Per- and polyfluoroalkyl substances (PFASs) are now widely detected in drinking water globally as a result of decades of production and use. Although recent regulations aim to address this issue, including the recast EU Drinking Water Directive (DWD), which introduces a PFAS Total parametric value, no standardized analytical method has yet been established for their determination. Here, extractable organofluorine (EOF) analysis of drinking water using combustion ion chromatography (CIC) was evaluated as a proxy for assessing PFAS Total under the EU DWD. Due to the low recovery of trifluoroacetic acid (TFA) in the EOF extraction, a workflow was presented that separated TFA from the PFAS Total reporting. The impact of different fluorine mass fractions on the conversion factor used to translate EOF concentrations into a PFAS Total parametric value was evaluated. Based on this discussion, PFOA (67% F) was selected as a representative reference compound. Due to the broad, non-specific coverage of the EOF method, contributions from non-PFAS organofluorine compounds or inorganic fluorinated species may occur, potentially inflating the PFAS Total parametric value. Therefore, a structured follow-up protocol for investigation of PFAS Total parametric value exceedance was presented to support the use of EOF-CIC as a screening and compliance-support tool.

Per- and polyfluoroalkyl substances (PFAS) are an extensive group of anthropogenic compounds with a large diversity of classes. Relying only on target analysis may underestimate the level of PFAS contamination in the environment. The extractable organofluorine (EOF) mass balance is a widely applied method to estimate the fraction of organofluorine not captured by target analysis. This study aimed to conduct a comprehensive EOF mass balance analysis on sludge and evaluate the impact of three different sample treatments on target PFAS and EOF, as well as their respective mass balance. Two complementary sample treatments were applied to 26 Swedish sludge samples: ion-pair extraction (IPE) for anionic and neutral PFAS, and hexane:acetone extraction (Hx:Ac) for nonpolar PFAS. The results demonstrated that the EOF concentrations were highly influenced by the sample treatment. The IPE method observed up to 40 times higher EOF concentrations than the Hx:Ac method, indicating a high proportion of polar organofluorine. Unidentified EOF increased between 2004 and 2017 for both sample treatments. These findings demonstrate that both polar and nonpolar organofluorine contribute to the EOF and that no single method captures them. In the present study, only two side-chain fluorinated copolymers were monitored, and other fluorinated polymers may be contributors to the unknown EOF.

Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals that accumulate externally and internally in the environment and in humans, and which pose risks to health. While rather low EU and national environmental limits exist for perfluoroalkyl acids (PFAA) in water and food, industrial PFAS emissions are hardly regulated. Residents living near fluoropolymer (FP) manufacturing plants (MPs) which (re-)coat FPs on metals and other surfaces may therefore be exposed to FP related PFAS. This pilot study aimed to 1) investigate pollution around a Danish FPMP and 2) to develop a sampling and analysis strategy independent of access to the factory. To this end, we compiled a list of PFAS suspected to be used, formed and emitted, and conducted a local-scale air dispersion modelling (OML) to predict the spread of gases. This informed where to sample 23 bird eggs (blackbirds, great tit), 10 snails (Helix pomatia), and lake water at varying distances from the factory. A combined analytical strategy was applied to the samples, using target analysis (PFAS33), suspect/non-target screening (SS/NTS), and extractable organofluorine-combustion ion chromatography (EOF-CIC). Near the factory, the eggs had elevated organofluorine levels (blackbirds: 670-2,500 ng/g; great tits: 260-670 ng/g), fourfold higher for blackbirds than in the controls. PFAS33 explained only 1.0-4.7% of EOF, indicating substantial unidentified organofluorines (UOF). Organofluorine levels in snails were below the LOD, while water samples showed PFAS patterns but were below the NTS confirmation levels. The elevated organofluorine levels in eggs sampled near the factory support the concern that the FPMP has polluted its surroundings.

