Perfluoroalkyl chemicals in neurological health and disease: Human concerns and animal models.

Perfluoroalkyl acids (PFAAs) are man-made organic pollutants that are found ubiquitously in the environment and may impact human health. Here, we review the published literature concerning PFAA impacts on neurobiological, neuroendocrine, and neurobehavioral outcomes. We find that there are many mechanisms through which PFAAs may enter the brain and interact with biochemical endpoints to impact neurological function. These results are supported by epidemiological evidence in humans and experimental evidence in animals that demonstrate numerous and varied PFAA impacts on the nervous system. However, the methods commonly used in animal models of PFAA exposure result in durations of exposure and serum PFAA concentrations in blood that may not appropriately mimic human absorption, distribution, metabolism, and excretion. If animal models lack validity, confidence in mechanistic inferences regarding PFAA exposure and brain function is reduced, limiting these studies' utility. Finally, we end by suggesting some potential impacts of PFAA exposure in human neurological health and disease states whose associations may not readily present themselves in the epidemiological literature.