Validating the Measurement of Environmental Chemicals in Amniotic Fluid as a Potential Biomarker of Prenatal Exposure

Brenda Eskenazi, Ph.D.
University of California, Berkeley
P30ES01896 and P01ES09605

Background: Use of pesticides in the United States, both agriculturally and residentially, has risen to over one billion pounds annually. Recent studies by this NIEHS and EPA jointly funded Children's Environmental Health Center have demonstrated widespread pesticide exposure to the U.S. population. Pregnant women and children are among those at risk for exposure. Overall, these studies confirm that children are exposed to pesticides prenatally, when they may be particularly vulnerable to adverse health effects during critical periods of development. Exposure and health research has been hampered by the lack of reliable methods to determine fetal exposure. These researchers report the validation of a method using amniotic fluid to provide direct evidence of fetal exposure to commonly used non-persistent pesticides.

Advance: Using one hundred amniotic fluid samples collected during amniocentesis at 18 weeks of gestation and slated for disposal, analytic methods were evaluated for measuring organophosphate and carbamate pesticides and metabolites, synthetic pyrethroid metabolites, herbicides, and chlorinated phenolic compounds. Six phenolic compound were found including napthol and pentachlorophenol. The organophosphate metabolites diethylphosphonate, dimethylphosphate, and dimethylthiophospadte were also detected in some samples.

Implication: Although the reported levels are low compared to reports in maternal urine and blood and meconium, they indicated direct exposure to the developing fetus possible during sensitive stages of development. These results suggest that amniotic fluid offers a unique opportunity to investigate fetal exposures and health risks.

Citation: Bradman A, Barr DB, Claus Henn BG, Drumheller T, Curry C, Eskenazi B. Measurement of pesticides and other toxicants in amniotic fluid as a potential biomarker of prenatal exposure: a validation study. Environ Health Perspect. 2003 Nov; 111(14):1779-82.