the field. These contributions derive from a science and
engineering platform that is regarded, both within EPA and internationally, as integrated and
high performing. Although the science has shown individual air pollutants have effects on health
and welfare, mixtures of air pollutants truer to the realities of ambient air have the potential to
interact in complex ways potentially altering its outcomes. As protection of public health is a
primary EPA goal, minimizing health impacts may be more effectively achieved by strategic
control of sources that contribute directly or indirectly to health outcomes. The potential value of
multi-pollutant approaches has been recognized by OAQPS in its organizational structure and
planning and as such, the timing is appropriate for the Clean Air Research program to make a
science investment in this area. ORD will formulate its multi-pollutant research program from a
source-to-health outcome paradigm. This paradigm is implicitly cross-discipline and integrated
and, as such, provides opportunities for more effective control strategies and positive impacts on
health.
B. Air research will evolve as a multi-disciplined, integrated endeavor founded upon the NRC
Priorities for PM as it builds upon the source-to-health outcome paradigm.
The current MYP lays out a strategy that serves the current regulatory mandate of EPA and
begins to move air pollution sciences that support regulatory decision-making to a more realistic,
yet more complex, multi-pollutant paradigm. The three historic Air research themes are now
organized into one Air program (Clean Air Research), although the impact return for PM
research supports it as a primary program focus. The NRC priorities have been invaluable in
organizing the PM research over the last decade and, as an approach, have been central in the
prioritization of the multiple needs of Clean Air Research program clients. It is clear that these
commitments to the NRC issues have been structured into the APGs and APMs as they relate to
PM, including assessments of hazardous components, particle size, effects of long-term
exposures, susceptibility, mechanisms, exposure assessments, atmospheric sciences,
implementation model and tool development, emissions and controls, etc. What has evolved is
the program vision to also undertake the challenge to link pollutant sources to their ultimate
health outcomes within a multi-pollutant construct. This construct will continue to evolve as the
MYP is implemented, and it will have multiple inputs from OAQPS as it develops its multi-
pollutant policy test beds, NARSTO as it finalizes its assessment of multi-
pollutant/accountability assessment document, and other client feedback. The near-road source-
environment has been established as the MYP prototype for implementing this paradigm. The
goal is better targeted and more efficient control and mitigation and improved public and
environmental health.
C. Future research issues are already emerging as current regulations, land use,
transportation, and climate change impact both local and regional air quality.
The Clean Air Research program is well positioned to address emerging air quality issues.
Adopting a multi-pollutant future, changes in regulation (CO2 impacts and controls) and climate-
37
-------
air quality interactions at the local and regional scales are already under study by ORD.
Intramural workgroups and STAR-supported projects (current awardees and planned RFAs)
provide the foundation for expanded research as this issue evolves over the next few years.
38
-------
Appendix A: Recent Program Accomplishments
ORD's Clean Air Research has a long history of responsiveness to client priorities, and
delivering relevant and useful products that support decision-making and policy implementation.
The report, "Paniculate Matter Research Program: Five Years of Progress" (February 2004;
referenced in footnote 8) summarizes notable PM-related achievements of the research program
from 1998, when PM became prominent issue, through 2002. That report was organized around
the 10 priorities noted earlier by the NRC (see footnote 5); a revised and updated ORD progress
report is scheduled for release in 2009. In this appendix, selected achievements since 2005 are
highlighted. This summary is not intended to be a complete overview but rather to provide
insight into program value. Since 2005, the Clean Air Research program has built on its previous
successes, with the goals of refining our understanding of the science necessary to reduce
uncertainties in decision-making and improving the tools needed to assess and implement policy.
The key to these advances lies in interdisciplinary science and integrated program execution.
This section will cite selected achievements from across the entire program, not just PM.
Because the Clean Air Research program is moving forward to a multi-pollutant framework, this
accomplishments overview is presented using the core paradigm shown below.
