Exposure to Multiple PFASs during Early Pregnancy and Maternal and Neonatal Thyroid Function

摘要

Background: Prenatal exposure to per- and polyfluoroalkyl substances (PFASs) may disrupt maternal and neonatal thyroid function, which is critical for growth and neurodevelopment. Objectives: To examine associations of prenatal exposure to multiple PFASs with maternal and neonatal thyroid function. Methods: We studied 732 pregnant women and 480 neonates in Project Viva, a longitudinal pre-birth cohort in Boston, MA. We quantified six PFASs including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), and maternal thyroid hormones [thyroxine (T4), Free T4 Index (FT4I), thyroid stimulating hormone (TSH)] in plasma collected at a median 9.6 weeks gestation and neonatal T4 levels from post-partum heel sticks. We estimated associations of concentrations of single PFASs with thyroid hormone levels using covariate-adjusted linear regression models and assessed effects of exposure to multiple PFASs using multi-pollutant regression models. Results: PFASs were moderately to strongly correlated (rs: 0.19-0.74). In single-pollutant models, PFASs were not associated with maternal T4 or TSH, but PFOA, PFOS, perfluorohexane sulfonate (PFHxS), and 2-(N-methyl-perfluorooctane sulfonamido) acetate were inversely associated with maternal FT4I [e.g., -1.87% (95% CI: -3.40, -0.31) per interquartile (IQR) increase in PFOA]. Prenatal PFOS, PFOA, and PFHxS were inversely associated with T4 levels in male neonates [e.g. PFHxS, -0.46 μg/dL (95% CI: -0.83, -0.10)]. In multi-pollutant models, PFOA was suggestively inversely associated with maternal FT4I [-1.62% (-3.77, 0.57)]; in neonatal models, PFHxS [-0.36 (-0.75, 0.03)] and PFOA [-0.70 (-1.79, 0.37)] were suggestively inversely associated with T4 levels in males. Conclusions: Prenatal exposure to PFASs was inversely associated with maternal FT4I and T4 in male neonates, with evidence for confounding by PFAS coexposure. These results support the hypothesis that exposure to PFASs may influence maternal and neonatal thyroid function.