







Abstract. Hundreds of sites across the United States have high concentrations of perfluoroalkyl sulfonamides (FASA), but little is known about their propen
Addressing Urgent Questions for PFAS in the 21st Century
Abstract. Despite decades of research on per- and polyfluoroalkyl substances (PFAS), fundamental obstacles remain to addressing worldwide contamination by

Stability of Per- and Polyfluoroalkyl Substances in Solvents Relevant to Environmental and Toxicological Analysis
Abstract. Per- and polyfluoroalkyl substances (PFASs) are widely used anthropogenic chemicals. For environmental and toxicological analysis, it is importan

Development and Evaluation of Aquatic and Terrestrial Food Web Bioaccumulation Models for Per- and Polyfluoroalkyl Substances
Abstract. There is a need for reliable models to predict the food web bioaccumulation and assess ecological and human health risks of per- and polyfluoroal

Perfluorinated Carbon Chain Length Drives Uptake of Diverse Per- and Polyfluoroalkyl Substances in Field-Deployed Passive Samplers
Abstract. Per- and polyfluoroalkyl substances (PFAS) are a group of compounds of high concern due to their ubiquity, persistence, and adverse health impact

Characterizing the Areal Extent of PFAS Contamination in Fish Species Downgradient of AFFF Source Zones
Dataset of targeted PFAS and extractable organofluorine concentrations in water, sediment, and biological tissue samples that support data included in two papers: "Characterizing the Areal Extent of PFAS Contamination in Fish Species Downgradient of AFFF Source Zones" and "Bioaccumulation of Perfluoroalkyl Sulfonamides (FASA)"
Liver and Intestinal Fatty Acid Binding Proteins Are Not Critical for Perfluorooctanesulfonate (PFOS) Tissue Distribution and Elimination in Mice
Abstract. Perfluorooctanesulfonate (PFOS) is a persistent environmental pollutant in the per- and polyfluoroalkyl substances (PFAS) class, known to accumul

Scientific Basis for Managing PFAS as a Chemical Class
Abstract This commentary presents a scientific basis for managing as one chemical class the thousands of chemicals known as PFAS (per- and polyfluoroalkyl substances). The class includes perfluoroalkyl acids, perfluoroalkylether acids, and their precursors; fluoropolymers and perfluoropolyethers; and other PFAS. The basis for the class approach is presented in relation to their physicochemical, environmental, and toxicological properties. Specifically, the high persistence, accumulation potential, and/or hazards (known and potential) of PFAS studied to date warrant treating all PFAS as a single class. Examples are provided of how some PFAS are being regulated and how some businesses are avoiding all PFAS in their products and purchasing decisions. We conclude with options for how governments and industry can apply the class-based approach, emphasizing the importance of eliminating non-essential uses of PFAS, and further developing safer alternatives and methods to remove existing PFAS from the environment.

PFAS and Precursor Bioaccumulation in Freshwater Recreational Fish: Implications for Fish Advisories
Abstract. Per- and polyfluoroalkyl substances (PFAS) are a diverse class of fluorinated anthropogenic chemicals that include perfluoroalkyl acids (PFAA), w

Legacy and Novel Per- and Polyfluoroalkyl Substances in Juvenile Seabirds from the U.S. Atlantic Coast
Abstract. Per- and polyfluoroalkyl substances (PFAS) are anthropogenic, globally distributed chemicals. Legacy PFAS, including perfluorooctane sulfonate (P

How Do We Measure Poly- and Perfluoroalkyl Substances (PFASs) at the Surface of Consumer Products?
Abstract. Exposures to poly- and perfluoroalkyl substances (PFASs) have been linked to metabolic disruption, immunotoxicity, and cancer in humans. PFASs ar

Can profiles of poly- and Perfluoroalkyl substances (PFASs) in human serum provide information on major exposure sources?
Humans are exposed to poly- and perfluoroalkyl substances (PFASs) from diverse sources and this has been associated with negative health impacts. Advances in analytical methods have enabled routine detection of more than 15 PFASs in human sera, allowing better profiling of PFAS exposures. The composition of PFASs in human sera reflects the complexity of exposure sources but source identification can be confounded by differences in toxicokinetics affecting uptake, distribution, and elimination. Common PFASs, such as perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS) and their precursors are ubiquitous in multiple exposure sources. However, their composition varies among sources, which may impact associated adverse health effects.

Passive Sampler Derived Profiles and Mass Flows of Perfluorinated Alkyl Substances (PFASs) across the Fram Strait in the North Atlantic
Abstract. Per- and polyfluorinated alkyl substances (PFAS) are a family of pollutants of high concern due to their ubiquity and negative human health impac

Transport of Legacy Perfluoroalkyl Substances and the Replacement Compound HFPO-DA through the Atlantic Gateway to the Arctic Ocean—Is the Arctic a Sink or a Source?
Abstract. The spatial distribution of 29 per- and polyfluoroalkyl substances (PFASs) in seawater was investigated along a sampling transect from Europe to

High organofluorine concentrations in municipal wastewater affect downstream drinking water supplies for millions of Americans
Wastewater receives per- and polyfluoroalkyl substances (PFAS) from diverse consumer and industrial sources, and discharges are known to be a concern for drinking water quality. The PFAS family includes thousands of potential chemical structures containing organofluorine moieties. Exposures to a few well-studied PFAS, mainly perfluoroalkyl acids (PFAA), have been associated with increased risk of many adverse health outcomes, prompting federal drinking water regulations for six compounds in 2024. Here, we find that the six regulated PFAS (mean = 7 to 8%) and 18 measured PFAA (mean = 11 to 21%) make up only a small fraction of the extractable organofluorine (EOF) in influent and effluent from eight large municipal wastewater treatment facilities. Most of the EOF in influent (75%) and effluent (62%) consists of mono- and polyfluorinated pharmaceuticals. The treatment technology and sizes of the treatment facilities in this study are similar to those serving 70% of the US population. Despite advanced treatment technologies, the maximum EOF removal efficiency among facilities in this work was <25%. Extrapolating our measurements to other large facilities across the United States results in a nationwide EOF discharge estimate of 1.0 to 2.8 million moles F y −1 . Using a national model that simulates connections between wastewater discharges and downstream drinking water intakes, we estimate that the sources of drinking water for up to 23 million Americans could be contaminated above regulatory thresholds by wastewater-derived PFAS alone. These results emphasize the importance of further curbing ongoing PFAS sources and additional evaluations of the fate and toxicity of fluorinated pharmaceuticals.

Whale Baleen To Monitor Per- and Polyfluoroalkyl Substances (PFAS) in Marine Environments
Abstract. Per- and polyfluoroalkyl substances (PFAS) comprise >10 000 synthetic compounds that are globally distributed and highly persistent but remain

Are Fluoropolymers Really of Low Concern for Human and Environmental Health and Separate from Other PFAS?
Abstract. Fluoropolymers are a group of polymers within the class of per- and polyfluoroalkyl substances (PFAS). The objective of this analysis is to evalu
