An overview of the uses of per- and polyfluoroalkyl substances (PFAS)

The characterization and performance of a core-shell structured nanoplatform for fluorescence turn-on sensing and selective removal of perfluorooctane substance

The high dissociation energy of C-F bonds makes the natural degradation and decomposition of PFAS (per- and poly-fluoroalkyl substances) nearly impossible, leaving the PFAS wastes widely dispersed and permanently persisting in the natural environment. Consequently, detection and recognition techniques, as well as treatment technology, are highly desired for perfluorooctane sulfonate (PFOS) pollutants. In this work, we designed a core-shell magnetic-porous composite structure (denoted as Fe3O4@MCM-41/EY) for the sensing, adsorption, and removal of PFOS, using EY:CTAB (0.5 μM:80 μM, EY = Eosin Y, CTAB = cetyltrimethylammonium bromide) as the sensing probe, Fe3O4 nanoparticles as the core, and porous silica MCM-41 as the shell. The composite structure of Fe3O4@MCM-41/EY was confirmed by means of SEM (scanning electron microscope), magnetism, XRD (X-ray diffraction), N2 adsorption/desorption, and TGA (thermal gravimetric analysis). A probe loading level of 28.5 % was determined. The probe showed an emission turn-on effect toward PFOS owing to the viscosity variation of the micelles caused by PFOS. A linear fitting equation was obtained as I/I0 = 1.081 + 0.144 × 106[PFOS], R2 = 0.990, with good sensing selectivity and LOD (limit of detection) of 0.27 μM. In addition, Fe3O4@MCM-41/EY removed PFOS efficiently with an adsorption capacity of 0.126 mg/g. The novelty of this work was the simultaneous sensing, adsorption, and removal of PFOS using a core-shell magnetic-porous composite structure.

Targeted determination of volatile fluoroalkyl pollutants and non-targeted screening for environmental monitoring

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants known for their toxicity, mobility, and bioaccumulation. Efficient sample preparation and analysis of these compounds are critical for environmental monitoring. In this study, a novel analytical methodology is presented, integrating dynamic headspace extraction (DHS) and thermal desorption (TD) with one-dimensional (1D) and two-dimensional (2D) gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) for the quantification of target volatile and semi-volatile PFAS. Such an approach also enables the non-targeted screening of other classes of contaminants in aqueous samples. The method was optimized and validated for nine (semi-)volatile PFAS, including fluorotelomer alcohols (FTOHs), acrylate (FTAc), and alkyl sulfonamides (FOSA, FOSE). Three types of adsorbent materials were evaluated during the enrichment step, among which Tenax TA demonstrated superior recovery and reproducibility. Extraction volumes of 1 L, 2 L, and 5 L were tested, with 1 L providing the most consistent recoveries and reproducibility. The optimized method achieved detection limits as low as 2.17 ng L-1, indicating high sensitivity. In a case study involving water from an industrial site, the enhanced separation and detection capabilities of GC×GC-TOFMS enabled the identification of 115 additional environmentally relevant compounds, including halogen-containing compounds, monoaromatics, and polycyclic aromatic hydrocarbons. This integrated DHS-TD-GC×GC-TOFMS approach provides a robust and suitable analytical solution for targeted PFAS monitoring, combining high sensitivity and selectivity with simultaneous non-targeted analytical capabilities - a particularly advantageous feature for the environmental monitoring of (semi-)volatile chemicals in real samples.

Homologues of PFOA substitutes in a semi-closed bay near source region: contamination status and risk assessments

Laizhou Bay (LZB) is heavily polluted by perfluoroalkyl substances (PFAS), especially perfluorooctanoic acid (PFOA), from the nearby industrial emission. PFOA has been subjected to strict control, leading to the increasing use of PFOA substitutes. However, the present pollution status of PFOA substitutes in the LZB area is unclear. In this study, 14 legacy and 18 emerging perfluoroalkyl substances (PFAS) in surface water and sediment samples from LZB area were investigated. Two homologues of hexafluoropropylene oxide trimer acid (HFPO-TrA (C7 and C8)) were first identified in LZB area. The results revealed that emerging PFAS have overtaken legacy PFAS as the major PFAS contaminants in seawater. Legacy PFAS constituted only ∼13-47 % of the total PFAS concentration (∑PFAS) in the seawater and ∼ 37-68 % of the ∑PFAS in the sediment. PFOA was found to be the major legacy PFAS in both seawater and sediment. Among the emerging PFAS, two series of perfluoropolyether carboxylic acid (PFECA) homologues accounted for 86-97 % of the total emerging PFAS in seawater and 57-96 % of the total emerging PFAS in sediment. The major source of PFAS was point source from the Xiaoqing River for the inner bay area, whereas the outer bay area may receive external input from the Bohai Sea. Although environmental risks were low for legacy PFAS, HFPO homologues as a whole may present high risks in a large area by an optimistic evaluation method. This highlights the urgent research needed for emerging PFAS - especially those PFOA substitutes - in the LZB area.

Embryonic exposure to GenX causes reproductive toxicity by disrupting the formation of the blood-testis barrier in mouse offspring

As a replacement for perfluorooctanoic acid, hexafluoropropylene oxide dimer acid, commercially referred to as "GenX", has attracted significant attention. However, a comprehensive understanding of the reproductive systems of male offspring exposed to GenX is lacking. This study aimed to investigate how embryonic exposure to GenX affects the reproductive development of male offspring and the underlying mechanisms. We administered GenX daily via gavage (2 mg/kg body weight/day) to the mice from day 12.5 of pregnancy until delivery. Our results suggested that embryonic exposure to GenX led to delayed onset of puberty in male offspring, with destruction of the testicular structure, disruption of the blood-testis barrier, decreased serum testosterone levels, decreased sperm count, impaired sperm motility, and increased rates of sperm abnormalities. We investigated the mechanism of blood-testis barrier breakdown in vitro by treating Sertoli cells (TM4) with GenX. GenX exposure caused the accumulation of senescent TM4 cells, decreased their glutathione (GSH) levels, and increased their oxidized glutathione levels. GenX inhibited glutaminase activity in TM4 cells, leading to decreased GSH synthesis, increased intracellular oxidative stress, and subsequent TM4 cell senescence, ultimately compromising the blood-testis barrier. Our findings indicated that embryonic exposure to GenX may cause Sertoli cell senescence by altering glutamine metabolism, disrupting the blood-testis barrier, and resulting in abnormal reproductive development in male offspring.

Analysis of neutral per- and polyfluoroalkyl substances (PFAS) by gas chromatography ‒ high resolution mass spectrometry (GCHRMS)

Most of the studies on per- and polyfluoroalkyl substances (PFAS) to date encompass water soluble and ionic PFAS analyzed by liquid chromatography ̶ mass spectrometry, yet analytical methods and information on the occurrence of neutral PFAS are lacking. To this aim, we developed a new method for analysis of forty neutral PFAS using gas chromatography (GC) ̶ Orbitrap mass spectrometry with electron ionization (EI). Analytes were comprised of 29 fluorotelomer alcohols, 6 fluorotelomer acrylates and methacrylates, 3 perfluoroalkane sulfonamides and 2 perfluoroalkane sulfonamido alcohols. Gas chromatographic separation was developed on two GC phases: a standard non-polar (5 % diphenyl and 95 % dimethyl polysiloxane) and a mid-polar (6 % cyanopropylphenyl, 94 % dimethylpolysiloxane). A custom-made high-resolution mass spectral (HRMS) library was developed and used to evaluate PFAS accuracy of identification. Overall, 85 % of PFAS were correctly identified. A quantitative method was developed and evaluated for sensitivity, linearity, reproducibility, and ion interferences. Method sensitivity varied for different PFAS from 1 to 50 ppb based on the lowest calibrated levels. The developed method was utilized for analysis of PFAS in paper-based food contact materials after developing and evaluating the extraction protocol. Method applicability was demonstrated by analyzing paper-based food packaging samples, where 6:2 fluorotelomer alcohol was detected and measured at levels up to 351 ng/g. The developed GCHRMS method can be utilized for identification and measurement of neutral PFAS in various matrices, including food, dust, food contact materials, textiles and others.

New fluorine-free low surface energy surfactants and surfaces

Modification and control of surface properties, such as surface tension γ at air-liquid (AL) interfaces and surface energy at solid-liquid (SL) surfaces, are at the heart of colloid and interface science. Certain applications require low or very low surface tensions γAL and surface energies γSL, for example and not limited to: microemulsification, aqueous foams for fire-fighting, hydrophobic, superhydrophobic and oleophobic surfaces to control spreading and wetting of aqueous and oily liquids on solids. In many cases low surface tensions/energies can only be obtained by employing perfluoroalkyl substances (PFAS) as surfactant or polymer additives or surface treatments. Although fluorocarbons and polymers have been employed for over 80 years, with many industrial and commercial benefits, it is now recognized that PFAS are very hazardous to the environment and health. Hence, in the coming years it will be necessary to phase out PFAS entirely, however, at present, there are very few viable alternatives available. This article outlines the chemical principles for designing F-free low surface energy (LSE) additives, and also covers the most recent advances in the quest for non-fluorinated surfactants and polymeric surface coatings.

