EPA-600/3-77-080
1977 Ecological Research Series
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Office of Research and Development
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Researclr Triangle Park, North Carolina 27711
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U S. Environmental
Protection Agency, have been grouped into nine series These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields
The nine series are-
1 Environmental Health Effects Research
2 Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6 Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8 "Special" Reports
9 Miscellaneous Reports
This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
cies, and materials Problems are assessed for their long- and short-term influ-
ences Investigations include formation, transport, and pathway studies to deter-
mine the fate of pollutants and their effects This work provides the technical basis
for setting standards to minimize undesirable changes in living organisms in the
aquatic, terrestrial, and atmospheric environments
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/3-77-080
August 1977
AEROSOL RESEARCH BRANCH
ANNUAL REPORT FY 1976/76A
Edited by
William E. Wilson and Christine Danskin
Atmospheric Chemistry and Physics Division
Environmental Sciences Research Laboratory
Research Triangle Park, North Carolina 27711
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
T ~ ' -. •• f
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DISCLAIMER
This report has been reviewed by the Environmental Sciences Research
Laboratory, U.S. Environmental Protection Agency, and approved for
publication. Mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
ii
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ABSTRACT
The research program of the Aerosol Research Branch includes research
grants and contracts at institutions in many parts of the United States, in
addition to an intramural program. The purpose of these projects is to
study the chemical and physical properties of aerosols, identify the mecha-
nisms of aerosol formation and removal, and conduct experiments to measure
these rates.
The results of the research are being used (1) to establish the contri-
bution of the various sources to the ambient atmospheric aerosol loading,
(2) to characterize urban, natural, and primary and secondary aerosols, (3)
to develop quantitative descriptions of the generation and removal rates
associated with each major aerosol source and sink, (4) to quantify the
effects of aerosol on atmospheric chemical reactions, and (5) as a scientific
basis for recommending regulatory actions concerned with air quality
improvements.
In addition to base funding through EPA's Office of Research and Develop-
ment, the Aerosol Research Branch (ARB) also receives funds from the Federal
Interagency Energy/Environment Research and Development Program. This pro-
gram is coordinated by the Office of Energy, Minerals, and Industry, Dr.
Steven Gage, Deputy Assistant Administrator. The tasks conducted by ARB
under this program relate to the transport and fate of pollutants associated
with energy sources.
Tasks funded by the Energy/Environment program are not described in this
report but are listed by title and principal investigator. The FY 1976/76A
annual report of the energy program is found in EPA Report 600/7-77-076,,
iii
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CONTENTS
Abstract , »
Abbreviated Functional Statements ix
Acknowledgements x
1. Introduction 1
2. Summary of Aerosol Research Branch Fiscal Year
1976 Program by Project 2
3. Project Reports
A. ATMOSPHERIC PROCESSES AND EFFECTS
1. Aerosol Formation, Growth, and Removal
Formation of Atmospheric Aerosols—Parametric
Measurement of Submicron Atmospheric Aerosols,
by K.T. Whitby 4
To Investigate the Atmospheric Contribution of
Biogenic Sulfur to the Urban Load of Sulfur
Aerosols, by D.R. Hitchcock 8
Experimental Study of Aerosol Formation
Mechanisms in a Controlled Atmosphere, by
D.L. Fox 11
Formation of Atmospheric Aerosols—Smog
Chamber Research, by K.T. Whitby 13
Smog Chamber Study of Sulfur Dioxide Oxidation
and Aerosol Formation Mechanisms, by W.C. Kochmond. 14
Study of Vapor Pressure of Systems Forming
Atmospheric Aerosols, by G. Brown 16
Formation of Atmospheric Aerosols—Size
Distribution Models for Atmospheric Aerosols,
by K.T. Whitby 17
Aerosol Dynamics, by J.R. Brock 24
Biogenic Emission of Aerosol Precursors, by
L.L. Spiller 28
Metal Sulfite Complexes, by D. Lawing 29
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2. Aerosol Characterization and Sources
Sources and Trace Metals in Urban Aerosols.
Sub-Task Title: Urban, Non-urban, and Marine
Aerosol Studies, by J.W. Winchester 31
Relationship of the Smog Aerosol to Pollution
Sources, by S.K. Friedlander 36
A Study of the Identify and Sources of
Atmospheric Aerosols, by R.G. Draftz 38
Analysis of Air Pollutants by Mass Spectroscopy,
by A.L. Crittenden 40
Chemical Characterization of Model Aerosols,
by D. Mendenhall 42
Sources and Trace Metals in Urban Aerosols.
Sub-Task Title: Aerosols Properties Relevant to
Health Effects, by J.W. Winchester 46
Aerosol Sources Program, by R.K. Patterson 50
Aerosol Microscopy, by J. Gerhard 51
Field Expedition to Phoenix, AZ, by J.L. Durham ... 52
Analytical Support for Aerosol Studies, by
R.K. Patterson 53
3. Visibility and Radiation Effects
Optical Effects of Atmospheric Aerosol, by
A.P. Waggoner 55
4. Heterogeneous Reactions
The Role of Gas-Solid Interactions in Air
Pollution, by H.S. Judeikis 58
Structure and Reactivity of Adsorbed Oxides of
Sulfur and Other Small Sulfur-Containing
Molecules, by J.H. Lunsford 62
Structure and Reactivity of Adsorbed Oxides
of Sulfur, by J.H. Lunsford 65
Reactions of Sulfur Dioxide in Aerosols, by
D.M. Himmelblau 69
Mass Transport Models, by J.H. Overton 70
vz
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5. Technique Development
Formation of Atmospheric Aerosols—Nonideal
Characteristics of Impactors, by K.T. Whitby ... 76
Sources and Trace Metals in Urban Aerosols.
Sub-Task Title: Development and Application
of Analytical Sampling Techniques, by J.W. Winchester 78
Formation of Atmospheric Aerosols—Development
of a Sulfur Aerosol Analyzer, by K.T. Whitby ... 82
Simultaneous Comparison of the EAA and the
Diffusion Battery for Atmospheric Aerosol, by
J. Bricard 83
Determination of Sulfate Ion Concentrations in
Human and Animal Serum using High Pressure Liquid
Chromatography, by L.L. Spiller 84
Comparison Study of Data Collected with the
Dichotomous and High-Volume Samplers, by
T. McCarthy 85
A Cyrogenic Procedure for Concentrating Rating
Trace Gases in the Atmosphere, by L.L. Spiller. . . 86
Collection of Atmospheric N0~ by Treated
Filters, by L.L. Spiller 87
Instrumentation for Monitoring Meteorological
Data, by L.L. Spiller 88
Improvement of "Streaker" Technique for Automated
Appendices Collection and Analysis of Aerosols,
by W. Nelson 89
B. AUTO EXHAUST CATALYST PROGRAM
Roadway Aerosol Studies during General Motors
Sulfate Dispersion Study, by E.S. Macias 91
Formation of Atmospheric Aerosols—Aerosol Size
Distributions and Concentrations Measured During
the General Motors Sulfate Study, by K.T. Whitby . 94
Sources and Trace Metals in Urban Aerosols.
Sub-Task Title: Freeway Aerosol Studies, by
J.W. Winchester 100
Dynamics of Automotive Sulfate, by J.R. Brock .... 104
VII
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The General Motor-Environmental Protection Agency
Sulfate Dispersion Experiment in October 1975
at the General Motor, Milford Test Track, by
L.L. Spiller 106
Atmospheric Behavior of Catalyst-Generated
Aerosols from Source to Receptor, by J.L. Durham . 107
Appendices
A. List of ARE Projects funded by the Federal Interagency
Energy/Environment Research and Development Program
(Titles and Principal Investigator) Ill
B. Publications, Presentation, and Theses Listing 113
C. Publications, Presentations, and Theses Listing Index . . 127
Vlll
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.. ABBREVIATED FUNCTIONAL STATEMENTS
The Environmental Sciences Research Laboratory (ESRL) conducts research
programs in the physical sciences to detect, define, and quantify the effects
of air pollution on urban, regional, and global atmospheres, and the sub-
sequent impact on air and water quality and land use. ESRL is responsible
for the planning, implementation, and management of research and development
programs designed to quantitate the relationships between emissions of
pollutants from all types of sources, air quality, and atmospheric effects.
ESRL also plans, implements, and manages a research and development program
to provide needed techniques and instrumentation for the measurement and
characterization of pollutants in the ambient air and in the emissions from
all types of sources. ESRL's research and development program consists of
grants, contracts, and in-house work.
The Atmospheric Chemistry and Physics Division (ACPD) conducts research
programs (1) to characterize the chemical and physical properties of ambient
air pollutants and (2) to relate quantitatively the chemical and physical
properties of emissions from mobile, stationary, and natural sources to the
effects on air and water quality and land use. ACPD also develops techniques
and instrumentation for the measurement and characterization of gaseous and
aerosol pollutants.
The Aerosol Research Branch (ARB) studies the chemical and physical
properties of aerosols, identifies the mechanisms of aerosol formation and
removal, and conducts experiments to measure these rates. The properties
of atmospheric aerosols are related to health and welfare effects for the
purpose of selective control of pollutant sources.
ix
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ACKNOWLEDGEMENTS
The program of the Aerosol Research Branch is under the scientific
direction of A.P. Altshuller, Director, Environmental Sciences Research
Laboratory. EPA funds are provided through OALWU, Thomas Murphy, DAA
(Transport and Transformation Program) and OHEE, Delbert Earth, DAA
(Catalyst Program). Federal Interagency Energy/Environment Research and
Development Program funds (Project MISTT) are provided through OEMI, Steven
Gage, DAA. We also thank Robert Papetti and Deran Pashayan, OALWU, and
Greg D'Alessio, OEMI, for management support.
x
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1. INTRODUCTION
The Aerosol Research Branch (ARE), as part of the Environmental
Sciences Research Laboratory of the U.S. Environmental Protection Agency,
administers an extramural research program consisting of grants and contracts
at institutions in many parts of the United States. In addition to the
extramural program, ARE conducts a modest in-house program. Since the major
responsibility of ARB is to conduct an extramural research program, the
in-house program is designed to support the extramural program. It has three
major functions: 1) to provide rapid-response capability to respond to
agency needs, 2) to test out concepts prior to establishing extramural pro-
grams, and 3) to maintain the scientific competence of the EPA project
officers. It is considered extremely important that the scientific competence
and reputation of ARB's project officers be such that grant and contract
principal investigators consider them as scientific peers rather than funding
clerks.
This progress report presents results of tasks active during fiscal
years 1976 and 1976A. The reports have been classified into projects as
shown in the Summary of Aerosol Research Branch Fiscal 1976 Program by
Project. ARB tasks funded through the Federal Interagency Energy/Environment
Research and Development Program are listed by Title and Principal Investi-
gators in the Appendix. The Appendix also includes a Publications, Presenta-
tions, and Thesis Listing. The Publications List includes only EPA funded
research authored by the investigators funded through the Aerosol Research
Branch. Following the listing is an Authors Index. To find a particular
author's work in the Publications List first find the author's name in the
Index and then turn to the Publications List.
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2. SUMMARY OF AEROSOL RESEARCH BRANCH
FISCAL YEAR 1976 PROGRAM BY PROJECT
Project MISTT (Midwest Interstate Sulfur Transformation and Transport)
A study of pollutant transformations and removal during atmospheric
transport over various scale lengths.
Urban scale (50 km): Tracer and portable chamber studies.
Power plant plumes (250 km): Aircraft measurements.
Urban plumes (500 km): Aircraft and ground measurements.
Blobs (2000 km): Weather Service visibility reports and a ground
network of 14 stations extending from eastern Kansas to
New England.
Model Development and Data Analysis.
Funded by the Federal Interagency Energy/Environment Research and
Development Program through USEPA, ORD, OEMI. Program Element 1NE625.
Auto-Exhaust Catalyst Program
Determination of chemical and physical properties of sulfuric acid
aerosol produced by automobile catalysts.
Funded by USEPA, ORD, OHEE. Program Element 1AA601.
Atmospheric Processes and Effects
Aerosol Formation, Growth and Removal. Identification of physical and
chemical mechanisms for aerosols processes in the atmosphere, measurement
of important rate constants, and development of models for formation, growth
and removal of atmospheric aerosols.
Aerosol Characterization and Sources. The utilization of physical
properties, elemental and chemical analyses, and microscopy for the charac-
terization of atmospheric aerosols and the use of this information to
determine the primary and secondary source contributions to urban pollution.
Visibility and Radiation Effects. Measurement of pertinent aerosol
properties and determination of relationships between concentration, com-
position, size and effects.
Heterogeneous Reactions. Measurement of the rates and mechanisms of
reactions involving gases with surfaces or condensed phases.
Technique Development. Development of new instruments or techniques
required for the aerosol research program.
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712.
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A. ATMOSPHERIC PROCESSES AND EFFECTS
1. Aerosol Formation, Growth, and Removal. Identification of
physical and chemical mechanisms for aerosols processes in the atmosphere,
measurement of important rate constants, and development of models for
formation, growth and removal of atmospheric aerosols.
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712.
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1. Task Title: Formation of Atmospheric Aerosols - Parametric Measurement
of Submicron Atmospheric Aerosols
2. Objective:
To develop and validate a method for calculating the submicron
size distribution of atmospheric aerosols from three integral measure-
ments on the aerosol, namely, concentration nuclei count, electric
charger current, and the response of an integrating nephelometer.
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: W.E. Wilson
5. Progress:
Studies by G.M. Sverdrup were conducted in order to determine how
many aerosol parameters must be measured to adequately specify the
number, surface, and volume weightings of a submicron atmospheric aerosol
size distribution. A constraint placed upon the instrumentation was
that all instruments must operate in a continuous mode. This eliminated
the need for bag samples in order to accommodate instruments' long
sampling periods.
A minimum of three instruments (e.g., condensation nuclei counter,
aerosol charger, and nephelometer)'are necessary to obtain significant
information about the entire submicron size spectrum. Figure 1 shows
the sensitivities of the three instruments as a function of particle
size for a family of size distributions. The areas under the three
curves are equal to the total number concentration (N), the total current
from the charged aerosol (I) and the aerosol light scattering coefficient
(bsp). The nuclei counter and aerosol charger sensitivities were
experimentally determined. The nephelometer sensitivity was calculated
from Mie theory.
The submicron size distribution was determined by calculating the
expected values of N, I, and bsp, using a bimodal log-normal size distri-
bution model. Three of the log-normal function parameters were held
fixed while the other three were varied. The difference between the
theoretical and measured values of N, I, and bsp were minimized until
these differences were within the instrument uncertainty for all three
instruments.
Figure 2 shows plots of a comparison between the size distributions
obtained from the minimization procedure and the measured size. The
difference in total number concentration is zero due to the minimization.
The difference in total surface concentration is 0.4%, in total volume
13%. These differences are due to instrument uncertainty.
6. Publications, Presentations, Theses:
1. Sverdrup, G.M. Parametric Measurement of Submicron Atmospheric
Aerosols. Ph.D. Thesis. Submitted to: Mechanical Engineering Depart-
ment, University of Minnesota. November 1976.
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7. Plans:
1. The procedures developed In this task will be applied to data
acquired during the 1976 summer MISTT projects. The results will be
compared with actual size distributions measured with the Minnesota
Aerosol Analyzing System.
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1. Task Title: Investigate the Atmospheric Contribution of Biogenic
Sulfur to the Urban Load of Sulfur Aerosols
2. Objective:
To investigate the atmospheric contribution of biogenic sulfur
to the urban load of sulfur aerosols.
3. Institution: Hitchcock Associates
Investigator: Diane Hitchcock
4. EPA Project Officer: L.L. Spiller
5. Progress:
The existence of "natural" biogenic sulfur contributions to the
atmosphere has been recognized for some time, but estimates of the
strength of these natural sources or their distribution is virtually
unknown. Little useful information exists for assessing the claim
that biogenic S sources can contribute significantly to the load of
gaseous or particulate S in urban sites, or to the non-urban load
("background" level).
Many biological processes produce volatile sulfur compounds, and
may be responsible for biogenic S emission. The most important of
these processes appears to be the metabolism of the bacterial sulfate
reducers—chiefly of the species Desulfovibrio desulfuricans. These
organisms are obligate anaerobes and inhabit aquatic environments
where oxygen is absent. They use dissolved sulfate as a source of
oxygen in the oxidation of available organic matter, producing H?S
as a metabolic by-product.
H?S production by bacterial sulfate reducers may proceed at an
extremely rapid rate under suitable conditions. Field studies and
laboratory experiments show that rates of 50 to 100 metric tons per
km^ per yr may be common in suitable habitats. But no quantitative
data exist, and very few measurements have been made of atmospheric
sulfides near sites where sulfate reduction is active.
Included are preliminary results of a field study designed to
survey the distribution of atmospheric biogenic sulfur compounds near
sites where they are produced.
Atmospheric reactive sulfides and sulfur dioxide were measured in
a tidal marsh near Morehead City, North Carolina. AgNOo and LiOH
impregnated mi Hi pore filters were used for collecting the samples,
and analyzing for elemental S by means of X-ray fluorescence spectro-
scopy. Sample collection intervals of 12, 6, and 4 hours were synchro-
nized with tidal movements in order to observe the relationship between
exposure of the heavily organic H^S-rich muds at low tide, and the level
of sulfide in the atmosphere. Similarly synchronized 12 and 6-hour
samples were collected at a control site, a two-story building roof top
on the shore of Bogue Sound, approximately 1.5 miles from the marsh site.
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Sulfide levels in the marsh averaged 4.6 ppb over the 13-day field
study. A strong dependence on the tidal cycle was revealed by the 4-hour
samples taken at successive high and low tides. Sulfide was rarely
detected during high tide, and did not exceed 2 ppb. Low-tide levels
ranged from 2 to 57 ppb and averaged 10 ppb. The highest levels were
observed at night when local wind movements were minimal. At night,
the 10-tide sulfide levels averaged 5.5 m sec-1. Attempts to detect
sulfides in the air at the control site were generally unsuccessful.
Of 26 12-hour samples, only 4 showed detectable levels of sulfides, and
these did not exceed 1.5 ppb. (Fig. 1)
A second set of measurements was made in November to determine
whether biogenic S is present in the atmosphere at sites where no f^S-rich
muds are exposed during the tidal cycle, but where reducing sediments
occur under water. Measurements were made for 24 and 6-hour intervals
at 3 sites, 25 to 30 miles from any sources of anthropogenic SOp. One
of these sites is at the Coast Guard Station at Bogue Inlet on Bogue Banks,
and the others are a few miles north on White Oak River. Sulfide-rich
muds occur at both the latter sites, but are never exposed by the tide.
No sulfide-rich muds occur near the Coast Guard site, but some exist
inside the sound. (Water from the sound passes through the inlet four
times daily, and it may contain h^S derived from bottom sediments).
The results showed higher levels of atmospheric sulfur than originally
anticipated, with sulfide levels ranging from 0.5 to nearly 5 ppb; S0£
ranged from below detection limits to over 20 ppb. The means were
1.5 to 1.9 ppb sulfide: 4.5 to 4.8 ppb SOp. Wind speeds were usually
very high, and temperatures abnormally cold for this time of year. The
atmospheric S is biogenic, and we infer that it is derived from the
marine muds near the monitoring sites, although fresh-water swamps in
surrounding woods cannot be ruled out.
6. Publications, Presentation, and Theses: None.
7. Plans:
1. This survey will be repeated and extended with the following changes
in measurement procedures:
a) sulfide measurements with durations from one to two hours; b) measure-
ments of S0£ by means of a Meloy #FA-285 at best possible sensitivity
(1 ppb), with short integration time (2 sec.); c) measurement of ozone
and possibly other potential oxidizers.
2. Studies will be conducted at the same sites as in 1976 and at a new
site. The new site will be a brackish water site further inland, with
little tidal flushing and less sea water sulfate.
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16
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HIGH TIDE
Figure 1. (Note - These numbers are 5 ppp., 0,15 ppb and 1.4 ppb)
10
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!• Task Title: Experimental Study of Aerosol Formation Mechanisms in
a Controlled Atmosphere.
2. Objective:
To conduct experiments in a large outdoor chamber to obtain data
for modeling purposes on aerosol formation mechanisms from chemical
systems containing sulfur.
3. Institution: University of North Carolina at Chapel Hill, Chapel
Hill, North Carolina
Investigator: D.L. Fox
4. EPA Project Officer: J.L. Durham
5. Progress:
An investigation of photochemical systems containing hydrocarbons,
oxides of nitrogen, and sulfur dioxide has been conducted with the use
of a long-path infrared (LPIR) -fourier transform spectrometer (FTS).
This instrument has been successfully operated in situ in the outdoor
chamber and has provided the analytical capability to measure gas
phase product concentrations of some species not ordinarily measured
in smog chamber experiments (e.g., formic acid and peroxyacyl nitrate).
In propylene, NO^and S02 systems, SOp oxidation increases during the
N0-N02 crossover region; the same region where modeling predicts an
increased flux of free radicals to be present. Computer modeling of
these systems has been improved by knowledge of the product concentra-
tions measured through the course of an experiment by the LPIR-FTS
system.
In the presence of sunlight, sulfur dioxide in ambient air will
be oxidized to form sulfuric acid aerosol. One mechanism in this
conversion process is thought to be hydroxyl radical (OH) attack on
S02, which results in the formation of H2S04 vapor. Then the acid
vapor either condenses on existing particles or nucleation of new
particles occurs in the presence of water vapor. Results from the
outdoor chamber show the occurrence of both of these gas-to-particle
conversion mechanisms under certain conditions. When S02 in background
air is subjected to sunlight of variable intensity, fluctuations in the
condensation nuclei count correspond to variations in sunlight intensity
caused by clouds temporarily blocking the sun. Measurements of particle
size distribution as a function of time, show the formation of fine
particles as the intensity of sunlight increases rapidly. These observa-
tions are consistent with the hypothesized OH attack on S02- Hydroxyl
radical concentrations will vary with changes in light intensity. When
S02 concentrations are changing very slowly with time, the conversion
rate is primarily dependent on fluctuations in OH concentration.
The activity of H2S04 in the gas phase controls the pathway for gas-
to-particle conversion. At a certain level of activity H2S04 will
nucleate even in the presence of existing particle surface area. This
phenomena has been observed with rapid changes in sunlight.
11
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Aerosol samples have been collected on glass fiber and membrane
filters, and elemental analysis of the collected particles have been
performed using X-ray fluorescence. The X-ray fluorescence data and
the data from an electrical aerosol analyzer allow estimation of the
composition of the evolving aerosol as a function of time, relative
humidity and other parameters of interest. Comparison of the mass
of sulfur appearing in the aerosol particles with that lost from the
gas phase also is an aid in the determination of the sulfur budget for
the environmental system. Since X-ray fluorescence is non-destructive,
further analysis of the same samples is possible, thus providing a
reference against which results of other methods can be compared.
6. Publications. Presentation and Theses:
1. Fox, D.L., J.E. Sickles, M.R. Kuhlman, P.C. Reist and W.E. Wilson.
1975. Design and Operating Parameters for a Large Ambient Aerosol
Chamber. J. Air Poll. Cont. Assoc. 25:1049-1053.
