Predictors of Serum Per- and Polyfluoroalkyl Substances (PFAS) Levels Among US Career Firefighters

OBJECTIVE: To identify potential predictors of serum concentrations of per- and polyfluoroalkyl substances (PFAS) among a cohort of US firefighters. METHODS: Serum PFAS concentrations were measured in 2056 US structural firefighters between July 2023 and October 2024. Data on demographics, lifestyle behaviors, occupational exposures, and fire agency policies were collected through individual and fire agency surveys and evaluated for associations with serum PFAS concentrations. RESULTS: Plasma and/or blood donation, drinking water source, military service, post-fire on-scene decontamination, turnout gear storage and transportation, rank, using aqueous film-forming foam, and carpet in fire station living quarters were all significant predictors of at least one PFAS chemical ( P ≤ 0.05). CONCLUSIONS: Both individual and departmental predictors of serum PFAS concentrations were identified. These findings can help guide the selection of PFAS exposure reduction activities by firefighters.