U.S. Environmental Protection Agency
Office of Research and Development
National Center for Environmental Research
Science to Achieve Results (STAR) Program


Measurement, Modeling, and Analysis Methods for Airborne Carbonaceous Fine Particulate Matter (PM2.5)

Opening Date: October 31, 2002
Closing Date: February 5, 2003

Summary of Program Requirements
Specific Areas of Interest
Standard Instructions for Submitting an Application

General Information

Program Title: Measurement, modeling, and analysis methods for airborne carbonaceous fine particulate matter (PM2.5)

Synopsis of Program:
The Environmental Protection Agency (EPA) is soliciting research grant applications that can elucidate an improved understanding of the sources and the accumulation of airborne, carbonaceous, fine particulate matter (PM2.5). EPA seeks research to develop and evaluate:

1) Carbonaceous PM2.5 measurement methods. Using advanced, comparable measurement and analysis methods for the carbonaceous fraction of ambient PM2.5,

2) Carbonaceous PM2.5 emissions sources. Using available and emerging methods to measure and speciate carbonaceous PM2.5 for major combustion source categories including fossil fuel, agricultural burning, and wildfires; and

3) Air quality processes analysis and modeling. Using available and emerging data to explain the chemical and physical transformation and transport of carbonaceous PM2.5 and improve fundamental processes for understanding air quality model development.

Contact Person(s):

Paul Shapiro, 202-564-6833; email: shapiro.paul@epa.gov
Darrell Winner, 202-564-6929; winner.darrell@epa.gov

Applicable Catalog of Federal Domestic Assistance (CFDA) Number(s): 66.500

Eligibility Information:

Academic and not-for-profit institutions located in the U.S., and state or local governments are eligible to apply for assistance under this program.

Award Information:

Anticipated Type of Award: Grant
Estimated Number of Awards: Approximately fourteen to eighteen
Anticipated Funding Amount: Approximately $6 million
Potential Funding per Award per Year: Up to $150,00 per year for up to 3 years
Limitations: Requests over $450,000 total will not be considered

Sorting Code(s):

The sorting code for applications submitted in response to this solicitation is

Deadline/Target Dates:

Letter of Intent Due Date(s): None
Application Proposal Due Date(s): February 5, 2003


The U.S. Environmental Protection Agency (EPA), Office of Research and Development (ORD), is seeking grant applications for research that would improve measurement methods, models, and analysis techniques used to quantify emissions and ambient concentrations of PM2.5. This solicitation focuses on studies that will provide insights in, and improved techniques to quantify the organic and elemental carbon fractions of, emitted and measured PM2.5 and to more fully understand the specific chemical species that make up the organic fraction.


Air pollution is a widespread problem in the United States, with over 130 million individuals exposed to levels of air pollution that exceed one or more health-based ambient standards. One of the major air pollutants of concern, particulate matter (PM), represents a broad class of chemically and physically diverse substances. PM can be described by size, formation mechanism, origin, chemical composition, atmospheric behavior and method of measurement. The concentration of PM in the air varies across space and time, and is related to the source of PM, atmospheric transformations, meteorological conditions, and other variables. PM can be principally characterized as discrete particles spanning several orders of magnitude in size, with particles falling into the following general size fractions:

  • PM10 (i.e., inhalable particles, generally defined as all particles equal to and less than 10 microns in aerodynamic diameter; particles larger than this are not generally deposited in the lung),

  • PM2.5, also known as fine particles (respirable, generally defined as those particles with an aerodynamic diameter of 2.5 microns or less, which can penetrate deep into the lungs),

  • PM10-2.5, also known as coarse particles (generally defined as those particles with an aerodynamic diameter greater than 2.5 microns, but equal to or less than 10 microns); and

  • Ultrafine particles generally defined as those less than 0.1 microns.