2. Fox, D.L., M.R. Kuhlman and P.C. Reist. 1976. Sulfate Aerosol
Formation Under Conditions of Variable Light Density. Proceedings
of International Conference on Colloids and Interfaces. Academic Press.
In Press.
3. Reist, P.C., W. Marlow and G. Dwiggins. 1976. Aspects of the
Performance of the Electrical Aerosol Analyzer Under Nonideal Conditions.
0. Aerosol Sci. In Press.
4. Wright, R.S. 1976. M.S. Thesis. Feasibility Study for the
Use of a Long-Path Infrared Spectrometer in an Outdoor Chamber.
5. Dwiggins, G.A. 1976. M.S. Thesis. The Effect of Trace Gaseous
Constituents in the Air on Data from the Electrical Aerosol Size Analyzer.
7. Plans:
1. To continue studies in outdoor chamber on sulfate aerosol formation.
2. An exploring wire generator will be used for studies of the effect
of pre-existing nuclei on aerosol growth.
12
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1. Task Title: Formation of Atmospheric Aerosols - Smog Chamber Research.
2. Objective:
To study the formation and growth of aerosols formed from the photo-
oxidation of mixtures of SCL, hydrocarbons, and NO .
£ X
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: W.E. Wilson
5. Progress
Studies by Kittelson and his students have been made of mixtures
of NC + NO + S02 in the University of Minnesota's 18 m3 smog chamber.
Analysis of hydrocarbon + NO + S02 experiments has shown a very
close coupling between aerosol and chemical behavior. Disappearance
of NO and onset of 03 formation are accompanied by a sudden increase in
the rate of aerosol formation and a broadening of the aerosol size dis-
tribution.
3
Measurements have been made by Kwok of wall losses in the 18m smog
chamber. Under typical sampling conditions the bag surface-to-volurae-,
ratio is 2.2 m- , and the first order wall loss constant is 0,19 hr." .
The chamber lights were upgraded to double the current light intensity
Of kdNO£ = °'2 min" '
6. Publications, Presentations, Theses:
1. Kwok, Kui-Chiu. 1975. Coagulation and Wall Losses in a Smog Chamber.
M.S. Thesis. Mechanical Engineering Department, University of Minnesota, MN.
i. Kocmond, W.C., D.B. Kittelson, J.L. Yang and K.L, Demerjian. 1975. Study
of Aerosol Formation in Photochemical Air Pollution. EPA-650/13-75-007.
3. Kocmond, W.C., D.B. Kittelson, J.L. Yang, K.L. Demerjian and K.T, Whitby.
1975. Aerosol Formation in Simple Photochemical Systems. Environ. Sci. and
Tech.
4. Kocmond, W.C., D.B. Kittelson, J.L. Yang and K.L. Demerjian. Determination
of Formation Mechanisms and Composition of Photochemical Aerosols. Calspan
Corp., Buffalo, NY. August 31, 1973.
5. Clark, W.E. and K.T. Whitby. 1975, Measurement of Aerosols by the
Photochemical Oxidation of S02 in Air.
7. Plans: 1. To write papers and reports.
Photochemical Oxidation of S02 in Air. J. Colloid Interface Sci. 51:477-490.
13
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1. Task Title: Smog Chamber Study of Sulfur Dioxide Oxidation and Aerosol
Formation Mechanisms.
2. Objective:
To assess the SOg oxidation rates and mechanisms under varying ambient
environments.
To investigate chemical and aerosol behavior under homogeneous photo-
oxidation conditions.
To study surface and droplet catalytic effects on S02 oxidation as
might be expected under in-cloud transformation and power plant plume
conditons.
3. Institution: Calspan
Investigator: W.C. Kocmond
J.Y. Yang
4. EPA Project Officer: B. Dimetriades
5. Progress:
The Calspan smog chamber facility consists of a cylindrical chamber,
30 feet (9.14 meters) in diameter and 30 feet (9.14 meters) high, enclosing
a volume of 20,800 ft^ (590m3). The inner chamber surface is coated with a
fluoroepoxy-type urethane, which has surface energy and reactivity properties
comparable to those of FEP Teflon. Illumination within the chamber is provided
by 28.6kw of fluorescent blacklight and sunlamps installed inside 24 lighting
modules and arranged in eight vertical channels attached to the wall of the
chamber. Measured light intensity, using the k^ [N02] method reported by
Stedman and Niki (1973), is k^ ^ 0.35 min~^. Varying light intensities can
be provided by selectively turning off some of the light modules and lamps.
Air purification within the chamber is accomplished by recirculating the
air through a series of absolute and activated carbon filters.
To date over 60 experiments have been conducted using systems ranging
from S02 in clean air, to irradiations of auto exhaust + NOX + S02- A
number of preliminary experiments have also been performed using the laboratory
cloud + SOg system. Numerous tests were conducted to examine aerosol collection
methods and sulfate analysis techniques. From an analysis of the smog chamber
aerosol and chemistry data, the following points can be made:
1. The S02 photooxidation rate in hydrocarbon + NOX polluted air
is accelerated over that for the S02 + clean air systems, and generally lies
in the range of 1 to 3% hr-1. Results of sulfate analysis show that the S02
photooxidation rate during the accelerated growth period is about 2.3% hr-1
for the propylene + NOX + S02 system, and approximately 1.5% hr-1 for the
cyclohexene + NOX + S02 system.
2. Total aerosol production is greatly accelerated in the propylene
or cyclohexene + NOX + S02 reaction systems over that observed for the HC
+ NOX system alone. The measured maximum rate of aerosol formation was 20
times greater for the propylene + NOX + S02 test mix compared to the propylene
+ NOX system without S02- Comparison of the aerosol volume production data
in these two systems suggests that organic aerosol formation may be
14
-------
enhanced due to the presence of S02-
3. For the auto exhaust + 862 experiments, the average photooxidation rate
of S02 as determined from chemical analysis was about the same for all experiments,
with or without combustion nuclei. In these experiments, however, a HC/NOX ratio
of about 6:1 was used and NO disappearance did not occur in less than about six
hours. During this lengthy period, any effects of the combustion nuclei on
subsequent aerosol formation presumable would have been obscured. Additional
tests of shorter duration are recommended to permit the determination of RSQ^
after NO oxidation is completed and appreciable ozone has been formed. Ratios
of HC/NOX of about 15:1 will be needed to significantly accelerate the NO
oxidation process.
4. Initial particle concentrations were an order of magnitude higher for
the auto exhaust tests using leaded fuel in comparison to tests with non-leaded
fuel. Once irradiation was started, the maximum particle concentration and rate
of aerosol production were also higher for the leaded fuel cases.
5. The chemical (barium perchlorate titrations) and aerosol (EAA data)
methods for determining R$QO were only comparable during the initial stages of
the auto exhaust experiments. Later, the EAA analysis was higher, suggesting
that the aerosols thus formed were of a mixed nature (i.e. organics, nitrates
and sulfates).
6. The largest amount of light-scattering aerosol was formed in the
leaded fuel auto exhaust experiments.
7. Procedures have been established for producing realistic clouds within
the Calspan smog chamber for studies of in-cloud $02 to sulfate transformation.
8. Efforts directed toward obtaining reliable aerosol samples and
establishing usable analysis procedured for determining sulfate content are
still in progress. Plans for the immediate future call for aerosol sampels to
be analyzed for total sulfur at EPA using X-ray fluorescence and liquid ion
chromatography. A portion of each sample will also be analyzed at Calspan
using the barium perchlorate titration technique.
9. Auto exhaust + S02 and in-cloud S02 to sulfate transformation
studies will be resumed when reliable sampling and analysis procedures are
developed and verified.
6. Publications, Presentations and Theses: None.
7. Plans:
1. To study reaction rates of sulfur dioxide with auto exhaust and water
droplets.
15
-------
1. Task Title: Study of Vapor Pressures of Systems Forming Atmospheric Aerosols
2. Objective:
To measure basic physical properties of certain multicomponent fluid
mixtures along the equilibrium phase separation curves. The systems chosen
are those involved in the formation of secondary atmospheric aerosols, witn
particular emphasis on the sulfuric acid-water mixture.
3. Institution: Clark College, Atlanta, Georgia
Investigator: G. Brown
4. EPA Project Officer: W.E. Wilson
5. Progress: The laboratory for this project has been constructed and is
essentially complete. The apparatus is designed to determine the total
vapor pressure over bulk fluid mixtures by both capacitance manometer
and ion gauge measurements.
The composition of the vapor above the bulk mixtures is determined
with the use of a time-of-flight mass spectrometer. If the initial
chemical composition of the samples is not significantly effected by
chemical reactions, this latter measurement can be converted to equilibrium
partial pressures for the various constituents of the mixtures, thereby
determining the boiling- and dew-point curves for the mixtures. The tempera-
ture of the mixture samples is controlled to within approximately 1° C in
the range from -60° to + io°C.
Data are being taken on the sulfuric acid-water system.
6. Publications, Presentations, Theses: None
7. Plans:
1. To continue data collection and study of the sulfuric acid-water system.
2. When sufficient data on this mixture has been compiled, to perform
similar measurements on mixtures containing HC1 and HN03.
16
-------
1. Task Title: Formation of Atmospheric Aerosols - Size Distribution
Models for Atmospheric Aerosol,
2. Objective:
To develop better multimodal models to describe the thousands of
atmospheric size distributions measured in the atmosphere during the
past few years.
To develop useful categories for concentration, size distributions,
etc.
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: W.E. Wilson
5. Progress:
Evidence from a variety of field studies suggests that atmospheric
aerosols are in general multimodal, with two to three modes being
observable. The mass or volume distribution is usually bimodal with
a minimum observed in the l-to-3-um diameter range. The particles
larger than a few microns originate from natural or man-made mechanical
processes. The mechanically produced particles are hereafter called
"coarse particles." The particles smaller than a few microns arise
predominantly from condensation processes and are called "fine particles."
The predominant man-made source of these fine particles is combustion
or the condensation of chemical or photochemical reaction products on
nuclei from combustion.
The fine particle range may also show two distinct modes. For
example, a trimodal size distribution was measured 30 m from the road-
way during the GM Sulfate Study (Figure 1). A distinct first mode was
indicated because the source (catalyst-equipped cars) emitted most of
the aerosol in the 0.02 ym nuclei mode, and the accumulation mode (middle
mode) was relatively small because the background on this day was
very low.
The first mode, in the vicinity of 0.02 ytn diameter, results pri-
marily from the direct emission of primary particles from combustion.
The second submicron mode, in the 0.15 to 0.8 ym range by volume, is
the result of either the coagulation of primary particles or the con-
densation of reaction products or water on primary particles. The
third mode, or coarse particle mode, consists of mechanically produced
aerosols with the upper size limited by classification due to sedimenta-
tion. There appears to be very little exchange of mass under most
conditions between the fine and coarse particle ranges in the atmosphere.
Most mass is inserted in the distribution either through the
accumulation mode or through the coarse particle mode. Only under
unusual circumstances near large sources of combustion aerosol (such as
a freeway, or in a plume from a stack) is appreciable mass injected
directly into the nuclei mode (Figure 2).
17
-------
Size Distribution Models for Source Related and Urban Atmospheric Aerosols
Atmospheric volume, mass and chemical size distributions can be fitted
by three independent log-normal distributions.
This procedure has been applied to a large number of size distributions
measured with the Minnesota Aerosol Analyzing System (MAAS), After examininq
this data in some detail, the distributions were grouped into six categories
(Table I):
Clean Background
Observed only in large clean air masses
Several hours away from combustion sources
No nuclei mode
VAC < 2Mm3/cm3
Average Background
Mixture of Clean Background, small amounts of aged urban plumes and local
combustion aerosol
Small nuclei mode
VAC a 5um3/Cm3
VCP independent of VAC and dependent on local sources of dust
Background + Aged Urban Plumes
Average Background + a strong plume from a major urban area
Small nuclei mode determined by local combustion sources
VAC similar to that in an average urban area
VCP determined by local sources of dust
Background + Local Sources
Strong local combustion sources increase VAN to the urban concentrations
of = 0,6 without much increase in VAC over background
Distribution is very dependent on nature of sources
Urban Average
Nuclei mode determined by local sources, primarily automobiles
Accumulation mode determined primarily by aged aerosol from the general
area; VAC = 30 on the average
Coarse particle mode determined by local sources
Urban + Sources
Strong local sources of combustion aerosol, (e,g, automobiles) increase both
nuclei and accumulation modes
Coarse particle mode is influenced by the nature of the source: fine particle
and coarse particle sources are usually unrelated
Concentration is widely variable in time
The size distributions for which the parameters are tabulated in Table I
are plotted in Figure 3 and 4, A typical size distribution measured in the
Labadie coal-fired power olant plume, located in St, Louis, is also shown
in Figure 4. Although both background and plume aerosol distributions usually
have small nuclei and coarse particle modes, most of the aerosol mass is in
the accumulation mode.
18
-------
Except for the clean background and Labadie plume distributions, the
volume of aerosol in the coarse particle mode is relatively constant at
about 30 ym3/cm3 (Table I, Figure 3,4). The accumulation mode volume is
more closely related to anthropogenic contributions than is the coarse
particle mode.
The nuclei mode is an indicator of close (less than 1/2 hour transport
time) sources of combustion aerosol except in those cases where photo-
chemically produced nuclei may be observed in relatively clean air (e.g.,
small accumulation mode). Number concentrations of about 105/cm3 of nuclei
of size less than 0.01 ym have been observed in the Labadie plume during
the summer of 1976, which are apparently due to homogeneous reactions in the
plume.
The formation rate of new nuclei in a coal-fired power plant plume is
only about 3.5 nuclei per cm3-sec. These nuclei contained an insignificant
amount of mass compared to the mass that condensed directly on the particles
in the accumulation mode during the aerosol growth in the same plume.
General Mode Characteristics of the Physical Size Distribution
From modal characterization of the variety of aerosol size distributions,
the following general conclusions have been reached:
1. Nuclei mode. For very fresh combustion aerosols from clean combustion
(e.g., along a freeway), the geometric mean diameter by number (DGN) is about
0.01 ym. For more aged aerosols, DGN may approach 0.02 ym. The geometric
standard deviation (SG) is usually between 1.5 and 1.7. Except for well-aged
aerosols (e.g., away from sources on the earth's surface or well above the
earth's surface), the nuclei mode accounts for most of the aerosol number and
hence the Aitken nuclei count.
2. Accumulation mode. Average geometric standard deviation by volume (SGV)
=2.0 and average geometric mean diameter by volume (DGV) = 0.34 ym. Also,
aged aerosols have a somewhat greater SGV than fresh aerosols; the range
being from 1.8 for fresh aerosols to 2.2 for well-aged aerosols. In
well-aged aerosols the nuclei mode disappears into the accumulation mode by
coagulation and then the Aitken nuclei count becomes equal to the number
of particles in the accumulation mode within the experimental error of the
measurements (about + 30%). This situation appears to be the normal condition
at altitudes greater than about 200 m, and at the surface more than 30 km
from sources of combustion aerosol.
3. Coarse particle (CP) mode. The average geometric standard deviation by
volume of the coarse particle mode (SGV) = 2.3, and the average geometric
mean diameter by volume (DGV) = 5 ym. The log-normal distribution parameters
are more variable for the coarse particle mode than for the accumulation and
nuclei modes; values of DGV having been observed between 3.5 and 25 ym. The
mass concentration in the CP mode varies from a few to several hundred yg/m3.
An examination of the relationship between the volume of coarse particles
(VCP) and the geometric mean size of the coarse particle mode (DGVCP) shows
that DGVCP is nearly constant up to VCP = 30 ym3/cm3 and equal to about 5 ym.
Above 5 ym, DGVCP increases linearly with VCP.
19
-------
6. Publications, Presentation. Theses:
1. Whitby, K.T. Modeling of Atmospheric Aerosol Size Distribution.
Report on Grant #R800971, Sampling and Analysis of Atmospheric Aerosols.
Submitted to: Atmos. Aerosol Res. Sec., Div. of Chem. and Phys.,
Air Pollution Control Office, Environmental Protection Agency, May 1975.
2. Whitby, K.T. and B.K. Cantrell. Size Distribution and Concentra-
tion of Atmospheric Aerosols. Presented at: 82nd Annual Meeting of
the AIChE, August 30, 1976.
3. Whitby, K.T. Physical Characterization of Aerosols. Presented
at: 8th Materials Research Symposium, National Bureau of Standards,
September 21, 1976.
7. Plans:
1. To develop modal parameters using the latest data bases: the
1975 EPA trailer data from Glasgow, MO, the 1975 St. Louis urban
plume data, and the 1976 Labadie power plant data.
2. Improved fitting procedures are being developed that can be used
as part of a routine data reduction package.
20
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LECTRICAL AEROSOL ANAUYZER>
DP(/lm)
Figure 1. Trimodal volume distribution measured 30 m from the roadway
during the General Motors Sulfate Study, October, 1975. The
bars are actual data. Solid lines are the fitted log-normal
distributions.
CHEMICAL CONVERSION
OF GASES TO LOU
VOLATILITY VAPORS
*
I
CONDENSATION GROWTH
OF NUCLEI
PARTICLE DIAMETER, MICROMETER
TRANSIENT NUCLEI OR.
AITKEN NUCLEI RANGE
ACCUMULATION
RANGE
-FINE PARTICLES
MECHANICALLY GENERATED
AEROSOL RANGE
COARSE PARTICLES
Figure 2. Schematic of the principal mechanisms of formation and
removal of a trimodal atmospheric aerosols size distribution.
-------
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.BACKGROUND AEROSOLS
Urban Plume Influenced
Background Average
Auto Influenced
Clean Background
Q.
O
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20
10
.003 .01
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Figure 3. Volume size distributions of four background model aerosols.
Note that except for the CLEAN BACKGROUND, the volume in the
coarse particle mode is about the same.
70 —
60 —
50 —
40 —
I 30
as 20
"
10
URBAN AEROSOLS
Urban
Urban Auto
Influenced
Lobadie Power
Plant Plume
Urban
.abadie Plume
Urban - Auto
Influenced
A
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50
Figure 4. Volume size distributions of two model urban aerosol distributions
and a typical size distribution measured in the plume of the Labadie
coal fired power plant on 8-14-1974,. The power plant plume has only
the accumulation mode.
-------
1 • Task Title: Aerosol Dynamics.
2. Objectives:
To study theoretical aspects of aerosol phenomena and develop a compre-
hensive model for the evolution of the size and composition distributions of
the atmospheric aerosol.
3. Institution: University of Texas, Austin, Texas
Investigator: J.R, Brock
4. EPA Project Officer: J.L. Durham
5. Progress:
The various rate processes which alter the composition and concentration
of urban particulate matter may be summarized by the following relationships:
(rate of change in } /rate of change due) (rate of change
Jcomposition of somes = - [to advection J + *to convection and
Ssize fraction of I [^dispersion
Durban aerosol J •
-------
with deposition processes appearing as boundary conditions. Episode conditions
are marked by well defined mixing heights and small, cyclical advective drainage
flows. This permits a volume averaging procedure for eq. (2) in which dis-
persion and dry deposition appear explicitly in a lumped parameter for removal
rate. The small, cyclical drainage flows suggested also the feasibility of a
Lagrangian cell method in the simulation.
The input and transport of aerosol in a single cell was studied as it
traversed the urban and surrounding areas of Denver at the rate of the drainage
flow,. Fig. 1 presents the moments (mass concentration, number concentration,
and scat) of the calculated size distribution of the Denver aerosol for a
two-day wintertime pollution episode as described by the volume average of eq. 2
in which the cell begins its traverse at Denver's southern edge. In the
calculation of bscat, the refractive index of the aerosol at 500 nm is taken
as (1.55-0.221).
A marked diurnal variation can be seen during the first day with a rapid
decrease in the evening hours as the cell moves out of the city by following
the drainage flows down the Platte River valley. Flow reversal the next day
allows transport of the cell (now containing aged aerosol) once again over the
city with resultant build-up of aerosol concentration.
The values of the various moments in Fig. 1 are all within the range of
experimental observations. Thus, these quantities are all based through eq. (2)
on independent estimates of the primary source emission rates. Figure 2
shows the mass density function at 12-hour intervals. Again the bimodal
forms, the quantitative variation of the density function, and the locations
of modes and saddlepoint are in apparent agreement with typical episode measure-
ments for the various times (cell locations) shown. The presentation of the
rate distributions of the various processes in Fig. 3 illustrates the power of
a rigorous numerical model of the atmospheric aerosol. The importance of all
the processes - coagulation, condensation (in this case sulfuric acid resulting
from the ozone-olefin-S02 reaction), deposition, primary source input - may
easily be studied in terms of their rates in the growth equation.
The fine particle mode grows mainly by coagulation and primary source
input and is diminished by deposition (Fig. 3). The coarse particle mode
grows mainly by primary source input with a minor contribution from coagulation
(turbulent, gravitational, and Brownian coagulation are all considered), and
is strongly diminished by deposition. Although this model represents a large
simplification of typical episode conditions, it provides valuable insight into
the aerosol dynamics. It has provided useful predictions about the mechanisms
of particle growth and visibility effects discussed elsewhere.
The volume average of eq. (2) has been used to explain why the mass density
functions of urban aerosols are multimodal. Apart from the explanation based
on two major size classes associated with primary source inputs, we wished to
determine if multi-modality could result from other processes as well (Figs.
4, 5 and 6). Fig. 4 indicates the test mass density function resulting from
elimination of all aerosol processes except input of primary sources which
were purposely chosen to give the uniform mass density functions displayed.
Fig. 5, showing a sharply peaked unimodal function, results from addition of
the processes of coagulation and dry deposition to the primary source input
of Fig. 4. Finally, a marked bimodal from results if condensation with Kelvin
cut off, coagulation, dry deposition and primary source input are all included
in the evolution equation (Figure 6). Primary-source size distributions, modified
25
-------
by coagulation and deposition, undoubtedly are the principal causal agents in
the production of the currently reported multimodal densities (Figure 2).
However, additional hither to unobserved modes may exist for the atmospheric
aerosol owing to secondary aerosol production, particularly in those cases
where condensable substances and aerosol form a "pollution cloud" (Figure 6)
6, Publications, Presentations, Theses:
1, P.B. Middleton and J.R, Brock. 1976, Simulation of Aerosol Kinetics.
J. Colloid and Interface Sci. 59:249.
2. J.R. Brock, 1974. Repartition de la Charge d'Espace aer Voisinage
d'un Faisceau de Particules. C.R. Acad Sc. Paris 287.
3. J.R. Brock and W.H. Marlow, Charged Aerosol Particles and Air Pollution.
1975. Environ. Letters. 10:53-67.
4. W.H. Marlow and J.R. Brock. 1975. Unipolar Charging of Small Aerosol
Particles. J. Colloid and Interface Sci. 50:32-38.
5. P.B. Middleton and J.R. Brock. Studies in Aerosol Dynamics: The Denver
Field Study Symposium. Environ, Monitoring Series. EPA,
6. Middleton, P.B. and J.R. Brock. 1976. On the Multimodality of Density
Functions of Pollutant Aerosols. Atmos, Environ. 10.
