Grantee Research Project Results
2005 Progress Report: Concordance Analysis of Probabilistic Aggregate Exposure Assessment and Biomarkers of Exposure
EPA Grant Number: R831844Title: Concordance Analysis of Probabilistic Aggregate Exposure Assessment and Biomarkers of Exposure
Investigators: Kissel, John C.
Institution: University of Washington
EPA Project Officer: Aja, Hayley
Project Period: August 1, 2004 through July 31, 2007
Project Period Covered by this Report: August 1, 2004 through July 31, 2005
Project Amount: $449,193
RFA: Environmental Statistics Research: Novel Analyses of Human Exposure Related Data (2004) RFA Text | Recipients Lists
Research Category: Environmental Statistics , Human Health
Objective:
Three key areas of scientific inquiry in the study of environmental contaminants are: (1) assessment of aggregate exposure; (2) probabilistic prediction of exposure; and (3) biomarkers of exposure. The objective of this project is to integrate these three areas of inquiry through application of second order probabilistic methods to aggregate exposure data and through concordance analysis of predicted and measured levels of urinary pesticide metabolites. These analyses should provide new insights into the validity of current pesticide exposure assessment methods and a novel approach for the evaluation of pesticide exposure data.
Progress Summary:
In the first year of the project, efforts were directed primarily toward: (1) the acquisition of environmental and biomonitoring data for chlorpyrifos and its metabolite trichloropyridinol (TCPy) for the North Carolina subpopulation in the U.S. Environmental Protection Agency’s Children’s Total Exposure to Pesticides and Other Persistent Organic Pollutants (CTEPP) study; (2) development of basic residential and daycare exposure models in MATLAB®; (3) selection of appropriate behavioral exposure factors; (4) generation of probabilistic estimates of urinary TCPy; and (5) demonstration of analysis of concordance between predicted and observed results. The initial model considered exposure via dietary ingestion, inhalation, and ingestion of soil. Diet was predicted to be the dominant source (of those examined) of urinary TCPy, and direct dietary exposure to TCPy was found to account for a greater portion of urinary TCPy than was dietary exposure to the parent compound, chlorpyrifos. However, aggregate exposures underpredicted observed excretion of TCPy. A poster covering these topics was submitted to the annual meeting of the International Society of Exposure Analysis.
Future Activities:
At the end of the first year, future plans include: (1) acquisition of data from the CTEPP Ohio subpopulation; (2) quantification of the shortfall between predicted and observed urinary excretion of TCPy; and (3) inclusion of additional exposure pathways that might explain that shortfall.
Journal Articles:
No journal articles submitted with this report: View all 5 publications for this projectSupplemental Keywords:
RFA, Economic, Social, & Behavioral Science Research Program, Scientific Discipline, Health Risk Assessment, Biochemistry, Environmental Statistics, health risk analysis, risk assessment, biomarkers, aggregation, ecological epidemiology, concordance analysis, probabalistic aggregate expsoure, pesticide exposure assessment modelProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.