Fine and coarse particles are distinct in terms of their emission sources, formation processes, chemical composition, atmospheric residence times, transport distances, and other parameters. Fine particles are directly emitted from combustion sources and are also formed secondarily from gaseous precursors such as sulfur dioxide, nitrogen oxides, or organic compounds. Fine particles (PM2.5) are generally composed of sulfate, nitrate, organic and elemental carbon, chloride and ammonium compounds, and other elements or their oxides or salts. Components of fine particles change back and forth between the gas and aerosol phases making their measurement difficult by customary filter-based methods.

Combustion of coal, oil, diesel fuel, gasoline, wood, and vegetation produces emissions that contribute to fine particle formation. In contrast, coarse particles are typically generated by mechanical crushing or grinding and are often dominated by re-suspended dusts and crustal material from paved or unpaved roads, construction, farming, mining activities, and wind-blown dust. Typically, source processes that produce coarse particles also yield some fine particles. Fine particles can remain in the atmosphere for days to weeks and travel through the atmosphere hundreds to thousands of kilometers, while most coarse particles typically are deposited to the earth within minutes to hours and within tens of kilometers from the emission source.

PM2.5 has been linked to a range of serious respiratory and cardiovascular health problems. The key effects associated with exposure to ambient particulate matter include premature mortality, aggravation of respiratory and cardiovascular disease (as indicated by increased hospital admissions and emergency room visits, school absences, work-loss days, and restricted activity days), aggravated asthma, acute respiratory symptoms, chronic bronchitis, decreased lung function, and increased risk of myocardial infarction. Recent estimates indicate that exposures to PM2.5 may result in tens of thousands of excess deaths per year, and many more cases of illness among the US population.

Due to the complex nature of PM2.5, there are many scientific issues that require further inquiry to support the future efforts of air quality managers who are responsible for designing cost-effective implementation strategies to reduce exposure to harmful levels of PM2.5 across the country. EPA has several emission control plans, such as the NOx SIP Call (https://www.epa.gov/airmarkets/fednox/index.html), that will be implemented over the next several years. In addition, EPA is proposing the Clear Skies Initiative, a major, multi-pollutant control program that is expected to greatly reduce the sulfate portion of PM2.5. However, current models predict that there will be areas that will violate the PM2.5 National Ambient Air Quality Standard (NAAQS) even after significant further emission controls from the NOx SIP Call and Clear Skies (https://www.epa.gov/clearskies/). Thus, the focus of this RFA is on carbonaceous PM2.5, which is expected to be a significant contributor to PM2.5 in areas that are predicted to continue to violate the NAAQS.

The research needs supported by this RFA have been identified in reports produced by the National Research Council (NRC) and NARSTO. These needs are briefly described below.

In its second and third reports on "Research Priorities for Airborne Particulate Matter," the NRC Committee on Research Priorities for Airborne Particulate Matter recognized the importance of implementation-related research and established the following topics and key questions which this solicitation addresses:

  • Characterization of Emission Sources (NRC Research Topic 3): What are the size distribution, chemical composition, and mass-emission rates of particulate matter emitted from the collection of primary-particle sources in the United States, and what are the emissions of reactive gases that lead to secondary particle formation through atmospheric chemical reactions?

  • Air Quality Model Development and Testing (NRC Research Topic 4): What are the linkages between emission sources and ambient concentrations of the biologically important components of particulate matter?

This RFA also includes development of improved ambient measurement methods that are inherent within the NRC topics described above and analysis of data from recent major field programs. Further information about the NRC recommendations on PM research priorities can be obtained at http://www.nap.edu/catalog/10065.html Exit and http://www.nap.edu/catalog/9646.html. Exit

NARSTO's Strategic Execution Plan, Part 4: Science Plan for Suspended Particulate Matter, February 2001 (http://www.cgenv.com/Narsto/strategicplan.html) Exit provides further information to potential applicants on research needs. In addition to describing the further research investment needed in each of these areas, the science plan describes in detail the fine particle research effort, its importance, and its timing for several activities related to this RFA.


