Toxicology assessment for six per- and polyfluoroalkyl (PFAS)-free aqueous film forming foam (AFFF) products.

Abstract

There is an urgent need to understand the toxicity hazards of aqueous film forming foam (AFFF) replacement products to ensure the balance between performance and toxicity hazards and avoid regrettable substitutions during the rapid phasing out of per- and polyfluoroalkyl substance (PFAS)-containing AFFFs. To address this need, we assessed the toxicity of six candidate PFAS-free products via literature review, estimation techniques, and incorporation of testing data from whole products and compared them against one PFAS-containing product. Then, we combined the relative hazards across human occupational exposure (e.g., concentrate, foam, or dilute exposures), human environmental exposure (e.g., training, emergency response, cleanup), and environmental exposure to aquatic, mammalian, and other terrestrial species using an index-based scoring system to quantify potential hazards across these domains. We found that most PFAS-free products in their concentrated form may cause dermal and ocular irritation, and aquatic toxicity may be a concern from direct or repeated environmental releases. Additionally, all PFAS-free AFFF products assessed contain chemicals that are notable as plausible hazards resulting from release uncertainties (e.g., concentration, release volume, release timing), but the PFAS-free AFFF products appear to have a lower likelihood of environmental persistence and bioaccumulation and to have lower oral human health toxicity than the PFAS-containing reference product. Decision makers can use this information alongside cost-benefit, sustainability, or life-cycle analyses to make a data-driven decision for the adoption of PFAS-free AFFF. Integr Environ Assess Manag 2023;19:1609-1618. © 2023 SETAC.