Effective early warning systems for aquatic contamination require monitoring strategies capable of detecting subtle, long-term shifts in mixture-driven biological activity. Suspended particulate matter (SPM) serves as a carrier and reservoir for complex contaminant mixtures, facilitating their transport and persistence in aquatic systems, yet systematic toxicological time series for archived SPM remain scarce. Regulatory monitoring predominantly targets Priority Substances and River Basin Specific Pollutants, leaving the temporal trends of particle-associated mixture toxicity largely unresolved. Leveraging 18 years (2005-2022) of cryogenically archived annual SPM composites from the Rhine River, we conducted a spatiotemporal effect-based assessment integrating receptor-mediated effects, oxidative stress analysis and untargeted Cell Painting phenomics. This integrated toolbox enabled evaluation of pathway-specific responses and multi-compartment cellular perturbations associated with particle-bound contaminant mixtures. Polar SPM-associated chemicals elicited oxidative stress response and caused endocrine disruption through estrogen receptor α (ERα) activation and androgen receptor inhibition (anti-AR). Trend analysis showed spatiotemporal variation along the river, with statistically increasing trends of oxidative stress and anti-AR activity over time at Koblenz, driven by polar chemicals. Both polar and non-polar SPM extracts activated the aryl hydrocarbon receptor (AhR), indicating presence of compounds capable of triggering xenobiotic response pathways. Several subcellular compartments were affected, with mitochondrial features being among the most affected. These findings demonstrate that SPM-associated chemicals elicit diverse toxicological effects by acting on several receptors and impacting diverse cellular structures. Combining targeted and phenomics-based effect approaches provided comprehensive mechanistic insights and valuable information to support the early warning systems for chemical contamination in aquatic environments.

Per- and polyfluoroalkyl substances (PFAS) are persistent pollutants that raise food safety concerns, especially near contamination hotspots. This study measured 9 PFAS in milk and 15 PFAS in water from 22 Swedish dairy farms <10 km from contamination hotspots and 49 PFAS in milk from 20 regional production facilities. PFOA, PFOS, and PFNA were quantified in 5-77% of milk from dairy farms, with maximum levels of 18, 17, and 10 pg/g milk ww, respectively; the remaining PFAS were below method detection limits (MDL). All PFAS were < MDL at production facilities. One dairy farm milk sample exceeded EU's indicative level for PFOA (10 pg/g), but levels in production facilities suggest limited consumer exposure. No correlation was found between PFAS in farm water and milk, implying other exposure routes may dominate when water contamination is low. While results indicate limited health risks, contamination in other milk-producing regions cannot be ruled out, supporting the need for continued PFAS monitoring in dairy production.

This study applied a virtual effect-directed analysis (vEDA) approach, integrating effect-based analysis and chemical screening, to identify bioactive compounds in rubber infill from artificial turf. Bioreporter assays targeting diverse toxicological endpoints were selected to detect a wide range of potential endocrine-disrupting and genotoxic compounds. Of 21 samples, all except one showed aryl-hydrocarbon receptor (AhR) activity (14-31,400 ng benzo[a]pyrene equivalents/g), four induced p53 activity (0.04-0.86 µg actinomycin D equivalents/g) and two showed estrogen receptor α (ERα) activity (530 and 1020 pg estradiol equivalents/g). Chemical analysis quantified up to 87 polycyclic aromatic compounds (PAC) and gas chromatography high-resolution mass spectrometry-based suspect screening yielded 281 tentative identifications. Annotation with bioassay activity data from databases and predictive models revealed 29 AhR-, 32 ERα- and 18 p53-active compounds. Univariate analysis was used to prioritize compounds for further chemical and toxicological confirmation. Eighteen AhR agonists were confirmed, contributing 0-98% to the observed AhR activity in the samples. Phenylamine additives, detected at high concentrations, exhibited low AhR activating potency and contributed < 1%. In contrast, methylated chrysene isomers elicited relatively high potencies and contributed substantially (≤65%) to the observed AhR activity. N-Isopropyl-N'-phenyl-p-phenylenediamine (IPPD) was confirmed as p53 active and explained ∼50% of the observed activity in the most p53-active sample. Styrene-butadiene rubber (SBR) showed higher AhR- and p53 activities and concentrations of quantified compounds than the alternative materials. The study highlights differences in chemical hazards among rubber infill materials and demonstrates the utility of vEDA as an early-warning tool for identifying compounds of concern.