Since it is likely there are multiple mechanisms responsible for the observed health effects from PM2.5, and different source types (anthropogenic and biogenic) are responsible for emitting particle or gaseous precursors of concern, a comprehensive effort is needed to ensure that a full suite of tools is available to support the wide range of analyses that will be needed. The emission estimation methods and models must be robust enough to characterize all types of sources operating under a range of conditions at various spatial and temporal scales and the air quality models must be able to address the range of meteorological conditions, chemical transformations, and transport issues that will occur at national, regional and local scales. Further, these tools must be assessed using real-world monitoring data. Data from recent intensive field studies in selected areas of the country (e.g., EPA Supersites: https://www.epa.gov/ttn/amtic/supersites.html) are becoming available and provide a significant resource for use in research funded by this RFA. The science generated through this RFA will build the foundation to produce and evaluate these improved tools to address the range of PM source mixes, chemical transformations, and transport.

Given the potentially wide scope of research in these areas, it is necessary to provide some focus. The focus of this RFA is carbonaceous PM2.5. Carbonaceous PM is composed of two major components: organic carbon, which is made up of hundreds of individual organic compounds, and elemental carbon, which is also referred to as soot, black carbon, or light-adsorbing carbon. Together, organic and elemental carbon comprise 20-70% of PM2.5 mass nearly everywhere in the country. When available, organic tracer species of carbonaceous PM2.5 are a powerful means to match source signatures with ambient measurements to determine the relative importance of emission sources (e.g., Schauer et al., 1996).

Areas of research for this RFA:

1. Carbonaceous PM2.5 measurement methods

Our ability to measure the individual organic compounds in the ambient air is greatly restricted because of a variety of factors. As a result, only 10-20% percent of the organic compounds in ambient PM2.5 have been identified and quantified as individual species. Some of the prime difficulties are collection methods that are prone to interferences from gas-phase species, incompatibility in analysis methods, and lack of reference materials and calibration standards suitable for elemental carbon, organic carbon, and individual organic species. As a result, research is needed to answer the following questions:

  • What methods can be developed and evaluated that will significantly, reliably, and at reasonable cost, improve our ability to collect, identify, and quantify a greater number of organic species in PM2.5, including polar organic compounds, and/or semi-volatile organic species?

  • What new, organic, aerosol tracers for important PM2.5 sources can be identified and quantified in ambient samples? Research could include identification of new species, improved methods that reduce the time and effort required to analyze complex organic samples, and/or investigations that explore the regional differences in tracers and sources.

As in section 3A below, EPA seeks proposals that utilize data from the EPA Supersites Program and/or other intensive field study monitoring data, looking across multiple regions, to answer questions such as:

  • What conditions influence the ability of methods employed at monitoring sites across the country to accurately and reliably measure ambient carbonaceous PM2.5?

2. Characterization of carbonaceous PM2.5 emissions from combustion sources

EPA seeks proposals to better elucidate the sources of carbonaceous PM2.5. Current models predict there will be counties in the U.S. that violate the PM2.5 National Ambient Air Quality Standard (NAAQS) even after implementation of significant further emission controls (i.e., NOx SIP Call, Clear Skies). Carbonaceous emissions from combustion sources will contribute significantly to the remaining levels of PM2.5 in these areas. In order to better identify and characterize combustion sources that produce carbonaceous PM2.5, EPA seeks research that uses available and emerging methods to measure and speciate carbonaceous PM2.5 for major combustion source categories (including fossil fuel and vegetative burning) to answer the following questions:

  • What are the rates and species of carbonaceous PM2.5 emitted from fossil fuel, agricultural burning, and wildfires as determined by the most cost-effective available and emerging methods, and how do changes in fuel loads and other conditions influence these emissions?

  • What unique source profiles can be identified and characterized for major combustion sources and fuels for use in receptor-oriented modeling?

Studies addressing the questions above will support the broad needs of the atmospheric science community and will generate results that can be used to improve existing and future emission models that will provide improved estimates of time- and space-resolved emissions of PM2.5 and PM2.5 precursors for use in air quality models.

