Host: The Japanese Society of Toxicology
Name : The 50th Annual Meeting of the Japanese Society of Toxicology
Date : June 19, 2023 - June 21, 2023
Pefluoroalkyl substances (PFASs) are synthetic chemical compounds with at least a perfluorinated methyl group (–CF3) or a perfluorinated methylene group (–CF2–) in the molecule. Approximately 5000 distinct PFASs are known. Those compounds are chemically stable and have been used in variety applications; i.e., Teflon emulsion vehicle, fire-fighting foams, surfactants and cosmetic foundations. Because they are stable in the environment, legacy PFAS, PFOS, PFOA and PFHxS have been registered as persistent organic pollutants (POPs) in the Stockholm Convention. Those three PFASs have very long biological half-lives in human ranging from 2y to 6y years and are not metabolized in the body. There have been several lines of epidemiological evidence that these PFASs impair lipid metabolisms, have immunotoxicity, retard fetal and neonatal growth and increase the risk of renal cell cancer. In my presentation, I would like to discuss the environmental problems in Japan and basic toxicology of legacy PFASs, PFOS and PFOA mainly based on our data. As for the basic toxicology information, I would like to show 1) the enterohepatic circulation of PFOS and PFOA, by which their biological half-lives are extended, 2) modification of hepatic toxicity by PPARα (peroxisome proliferator activated receptor alpha), 3) a candidate transporter and 4) the effects on Na and Ca channels. In closing, I would like to address importance of providing mechanistic insights in transporters, immunotoxicology and carcinogenesis to support epidemiological studies.