Comprehensive quantification of per- and polyfluoroalkyl substances (PFAS) and extractable organofluorine (EOF) for assessing PFAS total in complex environmental matrices requires extraction methods capable of retaining chemically diverse fluorinated compounds. In this study, the performance of three solid-phase extraction (SPE) sorbents (weak anion exchange (WAX), weak cation exchange (WCX), and hydrophilic-lipophilic balance (HLB)) was comprehensively evaluated for the extraction of selected targeted PFAS and inorganic anions and determination of extractable fluorine from landfill leachate. Recovery experiments covering multiple PFAS classes, including PFCA, PFSA, zwitterionic PFAS, and bis-FASI, together with inorganic fluorinated anions, showed clear sorbent-dependent selectivity. WAX provided the most consistent recoveries across compound classes and yielded comparable concentrations of Σ33PFAS + BF4− and EOF, indicating retention of a broad fraction of fluorinated compounds and a closed fluorine mass balance. In contrast, WCX resulted in lower EOF concentration and a negative fluorine mass balance, attributed to matrix composition that emerged as a critical factor controlling EOF recovery, with divalent cations (Ca2+ and Mg2+) causing significant EOF suppression. HLB also yielded lower EOF concentrations, primarily due to poor retention of ultra-short-chain PFAS that contributed significantly to the overall fluorine balance, and similar behavior was observed for WCX. In addition, retention of inorganic fluorinated anions indicates that EOF concentrations included both organic and inorganic fluorinated compounds. The findings reveal that both sorbent chemistry and matrix chemistry critically influence EOF quantification, thereby affecting fluorine mass balance.

Chemical pollution can affect ecosystems and human health, highlighting the need for approaches that identify, evaluate, and prioritize emerging chemical risks before they become established public-health issues requiring regulatory actions. This review and perspective article examines methodological components required for Early Warning Systems (EWSs) for chemical risks, with particular attention to the European policy context. It examines methodological components for chemical EWSs rather than proposing a fully implemented system. It considers how state-of-the-art and emerging methods can support signal generation, signal strengthening, prioritization, uncertainty assessment, communication, and follow-up. The reviewed components include matrices and sampling strategies; chemical monitoring, suspect screening, and non-target screening; effect-based methods, New Approach Methodologies, and effect-directed analysis; exposure and hazard modelling; QSAR, read-across, AI-supported and data-mining tools; expert evaluation; and governance processes that link scientific signals to proportionate follow-up. The conceptual workflow is used as an example of how these components may be organized into a signal-handling process, while EU-level developments provide the broader policy and governance context. The actionable value of a chemical EWS does not depend on any single method, but on structured integration of complementary evidence streams. An effective EWS should combine sensitive weak-signal detection with transparent prioritization, explicit uncertainty assessment, FAIR and interoperable data infrastructures, and clearly assigned responsibilities for communication and follow-up.

Previous studies on per- and polyfluoroalkyl substances (PFAS) have indicated large amounts of unidentified organofluorine in municipal wastewater, raising concerns about their environmental impact. Here, a novel multisorbent solid phase extraction method was applied to municipal wastewater samples, followed by liquid chromatography-high-resolution mass spectrometry-based screening and a quantification workflow combining targeted analysis and combustion ion chromatography for fluorine mass balance analysis. Twenty-three highly fluorinated compounds (i.e., perfluoroalkyl acids and precursors) were identified and, apart from trifluoroacetic acid, quantified in the low- to sub-ppt range. In contrast, 30 low-fluorinated substances (i.e., active pharmaceutical ingredients, pesticides, and transformation products, including some previously unreported metabolites) were identified and quantified at concentrations up to 3 orders of magnitude higher. Despite their lower fluorine content (<30% by mass), these pharmaceuticals accounted for 28-42% of the extractable (organo)fluorine (EOF), with sitagliptin, bicalutamide, and celecoxib carboxylic acid being important drivers of the EOF. The inorganic fluoroanions hexafluorophosphate and tetrafluoroborate were coextracted and contributed 7-19% of the EOF. The multisorbent approach also captured polar cationic pharmaceuticals, substantially influencing the EOF composition. These findings highlight the complexity of fluorine mass balance in municipal wastewater and the need for advanced methods to uncover unidentified organofluorine.