7. P.B. Middleton and J.R. Brock. Dynamic Model for Urban Particulate
Pollution. Submitted to: Atmos. Environ.
8. Brock, J.R. and R. Drake. Coagulation of Aerosols. Symposium on Aerosol
A Science and Technology. Natl. A.I.Ch.E. Meeting, Atlantic City, NJ,
August, 1976.
7. Plans:
1. Complete the computer program to permit atmospheric aerosol
simulation for very general meteorological conditions directly according
to eq. (2). The first application of this program will be the simulation
of the aerosol growth processes for the city of Phoenix to permit testing
of various control strategies.
2. To permit the solution of eq. (1) for the composition distribution
of the atmospheric aerosol. This will permit us to simulate the chemical
transformations which occur in the atmospheric aerosol.
26
-------
24 36
HOURS
NUMBER, CC~' X 10* o
MASS, GRAMS X 10"" +
BSCAT, I/CM X IO'7 *
Figure 1. Moments of calculated
size distribution of
Denver aerosol for a two
day wintertime pollution
episode in Lagrangian cell
traversing city with
cyclical drainage flows.
Figure 2. Mass density function of
Denver aerosol for two day
wintertime pollution episode
in Lagrangian cell travers-
ing city with cyclical
drainage flows.
HOO
10°
DIAMETER, U,M
TIME 1200 HOURS
DISTRIBUTION, P_C/CC
TOTAL RATE ,
COAGULATION
DEPOSITION ,
SOURCES,
PG/CC-ScC X 10 '
PS/CC-SEC X I0"!
*•
PG*:C-SEC x io"= x
PGAX-SEC X I0~9 X
/-,-s
Figure 3. Rate distributions of
various processes shaping
size distribution during
two day wintertime pollution
episode for city of Denser.
CONDENSATION, °G/CC-SEC X 10
-8
27
-------
1. Task Title: Biogenic Emission of Aerosol Precursors
2. Objective:
To determine the contribution of naturally occuring bacterial sources
to the total atmospheric sulfur load. Select monitoring sites showing
good promise of biogenic sulfur production with a "clean" reference site
nearby.
To monitor atmospheric sulfur levels at selected sites along with
meteorological data. (Wind speed, wind direction and temperature).
To correlate sulfur levels with natural cycles (tides, day/night
and seasonal).
3. Institution: EPA-ERC, ESRL-ARB
Investigators: L.L. Spiller; N. Schmidt, Gilles Kay, G. DeJong,
R. Reardon, G. Namie. (student aids)
4. EPA Project Officer: W.E. Wilson
5. Progress:
(a) A method of collection of volatile sulfur compounds using
selective filters treated with various silver salts and (OH-) anions
was tested for temperature and humidity effects on collection efficiency.
AgNOs treated filters were selected for H2S absorbtion and Li OH treated
filters for S02 absorbtion. X-ray fluorescence is used for analysis.
(b) Further laboratory testing will be done on these filters to determine
performance limits regarding air temperature,, humidity, flow rate,
selectivity, and sulfur load extremes and to compare XRF non-destructive
analysis with other destructive wet methods of higher accuracy but greater
costs. (D.F. Natusch Method), (c) Design instruments and interface
circuitry to support environmental studies anticipated in the near future.
Future tests will be made at selected sites using a higher flow rate for
shorter sampling time or, a much more accurate analytical method must be
used. Currently we are using XRF with measurements at .06 um/cm2 or ,46 ppb.
6. Publications, Presentations, Thesis:
Presented before the Division of Environmental Chemistry, American
Chemical Society. New Orleans, LA, March 20-25, 1977. Biogenic
Sulfides in the Atmosphere Over a North Carolina Tidal Marsh.
7. Plans:
To develop specially treated filters to selectively absorb different
volatile sulfur compounds.
To collect laboratory data on: collection efficiency, effects of
temperature, humidity, various volatile sulfur selectivities, and ease
and accuracy of analysis at low levels.
To develop a field collection system with high portability.
28
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1. Task Title: Metal Sulfite Complexes
2. Objective:
To determine the existence and kinetices of metal sulfite complex
formation.
To devise methods for the determination of these complexes if
they are found to exist.
3. Investigator: D. Lawinq (Student Aide)
4. EPA Project Officer: J.L. Durham
5. Progress:
Initially, the metal salt studied was FeCl- in solution with
Na2$0 The resulting solution was analyzed spectrophotometrically
over a wavelength range of 600-400 nanometers. The complex, if
formed, could not be isolated from the ionized species with this
method.
The next metal used was Copper in the form of CuCl2» Cuprous
Chloride. Literature research indicated that such a suffite complex
would break down due to hydrolysis in neutral solutions. To
present this from happening, HC1 was added to the solutions at
a molar concentration equal to the SO- concentration.
The absorption spectra still revealed no well-defined peaks
from 800 to 200 nanometers. Oxidation of the Copper ion was one
possible explanation of the transience of any complex formed.
6. Publications, Presentation, Theses: None
7. Plans:
To undertake similar experiments with vanadium salts.
29
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A. ATMOSPHERIC PROCESSES AND EFFECTS
2. Aerosol Characterization and Sources. The utilization of physical
properties, elemental and chemical analyses, and microscopy for the charac-
terization of atmospheric aerosols and the use of this information to
determine the primary and secondary source contributions to urban pollution..
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712.
30
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1. Task Title: Sources and Trace Metals in Urban Aerosols
2. Sub-Task Title: Urban, Non-urban, and Marine Aerosol Studies.
3. Objectives:
Apply developed sample collection and PIXE analysis techniques
to studies on urban, non-urban, and marine aerosols.
4. Institution: Department of Oceanography, Florida State University
Tallahassee, Florida 32306
Investigator: John W. Winchester
5. EPA Project Officer: Ronald K. Patterson
6. Progress:
Under this sub-task title eight major studies were performed.
Each study used the Florida State University Tandem Van de Graaff
Accelerator and Proton Induced X-Ray Emission to analyze for trace
elements in collected aerosols.
Study 1. Size fractionated aerosols,
in St. Louis during August,
were collected
study show that:
using the Battelle
1973. The results
impactor,
of this
1. Particle size distributions of S, Cl, K. Ca, Ti, V, Mn, Fe,
Cu, Zn, Br, and Pb can be measured in samples from 0.7 m^ of air
collected over 12-hour intervals at 1 liter/min flow rate, with
precision of single analyses generally 10-30%, except near the
nanogram detection limit.
2. Some elements, e.g. Ca, Fe, Ti, K, show a tendency for
highest concentrations in air measured in largest particle size
fractions, and the pattern of distribution of concentration with
size is relatively invariant. Predominantly dispersion source
processes may account for their entry into the atmosphere.
3. Other elements, e.g. S, Pb, Zn, have substantial proportions
of their atmospheric concentrations on smallest particles and
show greater variability in particle size distribution patterns,
suggesting aerosol formation processes of vapor condensation at
high or low temperatures.
4. During 16-22 August 1973 an atmospheric change occurred
from a period of low speed and mostly southerly air flow, with
evident haze and air pollution, to higher speed and westerly
shifting to easterly air flow, with improved visibility and air
quality. The change was associated with drops in concentrations
of Ti, Fe, Ca, K, and S but not Zn or Pb at the south site.and
Ti but not the other elements at the central site. Transport of
air pollution from industrial sources south of the city is indicated.
5. The central site showed diurnal variations during the first
period where concentrations of Ti, Fe, Ca, K, and S were higher
in samples taken from midnight to noon than in those from noon to
midnight. Variations were greatest for intermediate sized particles.
31
-------
Study 2. Time sequence samples, using the Jensen-Nelson "Streaker,"
were collected simultaneoulsy at 25 sites in St. Louis during August,
1975. From this study, correlations of elemental concentrations in
the air with time (2 hr. resolution) and location, plus inter-element
time correlations at a single site, inferences can be made about the
transport of elemental constituents from pollution and natural sources,
as well as gas-to-particle transformations of certain elements, such
as sulfur.
Study 3. Fractionated aerosols were collected in north Florida
by using a Battelle impactor. Size-specific aerosol removal processes
can be evaluated by sampling urban, forest, and coastal locations, and
by choosing approximately 48-hour sample-averaging intervals.
It was found that elements contained in the largest particles, especially
those of >4ym, display the greatest degree of average concentration
difference between sites, a result suggesting short atmospheric residence
times and the importance of local dispersion sources and atmospheric
cleansing processes in regulating the particle concentrations in air.
Elements contained in particles of <2ym diameter showed little average
concentration difference between sites unless they were regulated by
large-scale sources and transport processes. Sulfur in the smallest
particles showed a marked constancy of concentration, but it may be
modified in the largest particle size ranges in relation to proximity
to the seacoast. No evidence was found for dependence of particulate
sulfur concentrations on local pollution sources.
Study 4. Size fractionated aerosols were collected in Miami,
Florida. Miami provided an opportunity to observe elemental con-
stituents of the aerosol as it may be modified from the predominately
marine atmosphere background by urban nonindustrial activity.
Major sources of the elements are the tropospheric land-derived particles
and added sea spray particles carried by prevailing southeasterly
winds, soil dust constituents raised by human activity in the city,
automotive emissions that contain lead and halogen elements, and
emissions from stationary combustion sources that include oil- and
gas-fired power plants and refuse incinerators.
This study was undertaken to evaluate the relative importance of these
major sources for 14 elemental constituents.
Study 5. A data set from Bermuda, consisting of ten size frac-
tioned distribution measurements of marine aerosol, was used in a 2-
component model to resolve tropospheric from sea surface derived trace
elements.
Study 6. Samples were collected in Bolivia, central Brazil, and
Argentina, using Battelle cascade impactors, Jensen-Nelson "Streakers"
and total particulate filters. These samples were collected for
comparisons with data from the North American continent and for use in
transport models.
32
-------
Study 7. As an example of the application of the PIXE analysis
technique to the study of sulfur and related trace elements from
non-urban locations, comparisons were made between results from a
remote continental station in the Southern Hemisphere, Chacaltaya
Mountain, near LaPaz, Bolivia, and a mid-ocean station in the Atlantic
of the Northern Hemisphere, at Bermuda. Size fractionated samples
were collected at both sites.
Study 8. Biased data set averaging has been used to examine
aerosol elemental composition data for air mass directional effects.
Samples collected in north Florida during spring and summer 1973
were influenced by local and remote continental sources and additionally
by maritime sources when air flow was southerly. Judgements of air
movements during the collection of 32 5-stage cascade impactor samples
were made by examination of daily surface weather maps, 3-hourly
surface winds in Tallahassee, and semi-diurnal balloon soundings to
1524 meters. Averages of elemental abundances as a function of
particle size, determined by proton-induced X-ray emission, PIXE, were
computed for a 14-sample set biased toward marine air flow conditions
and for a 6-sample set biased toward continental air flow, excluding
12 additional samples where air flow characteristics were variable or
periods of very low wind speed were experienced. By regarding Fe to be
of continental origin in all samples, qualitative indications of
provenance were observed.
7. Publications:
1. J.W. Winchester, D.L. Meinert, J.W. Nelson, T.B. Johansson, R.E.
Van Grieken, C.Q. Orsini, H.C. Kaufmann and K.R. Akselsson. In:
Proc. 2nd Intl. Conf. Nucl. Methods in Environmental Res.,
Columbia, MO, July, 1974, USERDA Conf-740701, pp. 385-394.
2. J.O. Pilotte, J.W. Nelson and J.W. Winchester. Application of
multi-station Time Sequence Aerosol Sampling and Proton Induced
X-Ray Emission Analysis Techniques to the St. Louis Regional Air
Pollution Study for Investigating Sulfur-Trace Metal Relationships.
In: Proc. ERDA X and Gamma Ray Symposium, Ann Arbor, MI, May
19-21, 1976 (Conf. 760539).
3. T.B. Johansson, R.E. Van Grieken and J.W. Winchester. Elemental
Abundance Variation with Particle Size in North Florida Aerosols.
Journal of Geophysical Research. 1976. 81:1039-1046.
4. K.A. Hardy, K.R. Akselsson, J.W. Nelson and J.W. Winchester.
Elemental Constituents of Miami Aerosol as a Function of Particle
Size. Environmental Science and Technology. 1976. 10:176.
5. D.L. Meinert and J.W. Winchester. Chemical Relationships in the
North Atlantic Marine Aerosol. Journal of Geophysical Research.
(In Press)
33
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6. L.C.S. Boueres, F. Adams, J.W. Winchester, C.Q. Orsini, J.W.
Nelson, T.A. Cahill and D.R. Lawson. Sulfur and Heavy Metals
in South American Urban and Non-urban Atmospheres. In: Proc. of
the World Meteorological Organization Technical Conference on
Atmospheric Pollution Measurement Techniques, Gothenburg, Sweden,
October 11-15, 1976. Conf. Proc. (In Press)
7. J.W. Winchester. Sulfur and Trace Metal Relationships in Non-urban
and Marine Aerosols Studies Using Proton Induced X-Ray Emission.
Nuclear Instruments and Methods. (In Press)
8. T.B. Johansson, R.E. Van Grieken and J.W. Winchester. Marine
Influence on Aerosol Composition in the Coastal Zone. Journal
de Recherches Atmospheriques. 1974, pp. 762-776.
8. Plans:
This grant is completed. A final report is forthcoming.
34
-------
100
50 .
5 so
Q.
•to
16'
JO1
10
Figure 4. Mass density resulting
from only input of pri-
mary sources. Primary
sources input rates
chosen to yield a
rectangular density.
100% units = lOOpg/cc
100
!0
Figure 5. Unimodal mass density
resulting from input
of primary sources of
Fig. 4 coagulation,
and deposition.
100
0' -I- II I I Illl 1 1 I I I lilt I I I I I i ill I 1 I I I nil
Figure 6. A bimodal mass density
resulting from input
of primary source of
Fig. 4 plus coagulation,
deposition, and conden-
sation, including the
Kelvin term for varia-
tion of vapor pressure
with curvature.
OIRHETEB. [jn
-------
1. Task Title: Relationship of the Smog Aerosol to Pollution Sources
2. Objective;
To develop experimental and theoretical methods for relating the
properties of the pollution aerosol to the characteristics of emission
sources.
3- Institution: California Institute of Technology, Pasadena
Investigator: S.K. Fried!ander
4. EPA Project Officer: VI.E. Wilson
5. Progress:
Homogeneous nucleation in ambient urban air was documented by
watching time profiles of condensation nuclei and carbon monoxide before
and after changes from daylight savings time to standard time. An increase
in condensation nuclei occurred soon after sunrise both before and after
the time change, while the CO increase tended to be shifted an hour along with
anthropogenic activity; therefore, some homogeneous nucleation occurs soon
after sunrise.
Quantitative experiments were conducted using a 60 m3 Teflon reac-
tor. The bag was filled with ambient air of varied aerosol loadings. The
air in the bag was doped with S02, NOX, and propylene to facilitate formation
of sulfate aerosol by homogeneous gas phase reactions. Reaction rates varied
from 0.288 ppb S02/hour to 144.0 ppb SO^/hour by varying the concentrations
of reactants from near ambient levels to levels higher than ambient. Experi-
mental results indicate that homogeneous nucleation becomes more important
as rates of aerosol production increase and initial aerosol loadings decrease.
A theoretical model has been developed which predicts the relative
amounts of aerosol accumulating on new and original particles as functions
of time, aerosol formation rate and amount of pre-existing aerosol. The
evolution of the size distribution of the initial aerosol as a result of
condensational growth can also be calculated: agreement with experimentation
is very good.
The distribution of aerosol nitrate compounds with respect to par-
ticle size is also under study. A new technique has been developed for the
measurement of aerosol nitrate deposited on the stages of an impactor. The
method has been applied to the aerosol collected with the low pressure
impactor at various locations in and around Los Angeles. Preliminary
results indicate a bimodal distribution of nitrate with respect to particle
size.
6. Pub 1 i ca t_1_ons_, P res en ta ti ons. Th es es:
1. Heisler, S.L. and S.K. Friedlander, Growth Mechanisms for Urban Aerosol
Particles. In: Proceedings of the International Colloquium on Drops and
Bubbles, California Institute of Technology-JPL. August 1974, Vol. II, p.553.
2. Grosjean, D. and S.K. Friedlander. Gas-to-Particle Distribution Factors
for Organic and Other Pollutants in Los Angeles. J. Air Poll. Control Assoc.
36
-------
3. Grosjean, D. 1975. Solvent Extraction and Organic Carbon Determination
in Atmospheric Particulate Matter: The Organic Extraction-Organic Carbon
Analyzer (OE-OCA) Technique. Anal. Chem. 47(6):797-805.
4. Roberts, P.T. and S.L. Friedlander. 1976. Analysis of Sulfur in
Deposited Aerosol Particles by Vaporization and Flame Photometric Detection.
Atmos. Environ, 10:403.
5. Roberts, P.T. and S.K. Friedlander. 1976. Photochemical Aerosol
Formation S09, 1-Heptene, and NO in Ambient Air Environ. Sci. and Technol.
10:573. * x
6. Heisler, S.L. and S.K. Friedlander 1976. Gas-to-Particle Conversion
in Photochemical Smog: Growth Laws and Mechanisms for Organics Atmos.
Environ. 10:215.
7. Friedlander, S.K. Gas-to-Particle Conversion: A Key Problem in Air
Pollution. Presented at: The Research Directors' Conference, California
Institute of Technology-Industrial Associates, Pasadena, CA April 19, 1976.
8. Friedlander, S.K. Gas-to-Particle Conversion. Presented at: The
Department of Meteorology Seminar Series, University of California, Los
Angeles, CA April 21, 1976.
9. Flagan, R.C. and S.K. Friedlander Particulate Formation in Pulverized
Coal Combustion - A Review Presented at: The AIChE National Meeting, Atlantic
City, NJ August 31, 1976.
10. Friedlander, S.K. Fundamentals of Gas-to-Particle Conversion - A
Review. Presented at: The AIChE National Meeting, Atlantic City, NJ
August 31, 1976.
11. Roberts, P.T., Gas-to-Particle Conversion: Sulfur Dioxide in a Photo-
chemical ly Reactive System Ph.D. Thesis California Institute of Technology,
Pasadena, CA May 1975.
12. Heisler, S.L. Gas-to-Particle Conversion in Photochemical Smog: Growth
Laws and Mechanisms for Organics Ph.D. Thesis California Institute of
Technology, Pasadena, CA July 1975.
7. Plans:
1. To analyze data and conduct additional experiments involving simultaneous
formation of organic and sulfate aerosols. Previous work on this grant
indicates that condensable organic products tend to accumulate in larger
size ranges than sulfates because of the Kelvin effect. By using a low
pressure impactor it will be determined whether simultaneous condensation
of organics and sulfates results in a larger average size for sulfate con-
taining aerosols than condensation of sulfates alone.
2. Experiments to determine the effect of different types of sources
including the marine aerosol, NO pollution and agricultural fertilizers on
particle size distribution will Be continued.
3. Low pressure impactor data collected durinp the Santa Monica Freeway
Sulfuric Acid Aerosol Project will be analyzed. The freeway and background
data will be compared to permit estimation of the sulfur distribution with
respect to particle size in primary automobile emissions.
37
-------
1- Task Title: A Study of the Identity and Sources of Atmospheric Aerosols.
2. Objective:
To develop and apply optical and electron microscopy procedures
for the identification and characterization of atmospheric aerosols.
3. Institution: I IT Research Institute, Chicago, Illinois
Investigator: R.6. Draftz
4. EPA Project Officer: J.L. Durham
5. Progress:
1. In November 1975, I IT Research Institute and the EPA conducted an
airborne dust sampling study in Maricopa County, AZ, to characterize the
types and sources of suspended dust impacting on the city of Phoenix.
The purpose of this study was to discover whether high suspended dust
concentrations in the city are due to particles transported from
surrounding deserts or from local sources.
Suspended dust samples were collected with a network of hi-volume
filters and impactors located in and outside of Phoenix. These fixed
monitoring sites were supplemented with dust samples collected with an
EPA helicopter at heights from 30 to 500 meters.
Dust concentrations measured with hi-volume filters averaged
200 pg/m3 for samples located 3 to 20 meters above ground level and
130 ug/m3 for samples measured 30 to 500 meters above ground. Therefore,
dust concentrations decreased with height.
The dust particles were identified by optical and electron micro-
scopy. The majority of particles contributing to high dust concentrations
were minerals -- feldspars, quartz, calcite, mica, and clays. Carbon-
aceous particles from auto exhaust and rubber tire particles were also
present as minor components in every sample, even those collected in
sparsely populated rural areas.
The size, composition, and concentrations of these particles, com-
bined with meteorological data, indicate that the particle sources were
predominately local to the sampling sites. Vehicular traffic and
farming are judged to be the primary contributors to the high dust
concentrations in Phoenix. Particles from industrial sources were
insignificant.
2. Aerosols were collected in powerplant and urban plumes emanating
from St. Louis, MO, during July and August, 1975. The samples were
collected at various distances and altitudes with an instrumented
aircraft. Polarized light and electron microscopy were used to identify
the types of aerosols formed and transported in the plume.
Sulfuric acid or ammonium sulfate was the major, respirable com-
ponent found in every sample. Minerals, flyash and a very unusual
carbonaceous aerosol were minor components of each sample. These samples
38
-------
provided the first direct evidence of sulfuric acid in urban and power-
plants and also provided proof that they are transported at distances
of up to 200 miles.
6. Publications, Presentations, Theses:
1. Microscopical Analysis of Aerosols Transported from St. Louis.
Presented at: American Chemical Society Meeting, New York City, NY,
April, 1976.
2. Aircraft Collection and Microscopical Analysis of Ambient Aerosols
from Urban Atmospheres. Air Pollution Control Association Meeting,
Portland, OR, June, 1976.
3. Comparison of Elemental and Microscopical Analyses of Atmospheric
Aerosols. American Chemical Society Meeting, New York City, NY,
April, 1976.
4. Similarities of Atmospheric Aerosols from Four Major U.S. Cities.
Eighth Aerosol Technology Meeting, Research Triangle Park, NC, October,
1975.
5. Morphology of Airborne Dust in Maricopa County, Arizona. In
preparation for presentation at: the 1977 AAAS Symposium on Denver
Dust, Denver, CO, February, 1977.
7. Plans:
1. A new filter/impactor substrate has been discovered which may permit
non-destructive analysis of atmospheric aerosols by microscopy, X-ray
spectroscopy and chemical analysis. The present substrates are not com-
patible for all analyses, therefore increasing the number of samples that
must be collected to obtain a reliable and complete characterization of
aerosols. Laboratory tests and limited field trials will be performed
to evaluate the suitability of this substrate for multiple non-destructive
analyses.
2. Microscopical image analysis will be developed to permit quantita-
tive measurement of aerosol size and concentration for total samples, as
well as for individual particle types within a sample. Polarized light,
UV fluorescence, dispersion and chemical staining by optical microscopy
will be explored as methods to enhance aerosol discrimination and detection.
Backscattered electron and micro X-ray emission imaging will be applied
to submicron aerosols as a means of performing particle size by aerosol
type.
39
-------
1. Task Title: Analysis of Air Pollutants by Mass Spectroscopy.
2. Objective:
To examine the usefulness of high-resolution mass spectroscopy without
prior chemical separations in determining the composition of the organic
portion of the atmospheric aerosol.
