Methods for Measuring Children's Exposures to Pesticides and Other Environmental Contaminants


United States Environmental Protection Agency	Office of Research and Development

National Exposure Research Laboratory
Research Abstract

Government Performance Results Act (GPRA) Goal # 4.5.2 (old # 30204)

Annual Performance Measure #226

Significant Research Findings:

Methods for Measuring Children's Exposures to Pesticides and Other
	Environmental Contaminants	

Scientific	In August of 1996, Congress issued the Food Quality Protection Act (FQPA)

Problem and	mandating EPA to reassess pesticide tolerances for current-use pesticides. The

Policy Issues	FQPA mandates require that future risk assessments consider pesticide exposures

from different exposure routes and media including residential exposures. In
response to the FQPA mandates, the EPA's Office of Research and Development
outlined a research strategy to address selected pesticide research priorities.

EPA's research will provide better understandings of how individuals are exposed
to pesticides, the magnitude of these exposures, and what measures may be needed
to reduce future exposures.

Research	The EPA's National Exposure Research Laboratory (NERL) conducted the

Approach	Children's Total Exposure to Persistent Pesticides and Other Persistent Organic

Pollutants (CTEPP) study to investigate the exposures that young children may
have to pesticides and other persistent and non-persistent pollutants. This study
was designed to produce high quality children's exposure data that could be used
to address several of the FQPA mandates. During the study design phase, it
became clear that new and/or refined sampling/analytical methods and approaches
were needed to ensure the study produced the intended high quality data needed
for conducting the aggregate exposure assessments. In response to these needs,
NERL and its collaborators implemented a methods research program designed to
improve the sensitivity and precision of the proposed study methods. Methods
ranging from field screening methods (immunoassays) to the sophisticated and
highly sensitive analytical techniques (LC/MS/MS and chiral separations) were
developed for analyzing the target species in matrices such as air, dust and soil,
wipes, food, urine (metabolites) and drinking water. All the enhanced methods
were written in a standard operating procedure format and compiled into a single
product for use in the EPA study and by others conducting similar exposure
studies.

Results and	The results of this methods research program represent a significant step in

Impact	reducing uncertainties in children's exposure assessments. By using these tools,

EPA and other exposure researchers can provide consistently-collected, high
quality exposure data to OPP that can then be used in their FQPA mandated
reassessments. The high quality exposure data generated with these methods also
support the Agency's mission of safeguarding the environment and protecting
human health.

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Methods were developed by EPA's NERL and EPA-funded contractors working
in NERL's Human Exposure Research Program located at laboratories in
Cincinnati, OH, Las Vegas, NV and Research Triangle Park (RTP), NC. The
CTEPP study provided an opportunity for researchers to perform problem-driven
research in support of a Congressional mandate to EPA's Office of Pesticide
Programs (OPP).

The SOP collaborators on this document are:

Marsha Morgan (RTP)- CTEPP Task Order Project Officer and Principal

Investigator, contractor developed methods;

Jeffrey Morgan (Cincinnati)- EPA food methods development;

Jeanette Van Emon (Las Vegas)- EPA immunoassays for parent compounds and
their metabolites;

Andrew Lindstrom and Elin Ulrich (RTP)- EPA analytical methods (LC/MS/MS,
chiral).

QA assistance was provided by Susan Lumpkin, Linda Porter and Elizabeth Betz
in RTP.

Selected 2004 presentations and publications:

Morgan, J.N., Kauffman, P., Hieber, T.E., and Brisbin, J. Pesticide analytical methods to support
duplicate-diet human exposure measurements. Presented at: 5th European Pesticide Residue
Workshop, Stockholm, Sweden, June 13-16, 2004.

Brisbin, J., and Morgan, J.N. The determination of pyrethroid and pyrethrin insecticides in foods.
To be presented at: 2004 Florida Pesticide Residue Workshop, Orlando, FL, July 18-21, 2004.

Morgan, M.K., Sheldon, L.S., Croghan, C., Jones, P., Wilson, N.K., Chuang, J.C., and Lyu, C.
Levels of organophosphates and their degradation products in the homes, day care centers, and
urine of 127 Ohio preschool children. To be presented at: International Society of Exposure
Analysis, Philadelphia, PA, October 17-21, 2004.

Strynar, M.J., and Lindstrom, A.B. Summary of research on perfluorinated compounds at the U.S.
Environmental Protection Agency's ORD/NERL/MDAB. Presented at: Center for Disease Control,
Atlanta, GA, May 25, 2004.

Strynar, M.J., and Lindstrom, A.B. Overview of perfluorinated compound research at the U.S.
Environmental Protection Agency's NERL/MDAB. Presented at: John Hopkins University Weekly
Seminar, Baltimore, MD, March 22, 2004.

Wilson, N.K., Chuang, J.C., Lyu, C., Menton, R., and Morgan, M.K. Aggregate exposures of nine
preschool children to persistent organic pollutants at day care and at home. Journal of Exposure
Analysis and Environmental Epidemiology 13 (3): 187-202 (2003). EPA/600/J-03/451.

Wilson, N.K., Chuang, J.C., Iachan, R., Lyu, C., Gordon, S.M., Morgan, M.K., Ozkaynak, H., and
Sheldon, L.S. Design and Sampling Methodology for a Large Study of Preschool Children's
Aggregate Exposures to Persistent Organic Pollutants in their Everyday Environments. J. Expo.
Anal. Environ. Epidemiol. 2004: 14: 260-274.

Morgan, M.K., Sheldon, L.S, Croghan, C.W., Jones, P.A., Robertson, G.L., Chuang, J.C., Wilson,
N.K., and Lyu, C.W. Exposures of preschool children to chlorpyrifos and its degradation product
3,5,6-trichloro-2-pyridinol in their everyday environments. Journal of Exposure Analysis and
Environmental Epidemiology, {accepted).

Research
Collaboration and
Research
Products

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Ulrich, E.M., Cummings, T., Garrison, A.W. Chiral Analysis of two indoor contaminants. Presented
at Society for Environmental Toxicology and Chemistry Meeting, Austin, TX, November 12, 2003.

Future Research NERL is committed to providing high quality exposure data to fill critical data
gaps, replace default assumptions, and address EPA Program Office research
needs. As residential-use pesticides are replaced, NERL will conduct research and
develop the necessary tools for assessing exposures to the high-priority pesticides
and persistent pollutants. NERL will compile a readily available toolbox of
validated methods for use to address high priority exposure issues.

Contacts for	Questions and inquiries can be directed to:

Additional	Myriam Medina-Vera, Ph.D.

Information	u.S. EPA, Office of Research and Development

National Exposure Research Laboratory
Mail Code D 205-05
109 T.W. Alexander Drive
Durham, NC 27711
Phone: 919/541-5016
E-mail: Medina-Vera.Myriam@epa.gov

Federal funding for specific sections of this research was administered under EPA
contract #68-D-99-011 to Battelle by Dr. Marsha Morgan who is the CTEPP Task
Order Project Officer and Principal Investigator.

Marsha K. Morgan, Ph.D.

U.S. EPA, Office of Research and Development

National Exposure Research Laboratory

Mail Code E 205-04

109 T. W. Alexander Drive

Durham, NC 27711

Phone: 919/541-2598

E-mail: Morgan.Marsha@epa.gov

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