BACKGROUND:Some per- and polyfluoroalkyl substances (PFAS) such as perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are very long-lived in humans, with serum half-lives of several years. In PFAS hot spots, such as Ronneby, Sweden, high exposures over time have led to markedly elevated serum PFAS levels, which may result in health risks as well as transfer to the next generation through pregnancy and breastfeeding. Bile acid sequestrants and organic anion transporter inhibitors are drug candidates for increasing PFAS elimination in humans. MATERIALS AND METHODS:This is a cross-over, clinical study in 10 individuals from Ronneby, Sweden. First, participants were given the bile acid sequestrant cholestyramine and the organic anion transporter inhibitor probenecid for 1 week each. Urinary and fecal concentrations were measured prior, during and after the administration. Then, the changes of serum PFAS concentrations during a 12-week intervention with the bile acid sequestrant colesevelam were compared to a control period. RESULTS:The study population was mainly exposed to PFHxS (serum mean 50 ng/mL, range 5.8-170), PFOS (serum mean 46 ng/mL, range 9.2-130) and PFOA (serum mean 2.2, range 0.7-4.4). Cholestyramine intervention increased the serum adjusted fecal PFOS concentrations by 23.1 times (95 %CI: 13.6, 39.2), while probenecid was associated with 0.79 times (95 %CI 0.63, 1.0) serum-adjusted urinary PFOS concentrations, compared to no intervention. The 12-week intervention with colesevelam resulted in a mean serum PFOS decline of 38 % (95 %CI -42, -34), compared to 2 % (95 %CI -8, 5) in the control period. The decline was smaller for PFHxS and PFOA. CONCLUSIONS:Bile acid sequestrants could be used for accelerating PFAS excretion in highly PFAS exposed individuals. Studies are needed to evaluate the risks, costs and benefits of using it for this purpose.

As the volume of plastic waste from electrical and electronic equipment (WEEE) continues to rise, a significant portion is disposed of in the environment, with only a small fraction being recycled. Both disposal and recycling pose unknown health risks that require immediate attention. Existing knowledge of WEEE plastic toxicity is limited and mostly relies on epidemiological data and association studies, with few insights into the underlying toxicity mechanisms. Therefore, this study aimed to perform comprehensive chemical screening and mechanistic toxicological assessment of WEEE plastic-associated chemicals. Chemical analysis, utilizing suspect screening based on high-resolution mass spectrometry, along with quantitative target chemical analysis, unveiled numerous hazardous compounds including polyaromatic compounds, organophosphate flame retardants, phthalates, benzotriazoles, etc. Toxicity endpoints included perturbation of morphological phenotypes using the Cell Painting assay, inflammatory response, oxidative stress, and endocrine disruption. Results demonstrated that WEEE plastic chemicals altered the phenotypes of the cytoskeleton, endoplasmic reticulum, and mitochondria in a dose-dependent manner. In addition, WEEE chemicals induced inflammatory responses in resting macrophages and altered inflammatory responses in lipopolysaccharide-primed macrophages. Furthermore, WEEE chemicals activated the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, indicating oxidative stress, and the aryl hydrocarbon receptor (AhR). Endocrine disruption was also observed through the activation of estrogenic receptor-α (ER-α) and the induction of anti-androgenic activity. The findings show that WEEE plastic-associated chemicals exert effects in multiple subcellular sites, via different receptors and mechanisms. Thus, an integrated approach employing both chemical and toxicological methods is essential for comprehensive assessment of the toxicity mechanisms and cumulative chemical burden of WEEE plastic-associated chemicals.

