Early-life exposure to per- and polyfluoroalkyl substances: Analysis of levels, health risk and binding abilities to transport proteins

• Published in: Eco-Environment & Health 2024-09, Vol.3 (3), p.308-316
• Main Authors: Xu, Yaqi, Sui, Xinyao, Li, Jinhong, Zhang, Liyi, Wang, Pengpeng, Liu, Yang, Shi, Huijing, Zhang, Yunhui
• Format: Article
• Language: English
• Subjects: Binding affinity; Breast milk; Emerging PFAS; Health risk; Original; Placental transfer
• ISSN: 2772-9850; 2772-9850
• DOI: 10.1016/j.eehl.2024.04.007

Per- and polyfluoroalkyl substances (PFAS) can pass through the placenta and adversely affect fetal development. However, there is a lack of comparison of legacy and emerging PFAS levels among different biosamples in pregnant women and their offspring. This study, based on the Shanghai Maternal–Child Pairs Cohort, analyzed the concentrations of 16 PFAS in the maternal serum, cord serum, and breast milk samples from 1,076 mother-child pairs. The placental and breastfeeding transfer efficiencies of PFAS were determined in maternal-cord and maternal-milk pairs, respectively. The binding affinities of PFAS to five transporters were simulated using molecular docking. The results suggested that PFAS were frequently detected in different biosamples. The median concentration of perfluorooctane sulfonate (PFOS) was the highest at 8.85 ng/mL, followed by perfluorooctanoic acid (PFOA) at 7.13 ng/mL and 6:2 chlorinated polyfluorinated ether sulfonate at 5.59 ng/mL in maternal serum. The median concentrations of PFOA were highest in cord serum (4.23 ng/mL) and breast milk (1.08 ng/mL). PFAS demonstrated higher placental than breastfeeding transfer efficiencies. The transfer efficiencies and the binding affinities of most PFAS to proteins exhibited alkyl chain length-dependent patterns. Furthermore, we comprehensively assessed the estimated daily intakes (EDIs) of PFAS in breastfeeding infants of different age groups and used the hazard quotient (HQ) to characterize the potential health risk. EDIs decreased with infant age, and PFOS had higher HQs than PFOA. These findings highlight the significance of considering PFAS exposure, transfer mechanism, and health risks resulting from breast milk intake in early life. •6:2 Cl-PFESA exhibited a high detection rate and concentration in maternal serum, cord serum, and breast milk samples.•PFAS were more easily transferred through the placenta than breastfeeding.•With increasing carbon chain length, the placental and breastfeeding transfer efficiencies of PFAS showed a structure-dependent pattern.•The EDIs decreased with breastfed infant age and the HQs of PFOS were higher than that of PFOA. [Display omitted]