Comparative Toxicity of Seven Aqueous Film-Forming Foam to In Vitro Systems and <i>Mus</i>
Andrew East, Allison M. Narizzano, Lindsay A. Holden, Matthew A. Bazar, Meredith Bohannon, Dmitry Pervitsky, Valerie H. Adams, Emily N. Reinke, Michael J. Quinn
Abstract
Abstract The comparative toxicity of six per- and polyfluoroalkyl substance (PFAS)–free and one PFAS-containing aqueous film-forming foam (AFFF) was evaluated in an outbred mouse species as well as several in vitro assays. The in vivo toxicological profile of PFAS-free AFFFs in short-term, high-concentration exposures is different than that of a PFAS-containing AFFF. The PFAS-containing reference product induced increased liver weights, while the PFAS-free AFFFs were linked to either decreased or unaffected relative liver weights. The in vitro toxicological profile across PFAS-free AFFFs was uniform except in the Microtox® assay, where thresholds were variable and spanned several orders of magnitude. This direct comparison of products through short-term toxicity tests and in vitro screenings represents early data to support evaluation of potential regrettable substitutions when selecting alternative PFAS-free AFFFs. Further work in diverse taxa (e.g., aquatic organisms, terrestrial invertebrates, birds) and mammalian studies capturing sensitive life stages will refine and expand this data set across a range of risk-relevant toxicological endpoints. Environ Toxicol Chem 2023;42:2364–2374. Published 2023. This article is a U.S. Government work and is in the public domain in the USA. Abstract CD-1 mice were exposed to six per- and polyfluoroalkyl substance (PFAS)–free aqueous film-forming foam (AFFF) products and one PFAS-containing AFFF product. Relative liver weight in male mice presented a graded response across products and indicates that PFAS-free AFFF products have a different mechanism of toxicity from PFAS-containing AFFF products and that PFAS-free AFFF products show limited effects overall.