Leaching profile of per- and polyfluoroalkyl substances from selected e-waste components and potential exposure pathways from discarded components

Improper handling and disposal of Waste Electrical and Electronic Equipment (WEEE) containing PFAS can lead to the release of these substances into the environment. In this study, we have collected and characterized PFAS leaching profiles of selected e-waste components, including keyboards, cables, monitor screens, and circuit boards, and discussed potential PFAS exposure routes during e-waste disposal by landfilling and associated environmental and health risks. The e-waste components were disassembled, separated, sorted, shredded, and grounded, and leaching experiments were conducted for 30 days to elucidate the potential release and distribution of PFAS from the e-waste components into the environment. PFAS were extracted by solid phase extraction and analyzed through liquid chromatography-mass spectrometry (LC-MS/MS) in e-waste leachate samples to investigate their occurrence and composition in the different e-waste components. The leachate from the e-waste components had 21 out of the 40 PFAS analyzed, in which the most predominant and abundant were perfluorobutanoic acid, perfluorohexanoic acid, perfluorooctanoic acid, and perfluorooctanesulfonic acid. The cables had the highest sum of PFAS in the leachate with concentrations up to 465 ng/kg. Mobilization of PFAS from e-waste components deposited in landfills through leachate requires proper management practices to protect the environment and public health.

Fate of per- and polyfluoroalkyl substances through commercial composting facilities

Rising concerns about solid waste management globally necessitate the adoption of sustainable practices, particularly in dealing with organic waste, which constitutes a significant portion of municipal solid waste (MSW). Composting is an effective waste management strategy that can reduce both the environmental impact and greenhouse gas emissions of organic wastes, while producing valuable organic material (compost) for soil enhancement. However, the presence of persistent contaminants such as per- and polyfluoroalkyl substances (PFAS) in compost poses environmental and human health risks, challenging the sustainable management of organic wastes. This study investigates the fate of 33 PFAS compounds in two composting systems-windrow and in-vessel-focusing on the transformation and persistence of these compounds through the composting process, with the aim of collecting information which will support the identification of strategies to mitigate PFAS contamination in composting practices. The findings indicate significant reductions in total PFAS concentrations after composting, with reductions of 88.3% and 86.3% in the windrow and in-vessel systems, respectively. Notably, certain PFAS compounds, such as PFBS, appeared after composting, while PFPeA, became undetectable, suggesting potential leaching or transformation. Across both leachate and dust samples, PFAS concentrations were relatively low, with only a few compounds detected in each matrix. The final compost products met Australia's proposed NEMP 3.0 guidelines. However, considering the variation in PFAS content within similar categories of waste (feedstock), compliance with regulatory limits may vary. These results highlight the need for continued research into PFAS behaviour during composting and the development of best practices to mitigate contamination risks.

Alternative plastic materials pose higher chemical hazard and aquatic ecotoxicity than conventional plastics

A comparative ecotoxicological profile was conducted on plastic materials with the same use made of conventional polymers versus alternative, potentially biodegradable polymers, frequently marketed as "bio" with claims of lower ecological impact. The sensitive in vivo sea-urchin embryo test (SET) was used for the ecotoxicological characterization, and non-target chemical analyses using GC-MS for the chemical profiling. Toxicological properties of identified chemicals were compiled from ECHA, and NIH databases using an in-house developed Python tool, and qualitative and semiquantitative Chemical Hazard Indices (CHI) were calculated for each material. The alternative materials exhibited on average 2- to 3-fold higher CHI values compared to conventional materials. All PE items, including recycled and oxodegradable samples, lacked any in vivo ecotoxicity, whereas all compostable items showed a certain degree of in vivo toxicity except for the PLA cups. The top six materials containing the highest concentrations of category 1 reproductive toxicity phthalates were all alternative plastics: the recycled bag, compostable knives, PHB resin, and both home-compostable trash sacs. Therefore, while degradable plastics may contribute to reduce the environmental persistence of plastic items, they do not necessarily reduce their ecotoxicological impact, and may increase their chemical hazard.

Occurrence and distribution of per- and polyfluoroalkyl substances (PFAS) in tidal salt marsh creeks

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous global contaminants where the ocean plays a critical role in global PFAS cycling. Large estuarine systems are conduits for anthropogenic contaminants, but little is known regarding PFAS in small tidal creek systems. Surface waters from seven tidal creeks were analyzed for 16 target PFAS including legacy and replacement PFAS. Mean total PFAS ranged from 139.4 to 12,293.8 ng/L in terrestrial influenced upland sampling sites and 33.9-176.3 ng/L in tidal creek mouth sites. Nine PFAS were negatively correlated with salinity and positively correlated with DOC (p < 0.05), indicating that the source of PFAS is predominantly terrestrial. Mean total PFAS of upland sites also had a strong positive relationship with percent impervious surface (R2 = 0.99), indicating the importance of human land use influencing PFAS occurrence. Results of this study will inform future investigations of tidal creeks and their role in PFAS dynamics at the land-sea interface.

Municipal and Industrial Wastewater Treatment Plant Effluent Contributions to Per- and Polyfluoroalkyl Substances in the Potomac River: A Basin-Scale Measuring and Modeling Approach

Managing per- and polyfluoroalkyl substances (PFAS) in water resources requires a basin-scale approach. Predicted environmental concentrations (PEC) and stream-vulnerability scores for PFAS were determined for the Potomac River watershed in the eastern United States. Approximately 15% of stream reaches contained municipal and/or industrial wastewater treatment plant (WWTP) discharges that are presumptive PFAS sources, comprising from <1 to >90% of streamflow. Mean annual PEC, based on the summed concentrations of eight PFAS detected in WWTP effluents (ΣPFASPEC), for all stream reaches in the watershed was 3.8 ng L-1, and stream reaches impacted by WWTP had perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) PEC of 0.39 and 0.14 ng L-1. For locations where measured-environmental concentrations (MEC) were determined, municipal and industrial WWTP contributed 7.8% (0 to 65%) of the total annual streamflow and MEC were greater than PEC in 99% of the samples, indicating additional potential PFAS sources. The mean ΣPFASPEC was 9.1 ng L-1 compared to a mean sum of PFAS MEC of 34 ng L-1. Under mean-August low-flow, 17% and 9.4% of the water-supply intakes had maximum PFOA and PFOS PEC exceeding drinking water maximum contaminant levels.

Nontarget Screening and Occurrence of Emerging Per- and Polyfluoroalkyl Substances in Municipal and Semiconductor Industrial Wastewater: A Large-Scale Survey in China

Due to the lack of transparency in the production and applications of emerging per- and polyfluoroalkyl substances (PFAS), it is a huge challenge to grasp the real PFAS pollution profile in a specific region or industry by target analysis. This study collected extensive samples across China, including municipal wastewater from 9 major cities and wastewater from various manufacturing stages at 3 large semiconductor factories. Suspect and nontarget screening were conducted along with target analysis, and 82 PFAS in 25 classes were identified. Notably, this is the first study to investigate PFAS contamination in semiconductor wastewater on the Chinese mainland. Moreover, 13 classes of PFAS were reported for the first time worldwide in semiconductor wastewater, including multiple hydrosubstituted perfluoroalkyl carboxylic acid (mH-PFCA), ether-inserted PFCA (OPFCA), and perfluoroalkyl alcohol (PA) derivatives. The highest total concentrations of target, suspect, and nontarget PFAS in semiconductor wastewater (12 μg/L) were substantially higher than those measured in all municipal wastewater (25-950 ng/L). The composition of PFAS varied regionally in semiconductor wastewater. Total oxidizable precursor assay revealed the presence of unknown precursors (0.043-0.83 nmol/L), which cannot be directly monitored but may pose a greater PFAS contamination risk in semiconductor water treatment and discharge processes.

Prenatal PFAS exposure associates with DXA assessed markers of adiposity in 7-year-old children from the Odense Child Cohort

The global increase in childhood overweight and obesity presents significant public health concerns due to its long-term health implications. Emerging evidence suggests that exposure to endocrine disrupting chemicals, such as per- and polyfluoroalkylated substances (PFAS), may be obesogenic and contribute to adiposity. This study aimed to investigate the association between prenatal PFAS exposure and markers of adiposity in 7-year-old children, focusing on potential sex-specific differences. Data was analyzed from 881 mother-child pairs in the Odense Child Cohort, Denmark. Maternal serum concentrations of perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) were measured in early pregnancy. At age 7, body composition, including body mass index (BMI), lean mass and fat distribution (total, gynoid, and android), was assessed using dual-energy X-ray absorptiometry (DXA). The median (25th;75th percentile) concentrations of PFHxS, PFOS, PFOA, PFNA, and PFDA were 0.4 (0.2;0.5), 7.6 (5.6;10.4), 1.7 (1.1;2.3), 0.6 (0.5;0.8), and 0.3 (0.2;0.4) ng/mL, respectively. Multiple linear regressions were used to assess sex specific associations between maternal PFAS concentrations and markers of adiposity. In girls, 1 ng/mL increase in maternal PFOA was associated with 2.0 % (95 % confidence interval: 0.3; 3.7) increase in total fat, 1.3 % (-0.3; 2.9) increase in gynoid fat, and 3.8 % (0.6; 7.0) increase in android fat. Associations for PFNA and PFDA followed similar trends, whereas higher maternal PFOS concentrations were associated with lower BMI among both girls and boys. These findings suggest that prenatal exposure to certain PFAS may influence the accumulation of excess fat in girls. Our findings highlight the importance of studying sex specific differences and using accurate measures of body composition as BMI may not adequately reflect body fat in children during growth.

