PFAS Across the Placenta and Its Potential Impact on Glucose Imbalance and Infant Growth

Per- and polyfluoroalkyl substances (PFASs) are persistent pollutants that cross the placental barrier, yet their transfer dynamics and developmental impacts remain unclear. We quantified 16 PFASs in maternal serum, cord serum, and maternal/fetal placental surfaces from 102 mother-infant pairs, calculated transfer efficiencies, and evaluated associations with neonatal growth and 12-month development. Mediation analysis assessed the role of maternal glucose regulation in linking PFAS exposure to early life growth outcomes. All 16 PFASs were detected, with mean ∑₁₆PFAS concentrations of 5.26 ng/mL in maternal serum, 3.52 ng/mL in cord serum, and 1.15 and 0.97 ng/g on maternal and fetal placental surfaces, respectively. Average transfer efficiencies were 45% (maternal to cord) and 73% (maternal to fetal surface), with several PFASs exceeding 100%. Prenatal PFAS exposure correlated with elevated maternal, fetal, and neonatal glucose and reduced postnatal growth, with maternal glucose mediating up to 23.19% of the effect, implicating glucose dysregulation a key pathway. The findings provide quantitative evidence implicating glucose-regulatory pathways in PFAS-induced maternal-fetal health effects and, using multiple matched biospecimens per mother-infant pair, offer a comprehensive view of PFAS transport across the maternal-fetal interface. A 12-month follow-up confirmed persistent growth impairment, reinforcing the need to regulate emerging PFAS and monitor metabolic outcomes.