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The occurrence of per‐ and polyfluoroalkyl substances (PFAS) in wastewater treatment plants (WWTPs) is well recognized. While several studies have examined the occurrence of PFAS in WWTPs, studies assessing the extent to which unit processes impact PFAS phase distribution are relatively lacking. Herein, PFAS enrichment in foams generated during aeration and PFAS accumulation in solids dewatering streams were evaluated in WWTPs. Results of this screening‐level study showed that perfluorooctane sulfonate (PFOS) concentrations were enriched up to three orders of magnitude in foams relative to the aqueous phase. Similarly, total PFAS concentrations in solids dewatering streams were enriched up to 380 times relative to the aqueous influent. The PFAS mass in the dewatering stream was a significant component of the overall PFAS mass exiting the WWTP at one of the facilities examined. Results of this study suggest that there is potential to mitigate PFAS by improved management of these foams and dewatering waste streams. [ABSTRACT FROM AUTHOR]

Long‐chain per‐ and poly‐fluoroalkyl substances (PFAS) have been the active ingredients in firefighting foams for more than 50 years. Due to their extreme persistence, regulatory agencies are concerned about their potential adverse environmental and health impacts. Recently, nonfluorinated chemical constituents have been proposed for use in fire‐fighting foams in an effort to reduce the potential negative impacts of PFAS on terrestrial and aquatic flora and fauna. However, it is important to also determine the potential ecotoxicity of these nonfluorinated foam products, because we have little toxicological information for many of them. In preparation for a chronic study, we conducted an acute (24‐h) oral toxicity test in northern bobwhite quail (Colinus virginianus) using six different fluorine‐free foams; five were commercial foams (BioEx ECOPOL A, Fomtec Enviro USP, National Foam Avio Green KHC, National Foam NFD 20‐391, and Solberg Re‐Healing Foam), and one was an experimental foam (NRL 502W). A short‐chain PFAS‐based foam (Buckeye Platinum Plus C6) was also evaluated for comparative purposes. Groups of five birds were initially pseudogavaged with a volume of each product corresponding to a "limit" (the highest exposure concentration expected to occur environmentally). Only one bird (1 of 35) died during the limit test, indicating that all seven products have an acute median lethal dose in adult quail at or above the limit (~1500 mg/kg body wt). Environ Toxicol Chem 2022;41:2003–2007. © 2022 SETAC [ABSTRACT FROM AUTHOR]

A Society of Environmental Toxicology and Chemistry (SETAC) Focused Topic Meeting (FTM) on the environmental management of per‐ and polyfluoroalkyl substances (PFAS) convened during August 2019 in Durham, North Carolina (USA). Experts from around the globe were brought together to critically evaluate new and emerging information on PFAS including chemistry, fate, transport, exposure, and toxicity. After plenary presentations, breakout groups were established and tasked to identify and adjudicate via panel discussions overarching conclusions and relevant data gaps. The present review is one in a series and summarizes outcomes of presentations and breakout discussions related to (1) primary sources and pathways in the environment, (2) sorption and transport in porous media, (3) precursor transformation, (4) practical approaches to the assessment of source zones, (5) standard and novel analytical methods with implications for environmental forensics and site management, and (6) classification and grouping from multiple perspectives. Outcomes illustrate that PFAS classification will continue to be a challenge, and additional pressing needs include increased availability of analytical standards and methods for assessment of PFAS and fate and transport, including precursor transformation. Although the state of the science is sufficient to support a degree of site‐specific and flexible risk management, effective source prioritization tools, predictive fate and transport models, and improved and standardized analytical methods are needed to guide broader policies and best management practices. Environ Toxicol Chem 2021;40:3234–3260. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]