To investigate the composition of real aerosol samples at various urban
sites.
3. Institution: University of Washington, Seattle, Washington
Investigator: A.L. Crittenden
4. EPA Project Officer: R. Patterson
5. Progress:
High-resolution mass spectroscopy was shown to be a useful means of
characterizing the organic fraction of the urban aerosol. Quantitative
accuracy was limited, particularly for compounds of low abundance. Some
ambiguities were found in the assignment of origins of ions formed in the
mass spectrometer.
Major constituents of fine particles in urban atmospheres are sulfuric
acid or sulfates, and hydrocarbons. Other compounds that can be detected
include phenols, aromatic carboxylic acids (and possibly esters) and aliphatic
dibasic acids. Evidence was found of several other difunctional compounds,
including nitrate or nitrite species.
Strong evidence was found for the presence in some urban aerosols of
compounds reported by others as products of the oxidation of toluene in
smog chamber reactions. Less evidence was found for products of the
oxidation of terpenes.
A few samples of automobile exhaust particulates have been analyzed.
The occurrence of benzoic acid and the benzol ion in mass spectra appear to
be possible indicators of automotive contribution to the organic components.
Results for a large number of compounds are provided for 88 aerosol
samples collected at sites located in the greater Los Angeles, Seattle,
St. Louis and Denver Areas.
6. Publications, Presentations, Theses:
1. Crittenden, A.L. Analyses of Air Pollutants by Mass Spectroscopy.
EPA-600/3-76-093, U.S. Environmental Protection Agency, Research Triangle
Park, NC, 1976. 287pp.
2. Schuetzle, D., A.L. Crittenden and R.J. Charlson. 1973. Application
of Computer Controlled High Resolution Mass Spectrometry to the Analysis
of Air Pollutants. J. Air Poll. Control Assoc. 23:704.
3. Schuetzle, D., D.R. Cronn, A.L. Crittenden and R.J. Charlson. 1975.
Molecular Composition of Secondary Aerosol and Its Possible Origin. Environ.
Sci. Technol. 9:838.
40
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4. Knights, R.L., D.R. Cronn and A.L. Crittenden; Diurnal Patterns of
Several Components of Urban Participate Air Pollution. Presented at:
The Pittsburgh Conf. on Analytical Chemistry and Applied Spectroscopy,
Cleveland, OH, March 1975,
5. Cronn, D.R. 1975. Analysis of Atmospheric Aerosols by High-Resolu-
tion Mass Spectrometry. Thesis to be submitted to: University of Washington, WA.
7. Plans:
Project terminated and reported in:
Crittenden, A.L. Analysis of Air Pollutants by Mass Spectroscopy. EPA-
600/3-76-093, U.S. Environmental Protection Agency, Research Triangle
Park, NC, 1976. 287pp.
41
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1. Task Title: Chemical Characterization of Model Aerosols
2. Objective:
To identify the molecular structure of components of aerosols formed
from individual hydrocarbons under simulated atmospheric conditions,
To relate aerosol constituents to the type of aerosol precursor and
chemical reaction.
3. Institution: Battelle-Columbus Laboratories, Columbus, Ohio
Investigators: David Mendenhall, P.M. Jones, C.J. Riggle, A.D. Graffeo,
D.F. Miller, W.E. Schwartz
4. EPA Project Officer: R.K. Patterson
5. Progress:
Model aerosols were generated by irradiating individual hydrocarbons,
toluene and 1-heptene in air in the presence of NOX or NOX/S02- The collected
aerosols were subjected to analysis by mass spectrometry and chromatographic
techniques, both with and without chemical derivatization. The organics
associated with the vapor phase were collected with a chromatographic adsorbant
trap and analyzed by gas chromatography with mass spectrometric detection.
The organic species associated with 1-heptene aerosol reaction products
were tentatively identified as n-hexaldehyde, cyclohexanol (or an n-hexenol),
and'1-heptene epoxide. The aerosol from 1-heptene revealed over 130 peaks
on direct mass spectral analysis in a heated probe (Figure 1). The high
molecular weight products are evidently formed by condensation of fragments
from individual 1-heptene molecules.
The gas-phase species from toluene include compounds tentatively iden-
tified as simple transformation products of the hydrocarbon (Figure 2).
Analysis of the aerosol from toluene, after derivatization with a trimethyl-
silylating reagent, revealed a number of more highly oxidized products whose
structures were inferred from m/e values of their parent ions (Figure 3).
The products observed had undergone little or no oxidative degradation,,
and a considerable degree of ring substitution had taken place. Minor
differences were observed between toluene/NOx and toluene/NOx/S02. No
organic sulfur-containing compounds were detected. All major products were
common to both experiments. Of the nine major products - Benzaldehyde,
Nitrophenol, Nitrotoluene (3 isomersLand Nitrocresols (4 isomers); eight
contain a nitro group.
In the toluene/NOx/S02 system, an additional major product formed which
appears to be a polar compound of molecular weight 122. This compound doesn't
contain sulfur, and its mass spectrum is consistent with that of methyl-p-
benzoquinone, but has not been verified with a standard.
The Ames test for mutagencity was carried out with unfractionated
aerosols from both 1-heptene and toluene. No carcinogenic properties were
revealed in any of the aerosol samples tested.
42
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6. Publications, Presentations, Theses:
1. G.D. Mendenhall, P.M. Jones, A.P. Graffeo, W.E. Schwartz and W.E. Wilson.
The Composition of Certain Atmospheric Aerosols, In: 171st American Chemical
Society Meeting, New York, NY, April 1976.
2. W.E. Schwartz, P.W. Jones, D.F. Miller and G.D. Mendenhall. Organic
Composition of Model Aerosols. California Air Environment. In Press.
7. Plans:
The project has been terminated and reported in:
Schwartz, W.E. Chemical Characterization of Model Aerosols. EPA-650/3-74-011
U.S. Environmental Protection Agency, Research Triangle Park, North Carolina.
1974. 130pp.
Schwartz, W.E., G.D. Mendenhall, P.W. Jones, C.J. Riggle, A.P. Graffeo and
D.F. Miller. Chemical Characterization of Model Aerosols. EPA-600/3-76-
085, U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina. 1976. 80pp.
43
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"11' i' i'
60 80 100 20 40 60 80 200 20 40 60 80 300 20 40 60 80 400 20 40 60 80 500 20 40 60 80 600
M/E
FIGURE 1. CHEMICAL IONIZATION MASS SPECTRUM OF 1-HEPTENE AEROSOL
(SAMPLE M599). SUCCESSIVE SPECTRA RECORDED AS PROBE
TEMPERATURE RAISED FROM 25 TO 200 C
100-
90-
80-
TO-
30-
20-
10-
0
TOLUENE/NO,,
VAPORS
10 20 30 40 50
Spectrum Number
60 70 80 90 100 110 \2Q 130 140 150 160 170 180 190 300 210 220 230 240 250 260 270
FIGURE 2. METHANE IONIZATION GC-MS ANALYSIS OF VAPOR PHASE
ORGANIC COMPOUNDS ASSOCIATED WITH TOLUENE/NOx
AEROSOL
44
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45
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1. Task Title: Sources and Trace Metals in Urban Aerosols.
2. Sub-Task Title: Aerosol Properties Relavent to Health Effects.
3. Objectives:
Design experiments which apply sensitive X-Ray analysis techniques to
the measurement of aerosols related to human respiratory uptake and deposition,
4. Institution: Department of Oceanography, Florida State University
Investigator: John W. Winchester
5. EPA Project Officer: Ronald K. Patterson
6. Progress:
The particle size distribution of lead, bromine, chlorine and calcium
in exhaled aerosols from a human subject breathing normally polluted air
was measured using proton induced X-Ray emission (PIXE) analysis. This
experiment in the respiratory deposition of aerosols utilized two similar
air sampling devices, one for sampling the ambient air directly and one
into which the subject supplied all the air from his exhaled breath.
Both devices were operated by a vacuum pump which drew air at a constant
rate by means of critical flow orifices. The sampling devices used 5
and 6 stage Battelle-type cascade impactors, which operated at flow rates
of 12 liters per minute and 1 liter per minute, and gave resolution down
to 0.5 and 0.25 -pm diameter, respectively, on the impaction stages. Two
aerosol sources were employed: chalk dust generated by blackboard erasers
and lead halide aerosols generated by an automobile operating at idling
speed in a semienclosed space near the subject. Three experiments were
conducted using the two sources separately and combined. Using PIXE analysis
Ca, Pb, Br, and Cl were easily measured in samples collected over a ten-
minute interval.
Figure 1 is a plot of the apparent respiratory deposition fraction for
calcium, lead, bromine and chlorine. A similar pattern is shown for all
elements, with a minimum deposition well under 50% in the region of 0.5um
diameter (aerodynamic equivalent for unit density spheres) and deposition
well over 50% for both smaller and larger particles. In this study fea-
sibility was demonstrated for direct determinations of trace element
respiratory depositions in human subjects breathing aerosols at ambient
air concentrations.
Another study under this sub-task title utilized the data from the
above study and a Los Angeles freeway study to calculate the fraction of
atmospheric lead expected to be deposited in the respiratory tract as
a function of particle size for the upwind and downwind freeway sites.
The calculation indicates the qualitative finding that differences in
a particle size distribution combined with differences in the efficiency
of respiratory deposition may determine the overall magnitude of lead
deposition by aerosol inhalation. Emperical deposition curves for
pulmonary, tracheobronchial, and nasopharyngial regions published by
the Task Group on Lung Dynamics, were used to estimate the extent and
location of lead aerosol deposition, based on the measured Los Angeles
size distributions (Figure 2). For individual upwind and downwind sites,
respectively, total lead deposition summed over all particle sizes are
46
-------
33% and 35% for pulmonary, 5,4% and 5.7% for tracheobronchial , and 9.3% and
7.5% for nasopharyngeal regions; these values do not indicate significant
differences in total deposition of lead with aerosol age. However, within
particle size classes the differences were significant, and these were
expected to be linked with the points of deposition within the lung.
7. Publications:
1. G.G. Desaedeleer, J.W. Winchester, and K.R. Akselsson. Monitoring
Aerosol Elemental Composition in Particle Size Fractions for Predicting
Human Respiratory Uptake. Nuclear Instruments and Methods (In Press).
2. G.G. Desaedeleer and J.W. Winchester. Trace Metal Analysis of
Atmospheric Aerosol Particle Size Fractions in Exhaled Human Breath,
Environmental Science and Technology, Vol. 9, October, 1975, pp.971-972.
8. Plans:
This grant is complete. A final report is forthcoming.
47
-------
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49
-------
1. Task Title: Aerosol Sources Program
2. Objective: To collect ambient aerosols with the goal of identifying
aerosol sources through wind-directional sampling and
sensitive analysis techniques.
3. Institution: EPA, Aerosol Research Branch
4. EPA Project Officer: Ronald K. Patterson
5. Progress: Samples were collected in Miami, St. Louis,and Pittsburgh
between May and July, 1975. Modified Battelle type samplers were
operated by an Aerosol Research Branch designed wind-directional
programmer which operates up to four (4) selectable wind sectors
with two degree resolution. Florida State University Streaker
samplers were also used and both types of samples were analyzed
by Proton-induced X-Ray Emission at Florida State.
A report on the Miami and St. Louis analysis results was
prepared for OAQPS (Tom Pace) in October, 1975. The final draft
report on the data analysis and interpretation of the Miami results
is being prepared under EPA Contract #68-02-2406 by Dr. Kenneth A.
Hardy, Florida International University. St. Louis and Pittsburgh
data reduction and interpretation will begin next month under the
same contract.
6. Publications, Presentations, and Theses: None
7. Plans: Prepare reports on St. Louis and Pittsburgh results by July, 1977,
50
-------
1- Task^ Title: Aerosol Microscopy
2. Objective:
To carry out research studies of the structure, composition and
sources of pollutant aerosol particles and other environmental studies
that may be assigned through the use of electron-optical and optical
X-ray analytical methods.
3. Institution: Environmental Protection Agency, ESRL, ARB, Research
Triangle Park, North Carolina.
Investigator: J. Gerhard
4. EPA Project Officer: J. Gerhard
5. Progress:
The following more recent tasks are completed: Tampa Aerosol Study;
Texas Dust Storm Study; Iron Foundry, Utah Study; Cal-Nevada Study;
Asbestos in Building Materials and Respiraton Filter Deposit examinations.
6, Publications, Presentations, Thesis: None
7. Plans:
Written reports of the analytical results of all future studies
will be distributed to all interested personnel as expediently as possible,
51
-------
4.
5.
Task Title; Field Expedition to Phoenix, Arizona
Objective:
To determine the importance of dust transported from the surrounding
deserts on the mass loadings measured in the Phoenix area,
Institutions:
Investigators
ARE - ESRL Jack L. Durham
AMAD - ESRL Ken Scherer
EPA - LV Jeff Van Ee
IIT Research Institute - Richard Snow, Jean Graf, and
Ronald Draftz.
P. Durham, J. Frazier, and L. Quinn (EPA student aids)
EPA Project Officer: Jack L. Durham
Progress:
During November, 1975, airborne and ground-level dust samples were
collected for the purpose of characterizing the types and sources of
suspended dust impacting Phoenix. Wind profile measurements were also
made.
Dust concentrations measured with hi -volume filters averaged 203
for samplers located 30 to 20 meters above ground level. Dust concentrations
ranged from 130 ug/m^ to 30 yg/m3 measured 30 to 500 meters above ground
level. The dust concentrations decreased with height.
The dust particles were identified by optical and electron microscopy.
The majority of particles contributing to the high dust concentrations were
minerals -- feldspars, quartz, calcite, mica, and clays. Carbonaceous
particles from auto exhuast and rubber tire particles were also present as
minor components in every samples, even those collected in sparsely populated
rural areas.
The size, composition, and concentrations of these dust particles,
combined with meteorological data, indicate that the particle souces
were predominantly local to the sampling sites. Vehicular traffic, and to
some extent farming, are judged to be the primary contributors to the high
dust concentrations in Phoenix. Particles from industrial sources were
insignificant.
6. Publications ana Presentations:
1. Graf, J., R.H. Snow, J.L. Durham, and K.L. Scherer. Morphology of
Airborne Dust in Marcopia County, Arizona. Presented at: AAAS
Meeting, Denver, February 1977. To be published in Proceedings.
2. Suck, S., E. Upchurch, and J. Brock. Dust Transport in Maricopa
County, Arizona. Presented at AAAS Meeting, Denver, February 1977,
To be published in Proceedings.
3. Graf, J., R.H. Snow, and R.G. Draftz. Aerosol
Phoenix, Arizona. (EPA-600/3-77-015 February,
Institute, Chicago). 136 pages.
7. PIans: Project is complete.
Sampling and Analysis
1977). IIT Research
52
-------
1. Task Title: Analytical Support for Aerosol Studies
2. Objective:
Provide or arrange for the analysis of ambient aerosol samples
collected in the field and adapted existing analytical analysis
techniques to aerosol samples.
3. Institution: Environmental Protection Agency, Aerosol Research Branch
Investigator: R.K. Patterson; Joe Frazier and Kevin Peterson(Student Aids)
4. EPA Project Officer: Ronald K. Patterson
5. Progress:
An ion chromatograph was installed and modified with an automatic
sampling system. This system is being used to determine the SO];, SOo,
NO^, NOJ}, Br~, Cl~, NH^, Na+,and K+ content in ambient aerosols.
Progress is being made on determining the organic carbon content
of fractionated ambient aerosols using a temperature programmable
furnace and a flame ionization detector system. The major setback
in this effort has been finding a collection medium which does not
interfer with the analysis.
Other analytical techniques such as Proton-induced X-Ray Emission
and Computerized High Resolution Mass Spectrometry have been evaluated
through grants.
6. Publications, Presentations. Theses: See Winchester and Crittenden grants.
7. Plans:
1. Release RFP for an "Analytical Support for Aerosol Studies" contract,
in order to relieve our equipment of approved routine techniques.
2. Continue to research our ion chromatography capabilities as they
relate to ambient aerosols.
3. Continue to pursue a suitable technique for determining organic
carbon in fractionated ambient aerosol samples.
53
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A. ATMOSPHERIC PROCESSES AND EFFECTS
3. Visibility and Radiation Effects. Measurement of pertinent
aerosol properties and determination of relationships between concentration,
composition, size and effects.
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712.
54
-------
1. Task Title: Opticle Effects of Atmospheric Aerosol
2. Objective:
To develop experimental and analytic techniques for understanding
sources of aerosol particles and their integral optical effects.
3. Institution: University of Washington, Seattle, Washington
Investigator: A. P. Waggoner
4. EPA Project Officer: T.G. Ellestad
5. Progress:
Condensed water interacts with aerosol particles in ways that
depend on the molecular nature of the particles. Using this interaction,
instruments were designed that measure the scattering behavior as a
function of relative humidity to determine the molecular form of SO^
when it is present as a major constituent of the fine particle mass.
$04 (as H2S04 or
US haze, and
the time.
was found to dominate midcontinent rural
was found present as acid sulfate approximately one half
These results were obtained at a single site near St. Louis in 1973,
and at three sites in rural Michigan, Missouri and Arkansas in 1975.
An instrument was constructed to facilitate making these measurements.
The form of the sulfate aerosol (salt or acid) was shown to be related
to long range transport in that marine tropical air from South and East
was predominately acidjand air from the North and West was predominately
salt.
The almost continuous SQq domination at all three sites indicates
that the rural haze is the product of a multitude of sources covering
an area larger than one SO^ removal/SOo oxidation distance. These
results have direct bearing on such suojects as S0£ control via tall
stacks or via scrubbers, and the sources of rural and urban $04.
Experimental measurements have been made of SC^ oxidation rate in
solution with Q£ and 0^ under a range of temperatures and pH. The
study showed that the rates of conversion of S02 to $04 measured in
plumes are consistent with 03 solution oxidation rates which should
exist in warm clouds.
Publications:
1. Larson, T.V., R.J. Charlson, E.J. Knudson, G.D. Christian and H.H.
Harrison. 1975. The Influence of a SOo Point Source on the Rain
Chemistry of a Single Storm in the Puget Sound Region. Water Air and
Soil Poll. 4.
2. Vanderpol, A.M., F.D. Carsey, D.S. Covert, R.J. Charlson and A. P.
Waggoner. 1975. Aerosol Chemical Parameters and Air Mass Character
in the St. Louis Region. Science, 190: (7 Nov).
55
-------
3. Waggoner, A.P., A.H. Vanderpol, R.J. Charlson, T.V. Larsen, L.
Granat and C. Tragardh. 1976. Sulfate as a Cause of Tropospheric
Haze. Nature. 261(13 May).
4. Porch, W.M., D.S. Ensor, R.J. Charlson. 1975. Visibility of
Distant Mountains as a Measure of Background Aerosol Pollution. Applied
Optics. 14.
5. Weiss, R.V., A.P. Waggoner, R.J. Charlson, N.C. Ahlquist. Sulfate
Aerosol: Its Geographical Extent. Science. In Press.
6. Bolin, B., R.J. Charlson. 1976. On the Role of the Tropospheric
Sulfur Cycle in the Short-Wave Radiative Climate of the Earth. AMBIO.
5(2).
7. Covert, D.S., R.J. Charlson, R. Rasmussen, H. Harrison. 1975.
Atmospheric Chemsitry and Air Quality. Reviews of Geophysics and
Space Physics. 13(3).
8. Scheutzle, D., D. Cronn, A.L. Crittenden and R.J. Charlson. 1975.
Molecular Composition of Secondary Aerosol and Its Possible Origin.
Env. Sci. and Tech. 9(9).
Plans:
1. To conduct field experiments in the Oregon-Washington area this
fall to define the magnitude of impact and help identify sources of urban
and rural aeroso^ in this region.
2. Laboratory and field experiments are being designed to investigate
the role of urban emissions in altering the nature and persistence of
high humidity hazes and fogs. Data to be examined include the: relation-
ships between the aerosol concentration of Pb, S0|, Fe and optical
absorption to determine the source and nature of materials that may cause
heating of air aloft and altering stability; role of long range transport,
RH, temperature, incidence of rainfall along trajectory as these affect
S0| acid/salt character of the aerosol; character of visibility distri-
butions from airports and other sources as a function of site location
to determine the causes of reduced visibility.
56
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A. ATMOSPHERIC PROCESSES AND EFFECTS
4. Heterogeneous Reactions. Measurement of the rates and mechanisms
of reactions involving gases with surfaces or condensed phases.
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712.
57
-------
1. Task litie: The Role of Gas-Solid Interactions in Air Pollution,
2. Objective:
To assess the importance of heterogeneous surface reactions of gas-
eous pollutants such as S02 with constituents of urban aerosols and ground
level surfaces in the urban environment,
3. Institution: The Aerospace Corporation, Los Angeles, California
Investigator: H, Judeikis
4. EPA Project Officer: J.L. Durham
5. Progress:
Measurements have been made on the capacities for S02 removal over
various solids (Table 1). The dependency of reactivities and capacities
on various experimental conditions have been examined and surface reaction
products have been analyzed. Measured capacities ranged from several
tenths of a gram of S0£ removal per gram of solid for materials such as
MgO and MnO (particularly for humidified reaction mixtures)-to several
milligrams of $03 per gram of solid for materials such as charcoal.
Both reactivities and capacities were found to be generally independent
of S02, 02, and total pressures. Reactivities were found to be generally
independent of relative humidity; capacities were not. Capacities
measured with humidified reaction mixtures were frequently an order of
magnitude greater than those found for dry mixtures. X-ray photoelectron
(ESCA) and wet chemical techniques identified sulfate as the only sulfur-
containing surface reaction product.
Laboratory measurements have been made of deposition velocities for
S02 at ground level surfaces (Table II). The apparatus used accounts for
gas-phase mass transport of S02 so that obtained values are due solely to
the physical and/or chemical processes responsible for SO^ removal at the
surface. Here also, removal was found to accur via capacity limited
reactions. Results show the dependencies of reactivities and capacities on
S02, O^, total pressure, and relative humidity were qualitatively similar
to those discribed above.
Also examined was the potential role of additional environmental
factors on S02 removal. Pre-treatment of selected solids with dilute am-
monia (or NaOH) was found to enhance initial reactivities by a factor of
approximately 5, while pre-treatment with dilute ^804 (HC1) reduced
initial reactivities by one order of magnitude.
In order to remove soluble sulfates, several solids were washed with
distilled water after their reactivity toward SO? was completely expended
(footnote 3 of Table 1). This treatment restored initial reactivities
within experimental error, thus suggesting that precipitation could restore
the reactivity of ground-level surfaces in the actual environment.
6. Publications, Presentations, Theses:
1. Judeikis, H.S. Heterogeneous Removal of 502 ^rom tne Atmosphere.
Presented at: 8th Aerosol Technology Meeting, Chapel Hill, NC, October
6-8, 1975.
58
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2. Judeikis, H.S. and T.B. Stewart. 1976. Laboratory Measurement of SCL
Deposition Velocities on Selected Building Materials and Soils. Atmos.
Environ. 10:769.