BACKGROUND:Many poly- and perfluoroalkyl substances (PFAS) are persistent and have long half-lives in the human body. However, there are limited data on the different routes of elimination. Most pharmacokinetic models assume that the urinary route dominates. OBJECTIVES:Our aim was to investigate the relative importance of fecal and urinary elimination for linear perfluorooctane sulfonic acid (L-PFOS), branched PFOS and perfluorooctanoic acid (PFOA), and to estimate volumes of distributions (Vds). METHODS:Drinking water highly contaminated with PFAS from firefighting foam was distributed to many households in Ronneby, Sweden, from the 1980s to December 2013. In 2016, PFAS levels were measured in matched serum, feces and urine samples from 147 subjects. Daily urinary and fecal PFAS elimination was estimated through urinary creatinine elimination and dry fecal mass, respectively. Longitudinal serum PFAS elimination rates were used together with fecal and urinary elimination rates to estimate Vds. RESULTS:In 2016, the median serum concentrations were 100 ng/mL for L-PFOS and 10 ng/mL for PFOA. L-PFOS was eliminated primarily through feces, with a median urinary elimination of 91 ng/day and median fecal elimination of 364 ng/day. The branched PFOS had, similarly, a primarily fecal elimination. In contrast, PFOA had a slightly higher urinary elimination, with median urinary elimination of 26 ng/day and fecal elimination of 15 ng/day. Median Vds were estimated at 93 mL/kg for PFOS and 74 mL/kg for PFOA. CONCLUSION:Fecal elimination was shown to be an important route for PFOS and PFOA elimination. Pharmacokinetic models need to take fecal elimination into consideration.

Per- and polyfluoroalkyl substances (PFAS) and fluorinated ionic liquids were investigated in municipal effluents from 30 wastewater treatment plants (WWTPs) across 15 European countries using supercritical fluid chromatography-high-resolution mass spectrometry (SFC-HRMS) for nontarget screening. Bis-perfluoroalkyl sulfonimide (bis-FASI) ionic liquids were detected as bis(trifluoromethanesulfonyl)imide (NTf2-), two rarely reported homologues (±2 CF2, namely FSI- and BETI-), and two previously unreported homologues (±1 CF2, namely FTFSI- and FTNTf2-). Bis-FASIs were present in 85% of samples and were more abundant in effluents from larger WWTPs. The fluorinated anion PF6-, commonly used in ionic liquids, was found in all samples (≤3 μg/L). Hexafluoroarsenate (AsF6-), reported here for the first time in municipal wastewater, was detected in 32% of samples in eight countries. PF6- and AsF6- concentrations exceeded those of traditional PFSAs and PFCAs in 97% of the samples. No removal was detected for perfluorinated compounds, inorganic anions, and low-fluorinated pharmaceuticals and pesticides. Low-fluorinated substances were detected in 90% of samples (>100 ng/L), yet PF6- alone surpassed the combined concentration of all low-fluorinated substances in 27 out of 30 samples. These results reveal the significance of unconventional fluorinated substances for the overall fluorine load in wastewater, highlighting the need to extend monitoring strategies beyond legacy PFAS.

The continuous release of synthetic chemicals into aquatic systems underscores the need for long-term assessments of contaminants of emerging concern (CECs). Archived suspended particulate matter (SPM) samples from the German Environmental Specimen Bank (ESB) (2005-2022) at two Rhine sites (Weil am Rhein and Koblenz) were analyzed using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) suspect/non-target screening (SS/NTS) to evaluate temporal trends. Using retention-time indices and orthogonal MS/MS evidence (mzCloud, FISh, CFM-ID), 332 compounds were identified at varying Schymanski confidence levels (2.1: 3.0 %; 2.2: 5.7 %; 3.1: 53 %; 3.2: 38 %). Temporal analysis of LC-HRMS peak areas revealed that 25 % of contaminants increased over time, with a higher proportion at Koblenz (29 %) than Weil (18 %). Conversely, several compounds exhibited statistically significant decreasing trends at both Koblenz (14 %) and Weil sites (13 %), consistent with regulatory measures, improved wastewater treatment, and shifts in industrial practices. Aquatic toxicity prediction (ECOSAR) indicated that 47 % (154 of 332) of annotated structures were highly acutely toxic (LC₅₀/EC₅₀ ≤ 1 mg/L) to at least one test group (fish, Daphnia, or green algae). This study provides the first 18-year, site-specific non-target time series from a national archive and integrating orthogonal identification with hazard prediction to support chemical prioritization. Archived SPM enables retrospective and comparable assessment of particle-associated contaminants, complementing dissolved-phase monitoring, and supporting the identification of unmonitored emerging CECs. Crucially, long-term NTS of these SPM samples provides screening-level early-warning signals and a watch list for targeted confirmation and risk management.

