Building Collision Fatalities for Monitoring Per- and Polyfluorinated Alkyl Substances (PFAS) in Wild Bird Populations

Ecosystem exposures and effects of per- and polyfluoroalkyl substances (PFAS) are poorly understood. Field studies reveal that birds bioaccumulate PFAS through ecosystem exposures. However, drivers of PFAS exposures are poorly understood and may suffer from species and geographic biases due to the significant effort and cost of conducting field studies for measuring PFAS in wild birds. Therefore, alternative methods for assessing avian PFAS exposures are needed. Herein, we explore the utility of opportunistic sampling of building collision fatalities for expanding knowledge of PFAS exposures in wild birds. Concentrations of 40 PFAS of regulatory concern were measured in 50 livers from eight passerine species killed in building strikes during their migration through Chicago, IL. Results indicate that exposure is dominated by perfluoroalkyl carboxylic acids, fluorotelomer carboxylic acids, and perfluoroalkyl sulfonic acids and that physiological factors and feeding strategies may impact PFAS exposures. Comparing liver concentrations to those found in similar species at contaminated and noncontaminated sites indicates that PFAS levels detected in building collision fatalities are representative of levels found in wild populations, suggesting that this approach may circumvent challenges encountered in traditional bird biomonitoring studies and offer opportunities for more detailed study of factors governing PFAS exposure and bioaccumulation.