3. Judeikis, H.S. Heterogeneous Interactions of Atmospheric SCL.
Presented at: Workshop on the Chemistry of Atmospheric Sulfur,
Philadelphia, PA, October 12-14, 1976.
Plans:
1. To complete and publish work on S02 in SOp-O^-Np-HpO mixtures.
2. Begin studies on the addition of ammonia and/or hydrocarbon + NO to
the reaction mixtures. x
59
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Table I. Reactivities and Projected Atmospheric Rates for
Heterogeneous Removal of SO-
SO_ Removal
%/hour
_ _ _
1.0 x 10"3 32
-4
;_v^o 5. 5 x 10 18
-4
Mojave Fly Ash 5. 0x10 16
A12O3 4. 0 x 10"4 13
MnO2 3.0 x 10"4 10
Pb02 7.0 x 10"5 3
Charcoal 3. 0 x 10"5 1
NaCl 3.0 x 10"6 0. 1
MnCl, <1.0xlO"6 <0.03
3 6
River Bend Fly Ash <1.0xlO <0.03
<£ is the fraction of SO_-solid collisions that lead to SO_ removal.
Projected atmospheric removal rates assuming an urban aerosol loading
of 100 //g/m having the same reactivity as the indicated solid.
3
Measurements on this material as received indicated a high sulfate
content and low reactivity. Experiments on the same material after
washing with distilled water to remove soluble sulfates gave a
reactivity comparable to that measured for Mojave Fly Ash.
4
20-30% uncertainty
The data is for metal exposure to SO,,. With prolonged exposures,
the reactivities gradually diminish and ultimately approach zero,
indicating S0» removal occurs by capacity limited reactions.
60
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Table II. Deposition Velocities for SO- Removal
. - Deposition Velocity
Material cm/sec
3 -4
Cement -I 3.2 x 10 2. 5
3 -4
Ready Mix Cement 2.6x10 2.0
Exterior Stucco - I 2.3xlO"4 1.8
Cement - H3 2.0xlO"4 1.6
Exterior Stucco - II3 1. 1 x 10"4 0.86
Adobe Clay Soil 8.4xlO"5 0.66
Sandy Loam Soil 8.3x10" 0.65
-6
Asphalt 5. 1 x 10 0. 04
Roman numerals indicate different sources for the materials used.
is the fraction of SO_-solid collisions that lead to SO_ removal.
£ Lt
3
Cured.
61
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1. Task Title: Structure and Reactivity of Adsorbed Oxides of Sulfur and
Other Small Sulfur-Containing Molecules.
2. Objectives:
To determine the structure and reactivity of adsoroed oxidos of sul-
fur and other small sulfur-containing molecules which nay exist on atmos-
pheric aerosols.
3. Institution: Texas A&M University, College Station, Texas
Investigator: J.H. Lunsford
4. EPA Project Officer: J.L. Durham
5. Progress:
It has been observed that under rather mild conditions, sulfur dioxide
undergoes a variety of surface reactions. One such reaction occurs between
S02 and magnesium oxide. On the basis of spectroscopic data, it is evident
that sulfite ions are readily formed on the surface, and that except at elevated
temperatures of more than 200°C, it is not possible to oxidize these to the
sulfate form with molecular oxygen. A limited number of these sulfite ions
may, however, be photochemically oxidized to SO; ions on the surface of mag-
nesium oxide in the presence of adsorbed water vapor and oxygen or nitrous
oxide.
The reaction between H?S and molecular oxygen or air was carried
out at 25°C over magnesium oxide, MnNaY and NaY zeolites, and amorphous
silica-alumina. The surface products, as determined by X-ray photoelectron
spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy,
were different on each of the surfaces. On magnesium oxide sulfide ions2
elemental sulfur, and sulfite ions were observed, as well as S,~ and S20~
ions. Only elemental sulfur was formed on the zeolite samples, and no
reaction products were detected on the amorphous silica-alumina. Clearly,
it is difficult to form 504 from HUS at moderate temperatures using molecular
oxygen as an oxidizing agent.
Although these experiments indicate the difficulty in oxidizing a
reduced form of sulfur to sulfate ions, it is possible to do so provided
the correct catalyst is used. The oxidation of S02 has been catalyzed, for
example, by manganese ions in aqueous solution. SO- may be oxidized to
sulfate ions by hydrated Mn2+ ions in MnNaY zeolites and on amorphous
silica alumina.
Nitrogen dioxide has been found to be a more effective oxidizing
agent than molecular oxygen. At pressures of several torr, N02 is capable
of oxidizing S0? to S07 at 25°C on the surface of silica gel and amorphous
silica alumina. Nearly monolayer coverages are obtained after several hours
of reaction. The XPS spectrum of the S(2p) and N(2p) lines for sulfur and
nitrogen on the surface of silica gel and in ammonium sulfate are depicted
in Figure 1.
62
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5. Progress (cont'd):
Results show that the radical anions So and S^O were also formed as
by-products of the reaction on magnesium oxide. It appears that elemental
sulfur from the Claus reaction, probably in the form of S~> reacts with
lattice oxide ions of MgO yielding S?0". The same ion could also be
formed by ultraviolet irradiation of adsorbed COS or CSp.
The formation of H9S~ was detected using EPR spectroscopy. This ion
may be produced by the Tow temperature reactions of hLS with trapped elec-
trons on the surface of MgO. The EPR spectrum was previously attributed
to the HpS" ion; however, using sulfur-33 labelled FLS, we demonstrated
that the paramagnetic molecule contained two non-equivalent sulfur atoms.
6. Publications, Presentations, and Thesis:
1. M.J. Lin and J.H. Lunsford. 1975. Photooxidation of Sulfur Dioxide
on the Surface of Magnesium Oxide. J. Phys. Chem. 79:892-897.
2. M.J. Lin and J.H. Lunsford. 1976. Electron Paramagnetic Resonance
Evidence for the Formation of S90~ on Magnesium Oxide. J. Phys. Chem.
80:635-639. ^
3. M.J. Lin and J.H. Lunsford. 1976. An EPR Study of H9S ~ on Magnesium
Oxide. J. Phys. Chem. 80:2015-2018. ^ L
4. M.J. Lin. Structure and Reactivity of Sulfur-Containing Molecules
Adsorbed on Magnesium Oxide. Ph.D. Dissertation, Texas A&M University, TX.
7. Plans:
1. To investigate the formation of sulfate ions on surfaces, starting
with reduced forms of sulfur and oxidizing agents such as molecular
oxygen, ozone and nitrogen dioxide.
2. To emphasize the quantitative aspects of these surface reactions.
63
-------
10.0 -
7.5
5.0-
•o
x
to
Z
O
O
2.5-
40.0
30.0
20.0
10.0
U.Or
J I I L
13.0 -
12.0-
10.0
174 170 166 406 402 398
BINDING ENERGY (,v)
Figure 1. S(2p) and N(ls) photoelectron lines from (a) silica gel
exposed to S02 and N02 and (b) (NH4)2$04.
64
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1• Task Title: Structure and Reactivity of Adsorbed Oxides of Sulfur.
2. Objective:
To develop photoelectron and infrared spectroscopy as a technique
for studying oxides of sulfur on aerosols.
To determine the mechanism for the oxidation of S02 to SO, on
surfaces.
To identify ions such as S^O" which may be produced during the
photochemical reaction of H?S wfth S02 on magnesium oxide.
3. Institution: Texas A & M University, College Station, Texas
Investigator: J.H. Lunsford
4. EPA Project Officer: J.L. Durham
5. Progress:
The past year has been devoted to photoelectron studies of sulfur
species on pure oxides, collecting flyash samples from the River Bend
Power Plant, and collecting atmospheric aerosols which were near the
Labadie Power Plant in St. Louis. In order to identify surface species
by photoelectron spectroscopy, the energy of the emitted photoelectron
must be converted into a binding energy for sulfur. This is not a
simple problem since most of the samples of interest are insulators
ana cnarring effects become serious. By employing a standard of gold
evaporated onto the samples, along with an electron flood gun, binding
energies with an error less than ±0.5 eV have been obtained. It has
also been necessary to develop computer programs for smoothing and
deconvolution of the data.
A study of S02 and hLO adsorbed on MgO/Mg(OH)2 confirms our
earlier conclusions, basea on infrared spectra, that surface sulfite
ions are formed at 23°C. The deconvoluted photoelectron spectrum of
this species is compared with the spectrum of elemental sulfur, Sg,
in Fig. la and Ib. Heating the sample in 02 at elevated temperatures
(200°C) was required for the oxidation of surface sulfite ions to
sulfate ions.
The Riverbend flyash sample revealed that most of the sulfur exists
on the surface as sulfate ions (Fig. 2a). A number of other elements
were detected in a broader scan of the flyash.
An unsmoothed spectrum from an aerosol sample collected in St.
Louis shows that two types of sulfur are present; one is a sulfate
ion and the other resembles an inorganic sulfide ion or an aromatic
sulfide (Fig. 2b). The samples also contained nitrogen in the form
of ammonium ions, which is consistent with the results of other
laboratories.
Limited progress has been made in determining the mechanism for
the oxidation of S02 to SO^ on surfaces. In stack gases, NO may be
65
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the oxidant rather than CL. In an effort to investigate this possibility
SCL and NCL were sequentially adsorbed or coadsorbed on MgO, and the
surface spears were identified by infrared and ohotoelectron spectroscopy.
Preliminary results indicate that the adsorption of SO- first (yielding
surface sulfite ions), followed by gxposure to NCL resulted in the
partial oxidation to SO* ions at 25 C; however, coadsorption did not
yield a more oxidized fo>m of sulfur. This may be explained by the fact
that NOp adsorbs as ions which are not capable of oxidizing SCL, whereas,
molecular NCL oxidizes the surface sulfite to sulfate ions. As indicated
previously, molecular oxygen is not capable of oxidizing sulfite ions at
room temperature.
SCL and H0 were found to react at
25°C
on magnesium oxide, forming
a parama"gnetic'~species which has been identified at S^O". Hyperfine
splitting due to sulfur-33 was used to confirm the identification. The
previously studied S,~ ion is also formed. Thus the Glaus reaction
yields elemental sulfur in the form of S?, S.,...Sfi, ...S molecules.
The Sp molecules react with surface oxide ions, forming SLO". This
requires a degassed MgO surface for its formation, but it is stable
presence of air.
ion
in the
Publications, Presentations, Theses:
1. A paper is scheduled to appear in the Journal of Physical Chemistry.
2. A review of the literature on adsorbed oxides of sulfur has been
completed and will be published.
Plans:
1. To develop photoelectron spectroscopy as a technique for studying
atmospheric aerosols and for following in the laboratory the oxidation
of SCL on surfaces.
2. To focus on the mode of oxidation of SCL to SCL or SCH on surfaces
by investigating the reactions which occur Tn thin aqueous films on metal
oxide surfaces. Silica and alumino silicates will be investigated using
both CL and NpO as oxidants. On pure surfaces it is anticipated that
the oxidation reactions will be slow; however, introducing transition
metal ions should catalyze the reactions. Work will continue on the sur-
face analysis of atmospheric aerosols.
66
-------
169.0 168.0 167.0 166.0 165.0 164.0 163.0 162.0
BINDING ENERGY IN EV
Figure 1. Photoelectron spectra of sulfur 2p: (A) elemental sulfur, Sg, (B) 863 ions on MgO.
67
-------
COUNTS/CHANNEL
o -n
3 '
o -u
K :r
|s
2 o
o o
3 D
-^
CD
O
r+
S
O
c_
-*l
c
-1
NJ
T3
Crt
O
o
03
3-
CD
CO
O
Q.
o
tc
Q.
en
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en
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en
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— 169.0
— 169.1
161.6
68
-------
1. Task Title: Reactions of Sulfur Dioxide in Aerosols.
2. Objective:
To measure the extent of reaction of sulfur dioxide in aerosols,
particularly as influenced by PH and various catalysts.
3. Institution: The University of Texas at Austin, Austin, Texas
Investigator: D.M. Himmelblau
4. EPA Project Officer: J.L. Durham
5. Progress:
Various models have been set up to represent the mass transfer and
reactions of sulfur dioxide with aerosol particles. Reaction rate coeffi-
cients have been calculated based on the available literature. However,
due to the varying set-ups of previous investigators, it is difficult to
predict reaction rate coefficients for the experiments to be carried
out in this investigation. About four orders of magnitude difference have
been determined from one experiment to another from the articles in the
literature.
A reaction tube has been set up with adjustable residence times so
that the reactions of sulfur dioxide with the aerosols can be measured
under controlled conditions. Particle size distributions have been
measured for two aerosol generators and various supplementary parts of
tne equipment have been assembled.
Since the amount of sulfur that is accumulated in the aerosol par-
ticles is so small, radioactive sulfur-35 will be used to determine the
overall transfer to the aerosol particles.
6. Publications and Presentations, Theses: None
7. Plans:
1. To complete the assembly of all the experimental apparatus.
2. To test the individual components.
3. To calibrate the various pieces of equipment.
4. To establish that aerosols of known size can be transmitted through
the reaction section and caught in the sampling filter without
substantial losses.
5. To estimate the reaction rate coefficients by using radioactive sulfur
dioxide.
69
-------
1. Task Title; Mass Transport Models
2. Objective:
Develop a mathematical model of the absorption of S0? by water and compare
with experimental results.
3. Institution: Northrop Services. Inc., RTF, NC.
Investigator: John Overton
4. EPA Project Officer: J.L, Durham
5. Progress: In order to model the absorption of a gas by a liquid, several
factors must be taken into consideration: (1) diffusion or transport
processes within the aerosol, (2) transport of gas through the gas-liquid
interface, (3) the chemistry of the species within the liquid.
The absorption of S0£ (at ppm concentrations) by pure water is a
very simple system with respect to the above factors. This is because
only a few products are formed in the water by the S02 and only one (rever-
sable) kinetic equation is necessary to describe the significant chemical
reactions. Further, this reaction is sufficiently fast in both directions
to be considered instantaneous; i.e. equilibrum maintained point wise within
the liquid. The reaction is:
S02£ 2 H30+ + HS03-
where S02P is the liquid phase SOp (^503).
Because of the chemical equilibrium, and the fact that
«[HS03~] (for tne particular experimental conditions considered the con-
centration, [HS03~], wnicl1 makes up over 99% of the dissolved $03, approximately
satisfies the molecular diffusion equation without chemical reaction terms.
i.e.,
a[HS03-]
D = diffusion coefficient.
The effect of the chemistry is taken into account by the gas-liquid
interface boundary condition. This condition is that the current, J, at
the interface is,
= _ D 3[HS03-] = k {[S02g] - H[S02£]
3X
where
k = a mass transfer coefficient,
H = Henry's law constant
[S02^]i = interface value of [502^1
[S02g] = gas phase value of S02-
70
-------
- p
assuming charge neutrality one finds that [S02«-] = K'1 [HS03~] :
K = chemical equilibrium constant. Thus, at the interface,
The experimental data simulated is for a bulk water system and was
taken from P.P. Terraglio and R.M. Manganelli, The Absorption of Atmospheric
Sulfur Dioxide by Water Solution's, JAPCA, 17(6), June 1967..
In the experiment, 20 Petri dishes, each with water to the same level,
were placed in a chamber. S02 was introduced into the chamber and kept at
a constant level. Approximately every six minutes a dish was removed and
analysed for the quantity of dissolved SC^, Thus a set of data, dissolved
S02 versus time, was obtained. For purposes of the model, the essence of
the experimental setup is illustrated in Figure 1.
Numerical simulations of the model are compared to the experimental
data in Figure 2. The diffusion coefficient (D) and transfer coefficient
(k) were varied to produce the best fit. The values used for the plots
in Figure 2 are D = 1.5 x 10~4cm2/sec and k = ,75 cm/sec, (D is too high
by a factor of 10, which indicates mixing in the liquid by means other
than molecular diffusion).
Assuming the water thickness = 1 urn, D = 10~5 cm2/sec, and R = 1,
an insight into the relative importance of the factors that would be
important in aerosols was obtained. Figure 3 is a plot of the fractional
saturation concentration of HSOs" in the interface and in the liquid as
a function of time. As can be seen, for times greater than 10~2 second.
the surface and average values are essentially the same. This behavior
indicates a nearly spatially uniform distribution of HS03~. Tn-is condition
is equivalent to an infinite diffusion coefficient. Thus the major
factors to be considered are the chemistry and the resistance to transport
through the air-liquid interface.
6. Publications, Presentations and Theses: None
7. Plans:
The physics and chemistry of liquid aerosols are,in general, much
more complex than indicated by the model presented here. Thus, models
and programs that can handle more complicated cases are being developed.
71
-------
AIR
WATER
J = -K([S02 ] - H ' [S02£])
SURFACE OF WATER
3C
— = 0 (current = 0)
•^-BOTTOM OF CONTAINER
Figure 1 .
72
-------
GAS PHASE SO2 = 0.81 ug/m"
GAS PHASE S02 -- 2.54 ug/-,V3
a
UJ
00
a.
o
as
<
z
O
§
t£
u.
Q
ui
OQ
OC
O
cc
u.
GAS PHASE SO2 = 5.54 yg/m
HOURS
GAS PHASE S02 = 8.73 -
.0
.5 1.0
HOURS
HOURS
1.5
i i i i i i i—rn—rr~l
Figure 2. SIMULATION OF THE ABSORPTION OF S02 BY WATER (EXPERIMENT: +;
SIMULATION: - )
73
-------
LOG (time)
1.0-
IX
*
X
GAS-LIQUID
INTERFACE VALUE
AVERAGE VALUE
O AVERAGE
WITH D = co
-3
--4
r—
"5 CT5
X
-6
-7
O
cn
x i
.3 .4 .5 .6
TIME (sec)
Figure 3. FRACTION OF SURFACE AND AVERAGE CONCENTRATIONS OF
DISSOLVED S02 (: HSO^) IN H20 OF DEPTH = 1 y
74
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A. ATMOSPHERIC PROCESSES AND EFFECTS
5. Technique Development. Development of new instruments or
techniques required for the aerosol research program.
Funded by USEPA, ORD, OALWU. Program Element 1AA603 and 1AD712,
75
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1- Task Title: Formation of Atmospheric Aerosols - Nonideal Characteristics
of Impactors.
2. Objective:
To study the nonideal characteristics of single-stage and cascade impactors
that are important for their correct application in aerosol sampling. Both
laboratory and commercial impactors have been studied.
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: W.E. Wilson
5. Progress:
In a thesis study by A.K. Rao, the performance of the impactor stages
was found to be significantly affected by the nature of the aerosol and the
collection surface. With dry, solid surfaces or dry, solid aerosols, bounce
and blowoff was severe. Liquid aerosols or liquid-coated collector surfaces
were close to the Marple theory in behavior. Glass fiber filter media surfaces
reduced bounce, but significantly changed the impactor characteristics. Whatman
filter paper collection surfaces did not reduce particle bounce appreciably.
Experimental studies of slotted impactors by Willeke show that they per-
form with a sharpness of cut close to the theoretically predicted value,if
used unaer the conditions of the numerical mode. Sideways flow entrance
and impaction onto a fibrous surface may change the collection efficiency
considerably (Figure 1).
6. Publications, Presentations, Theses:
1. Rao, A.K. An Experimental Study of Inertia! Impactors. Ph.D.
Thesis. Mechanical Engineering Department, University of Minnesota, MN,
June 1975.
2. Rao, A.K. and K.T. Whitby. Nonideal Collection Characteristics of
Single-Stage and Cascade Impactors. Accepted by Am, Ind. Hyg. Assoc. J.
1976.
3. Willeke, K. and J.J. McFeters. 1975. The Influence of Flow Entry and
Collecting Surfaces on the Impaction Efficiency of Inertial Impactors,
J. Colloid Interface Sci. 53:121-127.
4. Marple, V.A. and K. Willeke. Inertial Impactors: Theory, Design and
Use. In: Fine Particles: Aerosol Generation, Measurement, Sampling, and
Analysis (6.Y.H. Liu, ed.), pp. 411-446, Academic Press, New York, 1976.
5. Will eke, K. 1975. Performance of the Slotted Impactor. Am. Ind.
Hyg. Assoc. J. 36:683-691.
76
-------
7. Plans:
Work on the nom'deal behavior of impactors and cyclone samplers will
continue in the Particle Technology Laboratory under the direction of
Dr. B.Y.ri. Liu.
77
-------
100
90-
80-
70-
60
50
40
30
20
/
10-
i i i i i r
ARB POLYETHYLENE STICKY FILM
DOWCORNING OIL-COATED
GLASS PLATE
GLASS FIBER FILTER
(GELMAN TYPE A)
GLASS PLATE
O IIOpmPSL
O 0794pm PSL
A 0 790pm PSL
-------
1. Task Title: Sources and Trace Metals in Urban Aerosols
2. Sub-Task Title: Development and Application of Analytical and Sampling
Techniques
3. Objectives:
To develop a sensitive elemental analysis and sampling technique
capable of handling very small samples.
4. Institution: Department of Oceanography, Florida State University
Tallahassee, Florida" 32306
Investigator: John W. Winchester
5. EPA Project Officer: Ronald K. Patterson
6. Progress:
The Jensen-Nelson sampler (Streaker") was developed and has
been applied successfully to various aerosol studies. The samples
consist of strips of 0.4um pore size Nuclepore filter firmly
attached to frames. The sampler is simply a siiding-sucking ori-
fice moved by a clock motor at the rate of 1 mm/hr along the length
of the filter so as to draw about 1 liter/min of air through a
continuously-moving 2 mm x 5 mm rectangular area of the filter.
The device is positioned in the field so that the air is drawn
upward from the under-side of the filter thereby excluding particles
30 urn and larger.
In the analysis laboratory, the sample is moved automatically
for successive bombardments by a stepping motor drive with electric
control. The analysis techniques used on these samples are Proton-
Induced X-Ray Emission (PIXE) and Proton Elastic Scattering Analysis
(PESA) which yield elemental composition using the proton beam of a
Van de Graaff accelerator. Under routine PIXE analysis conditions,
85 bombardments, corresponding to a week of sampling time are currently
performed in four hours of accelerator time. Other combinations of
filter pore size, orifice area, and orifice speed can be introduced.
For urban atmospheres, however, the loading obtained with the above-
mentioned design is optimum: giving routine detecting limits in the
order of 10 - 100 ng/nP for sulfur and heavier elements by PIXE; and
sensitivity sufficient to measure lighter elements by PESA.
For both PIXE and PESA analyses, the proton beam is collimated
to a rectangular area of 2 mm x 5 mm and inside the streak. The X-
rays or the scattered protons are detected at backward angle and
give rise to a pulse-height spectrum resolvable into the individual
elements in the sample. With this arrangement, the time resolution
is 2 hours.
New collection surfaces for the Battelle-type cascade impactor
were designed so that size fractionated aerosol samples could be
analyzed by PIXE and PESA techniques. For special sampling needs
two larger stages were designed for the Battelle sampler which allows
the collection of 16.0, 8.0, 4.0, 2.0, 1.0, 0.5, 0.25, and <0,25ym
particles.