Existing regulatory frameworks often prove inadequate in identifying contaminants of emerging concern (CECs) and determining their impacts on biological systems at an early stage. The establishment of Early Warning Systems (EWSs) for CECs is becoming increasingly relevant for policy-making, aiming to proactively detect chemical hazards and implement effective mitigation measures. Effect-based methodologies, including bioassays and effect-directed analysis (EDA), offer valuable input to EWSs with a view to pinpointing the relevant toxicity drivers and prioritizing the associated risks. This review evaluates the analytical techniques currently available to assess biological effects, and provides a structured plan for their systematic integration into an EWS for hazardous chemicals in the environment. Key scientific advancements in effect-based approaches and EDA are discussed, underscoring their potential for early detection and management of chemical hazards. Additionally, critical challenges such as data integration and regulatory alignment are addressed, emphasizing the need for continuous improvement of the EWS and the incorporation of analytical advancements to safeguard environmental and public health from emerging chemical threats.

Per- and polyfluoroalkyl substances (PFAS) are persistent anthropogenic contaminants, some of which are toxic and bioaccumulative. Perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) can form during the atmospheric degradation of precursors such as fluorotelomer alcohols (FTOHs), N-alkylated perfluoroalkane sulfonamides (FASAs), and hydrofluorocarbons (HFCs). Since PFCAs and PFSAs will readily undergo wet deposition, snow and ice cores are useful for studying PFAS in the Arctic atmosphere. In this study, 36 PFAS were detected in surface snow around the Arctic island of Spitsbergen during January-August 2019 (i.e., 24 h darkness to 24 h daylight), indicating widespread and chemically diverse contamination, including at remote high elevation sites. Local sources meant some PFAS had concentrations in snow up to 54 times higher in Longyearbyen, compared to remote locations. At a remote high elevation ice cap, where PFAS input was from long-range atmospheric processes, the median deposition fluxes of C2-C11 PFCAs, PFOS and HFPO-DA (GenX) were 7.6-71 times higher during 24 h daylight. These PFAS all positively correlated with solar flux. Together this suggests seasonal light is important to enable photochemistry for their atmospheric formation and subsequent deposition in the Arctic. This study provides the first evidence for the possible atmospheric formation of PFOS and GenX from precursors.

