Detection of Endocrine-Disrupting Chemicals in Samples of Second Trimester Human Amniotic Fluid

Man-made chemicals that have been shown to modulate endocrine function in animal models, so-called "endocrine disrupters", are suspected to play a role in the development of male reproductive tract abnormalities and neurobehaviroal deficits in children. However in utero exposure to environmental contaminants has not been documented previously. The present study was performed to test our hypothesis that man-made chemicals can be quantified in human amniotic fluid during the second trimester. Gas chromatographic/mass spectrometric (GC/MS) analysis was performed on amniotic fluid samples (n=53) from women (n=51) undergoing routine amniocentesis with a mean (+/- SEM) age of 36.5 +/- 0.5 years and between 15 and 23 weeks of gestation. Analytes included common PCB congeners, the DDT metabolites p,p'-DDE, and o,p'-DDE as well as the pesticides: hexachlorobenzene (HCB); and the three isomers of hexachlorocyclohexane (alpha,beta and gamma-HCH). The limit of quantitation (LOQ) for PCBs was 0.01 ng/ml and for the other organochlorines contaminants is was 0.1 ng/ml. The contaminants alpha-HCH with a mean (+/- SD) concentration of 0.15 +/- 0.06 (ng/ml) and p,p'-DDE with a mean (+/- SD) concentration of 0.21 +/- 0.18 ng/ml were detected in the amniotic fluid. PCB specific congeners were detected with a much lower frequency and levels were in the range of the LOQ. Overall one in three amniotic fluid samples tested positive for at least one environmental contaminant. Therefore, we conclude that approximately one in three fetuses in the Los Angeles area are exposed to endocrine modulatory environmental contaminants in utero the consequences of which remain unknown at this time.