3. Air quality processes analysis and modeling

As elaborated in the NRC's Research Priorities for Airborne Particulate Matter (http://www.nap.edu/catalog/9646.html) Exit , understanding the relationships between emission sources and ambient concentrations of PM2.5 requires progress in both receptor-oriented models (see section 3A), which estimate source contributions to airborne PM2.5 through linking emission source profiles with ambient measurements, and source-oriented models (see section 3B), which predict airborne PM2.5 concentrations by simulating chemical and physical processes coupled with emission data.

A) EPA seeks proposals using receptor-oriented models and data analysis tools, especially proposals that use data from the EPA Supersites Program and/or other state-of-the-art monitoring data such as that from the speciation network and other intensive field studies. The EPA Supersites Program includes intensive and long-term monitoring and measurement programs at seven locations across the United States (New York, Baltimore, Pittsburgh, St. Louis, Houston, Fresno, and Los Angeles). Two major intensive monitoring programs were established in July 2001 and January 2002 across the eastern half of the United States. All Supersites data will be compiled in the NARSTO Permanent Data Archive. Data from the eastern intensives will be compiled in a separate, relational database referred to as the Supersites Integrated Relational Database (SIRD). Details regarding SIRD, the Supersites Program, and individual Supersites Projects are available at https://www.epa.gov/ttn/amtic/supersites.html. Currently, SIRD contains test data in the directory system, a comprehensive list of all measurements made, and links to Supersite data.

EPA seeks research that utilizes the rapidly expanding resources of ambient measurements, looking across multiple regions, to answer such questions as:

  • What is the relationship of local and regional emissions to locally observed carbonaceous PM2.5? How do urban plumes impact rural air quality? How do the concentrations of ambient PM2.5 and PM2.5 precursor species in background air influence urban air quality?

  • What is the relative importance of emission sources and atmospheric processes in the accumulation of carbonaceous PM2.5 in specific regions of the US? How do the sources and processes affect the interplay between ozone and PM formation? How does the relative importance differ among US regions? What are the implications for effective reductions in ambient carbonaceous PM2.5? Proposals that use the conceptual model approach (Pun and Seigneur, 1999) are encouraged. Proposals that compare the source attribution resulting from receptor-oriented models, source-oriented models, and ambient data analysis are encouraged.

B) Comprehensive, source-oriented models capable of accurately predicting observed PM2.5 are emerging, including processes for secondary aerosol formation. Such models will be required for implementation planning to attain the new National Ambient Air Quality Standards (NAAQS) for PM2.5. While versions of these models are already available and in use, improvements to the model processes, along with the emissions improvements discussed above, would significantly enhance the outputs from the models and lead to more credible predictions of PM concentrations. As with the other areas of interest, the focus of research should be on understanding the impacts on ambient PM2.5 concentrations due to the sources of carbonaceous PM2.5, including improvements in the ability of source-oriented models to simulate the formation of secondary organic aerosol.

EPA seeks proposals to address the following key air quality modeling questions and research needs:

  • What new modules can be developed that improve our ability to accurately simulate ambient carbonaceous PM2.5 concentrations (including secondary organic aerosol) through accounting for: 1) the phase transition between gases and aerosols for semi-volatile compounds, 2) aqueous and heterogeneous chemical processes, and 3) alternative aerosol representations (such as external mixtures of particles)? Modules that are compatible with the Community Multi-scale Air Quality (CMAQ) model (https://www.epa.gov/asmdnerl/models3/cmaq.html) are especially encouraged. Proposals must include model evaluation using appropriate laboratory or ambient measurements (e.g., EPA Supersite, speciation or other field-study monitoring data).

  • What techniques can best be used in numerical air quality models to attribute the components of carbonaceous PM2.5 to the specific sources that emitted them or their gaseous precursors?


B. K. Pun and C. Seigneur, Understanding particulate matter formation in the California San Joaquin Valley: conceptual model and data needs, 1999, Atmospheric Environment, 33, 4865-4875.