Source ^Atmospheric Transformation ^Exposure >Dose ^Health Outcome
Source
Emission characterization of prime sources contributing directly or indirectly to air pollution is
fundamental to the value of the source-to-health outcome paradigm. Not only does it serve to
reduce uncertainty in the development and implementation of effective mitigation or control
strategies, emission characterization serves to link health risks to gaseous or particulate
components, as well as to sources, with greater specificity. This goal was noted as high priority
by both NRC panels (Priorities and Air Quality; see page 3, footnote 5) and as fundamental to
integrated air quality assessments and to the development of appropriately targeted health-based
standards. In this regard, significant advances in updating and improving emission inventories
have been achieved on multiple fronts. Those sources pursued by ORD are generally not those
assessed by State regulatory units but are more generic and poorly characterized. For example,
diffuse sources are particularly problematic. Advancements in optical remote technologies have
yielded new data from varying types of biomass burning to livestock waste ponds. Optical
remote methods for precursor gases such as ammonia are not only important for general air
hygiene but allow refinements in atmospheric models where ammonia is a major assumption in
aerosol chemistry (e.g., acidity). Similarly, laser-based, time-of-flight instruments provide real-
time analyses of trace organics, including aromatics and PAHs, in dilute vehicle exhaust and
fugitive emissions. Engine emission characterizations from various vehicle types, such as idling
versus moving diesel school buses, have likewise undergone detailed study not only of mass
emissions but chemical speciation. Other sources heretofore not well characterized in the context
of their relative impact on ambient air, ranging from dispersed seasonal wildfires to point sources
such as airports, have begun to be characterized using analogous advanced optical and prototype
satellite-based technologies.
39
-------
Collectively, these data improve and update emission inventory databases maintained by EPA
(e.g., SPECIATE) on which comprehensive atmospheric models used in OAR and
State/Region/tribe implementation strategies (e.g., SIPs) depend. Advances in mobile source
emission characterization also serve on the science investigatory front mainly in the area of
sensitivity and response-time (e.g., deep UV differential optical absorption spectrometry - DUV
DOAS) and, as such, will be important in the developing near road research program.
Advances in control technologies have demonstrated effective reductions and removal of NOx
(most importantly NO2) and mercury (Hg°) from pilot plant coal-fired boilers. Refinements in
these technologies are critical as coal combustion grows nationally. These same pilot plant
operations have also been used for comparative emission toxicology studies and assessments of
physical and compositional attributes of PM emissions. Analogous diesel studies have revealed
significant compositional and toxicity variance. Real-world animal exposures to traffic emissions
(diesel and gasoline) have shown varying effects (from pulmonary to neurological) likely
because of varying concentration profiles and aging related changes in gases and particles. In
general, proximity to the roadway has yielded the most consistent responses. Across ORD
(intramural and extramural) there is increasing focus on source-based responses to ascertain
hierarchical toxicity patterns and compositional relationships.
Atmospheric Transformation
Once pollutants are emitted, it is important to understand how they interact with other
compounds present in the ambient environment. These transformations and interactions are
critical inputs for our air quality models and directly impact the types and concentrations of
pollutants the population is exposed to over time. Laboratory and field studies have made
substantial gains in our defining atmospheric chemistries that play significant roles not only to
achieve a better understanding of theses processes in ambient air but in refining the predictive
accuracy of complex multipollutant atmospheric models like CMAQ. Each year, one or more
upgrades of CMAQ is released for client as well as research use with the next major revision for
SIP development due in 2008. ORD investigators have refined or overhauled chemistry modules
that drive components of the model (e.g., photochemistry of mobile-source-derived aromatics).
Similarly, other studies have been able to discriminate dominant biogenic hydrocarbons from
other organics as critical drivers in ambient photochemistry. These refinements have advanced
our understanding of carbon, nitrogen, sulfur, and even mercury chemistries in CMAQ and
related but more specialized atmospheric models. The upgraded models are tested and validated
against real-world temporal and spatial measurements before release. Also, the CMAQ model
now has, for the first time, incorporated a new weather research and forecasting (WRF)
meteorological model that will be the foundation of future air pollution and climate predictive
models. As these models are multipollutant and are widely run for SIP development, ongoing
refinements, especially in the highly complex organic arena, have been critical to accuracy and
dissecting the relative prominence of the anthropogenic and biogenic (e.g., natural terpenes,
isoprene, etc.) contributions. With the growing use of ethanol and biofuels as alternative fuels
and the introduction of new additives with various functions, predictive models suggest changes
in atmospheric chemistry that may alter transformation product profiles.
Atmospheric models, such as CMAQ, are being asked to refine to smaller area grid sizes for
community application, to continually broaden the pollutant mix (e.g., HAPs have now been
40
-------
incorporated), and to attempt to tie to dispersion models in an effort to find innovative
approaches to couple with personal exposure models and, ultimately, health effect studies.
Intramural work is ongoing in collaboration with OAR and the STAR program scientists and
NCER-STAR has released an RFA to further develop these innovations. Linking across models
and data to achieve better risk estimates and provide predictive information that may be
amenable to AIRNow-like public broadcasting is an important goal of EPA.
