Presenter: Adam Lachapelle

Faculty Sponsor: Alicia Timme-Laragy

School: UMass Amherst

Research Area: Public Health and Epidemiology

Session: Poster Session 5, 3:15 PM - 4:00 PM, Auditorium, A24

ABSTRACT

Aqueous film forming foams (AFFF) are firefighting foams used at military bases and firefighter training facilities and are a major source of environmental per-and-polyfluoroalkyl substance (PFAS) contamination. Due to their persistence, PFAS remain in the environment and pose ongoing risks for exposure. While the toxicity of many individual PFAS have been reported, the toxicity of PFAS mixtures are less understood. In this study, we assess the toxicity of a 27 PFAS mixture detected in AFFF, in comparison to a mixture of 6 regulated PFAS, using transgenic zebrafish larvae.

Both PFAS mixtures were synthesized by the Massachusetts Pesticide Analysis Lab. Homozygous Nrf2a wildtype and mutant (nrf2a^fh318-) Tg(ins:GFP) embryos were exposed to either mixture at a low, medium, or high concentration, with 0.1% methanol as a solvent control from 3-100 hours post fertilization (hpf). Larvae were imaged under brightfield and fluorescence microscopy to quantify fish length, yolk sac area, pericardial area, and islet area.

Our results show that fish length, islet area, yolk sac area, and pericardial area were significantly altered by exposure to the 27 PFAS mixture. Fish length was more sensitive and the effect on islet area appears to be less severe in mutant larvae. Exposure to the 6 PFAS mixture altered fish length in both genotypes and yolk sac area in wildtype.

We identify that the 27 PFAS mixture is more toxic than the 6 PFAS mixture, and the Nrf2 pathway potentially modulates both mixtures toxicity. This indicates that current regulations are insufficient to predict environmental PFAS toxicity.