Predicting peroxisome proliferator-activated receptor gamma potency of small molecules: a synergistic consensus model and deep learning binding affinity approach powered by Enalos Cloud Platform

Peroxisome proliferator-activated receptor gamma (PPARγ) antagonists play a critical role in regulating glucose and lipid metabolism, making them promising candidates for antidiabetic therapies. To support the ongoing search of such compounds, this study introduces two advanced in silico models for predicting the binding affinity and biological activity of small molecules targeting PPARγ. A neural network was developed to classify compounds as strong or weak binders based on molecular docking scores. Additionally, a consensus model combining Random Forest, Support Vector Machine, and k-Nearest Neighbours algorithms was implemented to predict the antagonistic activity of small molecules. Both models were rigorously validated according to the Organisation for Economic Co-operation and Development (OECD) guidelines, to ensure generalisability and sufficient efficiency in detecting the minority class (active antagonists). Mechanistic insights into how key molecular descriptors influence PPARγ activity were discussed in a posteriori interpretation. A case study involving 34 prioritised per- and polyfluoroalkyl substances (PFAS) were screened with the developed workflows to demonstrate their practical application. The models, integrated into user-friendly web applications via the Enalos Cloud Platform, enable accessible and efficient virtual screening, supporting the discovery of PPARγ modulators.

Perfluoroalkane Sulfonamides and Derivatives, a Different Class of PFAS: Sorption and Microbial Biotransformation Insights

Perfluoroalkane sulfonamides and their derivatives (FASAs), an emerging subclass of per- and polyfluoroalkyl substances (PFAS), have attracted increasing attention due to their widespread applications, environmental persistence, and potential biological toxicity. Unlike perfluoroalkyl acids (PFAAs), FASAs can be transformed by microorganisms in the environment, producing fluorinated intermediates that eventually form stable PFAAs. A key difference of FASAs is that their pKas enable them to exist as neutral species or zwitterions, unlike all other PFAS subclasses, which are all anions. Sorption processes regulate the bioavailability of FASAs to microorganisms for transformation, driving the environmental transport and fate of FASAs. In this critical review, we provide a comprehensive overview of the classification, properties, and environmental fate of FASAs, with a focus on sorption and microbial transformation. We discuss recent advancements in understanding the sorption of FASAs onto soil, sediment, and microbial biomass, including key sorption descriptors and influencing factors. Additionally, we examine the microbial biotransformation of FASAs, detailing transformation pathways, key intermediates, transformation kinetics, and enzymes involved. Finally, we identify critical research gaps and propose future directions to advance the study of the sorption and biotransformation of FASAs in environmental systems. Mechanistic understanding of these processes is crucial for managing sites impacted with FASAs.

Integration of Animal, Population, and Toxicogenomic Evidence on the Hematotoxic and Immunosuppressive Effects of Environmental Exposure to PFAS Mixtures in Adolescents

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are emerging contaminants widely found in drinking water and food, potentially entering the human body through these sources. To investigate these effects, we simulated PFAS exposure doses in animal models, ranging from general population to occupational levels, and analyzed blood and spleen samples. Epidemiological studies linked PFAS exposure to immunosuppression and hematotoxicity, while toxicogenomic analyses validated the underlying biological mechanisms. PFAS exposure caused immunotoxic effects, including altered blood parameters and lymphocyte edema. Cellular abnormalities such as decreased cytoplasmic density, incomplete rough endoplasmic reticulum, chromatin condensation, lymphocyte nuclear shrinkage, and reduced mitochondrial cristae were observed. Epidemiological evidence revealed a dose-response relationship between mixed PFAS exposure and hematologic indices such as hematocrit (HCT), hemoglobin (HGB), platelet count (PLT), platelet-to-lymphocyte ratio (PLR), white blood cell count (WBC), monocyte percentage, and platelet large cell ratio (PLCR), with perfluorooctanoic acid (PFOA) playing a dominant role. Toxicogenomic analysis identified genes associated with platelets, anemia, and leukocyte function, linked to inflammation, Th17 cell differentiation, apoptosis, lipid metabolism, atherosclerosis, and JAK-STAT signaling. This study provides novel insights into the hematotoxicity and immunosuppressive effects of mixed PFAS exposure, emphasizing the need for PFAS substitution, removal, and policies addressing mixed exposures to protect public health.

Innovative Biobased Thermoplastic Binders for Sustainable Lithium-Ion Batteries

The growing global demand for batteries has driven the search for sustainable materials for energy storage applications. One promising approach to enhance the sustainability of lithium-ion batteries (LIBs) is replacing poly-(vinylidene fluoride) (PVDF) with biobased polymers as binders. However, the primary challenge lies in identifying biobased binders that can meet the mechanical and electrochemical performance requirements necessary for high-efficiency batteries. Balancing sustainability with performance remains an obstacle in the development of biobased alternatives. This study explores the potential of novel biobased polymers to replace PVDF as a binder in LFP cathodes. Biobased polymers, synthesized from isosorbide and poly-(ethylene glycol) (PEG), were developed, and the results show that cathodes using the ISB-25PEG binder exhibit superior adhesion, cohesion, and battery performance that is comparable to that of the traditional PVDF binder. These findings highlight the potential of ISB-25PEG as a sustainable and high-performance alternative to the next generation of energy storage devices, marking an important step forward in the development of environmentally friendly battery technologies.

Novel and legacy per- and polyfluoroalkyl substances in humans: Long-term temporal variability and metabolic perturbations

As legacy per- and polyfluoroalkyl substances (PFAS) are phased out, numerous substitutes have emerged, raising concerns about their potential health impacts. Using targeted and untargeted approaches, we evaluated plasma PFAS on an -omic scale, examining temporal variability and associated metabolomic disruptions. A total of 400 blood samples from 200 Sister Study participants (collected in 2007-2008 and 2013-2014) were analyzed using liquid chromatography with high-resolution mass spectrometry. Temporal variability was assessed using Spearman correlations and intraclass correlation coefficients. Network analysis, metabolome-wide association studies, and pathway analysis were used to evaluate the impacts of PFAS mixtures on the human metabolome. We detected 24 legacy PFAS via the targeted approach and 1,802 features annotated as potential PFAS via the untargeted approach (21 confirmed by reference standards). While legacy PFAS demonstrated low temporal variability, novel PFAS, especially those that have increased in abundance over time, demonstrated greater temporal variability. The legacy PFAS mixture was associated with lipid and amino acid metabolism, while other PFAS mixtures consisting of novel PFAS affected a wider range of metabolic pathways in addition to amino and lipid metabolism, such as carbohydrate, cofactor and vitamin, and endocrine metabolism. These findings underscore the need for further research on these novel PFAS and their health effects.

Contamination levels and distribution of persistent and non-persistent pollutants in paired hair, urine and serum samples from a Belgian non-occupationally exposed population

Designing ideal human biomonitoring studies involves the selection of reliable markers of exposure in adequate biological matrix. Besides conventional matrices such as blood or urine, hair has been increasingly investigated as a promising noninvasive alternative. However, understanding the pollutant distribution between differing biological compartments is essential for reliable interpretation of data collected. Therefore, the contamination levels and the distribution of some persistent (8 perfluoroalkyl substances - PFAS - and 6 polychlorobiphenyls - PCBs) and non-persistent pollutants (2 bisphenols and 3 parabens) were investigated in paired serum and hair samples, or paired spot urine and hair samples obtained from 30 Belgian non-occupationally exposed individuals. The levels measured were close to those reported in recent larger-scale studies. PFAS, PCB and bisphenol distributions largely differed depending upon the matrix and within the same chemical family depending upon the congener. The correlation and agreement between pollutant levels in differing matrices demonstrated that the information provided is comparable only for highly chlorinated PCBs and parabens, while the classification of exposure for bisphenols was substantially different according to the matrix. The selection of the human matrix thus remains complex and might markedly bias the results obtained, especially when assessing the health risk related to chemical exposure.

Association of prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances with fetal growth trajectories

BACKGROUND

Maternal perfluoroalkyl and polyfluoroalkyl substances (PFAS) exposure during pregnancy is linked to adverse birth outcomes; however, its impact on fetal growth trajectories remains unclear.

OBJECTIVE

To examine the relationship between prenatal PFAS exposure and fetal growth trajectories.

METHODS

We included 352 mother-infant pairs from a prospective study conducted at Changsha Hospital for Maternal and Child Health Care, Hunan Province, China. Maternal blood samples at 11-13 weeks gestation were analyzed for 25 PFAS. Fetal growth indicators-estimated fetal weight (EFW), biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL)-were measured at 14-41 weeks of gestation and expressed as Z-scores using INTERGROWTH-21st standards. Linear mixed-effects models assessed associations between PFAS levels and growth trajectories, with subgroup analyses performed by infant sex.

