Science Inventory

BIOMARKERS OF PM EXPOSURE TO COMBUSTION SOURCE EMISSIONS & ORGANIC (TOXIC) COMPONENTS

Contact
phone: 919-541-2433
email: coutros.katherine@epa.gov

Description:

Fine particles (PM2.5) and associated semivolatile organic compounds (SVOC) contain a very complex mixture of both organic and inorganic chemicals that may contribute to toxicity of the particles. The health effects of PM2.5 exposures in humans result from both acute and chronic exposures and include cardiopulmonary effects, cancer, and reproductive effects. Recent source apportionment-health studies support the hypothesis that combustion sources are a major source of PM toxic chemical components. A further challenge is to distinguish and apportion exposure and health outcomes to specific combustion sources (e.g., diesel sources, gasoline mobile sources, fuel oil, forest fires, wood stove, agricultural burning, cooking, etc.). ORD's Research Strategy ranks investigation of causal mechanisms, particle characteristics, and characterization of ambient particle exposures among the highest research priorities. This task is focused on the potentially toxic organic components of organic matter, including organic source tracers. Measurements of the uptake, metabolism and excretion of biomarkers of source specific organic tracers has been a powerful tool in understanding the relationship between human exposure and health outcomes. One example of the success of such exposure biomarker research is the advancement in understanding population exposures to environmental tobacco smoke through the use of personal nicotine and urinary cotinine as exposure and biomarker measures. The development of biomarkers of exposure and dose to other combustion sources is an integral part of this research as is the identification of chemicals and biomarkers that would facilitate source apportionment of exposure. This task will focus on organic chemicals, but where possible, will include simultaneous examination of metals. Organic chemicals under investigation are the polycyclic aromatic hydrocarbons (PAH) and nitro-PAH which are formed either in combustion sources or through atmospheric transformation. Other classes of organic chemicals include those that are potential source tracers (e.g., methoxylated phenols as wood combustion tracers, alkanes, hopanes, etc.) or are highly toxic, mutagenic, and/or carcinogenic (e.g., nitro-PAH lactones and quinones found in urban air). This project will interface with the following NERL Tasks: 1)Exposures to toxic components associated with PM (Causal Agents), 2) Research Methods for PM Toxic Compounds, and 3) PM Source Apportionment/Receptor Modeling of PM Toxic Compounds.

Purpose/Objective:

The objective of this task is to develop and evaluate personal exposure and biomarker methods for toxic components associated with PM2.5 and SVOC in population exposures. Specific sub-objectives include the following:

1) Identification and quantification of either toxic or tracer organic chemicals associated with PM2.5 and associated SVOC.

2) Measurement of personal airborne exposure of selected toxic/tracer organic species in population based human exposure studies.

3) Development and application of urinary metabolite and other biomarker methods for these toxic/tracer organic species in human exposure studies.

4) Evaluation of multivariant receptor models for apportioning personal exposure using biomarker data.

Record Details:

Record Type: PROJECT
Start Date: 01/01/1999
Completion Date: 09/30/2003
Record Last Revised: 03/09/2005
Record Created: 04/25/2003
Record Released: 04/25/2003
Record ID: 56197

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL EXPOSURE RESEARCH LAB
HUMAN EXPOSURE AND ATMOSPHERIC SCIENCES DIVISION
IMMEDIATE OFFICE