InfoMetricsFiguresRef. Environmental Science & TechnologyASAPArticle This publication is Open Access under the license indicated. Learn More CiteCitationCitation and abstractCitation and referencesMore citation options ShareShare onFacebookX (Twitter)WeChatLinkedInRedditEmailJump toExpandCollapse ViewpointAugust 14, 2024A Systematic Workflow for Compliance Testing of Emerging International Classwide Restrictions on PFASClick to copy article linkArticle link copied!Robin Vestergren*Robin VestergrenSwedish Chemicals Agency (KEMI), 17266 Stockholm, Sweden*[email protected]More by Robin VestergrenView BiographyAnders AppelblomAnders AppelblomSwedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenMore by Anders AppelblomSimona A. BălanSimona A. BălanCalifornia Department of Toxic Substances Control, Berkeley, California 94710, United StatesMore by Simona A. Bălanhttps://orcid.org/0000-0003-0438-1616Sicco H. BrandsmaSicco H. BrandsmaAmsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The NetherlandsMore by Sicco H. BrandsmaThomas A. BrutonThomas A. BrutonCalifornia Department of Toxic Substances Control, Sacramento, California 95814, United StatesMore by Thomas A. Brutonhttps://orcid.org/0000-0002-4090-6021Ian T. CousinsIan T. CousinsDepartment of Environmental Science, Stockholm University, 10691 Stockholm, SwedenMore by Ian T. Cousinshttps://orcid.org/0000-0002-7035-8660Jeremy R. GauthierJeremy R. GauthierDepartment of Chemistry, University of Toronto, Toronto, ON M5S 3H6, CanadaMore by Jeremy R. Gauthierhttps://orcid.org/0000-0002-6446-706XAudun HeggelundAudun HeggelundNorwegian Environment Agency, Box 5672, Torgarden, N-7485 Trondheim, NorwayMore by Audun Heggelundhttps://orcid.org/0009-0003-6900-0316Jenny IvarssonJenny IvarssonSwedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenMore by Jenny IvarssonAnna KärrmanAnna KärrmanSchool of Science and Technology, Örebro University, 70182 Örebro, SwedenMore by Anna KärrmanLisa MelymukLisa MelymukRECETOX, Faculty of Science, Masaryk University, 61137 Brno, Czech RepublicMore by Lisa Melymukhttps://orcid.org/0000-0001-6042-7688Chijioke OlisahChijioke OlisahRECETOX, Faculty of Science, Masaryk University, 61137 Brno, Czech RepublicMore by Chijioke Olisahhttps://orcid.org/0000-0002-7714-3056Amanda RosenAmanda RosenSwedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenMore by Amanda RosenEleni K. SavvidouEleni K. SavvidouDepartment of Environmental Science, Stockholm University, 10691 Stockholm, SwedenMore by Eleni K. Savvidouhttps://orcid.org/0009-0001-0662-6202Steffen SchellenbergerSteffen SchellenbergerRISE Research Institutes of Sweden AB, Environment and Sustainable Chemistry Unit, 11428 Stockholm, SwedenMore by Steffen Schellenbergerhttps://orcid.org/0000-0001-8001-6851Lisa SkedungLisa SkedungRISE Research Institutes of Sweden AB, Department Materials and Surface Design, 11428 Stockholm, SwedenMore by Lisa Skedunghttps://orcid.org/0000-0001-6657-1592Petteri TalasniemiPetteri TalasniemiFinnish Safety and Chemicals Agency (Tukes), Box 66, 00521 Helsinki, FinlandMore by Petteri TalasniemiTonie WickmanTonie WickmanRISE Research Institutes of Sweden AB, The Swedish Centre for Chemical Substitution, 11428 Stockholm, SwedenMore by Tonie WickmanJonathan ZweigleJonathan ZweigleEnvironmental Analytical Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, GermanyMore by Jonathan Zweiglehttps://orcid.org/0000-0002-7194-1567Christian ZwienerChristian ZwienerEnvironmental Analytical Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, GermanyMore by Christian Zwienerhttps://orcid.org/0000-0002-6682-5828Jonathan P. Benskin*Jonathan P. BenskinDepartment of Environmental Science, Stockholm University, 10691 Stockholm, Sweden*[email protected]More by Jonathan P. BenskinView Biographyhttps://orcid.org/0000-0001-5940-637XOpen PDFEnvironmental Science & TechnologyCite this: Environ. Sci. Technol. 2024, XXXX, XXX, XXX-XXXClick to copy citationCitation copied!https://pubs.acs.org/doi/10.1021/acs.est.4c06570https://doi.org/10.1021/acs.est.4c06570Published August 14, 2024 Publication History Received 29 June 2024Published online 14 August 2024article-commentary© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0. 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License Summary*You are free to share(copy and redistribute) this article in any medium or format and to adapt(remix, transform, and build upon) the material for any purpose, even commercially within the parameters below: Creative Commons (CC): This is a Creative Commons license. Attribution (BY): Credit must be given to the creator. View full license *DisclaimerThis summary highlights only some of the key features and terms of the actual license. It is not a license and has no legal value. Carefully review the actual license before using these materials. ACS Publications© 2024 The Authors. Published by American Chemical SocietySubjectswhat are subjectsArticle subjects are automatically applied from the ACS Subject Taxonomy and describe the scientific concepts and themes of the article.AlkylsFluorineNuclear magnetic resonance spectroscopyPrecursorsTesting and assessmentThe poorly reversible risks to human health and ecosystems from contamination with per- and polyfluoroalkyl substances (PFAS) have led many researchers and regulators worldwide to call for a classwide ban of these so-called forever chemicals. As part of the EU Chemicals Strategy for Sustainability, the national authorities of five European countries