RESULTS

Early pregnancy perfluorooctanoic acid (PFOA) concentration was negatively associated with EFW (β = -0.17, 95% confidence interval [CI]: -0.33, -0.01) Z-scores, perfluorodecanoic acid (PFDA) concentration was negatively associated with BPD (β = -0.13, 95% CI: -0.26, -0.002) and AC (β = -0.12 95% CI: -0.23, -0.004) Z-scores; perfluoroundecanoic acid (PFUdA) concentration was negatively associated with EFW (β = -0.14, 95% CI: -0.26, -0.02) and BPD (β = -0.18, 95% CI: -0.30, -0.06) Z-scores, perfluorooctane sulfonic acid (PFOS) concentration was negatively associated with AC (β = -0.13, 95% CI: -0.25, -0.01) Z-scores. In contrast, N-ethylperfluoro-1-octanesulfonamide (N-EtFOSA-M) concentration was positively associated with EFW (β = 0.11, 95% CI: 0.02, 0.19), BPD (β = 0.11, 95% CI: 0.02, 0.20) and FL (β = 0.13, 95% CI: 0.04, 0.22) Z-scores and potassium11-chloroeicosafluoro-3-oxaundecane-I-sulfonate (8:2CI-PFESA) concentration was positively associated with HC (β = 0.08, 95% CI: 0.004, 0.16) Z-scores. Subgroup analyses revealed that PFDA, PFUdA, and perfluorotridecanoic acid (PFTrDA) concentrations were negatively associated with EFW Z-scores in female infants, and 8:2CI-PFESA concentrations was positively associated with HC and FL Z-scores in male infants.

CONCLUSION

Legacy PFAS exposure may impede fetal growth, especially in female infants; whereas, novel PFAS may be positively associated with fetal growth, particularly in male infants.

Estimation of species- and sex-specific PFAS pharmacokinetics in mice, rats, and non-human primates using a Bayesian hierarchical methodology

The carbon chain length, degree of fluorination, and functional group of per- and polyfluoroalkyl substances (PFAS) influences the bioaccumulation and half-lives of these substances in humans and laboratory animals. Pharmacokinetic (PK) studies using laboratory animals characterize the absorption, distribution, metabolism, and excretion (ADME) of a PFAS and can provide the underlying data for inter-species extrapolation to inform human pharmacokinetics. However, variations in ADME arise due to differences in protein binding and renal and hepatobiliary clearance mechanisms. In particular, sex- and species-specific differences in active transporter abundance and PFAS binding affinity challenge body weight-based extrapolation assumptions from animal models to human PK parameters. Because these protein-dependent changes in ADME do not always scale with species body weight, classic allometric scaling assumptions can fail to account for species-specific transporter-mediated clearance. In addition, study-dependent differences in pharmacokinetic modeling approaches and parameterization techniques can result in large differences among the PK parameters reported in the literature. To better quantify PFAS pharmacokinetics and characterize the underlying uncertainty, we implemented a Bayesian inference hierarchical model to estimate PFAS PK parameters for multiple species (mice, rats, and non-human primates) using numerous single-dose animal studies. Through an alternative parameterization of the one- and two-compartment models, this method improved parameter identifiability and allowed for the use of prior information on PFAS absorption rate, clearance, and volume of distribution. Using reported time-course concentration data, we estimated sex-specific clearance, volume of distribution, and half-life across mice, rats, and non-human primates using a consistent modeling methodology for eight PFAS: PFHxA, PFHxS, PFNA, PFDA, PFBS, PFBA, PFOA, and PFOS. The resulting comparison to available human data demonstrated that standard volume of distribution body-mass scaling (BW1) for PFAS generally agrees with reported human values while standard assumptions for allometric scaling of clearance (BW3/4) are not appropriate for most of the PFAS investigated in this study. In addition, we demonstrated that there may be considerable differences in clearance for PFAS in some species when comparing across different sexes and routes of exposure.

NAM-based analysis of contaminant short-term organ toxicity in HepaRG and RPTEC/TERT1 cells

New Approach Methodologies (NAMs), including cell culture and multi-level omics analyses, are promising alternatives to animal testing. To become useable for risk assessment purposes, they have to be applicable for different substance groups. One important group of substances is food contaminants, including synthetic chemicals, such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), and natural compounds, such as mycotoxins and pyrrolizidine alkaloids. We tested five known contaminants affecting the liver and/or the kidney - PFOS, PFOA, Aflatoxin B1 (AB1), lasiocarpine (Las), and cadmium chloride - using HepaRG and RPTEC/TERT1 cells at non-cytotoxic concentrations for 36 and 72 h. Our NAM-based testing protocol included marker protein analysis for cellular functions and targeted transcriptomics followed by bioinformatics pathway analysis. The effects observed were compared with established in vivo results. Protein analysis indicated various affected pathways in HepaRG cells, with generally fewer effects in RPTEC/TERT1 cells. The strongest transcriptional impact was noted for Las in HepaRG cells. This study demonstrated the test protocol's applicability across different substances, revealing significant differences between HepaRG and RPTEC/TERT1 cell lines. RPTEC/TERT1 cells, while expressing renal-specific CYP enzymes, were less suitable for detecting effects of substances requiring hepatic metabolic activation, like Las and AB1. Our data supports the concept of specific pathway toxicity, with pathway analysis enabling the prediction of effects based on mechanism rather than target organ. Employing multiple omics techniques provided comprehensive insights into various compound effects, including steatosis, reactive oxygen species production and DNA damage, highlighting the potential of an extended omics approach for advancing toxicological assessments.

Association Between Serum Levels of Perfluoroalkyl and Polyfluoroalkyl Substances and Dental Floss Use: The Double-Edged Sword of Dental Floss Use-A Cross-Sectional Study

BACKGROUND

Although evidence suggests that dental floss contains perfluoroalkyl and polyfluoroalkyl substances (PFASs), it is still uncertain whether the use of dental floss contributes to an increased risk of PFAS exposure.

METHODS

We analysed data on serum PFAS concentrations and dental floss usage in a cohort of 6750 adults who participated in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2020. In our study, we used logistic regression, a survey-weighted linear model, item response theory (IRT) scores, inverse probability weights (IPWs) and sensitivity analysis to assess the potential impact of dental floss usage on human serum PFAS levels.

RESULTS

The analysis of six PFASs revealed that dental floss users had higher serum concentrations of perfluorooctanoic acid (PFOA) compared with non-users, while serum concentrations of other PFASs were lower. Dental floss users recorded a lower level of overall PFAS burden score compared with non-users. Sensitivity analysis showed a statistically significant increase in serum PFOA concentration among dental floss users.

CONCLUSION

Our findings suggest that the use of dental floss may be associated differently with serum concentrations of specific PFASs. Among a large representative sample of U.S. adults, individuals reporting the use of dental floss had lower levels of serum PFASs overall, with the exception of PFOA, which was slightly elevated. Dental floss is an important oral hygiene tool, and further research is needed to clarify its role in PFAS exposure.

Dermal permeation of perfluoroalkyl substances in human skin - An in-vitro study

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous, persistent environmental contaminants, posing significant health risks to animals and humans. While dermal exposure to PFAS through daily contact with consumer products such as school uniforms and personal care items is common, the mechanisms and extent of skin uptake remain poorly understood. This study investigated the dermal penetration of 30 PFAS, both as mixtures and individual compounds, using in vitro human skin models in a Franz Diffusion Cell system. Results showed that in a mixture, short-chain PFAS, including FBSA, PFBA, PFPrS, and PFPeA, demonstrated permeation rates of 4.8 ± 2.5 %, 3.7 ± 0.3 %, 2.0 ± 0.1 %, and 1.1 ± 0.1 %, respectively, over 24 h. In contrast, none of the long-chain PFAS penetrated the skin in the same period. When tested individually in water, FBSA exhibited the highest permeation, achieving 7.0 ± 0.9 % (p < 0.05), underscoring its ability to cross the stratum corneum under simulated environmental conditions. These findings highlight that while permeation of long-chain PFAS could be slowed down by the skin barrier, certain short-chain PFAS, such as FBSA, can penetrate human skin in vitro. This study provides crucial preliminary data on PFAS dermal absorption, emphasizing the need for standardized experimental conditions that account for the chemical properties of PFAS and the physiological properties of human skin. Our findings suggest that further research is needed to elucidate the mechanisms of PFAS dermal absorption and better assess the risk of dermal exposure to PFAS.

Competitive adsorption and diffusion of methane and vapor-phase per- and polyfluoroalkyl substances in montmorillonite nano pores: Environmental implications

Vapor-phase perfluoroalkyl and polyfluoroalkyl substances (PFASs), along with methane emissions from landfills has been key contributors of their atmospheric transport and global distribution. Given the persistence, bioaccumulation, and potential health risks associated with PFAS, understanding their transport behavior in landfill gas barrier is of paramount importance. To gain a deeper understanding of the adsorption and diffusion behavior of vapor-phase PFAS in unsaturated, montmorillonite-rich clay barriers, a molecular dynamics simulation was conducted. A 5-nm montmorillonite nanopore incorporating vapor-phase PFAS (Fluorotelomer alcohol, FTOH), methane, and water molecules was modeled considering the interactions between these species. The results indicate that the presence of methane within the montmorillonite system inhibits the diffusion of both water and FTOH. Additionally, methane competes with FTOH for sorption sites, particularly at low moisture content. At 5 % moisture content, the adsorption density peak of methane is 1.5 times greater than that of FTOH due to stronger van der Waals interactions between methane and montmorillonite. However, as moisture content increases, methane adsorption weakens and becomes more dispersed within the montmorillonite pores. In contrast, FTOH retains a distinct adsorption region at 20 % moisture content, exhibiting a density peak of 0.025 g/cm3 that shifts farther from the montmorillonite surface. At high moisture content, FTOH aggregates due to the hydrophobicity of its C-F tail. These findings provide critical insights into the environmental behavior of volatile PFASs and have important implications for the design and optimization of landfill gas barriers.