J. J. Schauer, W. F. Rogge, L. M. Hildemann, M. A. Mazurek, G. R. Cass, and B. R. T. Simoneit, 1996. Source Apportionment of Airborne Particulate Matter Using Organic Compounds as Tracers, Atmospheric Environment, 30, 3837-3855.

NARSTO's Strategic Execution Plan, Part 4: Science Plan for Suspended Particulate Matter, February 2001 (http://www.cgenv.com/Narsto/strategicplan.html) Exit

NRC's Research Priorities for Airborne Particulate Matter Vol. II http://www.nap.edu/catalog/9646.html. Exit

NRC's Research Priorities for Airborne Particulate Matter Vol. III http://www.nap.edu/catalog/10065.html Exit

US EPA Clear Skies Initiative https://www.epa.gov/clearskies/

US EPA Community Multi-scale Air Quality model https://www.epa.gov/asmdnerl/models3/cmaq.html

US EPA Nox SIP Call https://www.epa.gov/airmarkets/fednox/index.html

US EPA Supersites https://www.epa.gov/ttn/amtic/supersites.html


It is anticipated that a total of approximately $6 million will be awarded, depending on the availability of funds. EPA seeks the most cost-effective proposals that utilize funding of up to $150,000 per year for up to 3 years. EPA encourages proposals that combine several of the research areas while staying within the maximum EPA funding contribution of $450,000, including direct and indirect costs. Requests for EPA funding exceeding $450,000 will not be considered.


Academic and not-for-profit institutions located in the U.S., and state or local governments, are eligible under all existing authorizations. Profit-making firms are not eligible to receive grants from EPA under this program. Federal agencies and national laboratories funded by federal agencies (Federally-funded Research and Development Centers, FFRDCs) may not apply.

Federal employees are not eligible to serve in a principal leadership role on a grant. FFRDC employees may cooperate or collaborate with eligible applicants within the limits imposed by applicable legislation and regulations. They may participate in planning, conducting, and analyzing the research directed by the principal investigator, but may not direct projects on behalf of the applicant organization or principal investigator. The principal investigator's institution may provide funds through its grant from EPA to a FFRDC for research personnel, supplies, equipment, and other expenses directly related to the research. However, salaries for permanent FFRDC employees may not be provided through this mechanism.

Federal employees may not receive salaries or in other ways augment their agency's appropriations through grants made by this program. However, federal employees may interact with grantees so long as their involvement is not essential to achieving the basic goals of the grant.1 The principal investigator's institution may also enter into an agreement with a federal agency to purchase or utilize unique supplies or services unavailable in the private sector. Examples are purchase of satellite data, census data tapes, chemical reference standards, analyses, or use of instrumentation or other facilities not available elsewhere, etc. A written justification for federal involvement must be included in the application, along with an assurance from the federal agency involved which commits it to supply the specified service.

1EPA encourages interaction between its own laboratory scientists and grant principal investigators for the sole purpose of exchanging information in research areas of common interest that may add value to their respective research activities. However, this interaction must be incidental to achieving the goals of the research under a grant. Interaction that is "incidental" is not reflected in a research proposal and involves no resource commitments.

Potential applicants who are uncertain of their eligibility should contact Jack Puzak in NCER, phone (202) 564-6825, Email: puzak.jack@epa.gov.


A set of special instructions on how applicants should apply for an NCER grant is found on the NCER web site, https://www.epa.gov/ncer/rfa/forms/index.html, Standard Instructions for Submitting a STAR Application. The necessary forms for submitting an application will be found on this web site.

Sorting Codes

The need for a sorting code to be used in the application and for mailing is described in the Standard Instructions for Submitting a STAR Application. The sorting code for applications submitted in response to this solicitation is 2003-STAR-C1.

The deadline for receipt of the applications by NCER is no later than 4:00 p.m. ET, February 5, 2003.


Further information, if needed, may be obtained from the EPA officials indicated below. Email inquiries are preferred.

Paul Shapiro, 202-564-6833; email: shapiro.paul@epa.gov
Darrell Winner, 202-564-6929; email: winner.darrell@epa.gov