PBDE Exposure, Placental Transfer, and Birth Outcomes

Abstract

ISEE-664 Objective: Animal studies have suggested that prenatal exposure to polybrominated diphenyl ethers (PBDEs) may result in alterations in growth and development. A cohort study was initiated by the Columbia Center for Children's Environmental Health to examine the impact of prenatal exposures to toxicants, including PBDEs, that may have been emitted from the World Trade Center (WTC) buildings in New York City following the 9/11 terrorist attack. This report focuses on the transfer of PBDE congeners across the placenta to the fetus and the effect these exposures have on birth outcomes, including birth weight, length, head circumference and ponderal index. Materials and Methods: Between December 2001 and June 2002, maternal and/or cord blood samples were collected from 329 women delivering singletons at 3 hospitals located near the WTC site, of which 210 cord and 161 maternal plasma samples were analyzed for selected PBDE congeners. Demographic, health, and exposure information was abstracted from medical records and from a questionnaire administered after delivery. Spearman's correlation coefficients, Wilcoxon signed-rank tests, and linear regression analyses were used to evaluate these data. Results: Cord and maternal levels of BDE-47, BDE-99, and BDE-100 were highly correlated (r = 0.95, r = 0.83, and r = 0.91, respectively). However, maternal concentrations of BDE-100 and BDE-153 were, on average, significantly higher than corresponding cord levels (P = 0.02 and P = 0.05, respectively). In separate univariate and multivariate analyses, birth weight, length, head circumference, and ponderal index were not related to cord PBDE concentrations. Conclusions: Although maternal and cord concentrations are highly correlated for BDE-47, BDE-99, and BDE-100, differences between cord and maternal concentrations of BDE-153 are more apparent, indicating that this congener may not move as easily from mother to fetus. Contrary to what has been observed in toxicologic animal models, our birth outcomes appear to be unrelated to PBDE exposure. Children are being followed to assess neurodevelopmental outcomes.