79
-------
Proton-induced X-ray emission analysis has been shown to be a
fast, inexpensive, reliable, and convenient method for routine multi-
elemental trace analysis. The major component procedures of such an
analysis are sample preparation, bombardment, and analysis of pulse-
height spectra. To meet the dual goals of a rapid and an unambiguous
analytical technique, each of the component procedures must be opti-
mized. As part of this grant sub-task title, a status report was
written on the optimization of PIXE pulse-height spectra analysis.
This analysis was based on a model of the radiation environment in
which an energy dispersive detector is placed in PIXE analysis; and
on the intrinsic characteristics of the detector. The present model
has been coded in the Fortran program, REX. The parameters of the
model are sought using a least squares minimization.
7. Publications:
1. J.W. Nelson, B, Jensen, G.G. Desaedeleer, K.R. Akselsson, and
J.W. Winchester. 1976. Automatic Time Sequence Filter Sampling
of Aerosols for Rapid Multi-element Analysis by Proton Induced
X-Ray Emission. Advances in X-Ray Analysis. 19:415-425.
2. H.C. Kaufmann, K.R. Akselsson, and W,J, Courtney. 1976, REX:
A Computer Program for PIXE Spectrum Resolution of Aerosols,
Advances in X-Ray Analysis. 19:355-366.
3. B. Jensen and J,W. Nelson. Novel Air Sampling Apparatus for
Elemental Analysis. In: Proc. 2nd Intl , Conf. Nucl , Methods in
Environ. Res., Columbia, MO, July 1974, Report Issued October, 1975.
4. T.B. Johansson, R.E. Van Grieken, J.W, Nelson, and J,W. Winchester.
1975. Elemental Trace Analysis of Small Samples of Proton-Induced
X-Ray Emission. Anal, Chem. 47:855-860.
5. J.W. Nelson and D.L. Meinert. 1975, Proton Elastic Scattering
Analysis-A Complement to Proton-Induced X-Ray Emission Analysis of
Aerosols. Advances in X-Ray Analysis. 18:598-605.
6. J.W. Nelson, J.W. Winchester and R. Akselsson, Aerosol Composition
Studies Using Accelerator Proton Bombardmen. In: Proc. 3rd Conf.
on Appl. Small Accelerators, Vol. 1, CONF-741040-P1 , USERDA, Denton,
Texas, October 1974.
7. R. Akselsson, J.W. Nelson, and J.W. Winchester. 1975. Proton
Scattering for Analysis of Atmospheric Particulate Matter. Bull. Am.
Phys. Soc., 20:155 and Conf. Proc. (In Press).
8. H.C. Kaufmann and R. Akselsson. 1975. Non-Linear Least Squares
Analysis of Proton-Induced X-Ray Emission Data. Advances in X-Ray
Analysis. 18:353-361.
80
-------
9. R.E. Van Grieken, T,B. Johansson, K.R. Akelsson, J.W, Winchester,
J.W. Nelson, and K.R. Chapman, 1976. Geophysical applicability of
Aerosol Size Distribution Measurements Using Cascade Impactors and
Proton Induced X-Ray Emission, Atmospheric Environment. 10:571-576.
10. T.B. Johansson, R.E. Van Grieken, J.W, Nelson, and J.W. Winchester.
1975. Element Trace Analysis of Small Samples by Proton-Induced X-Ray
Emission, Analytical Chemistry, 97:855.
11. T.B. Johansson, R.E. Van Grieken and J.W, Winchester, Interpretation
of Aerosol Trace Metal Particle Size Distribution. In: Proc. 2nd InH.
Conf. Nucl. Methods in Environ. Res., Columbia, MO, July, 1974. Report
Issued October, 1975.
8. Plans:
This grant is complete. A final report is forthcoming.
81
-------
1. Task Title: Formation of Atmospheric Aerosols - Development of a Sulfur
Aerosol Analyzer.
2. Objective:
To develop an instrument to continuously measure aerosol sulfur at
ambient atmospheric concentrations using a commerical flame photometric
elector and a newly developed pulsed electrostatic precipitator.
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: W.E. Wilson
5. Progress:
An instrument which combines a pulsed electrostatic precipitator
and a flame photometric detector to measure ambient sulfur aerosols has
been developed. A laboratory version of the instrument is currently
operating and will be used to measure sulfur aerosol concentrations in
the Los Angeles freeway study. The present instrument configuration
will detect sulfur aerosols down to T-Z yg/m^ as sulfur. A heater
located upstream of the instrument will be used to discriminate between
sulfuric acid and other sulfur aerosols.
6. Publications, Presentations, Theses:
1. Kittelson, D.B., R.I. McKenzte, B.Y.H. Liu, D.Y.H. Pui and F.D. Dorman.
Natrottal Bureau of Standards/University of Minnesota Stflfur Particle Analyzer
Project, EPA-IA6-P5-0684, PfBS/EPA Energy/Environment Project, semi-annual
report from NBS to EPA Off fee or Energy, Minerals.,, and Industry. Washington,
D.C., Z0460
82
-------
1. Task Title: Simultaneous Comparison of the Electrical Aerosol Analyzer
and the Diffusion Battery for Atmospheric Aerosol.
2, Objec'cives: To make simultaneous performance evaluations of the
Electrical Aerosol Analyzer (EAA) and the diffusion battery (DB) while
sampling atmospheric aerosol.
3. Institution: University of Paris
Investigator: J. Bricard
4. bPA Project Officer: T. Ellestad
5. Progress:
In preparation for making size distribution measurements with
diffusion battery and condensation nuclei counter (CNC), the CNC's response
as a function of particle size was studied with sodium chloride nuclei
produced by a Liu generator. Contrary to the existing literature, the
CuC response showed a marked dependence on particle size below 0.06 ym
diameter. The phenomenon was observed both for expansion-release counters
using water as the condensing fluid and for continuous-flow counters
employing Duty! alcohol. This finding has important implications
beyond size distribution reduction from diffusion batteries: previous
estimates of coagulation coefficients, nucleation rates, and other ultra-
fine aerosol behavior may need revision.
6. Publications, Presentations, and Thesis: None
7, Plans:
1. Compare performances of the EAA and the diffusion battery on
laboratory-generated aerosol.
2. Compare size distributions of atmospheric aerosol as measured by
the EAA and the diffusion battery.
83
-------
1. Task Title: Determination of Sulfate Ion Concentrations in Human and
Animal Serum using High Pressure Liquid Chromatography
2. Objective:
To develop a simple means of measuring human and animal serum
sulfate concentrations in subjects which have been exposed to aerosol
sulfate and sulfite pollution.
To determine if increased exposure to aerosol sulfates necessarily
results in an increased sulfate concentration in blood serum or if
other reactions occur.
These projects are being done in cooperation with Dr. E. Sawicki.
3- Institution: Environmental Protection Agency, ESRL, ARB
Investigator: L.L. Spiller and R.F. Reardon (student aid)
4. EPA Project Officer: W.E. Wilson
5. Progress:
The serum sample is dialyzed using Fisher dialysis tubing (cat.
no. 8-667D). This is done to prevent the large proteins in the serum
from damaging the column of the chromatograph. Other methods for
removing these proteins have changed the results of the analysis.
The sample is analyzed for sulfate on the high pressure liquid
chromatograph (hPLC).
A blank made from the deionized water used in dialysis is run on
the HPLC.
A first attempt at analyzing human and rabbit serums have yielded
results which were well within the range of expected values and were
very promising.
6. Publication, Presentation, Theses: None
7. Plans:
Current plans include analysis of samples which have been "spiked"
with very high levels of Na^SC^ ^$03 and NaNO£ in order to determine
the efficiency of the procedure and to see if the serum proteins react
in any way with the added ions.
84
-------
1- Task Title: Comparison study of data collected with the dichotomous
and high-volume samplers.
2- Objective: To meet the requirements for a masters thesis and to
establish a data base from which the Aerosol Research Branch
can make recommendations to other agencies and interested
individuals regarding the use of these samplers.
3. Institution: University of North Carolina, School of Public Health,
Chapel Hill
Investigator: Tim McCarthy (student aid).
4. EPA Project Officer: W.E. Wilson
5. Progress: Samples were collected from January through March, 1977, on the
roof of the EPA Monitoring station (Cameo Bldg.) in downtown Durham. The
dichotomous samples have been analyzed and the analysis of the hivol
samples are in progress.
6. Publications, Presentations, and Theses: None
7. Plans: To complete comparison study by July, 1977.
85
-------
1. Task Title: A Cyrogenic Procedure for Concentrating Rating Trace
Gases in the Atmosphere
2. Objective:
To determine the distribution, atmospheric loading, sources and
sinks of halogenated compounds; the effect of fluorocarbons on the
depletion of ozone.
3. Institution: EPA-ERC, ESRL-ARB
Investigator: L.L. Spiller, M. Miller
4. EPA Project Officer: W.E. Wilson
5. Progress:
Detection of small concentrations of gaseous air pollutants has
been achieved by the use of the fourier transformer spectrometer,
nitrogen-colled photo-detectors and infrared paths of 400 meters or
more. For measurement of many of the trace gases on the ambient air,
a detection sensitivity of 10~10 atmos. or better required. To
achieve such low detection, the pollutants have to be concentrated by
separating them from the nitrogen, oxygen and water vapor. Cyrogenic
condensation followed by distillation thus appeared to be the most
feasible technique for concentrating pollutants. Results were obtained
on 14 days between January and July 1975.
Fluorocarbon -11 values ranged from about 1.3 x 10" atmos. at
RTP, NC to 8 x 10-10 atmos. at New York City.
6. Publications, Presentations, Theses:
Infrared Measurement of Fluorocarbons, Carbon Tetrachloride,
Carbonyl Sulfide, and Other Atmospheric Trace Gases, APCA Journal, 25,
No. 12, December 1975, pages 1220-1226.
7. Plans:
To develop defining techniques for fluorocarbon F-ll, F-12, and
F-114 determination.
86
-------
1. Task Title: Collection of Atmospheric NO,, by Treated Filters
2. Objective:
Develop a simple and inexpensive method of measuring ambient
N0? levels in the atmosphere.
3. Institution: EPA-ERC, ESRL-ARB
Investigator: L.L. Spiller and G.L. Kay (student aid)
4. EPA Project Officer: W.E. Wilson
5. Progress:
The lab setup has made use of an N02 permeation tube, a tempera-
ture bath, and a bendix N02 analyzer to similate ambient NO^ concentrations
and measure filter efficiency.
Treat a specific type filter with a f^-absorbing solution. Allow
the solution to dry onto the filter.
Place the treated filter in a filter holder and use a critical
orifice followed by a vacuum pump to draw a specific flow rate of air
through the treated filter.
After exposing the filter, analyze the concentration of N02 on
the filter using a quick and accurate method such as ion chromatography.
To date, using only the Bendix analyzer, an efficiency of 94-93%
in N02 pickup has been observed using a Fisher 9-802 cellulose filter,
a triethanolamine-Sodium methoxide-5% Guaiacol solution, a humidity
range of 20-60%, and a flow rate of 350-380 cc/minute. These results
have not been confirmed using the ion chromatograph analysis.
6. Publications, Presentations, Theses: None
7. Plans:
Current plans involve confirming the efficiency by use of ion
chromatography, increasing the efficiency of the filter system to 100%.
To increase the flow rate.
To maintain high efficiency, and reduce the amount of guaiacol in
the treatment solution (the guaiacol interferes with ion chromatography
analysis).
87
-------
1. Task Title: Instrumentation for Monitoring Meteorological Data
2. Objective:
To develop a portable electronic systems to monitor wind speed,
wind direction, and temperature.
To develop systems to control pollutant samplers as a function
of meteorological parameters.
3. Institution: EPA-ERC, ESRL-ARB
Investigators: L.L, Spiller and G. DeJong (student aid)
4. EPA Project Officer: W.E. Wilson
5. Program:
A digitally programmed instrument to monitor wind speed/direction
and to selectively control up to 4 different environmental samplers
was built and is being used in field projects. Circuitry to interface
a digital tape recorder (used by the power industry to monitor power
demand) to existing meteorological instruments is being developed.
The recorder can store over 30 days of continuous time related data
on 3 channels, which can be easily transferred to a computer. This
will save much time and error involved in manually transferring data
from strip charts to computer punch cards.
6. Publications, Presentations, Theses: None
7. Plans:
Portable AC power generators, along with an AC line regulator will
be installed in the EPA mobile laboratory. These generators will enable
tne van to be used for monitoring atmospheric sulfur at locations of
high biogenic activity which are remote from human disturbances. Low
sulfur fuels will be used in the generators. A Meloy Model SA-285
Sulfur Gas Analyzer, which is capable of monitoring at 1 to 2 ppb
levels, will be used.
88
-------
1. Task Title: Improvement of "Streaker" Technique for Automated Collection
and Analysis of Aerosols.
2. Objective:
To develop a new, More effective "streaker" technique including
separation of aerosols into coarse and fine fractions.
To intercompare streaker collections - PIXE analysis with other
analytical techniques.
3. Institution: Florida State University, Tallahasse, Florida
Investigators: W. Nelson, J. Winchester, J. Oenson
4. i:PA Project Officer: W.E. Wilson
5. Progress:
A circular, 2-stage streaker which uses an impaction stage followed
by a filter to give separate collection of fine and coarse particles has
been constructed and is being tested. The series Nucleopore technique
to obtain 2-stage particle size resolution is also being tested. Streaker
results from the G,M. Sulfate Study have been compared with those of the
EPA dichotomous sampler. Satisfactory agreement (5% or better) was
found for measurement of automobile-generated sulfate.
6. Plans:
Tests will be made to determine the adequacy of using the Nucleopore
filter as a critical orifice to provide flow control.
FSU will participate in an EPA sponsored intercomparison of aerosol
measurement methods in West Virginia during Spring-1977.
7. Publications, Presentations, and Thesis: None
89
-------
B. AUTO-EXHAUST CATALYST PROGRAM
Determination of chemical and physical properties of sulfuric acid
aerosol produced by automobile catalysts.
Funded by USEPA, ORD, OHEE. Program Element 1AA601.
90
-------
"I- Task Title: Roadway Aerosol Studies During General Motors Sulfate
Dispersion Study
2. Objective:
To determine the mass flow rate of particulate sulfur during
the GM Sulfate study and derive the percent of fuel sulfur converted to
aerosol sulfur.
3> Institution: Washington University, St. Louis, Missouri
Investigators: E.S. Macias, R.A. Fletcher, J.D. Husar and R.B. Husar
4. EPA Project Officer: L.L. Spiller
5. Progress:
The fine particulate sulfur concentration was determined 15 m
from the road, at five different heights. The win velocity profile was
measured at three heights. Samples were collected at 30 min. intervals
using TWO MASS samplers. Particulate sulfur was determined by the flash
vaporization-flame photometric detection method. Samples taken before
and after the test track runs were used to correct for background sulfate
and determine the automobile contribution.
The flow rate per unit length of the roadway (Q/L) was calculated
from the fine particulate sulfur concentration as a function of: height
C (z); and the component of the velocity profile perpendicular to the
roadway U(z), according to the following integral:
Q/L = \ Cs(z)U(z) dz
The average emission rate per car/unit length of roadway can be
calculated by dividing flow rate by traffic density. The particulate
sulfur flow rate from the roadway averaged over the entire experiment
was 6.0 ± 1.2 yg/m/sec. For the traffic density of this experiment,
1.52 cars/sec, the particulate sulfur-emission rate per car was 4.0 ±
0.8 g/m (6.4 ± 1.6 mg/mile). This emission rate corresponds to a
13 ± 3% conversion of the fuel sulfur emitted as particulate sulfur
using the known fuel-sulfur content and estimated fuel consumption rate.
Publications and Presentati ons:
1. Macias, E.S., R.A. Fletcher, J.D. Husar and R.B. Husar. 1976.
Dispersion and Mass Flow Rate of Particulate Sulfur from Catalyst-Equipped
Cars. In: The GM/EPA Sulfate Dispersion Experiment: Selected EPA
Research Papers. EPA-600/3-76-035, p.81.
2. Wilson, W.E. , L.L. Spiller, T.G. Ellestad, P.O. LaMother, J.G. Dzubay,
R.K. Stevens, E.S. Macias, R.A. Fletcher, J.D. Husar, R.B. Husar,
K.T. Whitby,,D.B. Kittelson, and B.K. Cantrell. GM Sulfate Dispersion
Experiment: Summary of EPA Measurements. J. of Air Poll. Control Assoc.
In Press.
91
-------
3. Macias, E.S., R.A. Fletcher, J.D. Husar and R.B. Husar. Dispersion
and Mass Flow Rate of Participate Sulfur from Catalyst-Equipped Cars.
Presented at: Symposium on the GM/EPA Sulfate Dispersion Experiment,
Research Triangle Park, NC April 12, 1976.
4. Macias, E.S., R.A. Fletcher, J.D. Husar and R.B. Husar. Particulate
Sulfur Emission Rate from a Simulated Freeway. Presented at: American
Chemical Society Meeting, San Francisco, CA, August 31, 1976.
7. Plans:
This task is complete.
92
-------
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1. Task Title: Formation of Atmospheric Aerosols - Aerosol Size Distri-
butions and Concentrations Measured During the General Motors Sulfate
Study.
2. Objective:
To collect data on catalyst-equipped cars during October, 1975.
3. Institution: University of Minnesota, Minneapolis, Minnesota
Investigator: K.T. Whitby
4. EPA Project Officer: L.L. Spiller
5. Progress:
GM and the EPA conducted a freeway simulation study at the GM
Hi!ford Proving Ground using only catalytic converter-equipped cars.
During the study nearly 900 aerosol size distribution measurements
were made, both on and off the test track. At the same time, sulfate
and other measurements were also being taken.
For measurements on the track, a 1975 four-door sedan was equipped
with an optical particle counter, electrical analyzer, condensation
nuclei counter, and filter sulfate samplers. Samples were collected
over an 18-sec. period into an automated grab bag, where the sample
was held for the two minutes required for the measurement cycle of the
in situ analyzers. Measurements were also collected with a similar
in situ measuring system, as well as with a dichotomous sampler from
an EPA mobile laboratory located about 30 m from the roadway.
The log-normal fitting procedure was used to characterize all of
the size distributions. The amount contributed by the cars during the
test period was obtained by subtracting the averages of the background
aerosol size distributions before and after the test period from the
average during the test period (Table I).
The average volumes added to the nuclei and accumulation modes for
the car and EPA van were determined, and in both cases, about 70% of
the aerosol volume is added to the nuclei mode (Table II).
Background aerosol volume size distributions measured during the
test show three distinct modes with mean sizes of approximately 0.03,
0.24, and 6.0 ym (Figure 1). Aerosol distributions measured during
the run, both on and off the track, also exhibit three modes. Those
at 0.24 and 6.0 remain essentially unchanged while the smaller mode con-
tains more volume than the background aerosol, and now has a mean size
of about 0.02 ym (Figure 2). The exact amount of the increase in
volume of the smallest mode was greatly dependent on meteorological
parameters. The volume increase varied from about 20 ym3/cm3, when
the wind direction was parallel to the track', to 2 ym3/cm3, when the
wind blew across the track (Figure 3). On days when the wind was
parallel to the track, approximately 1/3 to 1/2 of the increase in
volume during the test runs over background appeared in the 0.24 ym mode.
No significant increase for the 0.24 ym mode was noted when the wind
blew across the track.
94
-------
Conclusions:
1. Difference distributions calculated by taking the
the average size distributions during the test and the
ground distributions before and after the test suggest
aerosol volume (and hence mass) is emitted in the size
0.1 _m.
difference between
average of the back-
that most of the
range smaller than
The geometric mean diameter by volume of this nuclei mode aerosol is
about 0.02 ym. Figure 1 compares the size distribution of aerosol measured
during the test period of GM Run 15 with the background. It is clear
that the size distribution of the accumulation mode (center mode) and coarse
particle mode (right-hand mode) have not changed significantly. It is also
clear that the nuclei mode (left-hand mode) is contributed almost entirely
by the cars on the roadway.
When the wind blows across the roadway (short aging time), most of the
aerosol contributed by the cars is smaller than 0.1 ym. When the wind blows
along the roadway (long aging time), coagulation transfers 1/3 to 1/2 of the
urn size range (Figure 3). Therefore,
0.01 to 0.1 pm size range to the 0.1 to
after emission and dilution at the tail
aerosol to the mode in the 0.1 to 1
most of the aerosol growth from the
1 um range occurs in the atmosphere
pipe.
2. The highest contributions observed on the track were during GM Run 12
on October 23 when the average wind direction during the run was 181°, or
the wind was blowing almost directly down the track (Table 1). The total
fine particle volume (VFP) contribution for GM Run 12 is 3.35 ym3/cm3 at
the trailer and 37.1 ym3/cm3 as measured
for comparison. During Run 7
7 is shown
at 197°.
by the car on the
the wind was from
inside lane. Run
the southwest,
3. The arithmetic average over the 12 GM runs for which data can be
averaged for the trailer gives means of 1.49 and 0.63 ym3/cm3 for AVAN and
AVAC respectively, or a total fine particle contribution of 2.12. A
somewhat comparable average for AVAN for the car is 7.00 ym3/cm3.
4. When the wind was blowing almost directly across the track, values of
VAN measured in the car were significantly higher on the downwind side.
For example, for GM Run 4, wind W-SW, the average values on the downwind
leg near the track were VAN - 10.1, compared to an upwind value of 4.32
ym3/cm3.
5. The geometric mean diameter by volume for the aerosol as emitted by the
cars is about 0.02 ym. When the wind was directly parallel to the roadway,
as it was for GM Run 12, coagulation increased the mean size to about 0.04,
and significant mass was transferred to the accumulation mode.
6. Correlation of particle sulfur measurements with fine particle volume
show that, within the accuracy of the measurements, the particle sulfur
can be accounted for by assuming that the aerosol is sulfuric acid in
equilibrium with water vapor.
95
-------
Publications, Presentations, Theses:
1. Whitby, K.T., D.B. Kittelson, B.K. Cantrell, N.J. Barsic and D.F.
Dolan. Aerosol Size Distributions and Concentrations Measured During
the General Motors Proving Grounds Sulfate Study. EPA-600/3-76-035.
April 1976.
2. Ibid., Submitted to: Environ. Sci. Tech. November 1976.
Plans:
1. To conduct a roadway study in Los Angeles during October
in order to measure aerosols, gases and particle chemistry.
1976
96
-------
Table I
Typical and High Average Aerosol Volumes
Measured by the Car and EPA Trailer
Measurement
Background
Test
Difference
a
VAN
.07
.05
.10
= 15
b
VAC
10.
8.
17.
12.
2
43
2
2
VAN
1
4
2
22
.96
.56
.35
.9
VAC
10
9
18
26
.4
.79
.3
.6
AVAN
1.
4.
2.
22.
