Oral Presentation Society for Freshwater Science 2025 Annual Meeting

Shifts in PFAS concentrations and mixtures in stream-to-riparian food webs (117738)

Jessica E Brandt 1 , Kaitlyn S Campbell 1 , Jeff S Wesner 2 , David M Walters 3 , Ashley M Helton 1 , Craig Stricker 3 , Anthony Provatas 1 , Johanna M Kraus 3
  1. University of Connecticut, CT, United States
  2. University of South Dakota, Vermillion, SD
  3. U.S. Geological Survey, Columbia, MO

PFAS (per- and polyfluoroalkyl substances) contamination is becoming an increasingly widespread and well-known problem for water resources globally. Following PFAS release to surface waters, food web-mediated processes influence PFAS distribution and the concentrations and compound mixtures that reach species and habitats of concern. Here, we investigated how PFAS concentrations and mixture compositions change with bioaccumulation, metamorphosis, and trophic transfer through stream food webs and into adjacent riparian habitats. We sampled and determined PFAS concentrations in water, sediment, biofilm, seston, detritus, larval and adult aquatic insects, and riparian spiders from five streams in the Farmington River Watershed (CT, USA) between 2022-2023. We first used these data to quantify compound- and site-specific bioaccumulation, trophic, and metamorphic transfer factors. We subsequently developed an ecological model integrating results across streams to build an ecosystem scale understanding of how PFAS concentrations and mixtures shift from aquatic to riparian compartments. This presentation will emphasize the results of the ecosystem scale model to identify compound-specific dietary enrichment patterns, shifts in mixture compositions among compartments, and variation in sum PFAS concentrations from surface water to insects.