PFAS and Precursor Bioaccumulation in Freshwater Recreational Fish: Implications for Fish Advisories

Per- and polyfluoroalkyl substances (PFAS) are a diverse
class
of fluorinated anthropogenic chemicals that include perfluoroalkyl
acids (PFAA), which are widely used in modern commerce. Many products
and environmental samples contain abundant precursors that can degrade
into terminal PFAA associated with adverse health effects. Fish consumption
is an important dietary exposure source for PFAS that bioaccumulate
in food webs. However, little is known about bioaccumulation of PFAA
precursors. Here, we identify and quantify PFAS in recreational fish
species collected from surface waters across New Hampshire, US, using
a toolbox of analytical methods. Targeted analysis of paired water
and tissue samples suggests that many precursors below detection in
water have a higher bioaccumulation potential than their terminal
PFAA. Perfluorobutane sulfonamide (FBSA), a short-chain precursor
produced by electrochemical fluorination, was detected in all fish
samples analyzed for this compound. The total oxidizable precursor
assay interpreted using Bayesian inference revealed fish muscle tissue
contained additional, short-chain precursors in high concentration
samples. Suspect screening analysis indicated these were perfluoroalkyl
sulfonamide precursors with three and five perfluorinated carbons.
Fish consumption advisories are primarily being developed for perfluorooctane
sulfonate (PFOS), but this work reinforces the need for risk evaluations
to consider additional bioaccumulative PFAS, including perfluoroalkyl
sulfonamide precursors.