88
51
25
7
AVAC
0
1
1
14
.2
.36
.10
.4
c
AVFP
2.08
5.87
3.35
37.1
Trailer GM 7
Car GM 7
Trailer GM 12
Car GM 12
a) Volume in the Aitken nuclei mode, ym /cm
3 3
b) Volume in accumulation mode, ym /cm
3 3
c) Fine particle volume = AVFP = AVAN + AVAC, ym /cm
Table II
Average Volumes Added to the Nuclei Mode
(AVAN) and the Accumulation Mode (AVAC) for
the Car Outside Compared to the EPA Van
AVAN AVAC AVTOT AVAN/AVATOT
Car
EPA Van
8.57
1.49
3.62
0.63
12.19
2.12
.70
.70
(All volumes in ym /cm )
97
-------
reee
109
Figure 1. Example of a distinctly trimodal volume size distribution
measured by the EPA trailer in situ aerosol instruments
during GMPG Run 15 on 10/29/75. The size ranges measured
by each instrument are shown. Note the excellent matching
between the instruments where they overlap. The geometric
mean sizes and geometric standard deviations are typical
of those measured during the test periods.
DURING RUN 10/29/75
— BACKGROUND AFTER RUN 10/29/79
10
100
DP(/im)
Figure 2. Trimodal model distributions measured by the EPA trailer
during GMPG Run 15 on 10/29/75. The model distributions
were obtained by fitting the data shown in Figure 1. Note
that during the test the accumulation and coarse particle
modes (center and right-hand modes) have not changed
significantly from the background conditions. On the other
hand, practically all of the volume of the nuclei mode (left-
hand mode) is contributed by the cars on the roadway.
98
-------
E
a.
Q.
Q
ill - 1 -- ! I | N ll| - 1 - 1
DIFFERENCE DISTRIBUTIONS
RUN - BKGND
A GMPG 12 ON 10-23-75
WDIR'186'
GMPG 10 ON 10-21-75
WOIR -226°
0 003
0 01
0 03
01
03
Figure 3. Shown are different distributions calculated from averages
of the size distributions measured by the car on the
roadway during the indicated runs and measurements of
background aerosol made before and after the test period.
Included in the figure are the volume (V), (V), mean
geometric size (DPG), and geometric standard deviation for
the resulting modes. These are based on a fit of the
difference data using the log-normal fitting procedures.
99
-------
1. Task Title: Sources and Trace Metals in Urban Aerosols.
2. Sub-Task Title: Freeway Aerosol Studies
3. Objectives:
Design a measurement program capable of determining trace aerosol pollutants
along roadways which can be used to evaluate: time nariation patterns of elements
analyzed; area and height dependence; extent of mixing with local and regional
components of aerosol pollutants; and baseline assessment along an urban freeway.
4. Institution: Department of Oceanography, Florida State University
Tallahassee, Florida 32306
Investigator: John W. Winchester
5. EPA Project Officer: Ronald K. Patterson
6. Progress:
Jensen-Nelson samplers ("Streakers") were placed at five locations along a
roadway running through a residential neighborhood in Tallahassee, Florida. Four
samplers were located around a nearby house, and one was located inside the house.
Samplers 1 and 2 were located 7 meters from the roadway, and 2 to 5 meters above
the ground, respectively. Sampler 3 was 7 meters from the roadway, behind a hedge.
Sampler 4 was 24 meters from the roadway and 15 meters away from an adjacent sam-
pler (#5), which was located inside a closed, air conditioned house. All samplers
were collected continuously over a one-week period on 0.4pm pore size Nuclepore
filter strips. The Streaker samples were analyzed by Proton induced X-Ray Emission
(PIXE) techniques. Each 2-hour sample collected by each Streaker underwent 85
separate analyses. The X-Ray spectra were fitted by computer and reduced for S,~"""~
Cl, K, Ca, Fe, Br, and Pb, with sensitivities between 10-100ng.
Time variations over 2-hour sampling periods showed daily variations in
Pb, Br, Fe, and Ca. Pb and Br gave constant ratios (0.235 ± 0.069) and were
correlated with traffic patterns. Fe and Ca variations followed the Pb and Br
patterns and were thought to be generated from roaddust mechanically disturbed
by automotive traffic. Sulfur and chloride did not show diurnal variation.
Chlorine concentrations were generally quite low except in sea breezes.
Table I presents the mean concentrations and standard deviations for the
elements determined at the five sampling locations. Locations 1 and 2 correlate
well and show little height differentiation. Location 3 shows the effects of
filtration by the hedge. Location 4 shows lower aerosol concentrations because
of diffusion. Location 5 shows low concentrations for all elements except
potassium,which is being generated inside the house.
Aerosol analysis of short sampling periods allows one to make conclusions
on the behavior of trace elements in the atmosphere and their potential effects
on human receptors. Elemental concentrations as a function of time and diurnal
variation patterns give evidence of local emissions (in this case for automotive
emissions), and their relationships to human activity. Because of the short
sampling times, some of this study's data show large variations which indicate
aerosol input from other sources and/or meteorological effects. Therefore, the
prediction of pollutant uptake by inhalation has to be assessed in conjunction
with the following considerations: a.) the occurrence of the elements over short
100
-------
time periods, representative of human exposure; b) the exposure of humans
relative to the cycles of their daily activity. The results of this study
have been applied to a predictive model to show the consequences of a
proposed widening of the roadway.
In another study under this sub-task title, PIXE analysis was used to
assess the aerosol sulfur baseline along an urban freeway. In September
1974, before the 1975 vehicles equipped with catalytic emission control
devices were in use, a sampling plan was developed which used six Battelle-
type cascade impactors to fractionate aerosols collected during five selected
2-hour intervals, near the San Diego Freeway in Los Angeles, these impactors
were operated simultaneously on three towers at 2 and 7 meters above road
level, 35 meters upwind, and 35 meters downwind of the traffic lanes. Par-
ticles as a function of time were sampled continuously for 100 hours from
three 7-meter heights using time-series "Streaker" filter samplers with two-
hour time resolution. All samplers were analyzed for S, Cl, K, Ca, Fe, Br,
and Pb using PIXE analysis.
Table 2 shows results from the first sampling period, 1530-1730,
Thursday, 12 September 1974, Clearly the freeway is a major source of lead,
not sulfur. Streaker data show parallel fluctuation in sulfur at all three
sites, downwind and upwind of the freeway. This supports the hypothesis that
particulate sulfur is non-automotive in origin.
The abundance of lead permits a prediction of the expected increase in
elevation of particulate sulfur concentrations along roadways when non-catalytic
automobiles burning leaded gasoline are replaced by catalytic automobiles
burning non-leaded fuel. If the following information is available . prediction
of sulfate increases will be more effective.
(1) The relative contents of lead in gasoline now and of sulfur in gasoline
to be used with catalytic converters. As a national average, both values are
about 0.05% by weight.
(2) The relative emission factors for lead and sulfate aerosol from automotive
sources.
(3) The relative particle size distributions of present automotive lead aerosol
and catalytic sulfate aerosol; their response to relative humidity, particle
coagulation during aging, and other atmospheric effects,
7. Publications and Presentations:
1. G.G. Desaedeleer, J.W. Winchester, J.O, Pillotte, J.W, Nelson, and
H.A. Moffitt. Proton Induced X-Ray Emission Analysis of Roadway Aerosol
Time Sequence Filter Samples For Pollution Control Strategy. JAEA
Conference Proceedings, Vienna, Austria, March, 1976. (In Press).
2. K.R. Akselsson, K.A. Hardy, G.G. Desaedeleer, J.W. Winchester, W.W. Berg,
T.B. VanderWood, J.W. Nelson. 1976. X-Ray Techniques For Aerosol Sulfur
Baseline Assessment Along An Urban Freeway. Advances in X-Ray Analysis ,19:415-425,
8. Plans: This grant is complete and final report will be forthcoming.
101
-------
Sampling Sites
TABLE I
Weekly mean values and standard deviation of the distribution -
expressed in ng/m and in % (standard deviation/mean value) respectively
of S, Cl, K, Ca, Fe, Br and Pb concentrations measured over one week
in two hours sampling periods.
Element
(ng/m3)
3
S 725.±360.(49.7) 689.±383.(55.6) 743.±441.(59.4)
Cl 482.±591.(123.) 414.±587.(142.) 380.±534.(154.)
K <58.± 22.(37.9) <50.± 16.(32.0) <54.± 25.(46.3)
Ca 288.±253. (87.8) 247.±143 . (57.9) 172.±115.(66.9)
Fe 156+143.(91.0 ) 147.± 88.(59.9) 126.± 75.(59.5)
Br 104.±64.(61.5) 87.+ 46.(52.9) 61.± 30.(49.2)
Pb 450.±240.(52.6) 387.±179.(46.3) 285.±134.(47.0)
4 5
S 432.+ 280. (64.8) 236.±144.(61,0)
Cl 233.±339.(146.) 111.±109.(98.2)
K <52.± 60.(115.) <203.±287. (141.)
Ca 92.+ 63. (68.5) <36.± 43. (119.)
Fe 81.± 47.(58.0) 26.± 40.(154.)
Br 38.± 16.(42.1) 15.± 7.(46.4)
Pb 174.± 80.(46.0) 63.+ 28.(44.4)
102
-------
TABLE TT
Sulfur and lead concentrations found at Freeway Sites, A, C, D,
Stage
6*
5
4
3
2
1
Size Range
<0.25
0.25-0.50
0.5-0.50
1.0-2.0
2.0-4.0
4.0-
A
1640
207
117
105
90
75
3
S ng/m
C
1680
205
211
124
102
67
3
Pb ng/m
D
1790
308
288
147
99
76
A
95
46
29
26
26
21
C
1410
145
189
237
216
40
D
1200
277
176
246
198
61
*Figures for stage 6 are not corrected for filter efficiency.
103
-------
1. Task Title: Dynamics of Automotive Sulfate Emissions.
2. Objective:
To apply an aerosol dynamic model to estimate the size and composition
of ultrafine sulfuric acid aerosols generated by catalyst-equipped automo-
biles.
3. Institution: University of Texas, Austin, Texas
Investigators: J.R. Brock, K. de Bower, and S.H,
Suck
4. EPA Project Officer: J.L. Durham
5. Progress:
A numerical model (see Task) has been applied to represent dispersion
and advection of sulfate aerosol from automobiles on a ten lane expressway
for winds perpendicular and parallel to the expressway. The automotive
sulfate aerosol interacts through coagulation with the ambient aerosol.
In addition, the size distribution changes with humidity. Through use of
a reactive dispersion model termed EPOSOD, we have also studied the
reaction of the sulfate highway plume with ambient levels of ammonia for
very stable meteorological conditions (Figure 1).
6. Puolications , Presentations, Thesis :
Suck, S.H.
Emissions.
1976.
K. de Bower and J.R. Brock. Dynamics of Automotive Sulfate
A.C.S. Symposium on Automotive Sulfate Emissions, August
Plans:
This task is complete.
104
-------
OO'OfrZ
00'OOZ
00'0
'(a)DO1O/Wa
105
-------
1. Task Title: The General Motor-Environmental Protection Agency
Sulfate Dispersion Experiment in October 1975 at the
General Motor, Milford Test Track
2. Objective:
To measure roadside sulfate exposures from a fleet of 100
percent-catalyst-equipped vehicles.
3. Institution: EPA-ERC, ESRL-ARB
Investigator: L.L. Spiller, M. Miller
4. EPA Project Officer: W.E. Wilson
5. Progress:
EPA investigators measured for sulfates, sulfuric acid, sulfur
dioxide and particle size at towers and in mobile laboratories at
several distances just off the test track. It has been established
that most of the aerosol mass emitted from the air injection catalyst
equipped vehicles was in the form of ultrafine sulfur aerosol in
the size range between 0.01 and 0.1 ym. The background measurements
before and after operation of the vehicle fleet and the ultrafine
sulfur-containing aerosol was almost completely absent.
Sulfuric acid was measured inside the equipped vehicle while
it was running in the test track. More than two-thirds of the sulfate
emitted by the vehicle was measured as sulfuric acid 20 meters off
the test track.
6. Publications, Presentations, Theses:
General Motors Sulfate Dispersion Experiment: Summary of EPA
Measurements
7. Plans:
Test is completed and results evaluated.
106
-------
1 • Task Title: Atmospheric Behavior of Catalyst-Generated Aerosols from
Source to Receptor.
2. Objective:
To predict the deposition efficiencies of sulfuric acid aerosols
(0.01 to 10 pm) in the lungs,
3. Institution: ARB-ESRL
Investigator: J.L. Durham and R. Orr (Student Aide)
4. EPA Project Officer: W,E. Wilson
5. Progress:
Catalyst-equipped automobiles emitted sulfuric acid, which nucleates
and forms sulfuric acid solution droplets in the atmosphere. Whitby made
measurements of the roadway size distribution during the GM-EPA experiment
(November 1975). He found a mode in the volume distribution with a mean
geometric diameter of 0.033 urn and geometric standard deviation of 1.6.
Such small sizes of sulfuric acid solution droplpt.s could exhibit growth
and lung deposition behavior that is different from chat of larger droplets
Calculations of growth were performed for which it, was assumed that the
final size of an inhaled droplet is determined by the dry mass of sulfuric
acid and the Kelvin equation (which relates vapor pressure to surface
curvature). The relative humidity of the lungs was taken to be 99%. The
deposition was calculated for the nasopharnyx (NP), tracheobronchial (TB),
and pulmonary (P) compartments using the ICRP values for a tidal volume
of 1450 cm3.
Typical values are given in Table 1 for the final size and acid
normality of ambient sulfuric acid solution droplets (rh = 50%) that
are inhaled (rh = 99%).
For the value of 0.035 um (n the roadway gmd), the concentration is
lowered from lli^ in atmosphere (rh = 50%) to 1N_ in the lungs (rh = 99%).
The final concentration of smaller diameters will be greater. Ambient
droplets with diameters greater than about 0.5 pm will have concentrations
of about 0.2N_ in the lungs. Thus, it should be expected that fresh
roadway sulfuric acid droplets will have a concentration of 4-25 times
greater than aged aerosol.
For Whitby's measurements, the dry sulfuric acid mass distribution
as a function of solution droplet size is shown in Figure 1 for relative
humidities of 50% and 99%. Although the increase in relative humidity
causes the droplets to grow, there is little effect on the lung deposition,
as can be seen in Table 2.
Because the sensitive tissue of the pulmonary is the receptor of
these sulfuric acid droplets, immediate action is warrented to define the
extent on health hazard.
107
-------
6, Publications, Presentations, and Thesis:
This work was presented at the ACS San Francisco, October, 1976
A full report will be published in the ORD series.
7. Plans: Project is complete.
108
-------
TABLE 1. Concentration of Droplets and Dilution Factors
Mass H.,50,
Growth Factor ct=
Relative Humidity = 50% Relative Humidity = 99% Radius at 99% Dilution
in droplet, g.
ID'18
1C'17
ID'16
ID'15
ID'14
ID'13
Radius* , um
0.0073
0.016
0.035
0.075
0.16
0.35
Mortality
13
12
11
11
11
11
Radius*,pm
0.010
0.027
0.070
0.18
0.42
1.0
Normality**
S
2
1
0.8
0.6
0.5
Radius at 50"o
1.4
1.7
2.0
2.4
2.7
2.9
Factor
0.13
0.20
0.12
0.072
0.051
0.041
109
-------
TABLE 2. Deposition calculated from the 99f^ and 50% relative
humidity sulfuric acid dry mass distributions.
Dry_Mas.s H2sn.t, mg/m3
Relative Humidity: 99% 50%
0.01 ym < D < 10 ym
Total inhaled 20 20
Pulmonary deposition 10 12
Tracheabronchial deposition 1 1
Nasopharynx deposition 2 0
Total deposition 13 13
D < 0.1 ym
Total inhaled 13 11
Pulmonary deposition 7 9
Tracheabronchial deposition 1 1
Nasophyarynx deposition 0 0
Total deposition 8 10
no
-------
APPENDIX A
ARB Projects funded by the Federal Interagency
Energy/Environment Research and Development Program
PROJECT MISTT
Direction of MISTT Field Studies, by W.E. Wilson
Management of MISTT, by W.E. Wilson
Aircraft Monitoring and Analysis for an Aerosol
Characterization Study in St. Louis, by D.L. Blumenthal .
Project MISTT Field Program, by R.B. Husar
Formation of Atmospheric Aerosols—Aerosol Characteristics
Measured at Glasgow, MO and in the St. Louis Urban Plume
during the Summer 1975, by K.T. Whitby ,
Formation of Atmospheric Aerosols—Coal Fired Power Plant
Plume Studies in St. Louis, Summer 1976, by K.T. Whitby .
Project MISTT - Synoptic Scale Haziness and Air Pollution,
by R.B. Husar
Processing and Analysis of Project MISTT Data, by
R.B. Husar
St. Louis Plume Study - Halocarbon and Hydrocarbon
Measurements, by R.A. Rasmussen
Application of Statistical and Mathematical Methods
to Air Pollution Problems, by J.H. Overton . . .
Atmospheric Boundary Layer Measurements in Project
MISTT; MISTT-II, by B. Hicks ,
Field Sampling and Analysis of Airborne Particulate
Material in Conjunction with MISTT, by P.T. Cunningham
Formation of Atmospheric Aerosols—Aerosols Produced
by Combustion, by K.T. Whitby
Aerosol Formation and Removal in Plumes, by J.R. Brock . .
Mobile Laboratory Operations in Support of Project MISTT,
July-August 1975, by T.G. Ellestad
Gas Calibration Support for 1976 MISTT Summer Field Program,
July 1976, by T.G. Ellestad
Ill
-------
Data Processing Support for 1976 Summer Field Program,
July 1976, by K. Fuchs
Relationships among Ground-level Sulfate Concentrations,
Visibility Reduction, and Meteorological Conditions,
by D. Fondario
Mesoscale Sulfate Concentration Study, by R.K. Patterson
112
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APPENDIX B
PUBLICATIONS, PRESENTATIONS, AND THESIS LISTING INDEX
1970
1. Ensor, D.S. and A.P. Waggoner. 1970. Angular Truncation Error in the
Integrating Nephelometer. Atmos. Environ. 4:481-487.
1971
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72. Winchester, J.W., D.L. Meinert, J.W. Nelson, T.B. Johansson, R.E. Van
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73. Blumenthal, D.L. and W.H. White. The Stability and Long Range Transport
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75. Desaedeleer, G.G. and J.W. Winchester. 1975. Trace Metal Analysis of
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76. Desaedeleer; G.G., J.W. Winchester, R. Akselsson, K.A. Hardy and J.W.
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77. Draftz, R.G. Similarities of Atmospheric Aerosols from Four Major
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80. Gartrell, G. and S.K. Friedlander. 1975. Relating Particulate Pollu-
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81. Gillani, N.V. and R.B. Husar. Mathematical Modeling of Air Pollution -
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82. Grosjean, D. and S.K. Friedlander. 1975. Gas-to-Particle Distribution
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83. Husar, R.B. Fine Particulate Standard: An Assessment of the need
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84. Husar, J.D., R.B. Husar and P.K. Stubits. 1975. Determination of
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85. Husar, R.B. and W.R. Shu. 1975. Thermal Analyses of the Los Angeles
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86. Johansson, T.B., R.E. Van Grieken, J.W. Nelson and J.W. Winchester.
1975. Elemental Trace Analysis of Small Samples by Proton Induced
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87. Lin, M.J. and J.H. Lunsford. 1975. Photooxidation of Sulfur Dioxide
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88. Nelson, J.W. 1975. Application of Proton Induced X-Ray Emission
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X-Ray Analysis. 18:588.
89. Nelson, J.W. and D.L. Meinert. 1975. Proton Elastic Scattering
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90. Nelson, J.W. 1975. Automatic Time Sequence Filter Sampling of Aerosols
for Rapid Multi-element Analysis by Proton Induced X-Ray Emission.
Advances in X-Ray Analysis. 19:403.
91. Nelson, J.W. 1975. X-Ray Techniques for Aerosol Sulfur Baseline
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92. Vanderpol, A.H., F.D. Carsey, D.S. Covert, R.J. Charlson and A.P.
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93. Van Grieken, R.E., T.B. Johansson, J.W. Winchester and L.A. Odom.
1975. Micro-Determination of Zirconium-Hafnium Ratios in Zircons by
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94. Vaughan, W.M., R. Sperling, N.V. Gillani and R.B. Husar. Horizontal
SOo Mass Flow. Rate Measurements in Plumes: A Comparison of Correlation
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95. Winchester, J.W. 1975. The Ocean as a Source of Particulate Matter.
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96. Winchester, J.W. Approaches to Evaluating Dry Deposition of Atmospheric
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97. Akselsson, K.R., K.A. Hardy, G.G. Desaedleer, J.W. Winchester, W.W.
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98. Boueres, L.C.S., F. Adams, J.W. Winchester, C.Q. Orsini, J.W. Nelson,
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Organization Technical Conference on Atmospheric Pollution Measurement
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99. Brock, J. 1976. Simulation of Aerosol Kinetics. J. of Colloid and
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100. Brock, J. 1976. Studies in Aerosol Dynamics: The Denver Brown Cloud.
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101. Brock, J. 1976. Simulation of Aerosol Dynamics. EPA Ecological
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102.. Brock, J. 1976. The Houston Urban Plume Study. EPA Ecological
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103. Brock, J., K. DeBower and S. Suck. Dynamics of Automotive Sulfate
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104. Brock, J. and P.B. Middleton. 1976. Dynamic Model for Urban Particu-
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105. Cunningham, P.T. and S.A. Johnson. 1976. Spectroscopic Observation
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107. Desaedeleer, G.G., J.W. Winchester and K.R. Akselsson. Monitoring
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108. Desaedeleer, G.G., J.W. Winchester, J.O. Pillotte, J.W. Nelson and H.A.
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109. Draftz, R.G. Microscopical Analysis of Aerosols Transported from
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110. Draftz, R.G. Aircraft Collection and Microscopical Analysis of Ambient
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Assoc. Meeting. Portland, OR, June 1976.
111. Draftz, R.G. Comparison of Elemental and Microscopical Analysis of
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112. Draftz, R.G. Morphology of Airborne Dust in Maricopa County, Arizona
in preparation for presentation at the 1977 AAAS Symposium on Denver
Dust. Denver, CO, February 1977.
113. Farmer, W.M. and J.O. Hornkohl. Environmental Aerosol Measurements
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114. Gillani, N.V. and R.B. Husar. Analytical-Numerical Model for Mesoscale
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115. • Gillani, N.V. and R.B. Husar. Mesoscale Model for Pollutant Transport,
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1976.
116. Gillani, N.V. and R.B. Husar. Synoptic Scale Haziness Over Eastern
U.S. and its Long Range Transport. Invited Paper: Proc. 4th National
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1976.
117. Graf, J., R.H. Snow and R.G. Draftz. Field Air Sampling Study-Phoenix,
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•118. Hardy, K.A., R. Akselsson, J.W. Nelson and J.W. Winchester. 1976.
Elemental Constituents of Miami Aerosol as Function of Particle Size.
Environ. Sci. and Tech. 10(2):176-182.
119. Husar, R.B. 1976. Therman Analysis of Aerosols. J. of Thermal
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121. Husar, R.B., N.V. Gillani and J.D. Husar. A Study of Long Range Trans-
port from Visibility Observations, Trajectory Analysis and Local Air
Pollution Monitoring Data. In: Proc. 7th Technical Meeting on Air
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122. Husar, R.B., N.V. Gillani, J.D. Husar and C.C. Paley. Large Scale
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123. Husar, R.B., N.V. Gillani, J.D. Husar, C.C. Paley and P.N. Turcu. Long
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Weather Maps and Trajectory Analysis. Preprint: Third Symp. on
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1
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Science and Technology, 82nd Nat'l Meeting of AIChE. Atlantic City, NJ,
August 30-September 1, 1976.