Mitigating the environmental effects of healthcare: the role of the endocrinologist

Human health depends on planetary health, and yet healthcare provision can have unintended consequences for the health of the planet. Emissions from the healthcare sector include greenhouse gases, air pollution and plastic pollution, alongside chemical contamination. Chemical pollution resulting in endocrine disruption has been associated with plastics, which are a source of concerning additives such as phthalates, bisphenols, perfluoroalkyl and polyfluoroalkyl substances, and flame retardants (all routinely found in healthcare products). Many endocrine-disrupting chemicals are persistent and ubiquitous in the environment (including water and food sources), with potential secondary harms for human health, including disrupting reproductive, metabolic and thyroid function. Here we review evidence-based strategies for mitigating environmental effects of healthcare delivery. We focus on what endocrinologists can do, including reducing demand for healthcare services through better preventative health, focusing on high-value care and improving sustainability of medical equipment and pharmaceuticals through adopting circular economy principles (including reduce, reuse and, as a last resort, recycle). The specific issue of endocrine-disrupting chemicals might be mitigated through responsible disposal and processing, alongside advocating for the use of alternative materials and replacing additive chemicals with those that have lower toxicity profiles, as well as tighter regulations. We must work to urgently transition to sustainable models of care provision, minimizing negative effects on human and planetary health.

Prenatal PFAS exposures and cardiometabolic health in middle childhood in the MIREC cohort

Studies on prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and cardiometabolic health in childhood have produced inconsistent results. In this study, we evaluated associations between prenatal PFAS exposures, individually and as a mixture, and cardiometabolic outcomes including insulin resistance, beta cell function, blood lipids, blood pressure and central adiposity during middle childhood (7-9 years of age) in a Canadian maternal-child cohort (n = 281). We also explored effect measure modification based on child sex and physical activity. We quantified maternal second trimester plasma concentrations of six PFAS and measured 11 offspring cardiometabolic outcomes at a 7-9-year follow-up. In single-exposure models, ten-fold higher prenatal PFDA (β: -0.82, 95% CI: -1.36, -0.28), PFNA (β: -0.8, 95% CI: -1.41, -0.19), and PFOA (β: -0.69, 95% CI: -1.18, -0.19) concentrations were associated with lower diastolic blood pressure z-scores. This association did not persist when considering PFAS exposures as a mixture using quantile g-computation. Associations between PFAS exposures, individually or as a mixture, and other cardiometabolic outcomes were null. We observed no effect measure modification by child sex or physical activity (p-values for interaction ≥0.2). Our results contradict existing studies that suggest prenatal PFAS exposures are associated with adverse childhood cardiometabolic outcomes. Future studies should consider alternative markers of cardiometabolic health, trajectories in cardiometabolic health throughout childhood, and further explore potentially protective health behaviors.

Evaluating the environmental occurrence of per- and polyfluoroalkyl substances (PFAS) and potential exposure risk for recreational shellfish harvesters in the Great Bay Estuary, New Hampshire

BACKGROUND

Shellfish may be an important contributor to PFAS exposure from seafood consumption. Yet, shellfish consumption patterns are distinct from other seafood varieties and PFAS exposure via shellfish consumption has not been well studied, especially among recreational harvesters who may be exposed to PFAS through direct consumption of shellfish, incidental ingestion of sediment, and dermal absorption.

METHODS

Collocated surface water, sediment, and bivalve shellfish samples were collected in the Great Bay Estuary, a prominent estuary in New Hampshire, USA with multiple known PFAS sources. All media were analyzed for 27 PFAS compounds via UPLC-MS/MS. Human health risk of PFAS exposure from recreational shellfish harvesting was estimated for typical and high seafood consumers across multiple exposure routes using available health guidance values.

RESULTS

PFAS were detected in all Great Bay water, sediment, and shellfish samples. PFAS concentrations varied spatially, and profiles varied by media type, with shorter chain compounds found in water and longer chain compounds found in sediment and shellfish. For adults, PFAS exposure risk from recreational shellfish harvesting was greatest from direct consumption of shellfish (>99 % of estimated daily PFAS dose), followed by dermal absorption and incidental sediment ingestion. For children, dermal absorption and incidental ingestion were also important, contributing up to 10 % of estimated daily exposure. PFAS exposure risk from consuming razor clams exceeded the reference hazard quotient of 1 for multiple compounds among the general population that consumes typical or greater amounts of seafood, and among persons of childbearing age and young children who consume high amounts of seafood.

CONCLUSIONS

High frequency recreational shellfish harvesting and consumption may increase exposure to certain PFAS.

Upcycling of Waste Fluororubber to Photocurable High-Performance Vinyl-Terminated Liquid Fluororubber by Multifield Coupling One-Pot Stepwise Reactions

To address the challenges of recycling and high-value utilization of waste fluororubbers, an effective method is reported for producing novel photocurable vinyl-terminated liquid fluororubbers (VTLF) with elevated fluorine content (63.1%), superior temperature resistance (T10% = 335 °C) from commercial waste fluororubbers. The approach employs a streamlined, multifaceted system (oxidative degradation/condensation reaction) integrating microwave, mechanical, and steady-state temperature fields. This system facilitates both efficient recycling and high-value transformation of waste fluororubbers. Initially, waste fluororubbers undergo controlled/oxidative degradation induced by alkali and hydrogen peroxide to yield carboxyl-terminated liquid fluororubbers (CTLF). Subsequently, condensation reaction system efficiently converts carboxyl groups into photoreactive vinyl groups. Ultimately, environmentally friendly and efficient photocuring of VTLF is achieved. The nonthermal effects of microwave fields reduce the total process time to just 1 h. The resulting photocured VTLF exhibits not only the comprehensive properties of conventional fluororubbers but also excellent chemical stability and unique light transmittance (94.21%). This study proposes a green, straightforward upcycling strategy within the circular economy framework to mitigate environmental issues associated with rubber's covalent crosslinking. Furthermore, it opens avenues for designing and synthesizing novel fluoropolymers for diverse applications.

Exposure to Legacy Per- and Polyfluoroalkyl Substances from Diet and Drinking Water in California Adults, 2018-2020

People are exposed to per- and polyfluoroalkyl substances (PFAS) through multiple sources, with diet historically considered a major source in general populations. This study characterized legacy PFAS in serum from 700 California adults and examined contributions from diet and drinking water. We applied robust regression to estimate associations between nontransformed serum PFAS concentrations, self-reported food consumption, and drinking water PFAS concentrations measured under the USEPA's third Unregulated Contaminant Monitoring Rule (2013-2015). Detectable drinking water concentrations were associated with increased serum perfluorooctanoic acid (PFOA) (0.26 ng/mL; 95% CI: 0.077, 0.43), perfluorohexanesulfonic acid (PFHxS) (0.64 ng/mL; 95% CI: 0.058, 1.23), and perfluorooctanesulfonic acid (PFOS) (0.39 ng/mL; 95% CI: -0.76, 0.86). Seafood consumption was associated with increased perfluorononanoic acid (PFNA) (0.013 ng/mL; 95% CI: 0.0058, 0.021), perfluorodecanoic acid (PFDeA) (0.0059 ng/mL; 95% CI: 0.0026, 0.0092), and perfluoroundecanoic acid (PFUnDA) (0.010 ng/mL; 95% CI: 0.0054, 0.015), while eggs were associated with increased PFDeA (0.0035 ng/mL; 95% CI: 0.00010, 0.0069) and PFNA (0.0073 ng/mL; 95% CI: 0.00017, 0.014). Findings could indicate that dietary contributions may be less than those in earlier studies conducted in other populations, possibly due to shifts in PFAS production over the past 20 years, and that drinking water remains an important source of exposure to PFOA and PFHxS in this population.

Accumulation of per- and polyfluoroalkyl substances (PFAS) in tissues of wild boar (Sus scrofa)

The widespread application of per- and polyfluoroalkyl substances (PFAS) resulted in ubiquitous environmental contamination. Understanding the PFAS tissue distribution in mammals and humans is crucial for the assessment of potential health risks. The levels of eleven PFAS were determined by UPLC-MS/MS in plasma and various tissues of wild boar (n = 82) hunted in Germany. The most prevalent PFAS (PFOA, PFNA, PFHxS and PFOS) were detected in all analyzed samples. The median level of the sum (Σ 4PFAS) was highest in liver (90.2 μg/kg), followed by kidney (9.45 μg/kg), plasma (7.63 μg/L), lung (6.84 μg/kg), heart muscle (2.60 μg/kg), spleen (2.46 μg/kg), and skeletal muscle (1.03 μg/kg). Consumption of a single portion (125 g) of liver containing the Σ 4PFAS median level would result in a 36.6-fold exceedance of the tolerable weekly intake (TWI) of EFSA in a 70 kg-person. The accumulation (calculated as tissue/plasma ratio) of perfluoroalkyl carboxylic acids with ηpfc = 8-13 in lung, spleen, muscle and heart tissues increased with molecule size, indicating passive mechanisms of distribution driven by hydrophobicity. In contrast, liver and kidney distribution coefficients scattered, indicating additional involvement of chain-length dependent active transport processes. The highest accumulation was observed for PFOS in the liver (median tissue/plasma ratio 18.0). The shortest PFAS included in the study (PFHxA, PFHpA, PFOA, PFBS and PFHxS) did not accumulate in any of the tissues, probably due to strong binding to blood proteins like serum albumin and their relative polarity impeding passive membrane diffusion.

