Characterization and Source Apportionment

EPA Grant Number: R832415C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R832415
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Rochester PM Center
Center Director: Oberd√∂rster, G√ľnter
Title: Characterization and Source Apportionment
Investigators: Hopke, Philip K. , Prather, Kimberly A. , Gelein, Robert
Institution: Clarkson University , University of Rochester , University of California - San Diego
Current Institution: Clarkson University , University of California - San Diego , University of Rochester
EPA Project Officer: Chung, Serena
Project Period: October 1, 2005 through September 30, 2010 (Extended to September 30, 2012)
RFA: Particulate Matter Research Centers (2004) RFA Text |  Recipients Lists
Research Category: Human Health , Air


This core will provide critical information on the physical and chemical properties of ultrafine and fine aerosols to be used by health effect researchers in the other research cores. We will link state-of-the-art measurements with data analysis methods that will permit apportionment of the major source types contributing to airborne particulate matter (PM). The core will apportion particulate mater mass apportionments to support epidemiologic, toxicological, and clinical studies. We will develop methods to characterize particulate compositional changes as they are processed in the atmosphere in transit from the source to the receptor site with a focus on the identification of the chemical species contributing to the measured reactive oxygen species. We will use the data characterizing the composition of the ambient aerosol being concentrated for animal and clinical exposures in Rochester and state-of-the-art receptor models to apportion the sources of these particles.


A suite of tools will be used to characterize ambient, source, concentrated and model aerosol size and composition. Particles will be sampled at different locations (urban and remote; eastern and western US) from various sources (i.e. roadways, power plants) to assess the effects of aging on the oxidative capacity of particles and the changes in their composition during transport. In addition to on-line size-resolved, chemical characterization, particles will be studied using a variety of off-line techniques. We will develop sampling techniques using spin trap agents to stabilize oxidative radicals so their chemical structures can be identified by chromatographic/MS and EPR analysis. Using ambient measurements of specific organic compounds made at selected STN sites, source apportionments using the CMB model will be made for STN sites at which PMF studies have apportioned the aerosol mass. CMB and PMF results will be compared for the STN sites to ascertain the ability of PMF to resolve source types.

Expected Results:

The results from this core's studies will be essential to interpret the results of the other cores. These measurements will permit development of a delivery system to provide exposures of specific radical species on model particles for toxicological studies. Source apportionment of ambient PM will be made using the measured compositions of integrated particle samples, single particle size and composition data from ATOFMS measurements and particle size distributions to support epidemiological studies. The CMB-PMF results will provide a quantitative test of PMF source apportionments. We will collect ambient aerosol samples, providing them to the Toxicology Core for in vitro studies measuring particle toxicity. These results will be used to determine the relative toxicity of various species and apportioned source types.

Publications and Presentations:

Publications have been submitted on this subproject: View all 19 publications for this subprojectView all 190 publications for this center

Journal Articles:

Journal Articles have been submitted on this subproject: View all 13 journal articles for this subprojectView all 143 journal articles for this center

Supplemental Keywords:

air, speciation trends network, PM2.5, ultrafine particles, reactive oxygen species, ultrafine particles, positive matrix factorization (PMF), chemical mass balance (CMB,, RFA, Scientific Discipline, Air, particulate matter, Environmental Chemistry, Health Risk Assessment, Biochemistry, cardiopulmonary responses, chemical characteristics, fine particles, atmospheric particles, airway epithelial cells, airborne particulate matter, human exposure, aerosol composition

Progress and Final Reports:

  • 2006 Progress Report
  • 2007 Progress Report
  • 2008 Progress Report
  • 2009 Progress Report
  • 2010 Progress Report
  • 2011 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R832415    Rochester PM Center

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R832415C001 Characterization and Source Apportionment
    R832415C002 Epidemiological Studies on Extra Pulmonary Effects of Fresh and Aged Urban Aerosols from Different Sources
    R832415C003 Human Clinical Studies of Concentrated Ambient Ultrafine and Fine Particles
    R832415C004 Animal models: Cardiovascular Disease, CNS Injury and Ultrafine Particle Biokinetics
    R832415C005 Ultrafine Particle Cell Interactions In Vitro: Molecular Mechanisms Leading To Altered Gene Expression in Relation to Particle Composition