125. Husar, R.B., J.D. Husar, S.B. Fuller, W.H. White, J.A. Anderson, W.M,.
Vaughan and W.E. Wilson. 1976. Sulfur Budget in Large Plumes: Pollutant
Flow Rate Measurements in the St. Louis Region. Submitted to Science.
126. Husar, R.B., J.D. Husar, N.V. Gillani, S.B. Fuller, W.H. White, J.A.
Anderson, W.M. Vaughan and W.E. Wilson. Pollutant Flow Rate Measurement
in Large Plumes: Sulfur Budget in Power Plant and Area Source Plumes
in the St. Louis Region. In: Proc. American Chemical Society Meeting
(Div. of Environmental Chemistry). New York, NY, April 1976.
127. Husar, J.D., R.B. Husar, E.S. Macias, W.E. Wilson, J.L. Durham, W.K.
Shepherd and J.A. Anderson. 1976. Particulate Sulfur Analysis:
Application to High Time Resolution Aircraft, Sampling in Plumes. Atmos.
Environ. 10:591.
128. Husar, J.D., E.S. Macias and R.B. Husar. High Sensitivity Flame Photo-
metric Particulate Sulfur Analysis. In: Proc. American Chemical
Society Meeting (Div. of Environmental Chemistry). New York, NY,
April 1976.
129. Husar, R.B., E.S. Macias and W.P. Dannevik. Measurement of Dispersion
with a Fast Response Aerosol Detector. Preprint: Third Symp. on
Atmospheric Turbulence, Diffusion and Air Quality, AMS. Raleigh, NC,
October 19-22,. 1976.
130. Husar, R.B., D.E. Patterson, C.C. Paley and N.V. Gillani. Ozone in Hazy
Air Masses. Presented at: Internationl Conference on Photochemical
Oxidant and its Control. (EPA) Raleigh, NC, September 12-17, 1976.
122
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131. Husar, R.B., D.E. Patterson, W.H. White, D.L. Blumenthal and T.B. Smith.
1976. Three-Dimensional Distribution of Air Pollutants in the Los Angeles
Basin: Average vertical profiles at Hawthorne, El Monte, Ontario and
Riverside. Submitted to: J. Applied Meteor.
132. Husar, R.B. and W.H. White. 1976. On the Color of the Los Angeles
Smog. Atmos. Environ. 10(3):199-204.
133. Johansson, T.B., R.E. Van Grieken and J.W. Winchester. 1976. Elemental
Abundance Variation with Particle Size-in North Florida Aerosols. J.
of Geophysical Research. 81(6):1039-1046.
•
134. Judeikis, H.S. and T.B. Stewart. 1976. Laboratory Measurement of SO,,
Deposition Velocities in Selected Building Materials and Soils. Aero-
space report No. ATR-76(7498)-l.
135. Judeikis, H.S. and T.B. Stewart. 1976. Laboratory Measurement of
Heterogeneous Interactions of S0_. Submitted to: Atmos. Environ.
136. Judeikis, H.S. and T.B. Stewart. 1976. Lab Measurement of S02 Deposition
Velocities on Selected Building Materials and Solids. Atmos. Environ.
10:769.
137. Kaufman, H.C., K.R. Akselsson and W.J. Courtney. 1976. A Computer
Program for PIXE Spectrum Resolution of Aerosols. Advances in X-Ray
Analysis. 19:355-366.
138.' Lamb, B.K. and F.H. Shair. 1976. A Limit Model for Determining the
Impact of Rural Power Plant Emissions Relative to Urban Emissions Upon
Urban Air Quality: Part 1. Model Description and Consideration of
Long-term Impacts. Atmos. Environ. (In Press).
139. Lin, M.J. and J.H. Lunsford. 1976. Electron Paramagnetic Resonance
Evidence for the Formation of S-0~ on Magnesium Oxide. J. Phys. Chem.
80:635-639.
140. Lin, M.J. and J.H. Lunsford. 1976. An EPR Study of H_S ~ on Magnesium
Oxide. J. Phys. Chem. 80:2015-2018.
141. Macias, E.S. 1976. Atmospheric Aerosol Sulfur and Mass Concentration.
St. Louis, MO, August and September 1975. (In Press).
142. Macias, E.S., R.A. Fletcher, J.D. Husar and R.B. Husar. 1976. Particu-
late Sulfur Emission Rate from a Simulated Freeway. In: The General
Motors/EPA Sulfate Dispersion Experiment. EPA-600/3-76-035, U.S.
Environmental Protection Agency, RTP, NC, 1976. 145 pp.
143. Macias, E.S., R. Fletcher, J.D. Husar and R.B. Husar. Particulate
Sulfur Emission Rate from a Simulated Freeway. In: Proc. of Div.
of Environmental Chemistry, American Chemical Society. San Francisco,
CA, August 29-September 3, 1976.
144. Macias, E.S. and R.B. Husar. 1976. Atmospheric Particulate Mass
Measurement with "Two MASS" Beta Attenuation Mass Monitor. Environ.
Sci. and Tech. 10:904.
123
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145. Macias, E.S. and R.B. Husar. A Review of Atmospheric Particulate Mass
Measurement via the Beta Attenuation Technique. In: Proc. of the
Symposium on Fine Particles. Minneapolis, MN, May 28-30, 1975.
146. Macias, E.S. and R.B.'Husar. 1975. High Resolution on-Line Aerosol
Mass Measurement by the Beta Attenuation Technique. In: Proc. of the
Second International Conference on Nuclear Methods in Environmental
Research, Vogt, J.R. (ed.) U.S. ERDA, Columbia, MO.
147. McSweeney, A. A Diffraction Technique to Measure Size Distribution
of Large Airborne Particles. EPA-600/3-76-073, U.S. Environmental
Protection Agency, RTP, NC, 1976.
148. Meinert, D.L. and J.W. Winchester. 1976. Chemical Relationships in
the North Atlantic Marine Aerosol. Submitted to: J. Geophysical
Research.
149. Miller, D.F. Smog Chamber Studies of Photochemical Aerosol-Precursor
Relationships. EPA-600/3-76-080, U.S Environmental Protection Agency,
RTP, NC, 1976.
150. Nelson, J.W., B. Jensen, G.G. Desaedeleer, K.R. Akselsson and J.W.
Winchester. 1976. Automatic Time Sequence Filter Sampling of Aerosols
for Rapid Multi-Element Analysis by Proton-Induced X-Ray Emission.
Advances in X-Ray Analysis. 19:415-425.
151. Orsini, C.Q., H.C. Kaufmann, K.R. Akselsson, J.W. Winchester and J.W.
Nelson. Variation of Elemental Composition with Particle Size in the
St. Louis Aerosol. Presented at: The International Conference on
Particle Induced X-Ray Emission and its Analytical Applications. Lund,
Sweden, August 23-26, 1976.
152. Pilotte, J.O., J.W. Nelson and J.W. Winchester. Application of,
Multi-Station Time Sequence Aerosol Sampling and Proton Induced X-Ray
Emission Analysis Techniques to the St. Louis Regional Air Pollution
Study for Investigating Sulfur-Trace Metal Relationships. In: Proceedings
of ERDA Symposium on X- and Gamma-Ray Sources and Applications. Ann
Arbor, MI, May 19-21, 1976.
153. Rasmussen, R.A. 1976. Surface Ozone Observations in Rural and Remote
Areas. J. of Occupational Medicine. 18(5):346-349.
154. Rasmussen, R.A., R.B. Chatfield and W.M. Holdren. Transport of Hydro-
carbon and Oxidant Chemistries Observed at a Rural Mid-West Site.
Submitted for publication in: Proc. of Symp. on the Non-Urban Tropospheric
Condition. Miami Beach, FL, November 10-12, 1976.
155. Rasmussen, R.A., E. Robinson and R. Chatfield. An Assessment of the
Lower Tropospheric Continental Ozone Budget. Submitted for publication
in: Proc. Int. Conf. on Photochemical Oxidant Pollution and Its
Control. Section on Causes of Urban, Suburban and Non-Urban Oxidant
Pollution. Raleigh, NC, September 12-17, 1976.
156. Richards, J.R., D.L. Fox and R.C. Reist. 1976. The Influence of
Molecular Complexes on the Photo-Oxidation of Sulfur Dioxide. Atmos.
Environ. 10:211-217.
I? A
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157. Roberts, P.T. and S.K. Friedlander. 1976. Photochemical Aerosol
Formation SCU, 1-Heptene, and NO in Ambient Air. Environ. Sci. and
Tech. 10(6):573-580. X
158. Roberts, P.T. and S.K. Friedlander'. 1976. Analysis of Sulfur in
Deposited Aerosol Particles by Vaporization and Flame Photometric
Detection. Atmos. Environ. 10:403-408.
159. Schwartz, W.E., G.D. Mendenhall, P.W. Jones, C.J. Riggle, A.P. Graffeo
and D.F. Miller. Chemical Characterization of Model Aerosols.
EPA-600/3-76-085, U.S. Environmental Protection Agency, RTP, NC, 1976.
160. Schwartz, W.E., P.W. Jones, C.J. Riggle, D.F. Miller and W.E. Wilson.
1976. Organic Characterization of Cyclohexene/NO Aerosol. Environ.
Sci. and Tech. (In Press).
161. Sheline, J., R. Akselsson and J.W. Winchester. Trace Element Similarity
Groups in North Florida Spanish Moss: Evidence for Direct Up Take of
Aerosol Particles. J. of Geophysical Research. 81(6):1047-1050.
162. Van Grieken, R.E., T.B. Johansson, K.R. Akselsson, J.W. Winchester,
J.W. Nelson and K.R. Chapman. 1976. Geophysical Applicability of
Aerosol Size Distribution Measurements Using Cascade Impactors and
Proton Induced X-Ray Emission. Atmos. Environ. 10:571-576.
163. Waggoner, A.P., A.H. Vanderpol, R.J. Charlson, T.V. Larson, L. Granat
and C. Tragardh. 1976. Sulfate as a Cause of Tropospheric Haze.
Nature. 261:120-122.
164. Weiss, R.E., A.P. Waggoner, R.J. Charlson and N.C. Ahlquist. Sulfate
Aerosol, It's Geographic Extent. 1976. Science. (In Press).
165. Wesely, M.L., B.B. Hicks, W.P. Dannevik, S.,Frisella and R.B. Husar.
1976. An Eddy-Correlation Measurement of Particulate Deposition from
the Atmosphere. Submitted to: Atmos. Environ.
166. Whitby, K.T., B. Cantrell, R.B. Husar, N.V. Gillani, J.A. Anderson,
D.L. Blumenthal, W.E. Wilson, Jr., Ibid; W.E. Wilson, Jr., R.J. Charlson,
R.B. Husar, K.T. Whitby and D.L. Blumenthal. Paper No. 76-30-06.
69th Annual Meeting of Air Pollution Control Assoc. Portland, OR.
167. Whitby, K.T., B.C. Cantrell, R.B. Husar, N.V. Gillani, J.A. Anderson,
D.L. Blumenthal and W.E. Wilson. Aerosol Formation in a Coal Fired
Power Plant Plume. In: Proc. American Chemical Society Meeting -(Div.
of Environmental Chemistry). New York, NY, April 1976.
168. White, W.H., J.A. Anderson, D.L. Blumenthal, R.B. Husar, N.V. Gillani,
S.B. Fuller, K.T. Whitby and W.E. Wilson. Formation of Ozone and
Light-Scattering Aerosols in the St. Louis Urban Plume. In: Proc.
American Chemical Society Meeting, (Div. of Environmental Chemistry).
New York, NY, April 1976.
125
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169. White, W.H., J.A. Anderson, D.L. Blumenthal, R.B. Husar, N.V. Gillani,
S.B. Fuller and W.E. Wilson. 1976. Formation and Transport of Secondary
Air Pollutants: Ozone and Aerosols in the St. Louis Urban Plume. <
Science. 194(4261):187-189.
170. White, W.H..and R.B. Husar. 1976. A Lagrangian Model of the Pasadena
Smog Aerosol. J. Air Poll. Control Assoc. 26(l):32-35.
171. White, W.H. and R.B. Husar. 1976. Comments on Chu & Seinfeld paper -
"Formulation and Initial Application of a Dynamic Model for Urban
Aerosols." Atmos. Environ. 10:85.
172. Wilson, W.E., R.J. Charlson, R.B. Husar, K.T. Whitby and D. Blumenthal.
Sulfates in the Atmosphere. In: Proc. 69th Annual Meeting of Air
- Pollution Control Ass'n. Protland, OR, June 27-July 1, 1976.
173. Wilson, W.E., R.B. Husar, K.T. Whitby, D.B. Kittelson and W.H. White.
Chemical Reactions in Power Plant Plumes. In: Proc. American Chemical
Society Meeting, (Div. of Environmental Chemistry). New York, NY,
April 1976.
174. Winchester, J.W. Assessing Air Pollution Particulate Fallout Potential
for Water Pollution in Lake Michigan. In: Proceedings of the Second
Federal Conference on the Great Lakes. Interagency Committee on
Marine Science and Engineering of the Federal Council for Science and
Technology. August 17, 1976.
175. Winchester, J.W. Sulfur and Trace Metal Relationships in Non-urban
and Marine Aerosols Studied Using Proton Induced X-Ray Emissions.
Presented at: International Conference on Particle Induced X-Ray
Emission and its Analytical Applications. Lund, Sweden, August 23-26,,
1976. . . .
176. Winchester, J.W. and J.W. Nelson. Non-urban Sulfur Aerosol Studies.
Technical Progress Report December 1975-August 1976. EPA Grant No.
R803887, U.S. Environmental Protection Agency, RTF, NC. (Contract
J.W. Winchester for reprints.).
126
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APPENDIX C
PUBLICATIONS, PRESENTATIONS, AND THESIS LISTING INDEX
1. Adams, F. 98
2. Ahlquist, N.C. 10, 11, 20, 21, 22, 27, 59, 60, 164
3. Aksellsson, R. 54, 72, 76, 97, 107, 118, 137, 150, 151, 161, 162
4. Anderson. J.A. 26, 55, 63, 125, 126, 127, 166, 167, 168, 169
5. Baker. M.B. 40, 53
6. Barsic, N. 14
7. Berg, W.W. 97
8. Bhardwaja. O.S. 27
9. Blumenthal, D.L. 26, 55, 63, 73, 131, 166, 167, 168, 169, 172
10. Boueres, L.C.S. 98
11. Brlcard. J. 58
12. Brock, J.R. 2, 3, 8, 28, 29, 43, 56, 57, 58, 99, 100, 101,
102, 103, 104
13. Cahill, T.A. 98
14. Cantrell, B. 166, 167
15. Carsey, F.D. 92
16. Cahpman. K.R. 35, 54, 68, 162
17. Charlson, R.J. 4, 6, 7, 9, 10, 11, 20, 21, 22, 27, 31, 40, 42,
46, 53, 59, 60, 92, 163, 164, 166, 172
18. Chatfield, R.B. 154, 155
19. Courtney. W.J. 137
20- Covert. D.S. 9, 10, 60, 92
21. Crow, L.W. 30
22. Cunningham, P.T. 105
23. Dannevik. W.P. 106, 129, 165
24. Davidson, C.J. 74
127
-------
25. DeBower, K. 103
26. Desaedeleer. G.G. 75, 76, 97, 107, 108, 150
27. Draftz. R.G. 77, 109, 110, 111, 112, 117
28. Durham, J.L. 78, 127
29. Ellestad, T.G. 78
30. Ensor, D.S. 1, 4, 11, 46
31. Farmer, U.M. 113
32. Fletcher, R.A. 142, 143
33. Forler. S.H. 7
34. Fox, D.L. 79, 156
35. Frank. R. 31, 42
36. Friedlander. S.K. 5, 17, 32, 34, 61, 74, 80, 82, 157, 158
37. Friscella. S. 106, 165
38. Fuller, S.B. 125, 136, 168, 169
39. Gartrell. G. 80
40. Gemma, J.L. 44
41. Graf, J. 117
42. Graffeo. A.P. 159
43. Granat, L. 106, 163
44. Grosjean. D. 61, 82
45. Gillani. N.V. 81, 94, 114, 115, 116, 121, 122, 123, 124, 130,
166, 167, 168, 169
46. Hardy, K.A. 76, 97, 118
47. Harrison, H. 12
48. Hedgpeth. H. 33, 62
49. Heintzenberg, J. 46
50. Heisler, S.L. 34
51. Herbert. J. 12
128
-------
52. Hering. S.V. 74
53. Hicks. B.B. 165
54. Hidy. G.M. 17
55. Holdren. W.M. 154
56. Hornkohl. J.O. 113
57. Husar, J.D. 84, 121, 122, 123, 124, 125, 126, 127, 128,
142, 143
58. Husar. R.B. 11, 13, 14, 20, 23, 24, 34, 63, 81, 83, 84,
85, 94, 106, 114, 115, 116, 119, 120, 121,
122, 123
59. Jensen, B. 64, 150
60. Johansson, T.B. 35, 36, 51, 54, 65, 66, 68, 71, 72, 86, 93,
133, 162
61. Johnson, P.P. 16, 41
62. Johnson, S.A. 105
63. Jones, P.M. 37, 45, 159, 160
64. Joseph, P.M. 45
65. Judeikis, H.S. 15, 33, 38, 39, 62, 70, 134, 135, 136
66. Kaufman, H.C. 54, 72, 137, 151
67. Kinzer. G.W. 25
68. Kittelson. D.B. 173
69. Kuhlman, M.R. 79
70. Lamb, B.K. 138
71. Larson, T.V. 163
72. Lawsen, D.R. 98
73. Levy. A. 44, 45
74- Lin. M.J. 16, 87, 139, 140
75. Lin, C. 40
76. Lunsford, J.H. 16, 18, 19, 41, 50, 67, 69, 87, 139, 140
129
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77. Liu. B.Y.H. 11, 14, 20, 23, 24
78. Macias. E.S. 127, 128, 129, 141, 142, 143, 144, 145, 146
79. Madelaine, G. 58
80. Marlow, N. 56, 57
81. McJilton. C.E. 31, 42
82. McSweeney, A. 147
83. Meinert, D.L. 54, 72, 89, 148
84. Mendenhall. G.D. 159
85. Mlddleton, P.B. 43, 104
86. Miller. P.P. 44, 45, 149, 159, 160
87. Miller. M.S. 17
88. Moffett, H.A. 108
89. Mueller, P.K. 9
90. Nelson. J.W. 35, 36, 51, 54, 64, 68, 72, 76, 86, 88, 89, 90,
91, 97, 98, 108, 118, 150, 151, 152, 162, 176
91. Odom. L.A. 93
92. Orsini, C.Q. 54, 72, 98, 151
93. Paley, C.C. 122, 123, 130
94. Patterson, D.E. 130, 131
95. Pilat, M.J. 4
96. Pillotte, J.O. 108, 152
97. Porch. W.M. 4, 46, 59
98. Pourprix, M. 58
99. Rao, K.V. 69
100. Rasmussen, R.A. 153, 154, 155
101. Reist, P.C. 79, 156
102. Richards. J.R. 156
103. Rlggle. C.J. 45, 159, 160
130
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104. Roberts, P.T. 157, 158
105. Robinson, E. 155
106. Russell. P.A. 47
107. Ruud, C.O. 47
108. Schoonheydt, R.A. 18, 19
109. Schwartz. N.E. 25, 44, 45, 159, 160
110. Sem, G.J. 26, 55
111. Shair, F.H. 138
112. Sheline, J. 161
113. Shepherd, U.K. 127
114. Shu, VI.R. 85
115. Sickles. J.E. 79
116. Siegel, S. 15, 33, 38, 39, 62
117. Smith. T.B. 131
118. Snow, R.H. 117
119. Sperling, R. 94
120. Spicer, C.W. 45
121. Stewart. T.B. 33, 48, 49, 62, 70, 134, 135, 136
122. Stubits. P.K. 84
123. Suck, S. 103
124. Taarit, B.Y. 50
125. Thielke, J.F. 20
126. Tokiwa. Y. 9
127. Tragardh, C. 163
128. Turcu, P.N. 123
129. Vanderpol, A.H. 60, 92, 163
130. Vanderwood. T.B. 97
131
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131. Van Grieken, R.E. 35, 36, 51, 54, 65, 66, 68, 71, 72, 86, 93,
133, 162
132. Vaughan. W.M. 94, 125, 126
133. Waggoner, A.P. 1, 6, 12, 21, 22, 27, 52, 53, 59, 60, 92,
163, 164
134. Weiss. R.E. 164
135. Wesely. M.L. 165
136. Whitby, K.T. 11, 14, 20, 23, 24, 78, 166, 167, 168, 172, 173
137. White, U.H. 73, 125, 126, 131, 132, 168, 129, 170, 171, 173
138. Willeke, K. 78
139. Williams. I. 68
140. Wilson. W.E. 25, 63, 78, 125, 126, 127, 160, 166, 168, 169,
172, 173
141. Winchester, J.W. 35, 36, 51, 54, 65, 66, 68, 71, 72, 75, 76, 86, 93,
95, 96, 97, 98, 107, 108, 118, 133, 148, 150,
151, 152, 161, 162, 174, 175, 176
142. Winter, J.W. 20
143. Uu, M.S. 29
144. Zeigler, C.S. 7
132
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/3-77-080
3. RECIPIENT'S ACCESSION>NO.
4. TITLE ANDSUBTITLE
AEROSOL RESEARCH BRANCH, ANNUAL REPORT FY1976/76A
5. REPORT DATE
August 1977
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
W.E. Wilson and C. Danskin, editors
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Environmental Sciences Research Laboratory - RTF, NC
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
1O. PROGRAM ELEMENT NO.
1AA603, 1AD712, 1AA601
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Sciences Research Laboratory - RTP, NC
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/09
15.SUPPLEMENTARY NOTES/v complementary report, EPA-600/7-77-076, describes research
activities funded by the Energy/Environment program.
16. ABSTRACT
The research program of the Aerosol Research Branch includes research grants and
contracts at institutions in many parts of the United States, in addition to an
intramural program. The purpose of these projects is to study the chemical and
physical properties of aerosols, identify the mechanisms of aerosol formation and
removal, and conduct experiments to measure these rates.
The results of the research are being used (1) to establish the contribution of
the various sources to the ambient atmospheric aerosol loading, (2) to characterize
urban, natural, and primary and secondary aerosols, (3) to develop quantitative
descriptions of the generation and removal rates associated with each major aerosol
source and sink, (4) to quantify the effects of aerosol on atmospheric chemical
reactions, and (5) as a scientific basis for recommending regulatory actions
concerned with air quality improvements.
The research projects funded under EPA's base program are described.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
*Air pollution
*Aerosols
^Research projects
13B
07D
18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (ThisReport!
UNCLASSIFIED
21. NO. OF PAGES
143
20. SECURITY CLASS (Thispage)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (9-73)
133
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