Urinary concentrations of dialkylphosphate metabolites of organophosphorus pesticides: National Health and Nutrition Examination Survey 1999-2004

Dana Boyd Barr, Lee Yang Wong, Roberto Bravo, Gayanga Weerasekera, Martins Odetokun, Paula Restrepo, Do Gyun Kim, Carolina Fernandez, Ralph D. Whitehead, Jose Perez, Maribel Gallegos, Bryan L. Williams, Larry L. Needham

Research output: Contribution to journalArticle

46 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)3063-3098
Number of pages36
JournalInternational journal of environmental research and public health
Issue number8
Publication statusPublished - Jul 25 2011
Externally publishedYes



  • Dialkylphosphate
  • Organophosphorus
  • Pesticide
  • Urine

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis

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