Organophosphate urinary metabolite levels during pregnancy and after delivery in women living in an agricultural community

Environ Health Perspect. 2005 Dec;113(12):1802-7. doi: 10.1289/ehp.7894.


Little information has been published about pesticide exposures experienced by pregnant women. We measured six dialkyl phosphate (DAP) urinary metabolites of organophosphate (OP) pesticides in 600 pregnant, low-income women living in the Salinas Valley, California, an agricultural area. A total of 28% were employed as farm fieldworkers during pregnancy, and 81% had at least one household member who worked in agriculture. Samples were collected twice during pregnancy (mean = 13 and 26 weeks' gestation, respectively) and just after delivery (mean = 9 days). As in other studies, dimethyldithiophosphate levels were higher than those of other urinary OP metabolites. Total DAP metabolite levels in samples collected after delivery were higher than in samples collected during pregnancy. Median metabolite levels at the first and second prenatal sampling points and at the postpartum collection were 102.8, 106.8, and 227.2 nmol/L, respectively. Both prenatal and postpartum metabolite levels were higher in these Salinas Valley women than in a sample of women of childbearing age in the general U.S. population (National Health and Nutrition Examination Survey), although the deviation from U.S. reference levels was most pronounced after delivery. Higher DAP metabolite levels in the immediate postpartum period may have implications for estimating dose during pregnancy and for exposure during lactation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • California
  • Creatinine / urine
  • Environmental Exposure*
  • Environmental Monitoring / statistics & numerical data*
  • Environmental Pollutants / metabolism
  • Environmental Pollutants / urine*
  • Female
  • Humans
  • Models, Statistical
  • Organophosphates / metabolism
  • Organophosphates / urine*
  • Pesticides / metabolism
  • Pesticides / urine*
  • Pregnancy
  • Rural Population / statistics & numerical data*
  • Socioeconomic Factors


  • Environmental Pollutants
  • Organophosphates
  • Pesticides
  • Creatinine