Exposure
There have been marked gains in refining links between regional and local exposure metrics with
those that relate to personal exposures for PM and some of its attributes (most notably size).
Admittedly, less has been gained regarding co-pollutant exposures, although there are improved
exposure measures for some HAP compounds. In the case of PM, comprehensive field studies
have been conducted to evaluate the performance of sampling methods for measuring the coarse
fraction of PMio in ambient air. These have been conducted in several venues across the United
States as part of the Federal Reference Method (FRM) development project. This FRM is
complete and is being deployed by states. At the other end of the size spectrum, recent concerns
regarding traffic exposures have prompted exposure profiles for ultrafine PM emissions relative
to distance from roadways. There now exist some measures that tie to freeways, traffic volume
and vehicle type. ORD has particular interest in the effect of various mitigation methods,
especially as they relate to indoor penetration values. Building type and ventilation appear to be
major factors in penetration of ultrafine and coarse mode PM, as well as oxidant gases, but
appear to be less significant (on a relative basis) for fine PM and less reactive gases. Individuals
considered "susceptible" because of age or pre-existing disease appear to have exposure profiles
similar to those without susceptibility risk factors, with central monitors appearing to provide
reasonable estimates of fine PM exposure for the associated population. Not inconsistent with
this evidence for refined exposure metrics, a recent study in Los Angeles has demonstrated that
increasing the areal density of monitoring can reveal neighborhood-by-neighborhood differences
in health outcomes. These findings suggest greater PM risks than previously appreciated with
regional monitors. On the other hand, this was not clear in New York City, leaving this
provocative question to be further explored.
A large, multiyear, multi-season exposure study conducted in Detroit has completed its data
collection (winter 2007) which is being compiled into databases for estimation of source-
attributable exposures, regionally, locally, and indoors across the Detroit urban landscape. New
speciation methodologies for organics have been developed and are yielding data refining PM2.5
composition and its source links. These advancements should help refine existing receptor (e.g.,
SHEDS) and source apportionment models (e.g., UnMix) now in wide use but that have large
uncertainties. Related intramural and leveraged health studies in asthmatic children and adults
with cardiovascular disease in the Detroit area will yield refined risk estimates and better source
attribution. As noted above, when coupled with the concept of developing linkages with
atmospheric and receptor models that can track to the human effect level, clients will be able to
better assess the impact of source-oriented mitigation strategies.
41
-------
Dose
Exposure estimates are inherently inaccurate biometrics for human dose. Variation in dose from
individual to individual is often responsible for perceived biologic variability. Comparative
dosimetry is also important in linking the toxicological databases from animal toxicology to the
human condition. Dosimetry, when coupled with biological differences (e.g., species, pre-
existing disease, age) and variable exposure scenarios (e.g., exercise, lifestyle, co-exposures),
contributes to the uncertainties in final risk assessments. New findings with PM size modes in
subjects with lung disease augment what has long been known in healthy individuals - that PM
size is the major determinant to deposition profiles in the respiratory tract. Fine PM penetrates
more deeply into the lung than coarse PM but recent human data shows that although ultrafine
PM deposits penetrate the lung in large numbers per given mass, the deposition pattern in a
within the lung was not unlike that of coarse PM. In other words, large numbers (and more
relative mass) of ultrafine PM deposit in the airways and, therefore, ultrafine PM should not be
considered a risk only for the deep lung. With regard to fine and coarse PM, but less so with
ultrafmes, individuals with airway disease show increasing heterogeneity in deposition with
evidence of "hot spots" at airway bifurcations. Locally high doses of PM to lung tissues may
result and may determine the degree of damage to that region and may well account for the
exacerbation of responses (because of the higher dose) noted in people and animal models with
pre-existing lung diseases (e.g., asthma, COPD).
There is also related evidence that solubilized components of fine PM (e.g., metals and polar
organic compounds) permeate through the lung and distribute systemically, perhaps impacting
the cardiovascular and other organ systems. Ultrafine particles, associated with combustion
processes, may themselves also penetrate through lung tissues and move systemically by evading
normal defense systems that remove larger particles from the lung surface. Given the concerns of
traffic exposure and the predominant ultrafine PM profile near roadways, associations of health
outcomes with traffic have been linked hypothetically to ultrafmes, although research on co-
pollutants and other road products continues. Studies also show that various organic compounds
(through adsorption) associate with PM and can be transported deep into the lung. Once
disassociated from the particles, these materials can act locally or distribute systemically within
the exposed organism. Thus, health outcomes may reflect the inherent toxicities of particles and
their co-associated materials.
