Transplacental transfer efficiency of perfluoroalkyl substances (PFAS) after long-term exposure to highly contaminated drinking water: a study in the Ronneby Mother-Child Cohort

In a birth cohort with a wide range of exposures to primarily PFOS and PFHxS from contaminated drinking water, we found that the transplacental transfer efficiencies (TTE) of eight PFAS and three PFOS isomers were of considerable magnitude. The highest TTE were observed for PFOA and PFHxS, and for branched PFOS isomers compared with linear. Although we observed slightly lower TTE in mother-child dyads with high and intermediate exposures compared with dyads with background levels of exposure, the considerable TTE in highly exposed mothers implies high absolute prenatal exposure in children in contaminated areas.