Patterns in Serum Toxicokinetics in Peromyscus Exposed to Per- and Polyfluoroalkyl Substances

Per- and polyfluoroalkyl substances (PFAS) are compounds manufactured for use in paints, cleaning agents, fire suppressants, nonstick cookware, food containers, and water-resistant products. Concerns about PFAS stem from their ubiquitous presence in the environment, persistence, and variable/uncertain bioaccumulation and toxicity. In the present study, 5 perfluoroalkyl acids and one polyfluoroalkyl substance were administered to white-footed mice (Peromyscus leucopus) to elucidate the kinetics of each chemical over 28 d of exposure. Perfluorooctanoate, perfluorohexane sulfonate (PFHxS), and perfluorobutane sulfonate were administered to male and female mice via drinking water. Perfluorooctane sulfonate, perfluorononanoate, 6:2 fluorotelomer sulfonate, and PFHxS were administered to male and female mice via oral gavage. Blood samples collected after 14 or 21 and 28 d of exposure were analyzed for individual PFAS concentrations via liquid chromatography-tandem mass spectrometry. In general, a plateau in serum concentration in this toxicity test-relevant timeline depended on interactions between 1) the type of PFAS (i.e., perfluoroalkyl sulfonic acids [PFSAs] vs perfluoroalkyl carboxylic acids [PFCAs] vs polyfluorinated), 2) continuous versus bolus dosing, and 3) to a lesser extent, sex. Specifically, PFCAs were detected at higher concentration in females than males, whereas PFSAs were generally detected at similar levels across sex. An exception occurred when PFHxS yielded higher serum levels in males than females through bolus, but not continuous, dosing. Type of PFAS had the largest impact on serum concentrations, whereas sex had the lowest. As such, future work on the toxicokinetics of PFAS in common ecological receptors would be valuable to further explore these patterns. Environ Toxicol Chem 2021;00:1-13. (c) 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.