Health Outcome
ORD-supported research has established the backbone of our understanding of air pollution
health outcomes. In the PM arena, specifically, more than 40% of the research citations in the
Criteria Document (called the Integrated Science Assessment for the NAAQS currently under
review) and the Staff Paper (now called the Policy Assessment in rule decision-making) were
ORD-supported products. Currently, PM maintains its distinction as that air pollutant most
widely considered to pose a significant and widespread public health threat. A spectrum of
epidemiological studies, including various observational and panel studies, show relatively
consistent risk estimates for mortality in around the country, especially with regard to pulmonary
and cardiac health impacts. Morbidity, as reflected in a wide range of end points or responses
(e.g., hospitalization, school absenteeism) also relates to PM. An ever increasing group of
outcomes now associate with PM, and in some better still when combined in analyses with its
co-pollutants - infection, lung growth retardation, infant birth weigh and cardiac structure.
42
-------
Cardiovascular-related mortality in adults, however, appears to be strongly related to PM
exposure, both in terms of acute mortality risk as shown in a large study of older women as well
in the general population. Additionally, a study of Medicare data for 11.5 million people living in
204 urban counties in the United States found region-specific differences between the eastern
and western halves of the country when assessing hospital admission rates for cardiovascular and
respiratory diseases. In the Northeast, cardiovascular dysfunction can be related temporally to
PM exposures even within a few of the day. Interestingly, however, the Northwest, which is
dominated by wood smoke emissions in the winter, did not show straightforward links between
PM mass and cardiovascular events. As such, it appears that not all sources have similar impacts
on cardiovascular functions. As already noted, refinement of spatial exposure metrics through
more densely distributed monitors led to the discrimination of neighborhood-to-neighborhood
differences in PM mortality in Los Angeles. It also appears that reductions in major industrial
sources that contribute substantially to local and regional PM levels result in reductions in
mortality and morbidity. Hence, sources do appear to vary in their potencies, and it may well be
the mixtures (PM components and with co-pollutants) that drive the differences in response.
Collectively, the epidemiological findings are ever more strongly suggesting that there exist
significant susceptibility factors in responses, including age (perhaps linked to greater
exposures), syndrome complicated with cardiopulmonary impairments (e.g., diabetes), asthma
(notably in children), and COPD or heart disease (especially in the elderly with congestive heart
failure), as well as in selected genotypes. In the last case, the ability to withstand oxidant
challenge may well be a survival factor, and those lacking certain genes (e.g., GST-MI) may
have impaired antioxidant or related defenses. On the other hand, real-world exposures to
healthy highway patrol officers suggest that components of complex roadway emissions (gases
and particles, including metals) also show evidence of cardiac dysfunction.
Animal studies show analogous patterns of response and susceptibility, and strongly suggest that
oxidative stress plays a role in the toxicity of PM. A role for oxidant pathways is largely borne
out in in vitro studies. Markers of oxidant stress appear to tie to progression of diseases (e.g.,
atherosclerosis) in rodent models exposed to various PM (concentrated ambient particles [CAPs]
and combustion emissions). Cardiac dysfunction in diseased animals has been seen with roadway
emissions (mainly ultrafine) and combustion particles enriched with metals. Studies of CAPs in
humans and animals show a more variable pattern of cardiac responses that do not always
parallel the panel studies suggesting that the complexities of exposure (e.g., a role for co-
pollutants) and biologic scenarios are important modifiers of response. Hence, although there
appears to be credible evidence of health effects associated with PM, these are difficult to fully
reproduce under controlled conditions, perhaps because of the lack of co-pollutant interactions.
Similarly, compositional correlates are not always discernable. The likely involvement of
multiple components in varied adverse health outcomes argues that the most effective means of
study and control will emerge from source-oriented analyses. What does seem consistent from
collective assessment is a likely critical role for oxidant stress, perhaps at various levels of organ
and cellular bio-pathways, and that individual variability arises, at least in part, from
susceptibility (inclusive of dose, frailty, and genetic determinants that may impart adequate
defense).
43
-------
vvEPA
United States
Environmental Protection
Agency
PRESORTED STANDARD
POSTAGE a FEES PAID
EPA
PERMIT NO. G-35
Office of Research and Development (8101R)
Washington, DC 20460
Official Business
Penalty for Private Use
S300
Recycled/Recyclable Printed on paper that eontatm a mmimum of
50% posttomumer fiber content pm
------- |