Screening potential reproductive and developmental effects of PFAS-free vs. PFAS-containing fire extinguishing agents in mice.

The combined repeated-dose and reproductive/developmental toxicity of six fire extinguishing agents were evaluated in mice: one legacy per- and polyfluoroalkyl substances (PFAS)-containing product and five PFAS-free products. For each product, up to 1,000 mg/kg-d was administered via oral gavage (n = 12/sex/group) before mating, for at least 42 days in males, and through gestation and lactation in females. First filial (F1) generation animals were exposed in utero and via lactation, and directly via oral gavage from postnatal day (PND) 22-42. No animals exhibited statistically significant reductions in reproductive function or pregnancy. Body weights of dams, litters, and weanlings were often decreased by high doses of fire extinguishing agents. The lowest concentration that impacted body weights was 320 mg/kg-d in a PFAS-free product. Perturbations to serum thyroid hormones (both generations) and immunoglobulin levels (F1) were rarely detected. Some hematological changes (e.g., red blood cell parameters) were also detected across the products. Results from these whole-product toxicity tests are consistent with studies of well-characterized ingredients of the products, which are also common ingredients of many household and consumer products. In conclusion, PFAS-free products were not linked to any of the reproductive or developmental effects commonly seen with individual PFAS exposures at the occupationally relevant concentrations tested. Of the products tested, there was only one PFAS-free fire extinguishing agent that was more toxic than the PFAS-containing product.