Neonatal Effects of In Utero Exposure to PFAS

No associated abstract.  This is an invited conference presentation.

Impact/Purpose

Per- and poly-fluoroalkyl substance (PFAS) research is an area of critical need due to issues associated with environmental persistence, widespread occurrence, biological half-life, toxicity, and nearly ubiquitous human and environmental exposure.  Perfluoroalkyl ether acids (PFEAs) are a sub-class of PFAS and include the compounds hexafluoropropylene oxide dimer acid (GenX), Nafion byproduct 2 (NBP2), and perfluromethoxyacetic acid (PFMOAA).  PFEAs are currently used in the production of fluoropolymers following the phase-out of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), presumably due to more favorable fate and toxicity profiles.  However, monitoring studies have detected GenX, NBP2, PFMOAA and others in a wide range of matrices including surface water, drinking water, and/or human serum, along with legacy PFAS such as PFOA and PFOS.  Little published research is available regarding the potential toxicity of the emerging PFEA compounds compared to the legacy PFAS or cumulative effects of exposure to PFAS mixtures.  We hypothesized that exposure to emerging PFEAs during pregnancy would alter maternal and fetal/neonatal lipid and carbohydrate metabolism leading to adverse neonatal effects, similar to other PFAS, and that mixture exposures would produce dose additive effects.  The data from this project will be useful to state, federal, and other regulatory agencies in the development of hazard assessments for GenX, PFMOAA, and NBP2, and efforts to regulate exposure to multiple PFAS.  These studies characterize the toxic effects of oral GenX, PFMOAA, NBP2, and a PFAS mixture exposure during pregnancy to both the mother and the offspring (fetal and newborn) using a laboratory rat model.  We found multiple, severe effects for GenX and NBP2 that were consistent with other PFAS, such as PFOA and PFOS.  Importantly, it appears that NBP2 is only slightly less potent than PFOS; while GenX is slightly more potent than PFOA and PFMOAA is slightly less potent based on the orally administered dose.  Further, combined exposure to multiple PFAS produced dose additive effects.  The data presented here will be highly valuable for regulators to make scientifically based decisions on the potential adverse effects of NBP2 and PFMOAA on human health and informing future toxicity studies of additional PFAS.    

Citation

Conley, J. Neonatal Effects of In Utero Exposure to PFAS. American Diabetes Association 81st Annual Meeting, N/A-Virtual, NC, June 25 - 29, 2021.