Per- and polyfluoroalkyl substances (PFAS): immunotoxicity at the primary sites of exposure

Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic chemicals widely used in industrial and consumer products, leading to environmental contamination and human exposure. This review focuses on perfluoroalkyl acids, a subset of PFAS, which are primarily encountered through diet, including drinking water, and other pathways such as dust ingestion, and dermal contact. Impaired vaccine antibody response has been identified as the most critical effect for risk assessment by the European Food Safety Authority. Furthermore, human epidemiological studies have linked exposure to certain PFAS to various immune-related outcomes, such as asthma, allergies, and inflammatory bowel disease. This review examines potential immunomodulatory effects of perfluoroalkyl acids at the primary sites of exposure: lungs, intestines, and skin, using human epidemiological data as the basis for investigating these impacts. While animal studies are referenced for context, this paper highlights the need for further human-based research to address key questions about PFAS and their immunological impacts. The state of in vitro toxicity testing related to these effects is thoroughly reviewed and critical issues pertaining to this topic are discussed.

Respiratory Health Impacts from Natural Disasters and Other Extreme Weather Events: The Role of Environmental Stressors on Asthma and Allergies

PURPOSE OF REVIEW

The frequency of natural disasters, other extreme weather events, and downstream emissions of emerging contaminants is increasing. One category of health outcome that is now experiencing increased prevalence due to these environmental threats is respiratory disease, specifically asthma and allergies; though a review summarizing current knowledge and research gaps has not been synthesized on this topic in recent years despite growing evidence.

RECENT FINDINGS

We identified recent literature that connects allergy/asthma with environmental events that are increasing in prevalence alongside natural disasters and other extreme weather events, including algal blooms, floods, heat stress, wildfires, and thunderstorms. Coinciding emissions of per-and polyfluoroalkyl substances (PFAS) and microplastics (MPs) are also discussed as downstream outcomes of these environmental events. Available evidence ranged according to environmental event/stressor type, with over 50 papers identified as relevant to this research scope in the last five years. Narrative synthesis of these papers highlighted exposure-disease linkages for stressors related to natural disasters, other extreme weather events, and downstream emissions of emerging contaminants with pulmonary asthma and allergy outcomes. Underlying biological mechanisms are beginning to be elucidated and include widespread inflammation in the lungs and changes in immune cell signaling and function across the pulmonary system. Take home points in this review pave the way for future investigations to better understand the impacts of these environmental events amongst the complex milieu of threats becoming increasingly prevalent worldwide.

Tapwater exposures, residential risk, and mitigation in a PFAS-impacted-groundwater community

Tapwater (TW) safety and sustainability are priorities in the United States. Per/polyfluoroalkyl substance(s) (PFAS) contamination is a growing public-health concern due to prolific use, widespread TW exposures, and mounting human-health concerns. Historically-rural, actively-urbanizing communities that rely on surficial-aquifer private wells incur elevated risks of unrecognized TW exposures, including PFAS, due to limited private-well monitoring and contaminant-source proliferation in urbanizing landscapes. Here, a broad-analytical-scope TW-assessment was conducted in a hydrologically-vulnerable, Mississippi River alluvial-island community, where PFAS contamination of the shallow-alluvial drinking-water aquifer has been documented, but more comprehensive contaminant characterization to inform decision-making is currently lacking. In 2021, we analyzed 510 organics, 34 inorganics, and 3 microbial groups in 11 residential and community locations to assess (1) TW risks beyond recognized PFAS issues, (2) day-to-day and year-to-year risk variability, and (3) suitability of the underlying sandstone aquifer as an alternative source to mitigate TW-PFAS exposures. Seventy-six organics and 25 inorganics were detected. Potential human-health risks of detected TW exposures were explored based on cumulative benchmark-based toxicity quotients (∑TQ). Elevated risks (∑TQ ≥ 1) from organic and inorganic contaminants were observed in all alluvial-aquifer-sourced synoptic samples but not in sandstone-aquifer-sourced samples. Repeated sampling at 3 sites over 52-55 h indicated limited variability in risk over the short-term. Comparable PFAS-specific ∑TQ for spatial-synoptic, short-term (3 days) temporal, and long-term (3 years quarterly) temporal samples indicated that synoptic results provided useful insight into the risks of TW-PFAS exposures at French Island over the long-term. No PFAS detections in sandstone-aquifer-sourced samples over a 3 year period indicated no PFAS-associated risk and supported the sandstone aquifer as an alternative drinking-water source to mitigate community TW-PFAS exposures. This study illustrated the importance of expanded contaminant monitoring of private-well TW, beyond known concerns (in this case, PFAS), to reduce the risks of a range of unrecognized contaminant exposures.

Atmospheric Emission of Per- and Polyfluoroalkyl Substances (PFAS) from a Fluoropolymer Manufacturing Facility: Focus on Emerging PFAS and the Potential Contribution of Condensable PFAS on their Atmospheric Partitioning

Fluoropolymer manufacturing facility (FMF) has been regarded as a main source of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the atmosphere. In this study, suspect screening was performed to identify emerging PFAS in gas, particles, and dust both inside and outside a large FMF in China. A total of 74 emerging PFAS were tentatively identified with a confidence level of 3 or higher, 32 of which were reported in the environment for the first time. The semi-quantitative concentrations of the emerging PFAS, with perfluoroalkyl ether carboxylic acids (PFECAs) and Cl-PFECAs being predominant, accounted for 21-95% (mean: 46%) of the combined concentrations of emerging and legacy PFAS. Although the PFAS concentrations in the atmosphere decreased rapidly by more than 95% within 5 km, short-chain PFAS in PM2.5 were transported farther, especially C4 and C5 perfluoroalkyl carboxylic acids, which decreased by 66% and 79% within 5 km, respectively. Emerging PFAS with an ionic terminal group are mainly distributed in the particle phase, while alcohol-related PFAS are found in the gas phase. The ratios of PFAS in the gas phase inside the FMF were much higher than those outside, which could be reasonably explained by the condensation of gaseous PFAS onto fine particles shortly after being emitted.

Application of a Non-targeted Biomonitoring Method to Characterize Occupational Chemical Exposures of Women Nurses Relative to Office Workers

We analyzed blood serum samples from two unique female occupational cohorts - 60 nurses and 40 office workers in San Francisco, CA - using liquid chromatography and high-resolution mass spectrometry (quadrupole time-of-flight). Applying a nontargeted analysis (NTA) approach, we sought to isolate occupationally related chemical exposures that were unique to nurses by flagging features that were different from office workers in abundance (mean; 95th percentile) or detection frequency. Of 9828 negative electrospray ionization (ESI-) and 6898 positive electrospray ionization (ESI+) detected chemical features, 1094 and 938, respectively, were higher in nurses, possibly due to workplace exposures. We deciphered the molecular structures of these chemical features by applying data-dependent acquisition (DDA) and targeted MS/MS approaches to pooled samples from each occupational group, and we annotated them using spectral MS/MS databases in MS-DIAL. Nurses had higher concentrations of 14 chemicals that we identified at Schymanski Level 1 (N = 6) or 2 (N = 8), as well as 20 tentatively identified chemicals without spectra. Several chemicals may be occupationally relevant for nurses, including a PFAS (6:2 fluorotelomer sulfonic acid), tridecanedioic acid, salicylic acid, and the medications acetaminophen and theophylline. To our knowledge, this study is the first to apply NTA to elucidate novel chemical exposures in nurses.

United States Environmental Protection Agency's Perfluorooctanoic Acid, Perfluorooctane Sulfonic Acid, and Related Per- and Polyfluoroalkyl Substances 2024 Drinking Water Maximum Contaminant Level: Part 2 - Fifteen Misconceptions About the Health Hazards

This paper examines widely held beliefs about the six per- and polyfluoroalkyl substances (PFAS) addressed in the final U.S. Environmental Protection Agency's (EPA) rule on PFAS in drinking water (e.g., the Maximum Contaminant Levels - MCLs). Based on our understanding of the scientific literature and the comments submitted by stakeholders regarding the EPA's regulation that was promulgated in April 2024, we identified 15 misconceptions that had a weak scientific foundation. These are now memoralized in the MCLs for the six PFAS but remain debated due to ongoing ambiguous research findings. Many critics of the MCLs found the EPA's systematic review of the published relevant information, particularly the toxicology of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), to be inadequate. The following seven views are among the most important. First, the EPA asserted that the toxicology of these six chemicals was poorly understood and lacked sufficient data to determine a safe daily intake level for chronic health effects; nonetheless, they promulgated what may be the costliest environmental regulation to date. Notably, adverse effects remain difficult to demonstrate in occupationally exposed individuals even at blood concentrations 50-100 times higher than current background PFAS levels. Second, the Agency indicated that the epidemiology data showed that exposure to PFOA and PFOS caused kidney and potentially other cancers, yet the data were equivocal and do not support that assertion. Third, it was stated that specific non-cancer effects, such as heart disease, would be prevented under the promulgated rule; however, the studies that they relied upon do not show an increased incidence of heart disease even in highly exposed populations. Fourth, the Agency relied on animal data to support its views on the likely toxic effects in humans, despite ample toxicology data that animals, particularly rodents, are poor predictors of the human response to PFAS exposures. Fifth, the EPA predicted a reduction in healthcare expenditures that would offset much of the cost of complying with the MCL, but, they did not have adequate data to support this prediction. Sixth, the EPA suggested that these six PFAS act through a shared mechanism of action (i.e., PPARα pathway induction); however, data indicate that PPARα induction in humans may be 80% less than what is observed in rodents. Also, induction of the PPARα pathway is not a cause of systemic disease. Seventh, the Agency failed to disclose that achieving the new MCL would yield negligible reductions in blood PFAS levels even among highly exposed populations, given drinking water accounts for only 20% or less of total PFAS exposure. The survey that could answer that question, the EPA's fifth Unregulated Contaminant Monitoring Rule, was only 25% complete at the time the MCL was promulgated. Overall, our analysis concluded that while the EPA's intent to regulate these chemicals due to their environmental presence was necessary, the derivation of the MCLs and the alleged health effects was based on the application of the precautionary principle rather than robust scientific evidence.

