Urinary Concentrations of Dialkylphosphate Metabolites of Organophosphorus Pesticides: National Health and Nutrition Examination Survey 1999–2004

Emory University, Rollins School of Public Health, Atlanta, GA 30322, USA.
International Journal of Environmental Research and Public Health (Impact Factor: 2.06). 08/2011; 8(8):3063-98. DOI: 10.3390/ijerph8083063
Source: PubMed


Organophosphorus (OP) insecticides were among the first pesticides that EPA reevaluated as part of the Food Quality Protection Act of 1996. Our goal was to assess exposure to OP insecticides in the U.S. general population over a six-year period. We analyzed 7,456 urine samples collected as part of three two-year cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999-2004. We measured six dialkylphosphate metabolites of OP pesticides to assess OP pesticide exposure. In NHANES 2003-2004, dimethylthiophosphate was detected most frequently with median and 95th percentile concentrations of 2.03 and 35.3 μg/L, respectively. Adolescents were two to three times more likely to have diethylphosphate concentrations above the 95th percentile estimate of 15.5 μg/L than adults and senior adults. Conversely, for dimethyldithiophosphate, senior adults were 3.8 times and 1.8 times more likely to be above the 95th percentile than adults and adolescents, respectively, while adults were 2.1 times more likely to be above the 95th percentile than the adolescents. Our data indicate that the most vulnerable segments of our population-children and older adults-have higher exposures to OP pesticides than other population segments. However, according to DAP urinary metabolite data, exposures to OP pesticides have declined during the last six years at both the median and 95th percentile levels.

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    • "Although conducted within a farming population, the results may have implications for larger populations . For example, in the National Health and Nutrition Examination Survey, the majority of the U.S. population with no occupational exposure to pesticides displayed detectable levels of various pesticide metabolites in their urine (Barr et al., 2010Barr et al., , 2011). The BEEA study will be an important resource for future work in this area. "
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    • "Given the 1990 census data, we estimate that about one quarter of the participants in the NHANES III call-back cohort was not 20–59 years of age. Barr et al. (2011) demonstrated that adults ≥ 60 years of age tended to have higher urinary DAP concentrations than did younger adults in NHANES 2001–2004. Assuming that a similar age effect was observed in the NHANES III call-back cohort, the urinary DAP estimates presented here may overestimate those of the adult population 20–59 years of age during 1988–1994 because of the influence of samples from older adults. "
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