The Presence Of Dialkylphosphates In The Environment And Their Contribution To Characterizing And Assessing Organophosphate Pesticide Exposure.EPA Grant Number: F5D30812
Title: The Presence Of Dialkylphosphates In The Environment And Their Contribution To Characterizing And Assessing Organophosphate Pesticide Exposure.
Investigators: Quirós, Lesliam
Institution: University of California - Berkeley
EPA Project Officer: Zambrana, Jose
Project Period: August 1, 2005 through August 8, 2005
Project Amount: $107,224
RFA: STAR Graduate Fellowships (2005) RFA Text | Recipients Lists
Research Category: Academic Fellowships
Scientists have tried to link organophosphate pesticide residues in the environment and foods to doses derived from dialkylphosphates (DAPs), a collection of class-specific metabolic products for most of these pesticides, in human urine. However, large gaps of information still exist about the sources, pathways, and amounts of organophosphate exposure to children and how to properly assess and characterize these exposures. Recent studies, suggest that dialkylphosphates in urine may reflect exposure from environmental organophosphate degradation products as well as their parent compounds. If this is indeed the case, pesticide doses in urine may overestimate true pesticide exposure levels of the parent compound. The hypothesis that urinary metabolite levels may reflect coexistence of preformed DAPs in the environment as well as DAPs originating from organophosphate exposures has not been investigated. This project involves developing laboratory methods to detect dialkylphosphates in environmental media, specifically in air and dust.
The main objective of this project is to develop and validate laboratory methods to measure dialkylphosphate levels in environmental media, specifically dust and air samples.
Laboratory methods to measure environmental DAPS will be developed and validated. Methods developed will measure total DAPs consisting of six organophosphate metabolites: dimethylphosphate (DMP), dimethyldithiophosphate (DMDTP), dimethylthiophosphate (DMTP), diethylphosphate (DEP), diethyldithiophosphate (DEDTP), and diethylthiophosphate (DETP). These metabolites derive from approximately 40 organophosphate compounds, falling into the general categories of dimethyl and diethyl organophosphate pesticides.
Results from laboratory development, will directly contribute to the body of knowledge necessary to implement the Food Quality Protection Act of 1996 (FQPA) and other policies intended to protect the health of children and other susceptible populations. Specifically, the following results/impacts are expected from this project:
- Development of new laboratory methods to measure DAPs in the environment.
- Allow for more precise aggregate exposure estimates of organophosphate pesticides in urinary metabolite measurements.