Predicting Bioconcentration Factors of Per- and Polyfluoroalkyl Substances Using a Directed Message Passing Neural Network with Multimodal Feature Fusion

Amid growing concerns regarding the ecological risks posed by emerging contaminants, per- and polyfluoroalkyl substances (PFASs) present significant challenges for risk assessment due to their structural diversity and the paucity of experimental data on their bioaccumulation. This study investigated the bioconcentration factors (BCFs) of 18 emerging and legacy PFASs using zebrafish in a flow-through exposure system and constructed a robust BCF prediction model to address the data gaps associated with numerous novel PFASs. Experimental results indicated that perfluoro(3,5,7,9,11-pentaoxadodecanoic) acid (PFO5DoDA) and perfluoro-2,5-dimethyl-3,6-dioxanonanoic acid (C9 HFPO-TA) exhibited higher bioaccumulation potential than perfluorooctanoic acid (PFOA). A multimodal feature-fused directed message passing neural network (FF-DMPNN) model was constructed, integrating molecular graph representations, physicochemical descriptors, and bioassay data reflecting absorption, distribution, metabolism, and excretion characteristics. The FF-DMPNN model demonstrated superior predictive performance compared to conventional machine learning approaches by providing a more complete representation of molecular structures and physicochemical properties, achieving higher accuracy (R2 = 0.742) and robustness in predicting BCF values for PFASs. Application of the model to a comprehensive PFAS database identified 2.45% of chemicals as bioaccumulative, highlighting the need for regulatory attention. Overall, this study provides critical insights into the bioconcentration risks associated with PFASs and offers a reliable framework for prioritizing regulatory actions for these emerging contaminants, addressing a pressing need for their effective environmental management.

Dual-functional metal-organic frameworks for adsorptive removal and ultra-trace quantitation of 50 per- and polyfluoroalkyl substances in water

Per- and polyfluoroalkyl substances (PFAS) are persistent and pervasive environmental contaminants associated with significant health risks. Recent regulatory shifts reducing safe drinking water advisory limits to parts-per-quadrillion (pg/L) levels underscore the urgent need for robust methodologies capable of detecting and removing PFAS at ultra-trace concentrations. In this study, six metal-organic frameworks (MOFs) were systematically evaluated for their dual functionality to preconcentrate PFAS for ultra-trace analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and as sorbents for adsorptive removal of PFAS from water at environmentally relevant concentrations (200 pg/L to 2 µg/L). UiO-66 enabled the quantification of 50 PFAS at spiked concentrations as low as 200 pg/L, with detection limits down to 17 pg/L. These results are comparable to, or better than conventional technical sorbents in LC-MS/MS workflows involving 50 PFAS, whilst using less sorbent (100 vs 250 mg) and volume (250 vs 1000 mL) per sample. In parallel, UiO-67 removed an average of 99% of all 50 PFAS (2 µg/L) from water within 30 min using 10 mg of material. Together, these findings demonstrate the viability of MOFs for both ultra-trace analysis and removal of diverse PFAS chemistries in environmental water matrices, offering a promising strategy for integrated environmental monitoring and treatment.

Identification and environmental occurrence of novel per- and polyfluoroalkyl substances derived from lithium-ion battery

Global rise in electric vehicle adoption has prompted the rapid expansion of the lithium-ion battery (LIB) manufacturing and recycling industry. Many emerging classes of per- and polyfluoroalkyl substances (PFASs) have been incorporated into the LIB. However, the potential for PFAS emissions to the environment during the manufacturing and recycling processes of the LIB remains poorly understood. In this study, characteristic fragment ion-based non-target analysis was conducted to screen and identify unknown PFASs in surface water and sediment samples surrounding several LIB manufacturing and recycling factories. In total, 33 PFASs belonging to eight classes were identified in collected environmental samples with the confidence level of 1 - 3. Among these PFASs, environmental occurrence of N-ethyl perfluoromethanesulfonamide, N-hydroxymethyl trifluoromethanesulfonamide, and a series of bisperfluoroalkane sulfonimides (Bis-FASIs) is first discovered in this study. Furthermore, this study also investigated the sediment-water partitioning behaviors of these identified 33 PFASs. Results showed that the calculated mean log Koc values in all sampling regions ranged from 0.51 ± 0.16 to 3.5 ± 0.34 for C2-C12 perfluoroalkyl carboxylates, 1.0 ± 0.31 to 2.9 ± 0.35 for C1-C8 perfluoroalkyl sulfonates, 1.2 ± 0.20 to 2.1 ± 0.19 for C1-C4 perfluoroalkane sulfonamides, and 1.9 ± 0.35 to 3.3 ± 0.16 for Bis-FASIs. In general, the log Koc values of each class of PFASs linearly (p < 0.05) increased with increasing number of fluorinated carbons. This study discovered seven novel PFASs, which underscores the need to expand regulatory monitoring beyond legacy PFASs. The findings of this study also highlight the urgency of assessing ecological and human health risks posed by LIB-derived PFASs, particularly their potential for long-range transport and persistence in aquatic systems.

Distinctively Different Effects of Perfluorobutanoic Acid and Perfluorononanoic Acid on Zebrafish Sex Differentiation and Androgen Receptor Activity

With the prohibition of perfluorooctanoic acid (PFOA), the emergence of alternative perfluoroalkyl substances such as perfluorobutanonic acid (PFBA) and perfluorononanoic acid (PFNA) in various environmental matrices has led to concerns about their adverse effects on humans and biota. This study aims to investigate the reproductive and developmental toxicity of PFBA and PFNA by combined in vivo, in vitro, and in silico approaches. Examination of juvenile zebrafish exposed to PFBA at environmental concentrations by histopathology, sex hormone, and gene expression revealed accelerated development of zebrafish toward males, while exposure to PFNA during sex differentiation resulted in feminization. In accordance with the in vivo results, PFBA activated the androgen receptor (AR) signaling pathway, but PFNA inhibited it in both prostate cancer cell proliferation and luciferase reporter gene assays. Similarly, the differential binding mode of the two chemicals to AR was shown in the molecular docking analysis, with PFBA exhibiting higher potency for the agonist conformation and PFNA favoring the antagonistic conformation. Together, these results suggest that, while PFNA exhibited similar effects on sex differentiation and AR activity as PFOA, PFBA showed distinctive effects and deserves particular attention and further investigation.

PFAS in Iowa drinking water sources: Chemical and geospatial patterns

Per- and polyfluoroalkyl substances (PFAS) are toxic, persistent, and ubiquitous contaminants which are harmful to the environment and human health. We analyzed publicly accessible records of PFAS concentrations in surface water and groundwater used for public drinking water supplies across the state of Iowa, along with groundwater from private wells near suspected contamination sources. We analyzed these data using the Mann-Whitney U test, principal component analysis, analysis of variance, and Tukey's honestly significant difference test to identify contamination patterns at the regional and local scale. Results indicate that surface water sources across the state are much more likely to contain PFAS than groundwater sources (i.e., 94 % vs. 30 %), but among contaminated public water sources, groundwater has a higher average total PFAS concentration than surface water (i.e., 43.9 ng/L vs. 9.8 ng/L). Two short-chain PFAS (PFBA and PFPeA) dominate surface water sources across the state apart from the Mississippi River, which contains elevated concentrations of PFOS and PFOA. The Mississippi River also influences groundwater within the breadth of its floodplain and associated alluvial aquifer; most groundwater under the influence of the Mississippi River has a similar PFAS fingerprint to the river itself and contains greater concentrations of PFBA than is typical of contaminated groundwaters located outside the influence of the river. Case studies from public and private wells in four PFAS-impacted communities further illustrate that despite regional-scale patterns, PFAS contamination of non-alluvial groundwater often reflects highly local point sources, including firefighting activities and fluorochemical manufacturing, storage, or use. These results demonstrate the utility of regional analyses for characterizing PFAS threats to water supplies and contextualizing local PFAS data in spite of complex source mixtures and fate and transport behavior.

Microplastics magnify inhibitive effects of perfluorooctanoic acid on the marine microbial loop

The marine microbial loop comprising picophytoplankton, bacteria and microzooplankton is essential in global carbon cycling, which is currently affected by anthropogenic pollutants. Nonetheless, the impact of anthropogenic pollutants on the marine microbial loop remains elusive. In this study, perfluorooctanoic acid (PFOA) and microplastics (MPs) were selected as representative anthropogenic pollutants to investigate their impacts on the marine microbial loop with Prochlorococcus MED4 (picophytoplankton), Alteromonas macleodii EZ55 (bacteria), Pseudocohnilembus persalinus and Cafeteria roenbergensis (microzooplankton) as model microorganisms. The picophytoplankton was identified to be most sensitive to PFOA with a sensitivity order of MED4 > EZ55 > C. roenbergensis > P. persalinus. In contrast, polystyrene (PS) as a representative MP had less inhibition on the microbial loop, but synergistically magnified the inhibitive effects of PFOA on those four microorganisms. Moreover, PS significantly (p < 0.05) enhanced the bioconcentration and biomagnification of PFOA in the marine microbial loop, e.g., 1.89, 1.33, 1.22, and 2.18-fold increase in bioconcentration factor values in MED4, EZ55, P. persalinus and C. roenbergensis, respectively, compared to sole PFOA exposure. These results highlighted the exacerbated ecological risk of the co-existence of PFOA and MPs and provides the first insight into impacts of PFOA and PS on the marine microbial loop.

Emerging and legacy per- and polyfluoroalkyl substances from offshore oilfields and receiving water in China

Per- and polyfluoroalkyl substances (PFASs) are extensively utilized as oilfield production chemicals and aqueous film-forming foams (AFFFs) in oilfields. A comprehensive investigation was undertaken to analyze twenty per-and polyfluoroalkyl substances (PFASs), including three emerging PFASs in drill cuttings, slurry and produced water from offshore oilfields in three main sea areas of China. The investigation results were further compared with those in their receiving water. The concentration ranges of ΣPFASs in drill cuttings, slurry as well as produced water were 1049-3473 ng/g and 81.9 ng/L-2090 ng/L, respectively. In comparison, the concentrations range of PFASs in receiving water was 46.2-99.7 ng/L. Both sodium p-perfluorous nonenoxybenzenesulfonate (OBS) and hexafluoropropylene oxide dimer acid (HFPO-DA) were identified as the predominant PFASs detected at elevated concentrations in drilling cuttings, slurry, and produced water, demonstrating their extensive utilization in such environments. HFPO-DA and OBS concentrations in produced water exceeded those in receiving water by 1-2 orders of magnitude. Principal component analysis (PCA) analyses revealed that the compositions of PFASs in the receiving water samples exhibited significant similarity to those in drill cuttings, slurry and produced water from oilfields. It was indicated that discharges from oilfields were the primary contributors of PFASs in their receiving water. In 60-96% of samples from produced water in the Bohai Sea and South China Sea oilfields, as well as receiving water adjacent to the Bohai Sea oilfields, the risk quotient (RQ) of HFPO-DA ranged 0.1-1, indicating moderate ecological risks to aquatic organisms. In contrast, legacy PFASs generally showed lower risk levels.

The quest for the perfect "total PFAS" method: how can the total oxidisable precursor (TOP) assay be made reliable?

Per- and polyfluoroalkyl substances (PFAS) make up a large and complex class of manmade chemicals. They have been widely used in numerous industrial branches and are incorporated into many consumer products. Today, there is a consensus on the fact that PFAS are present in all environmental compartments and that populations all over the world are subjected to them via internal exposure. It has been estimated that thousands of individual PFAS have been manufactured and marketed since the 1950s, to which impurities present in commercial products and intermediate environmental transformation products should be added. Since it is unrealistic to be able to individually identify, detect and quantify all the PFAS present in a sample, several analytical approaches have been developed to assess the presence of "hidden/unseen" PFAS. One of these, known as the total oxidisable precursor (TOP) assay, was first described in 2012. Basically, it converts some PFAS, hereafter referred to as precursors, into stable terminal products readily measurable by routine target methods. This review is based on more than 100 studies in which the original TOP assay was simply applied or optimised. The review found that the TOP assay was selective, sensitive, applicable to many matrices, useful within a forensic context, inexpensive, and easy to implement and has been assessed in the literature on a wide range of precursors. However, this method comprises many subtleties and has some flaws that operators should be made aware of so that they may be addressed as far as possible. Finally, this review tries to lay the foundations for better practices and quality assurance/quality control measures, in order to improve accuracy and reliability of TOP assay results.

Roadmap to Catalytic Abatement of Gas Phase Per- and Polyfluoroalkyl Substances (PFAS)

While the outstanding stability of per- and polyfluoroalkyl substances (PFAS) paved the way for their widespread application in a huge variety of applications, it also resulted in their nickname "forever chemicals". The rising awareness for PFAS-related environmental and health concerns drives a discussion on the most effective ways to abate PFAS emissions into the environment, i.e. water, soil, and air, and remediation of contaminated matter. In order to address the knowledge gap regarding air pollution by PFAS, this minireview summarizes the current corpus of work in the field and outlines how catalysis can contribute to PFAS abatement in the gas phase. Beyond a mere collection of state-of-the-art knowledge, overarching challenges in catalytic PFAS removal are identified, spanning from fundamental organic and inorganic chemistry, i.e. C-F-bond activation, to heterogeneous catalysis, i.e. surface reactions at the gas-solid interface, to reaction engineering, i.e. scaling relations and technical hurdles. In addition, the article introduces concepts and workflows that aim at providing guidance during the design of technological solutions for the efficient control of gaseous PFAS emissions.

Association between perfluoroalkyl and polyfluoroalkyl substances and adolescents' sleep disorders: NHANES 2005-2018

Background

Previous research indicates that per- and polyfluoroalkyl substances (PFAS) can disrupt metabolism and neurological function via endocrine pathway interference and neuroinflammation. These effects may impair melatonin secretion and disrupt circadian rhythm regulation, suggesting potential links to sleep health. However, the impact of PFAS exposure on adolescent sleep remains unclear. This study examines the associations between PFAS exposure and sleep health indicators in U.S. adolescents.

Methods

Data from 838 adolescents who participated in the 2005-2018 National Health and Nutrition Examination Survey (NHANES) were analyzed to investigate the association between PFAS exposure and physician-diagnosed sleep disorders. Eight PFAS compounds were identified. Multivariate logistic regression models, restricted cubic spline (RCS) curves, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression were used to assess single, linear, and combined effects on adolescent sleep disorders.

Results

Negative associations were observed between adolescent sleep disorders and three PFAS compounds, specifically perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and perfluorononanoic acid (PFNA). RCS analysis revealed a significant linear relationship (P for non-linear > 0.05). The BKMR and WQS models demonstrated a combined effect of PFAS exposure on sleep disorders, with PFOS demonstrating the most substantial contribution (effect size: 0.91). The stratified analysis revealed that PFOS exposure had a greater impact on females [odds ratio (OR): 0.54, 95% confidence interval (CI): 0.33-0.87] than males (OR: 0.50, 95% CI: 0.24-1.01), suggesting sex-specific differences in vulnerability.

Conclusions

Our findings indicate a negative correlation between specific PFAS and specific sleep disorders in adolescents, with PFOS being the dominant effect component in the PFAS mixture and stronger effects observed in females. However, due to the cross-sectional nature of the study, a causal relationship cannot be established. These results highlight the potential public health impact of PFAS exposure and the need to further investigate the underlying mechanisms and causal pathways in future longitudinal or experimental studies.

Realizing Direct Hot-Electron Transfer from Metal Nanoparticles to Per- and Polyfluoroalkyl Substances

Per- and polyfluoroalkyl substances (PFAS) are a group of forever synthetic chemicals. They are widely utilized in industries and household appliances because of their remarkable stability and distinctive oil- and water-repellent properties. Despite their broad applications, unfortunately, PFAS are hazardous to all forms of life, including humans. In recent years, the environmental persistence of PFAS has raised significant interest in degrading these substances. However, the strong C-F bonds in these chemicals pose several challenges to their degradation. Plasmons of noble metal nanoparticles (NPs) offer many exciting applications, including photocatalytic reactions. However, an atomistic understanding of plasmon-driven processes remains elusive. In this work, using the real-time time-dependent density functional theory, we have studied the real-time formation of plasmons, hot-carrier generation, and subsequent direct hot-carrier transfer from metal NPs to the PFAS. Our simulations show that there is an apparent direct hot-electron transfer from NPs to PFAS. Moreover, using Ehrenfest dynamics simulations, we demonstrated that the transferred hot electrons can efficiently degrade PFAS without requiring any external thermal bath. Thus, our work provides an atomistic picture of plasmon-induced direct hot-carrier transfer from NPs to PFAS and the efficient degradation of PFAS. We strongly believe that this work generates the impetus to utilize plasmonic NPs to mitigate PFAS.

Hold My Beer: The Linkage between Municipal Water and Brewing Location on PFAS in Popular Beverages

Beer has been a popular beverage for millennia. As water is a main component of beer and the brewing process, we surmised that the polyfluoroalkyl substances (PFAS) presence and spatial variability in drinking water systems are a PFAS source in beers. This is the first study to adapt EPA Method 533 to measure PFAS in beer from various regions, brewery types, and water sources. Statistical analyses were conducted to correlate PFAS in state-reported drinking water, and beers were analyzed by brewing location. PFAS were detected in most beers, particularly from smaller scale breweries located near drinking water sources with known PFAS. Perfluorosulfonic acids, particularly PFOS, were frequently detected, with PFOA or PFOS above U.S. EPA's Maximum Contaminant Limits in some beers. There was also a county-level correlation between the total PFAS, PFOA, and PFBS concentrations in drinking water and beers. Given that approximately 18% of U.S. breweries are located within zip codes with detectable PFAS in municipal drinking water, our findings, which link PFAS in beer to the brewery water source, are intended to help inform data-driven policies on PFAS in beverages for governmental agencies, provide insights for brewers and water utilities on treatment needs, and support informed decision-making for consumers.