submitted a broad restriction proposal on PFAS under REACH in January 2023. This restriction proposal is unique in its scope by including the vast majority of uses for >10 000 substances that meet the OECD definition of PFAS. (1) In parallel, several countries and multiple states in the United States have proposed or enacted broad PFAS restrictions for all non-essential uses or for specific uses and reporting requirements for a range of consumer products. Although the regulatory frameworks underpinning these restrictions contain many differences, the proposed restrictions have the common objective to ban the intentional use of all PFAS and thus avoid regrettable substitution with other PFAS. Given that the proposed restrictions apply to chemical products and articles (both hereafter termed simply "products") that are imported from other states, countries, or regions, they may also trigger substitution and an increased demand for supply chain information on a global level. Direct communication with manufacturers and distributors is typically the primary approach for companies to ensure compliance with chemical regulations. Nevertheless, companies and authorities require reliable analytical methods to independently verify supply chain information and capture products that are noncompliant with PFAS restrictions.A major challenge for compliance testing stems from the sheer number and structural diversity of PFAS, making it impossible for a single analytical method to quantify all PFAS individually. There are, however, a growing number of analytical methods that can indicate the presence of PFAS by leveraging certain characteristics of these chemicals. Building on the recent advances in the analytical chemistry of PFAS, we discuss the currently available analytical methods that can inform compliance testing of PFAS in different products under different regulatory frameworks while highlighting the advantages and remaining challenges associated with these methods. We then illustrate how these methods could be applied in a three-step workflow for the implementation of the PFAS restriction proposal under REACH (Figure 1). Notably, this Viewpoint is not intended to review or comment on individual or classwide PFAS risk assessments that have been carried out by different authorities but rather to present an approach for ensuring compliance with these new laws based on recent advances in analytical chemistry.Figure 1Figure 1. Three-step workflow that companies or authorities could implement to assess noncompliance with the proposed broad restriction of per- and polyfluoroalkyl substances (PFAS) under REACH. The submitted REACH restriction proposal has set guideline levels for both total fluorine (TF) and individual and/or sum of PFAS concentrations (ΣPFAS) with three guideline values in products: (1) 50 ppm (mg/kg) fluorine for PFAS, including polymeric PFAS; (2) 25 ppb for any PFAS measured by target analysis, excluding polymeric PFAS; and (3) 250 ppb for ΣPFAS measured by target analysis, which can optionally involve measurement of PFAS after the transformation of precursors [e.g., via the total oxidizable precursor (TOP) assay]. Because a full characterization of all commercially available PFAS, their impurities, and their degradation products is not practically feasible, this workflow is designed to efficiently identify noncompliant products using a tiered approach. Abbreviations: CIC, combustion ion chromatography; PIGE, particle-induced γ-ray emission; pyr-GCMS, pyrolysis-gas chromatography-mass spectrometry; 19F NMR, 19F nuclear magnetic resonance; LC-MS/MS, liquid chromatography-tandem mass spectrometry; PFAAs, perfluoroalkyl acids.High Resolution ImageDownload MS PowerPoint SlideTotal Fluorine ScreeningClick to copy section linkSection link copied!Screening for total fluorine (TF) provides a relatively fast and inexpensive way to assess whether PFAS may be present in a sample. A key feature of TF screening (and in contrast to extractable or adsorbable organic fluorine) is that samples are not extracted prior to analysis, making sample preparation relatively easy and allowing all PFAS to be indirectly quantified. Examples of such techniques include combustion ion chromatography (CIC) and particle-induced γ-ray emission (PIGE) spectroscopy. (2) Additional TF methods [e.g., instrumental neutron activation analysis (INAA), X-ray photoelectron spectroscopy (XPS), and 19F nuclear magnetic resonance (NMR)] may also be suitable for compliance testing if they demonstrate performance across a range of matrices. The most important consideration for these methods is whether their detection limits comply with the limit values defined in the relevant regulation. Fluorine detection limits of <30% of the restriction limit value (where applicable) and a measurement uncertainty of 50% on a weight basis of the material may be reasonable criteria for successfully applying these methods as part of compliance testing. Because some methods measure bulk material concentrations (e.g., CIC) while others measure surface concentrations (e.g., PIGE), the choice of a specific technique for screening may depend on several factors, including product homogeneity and whether the limit value is defined on a mass or area basis.Confirmation of CF2 or CF3 MoietiesClick to copy section linkSection link copied!Because TF methods may be subject to false positives from inorganic fluorine or non-PFAS organofluorines, further information may be needed for products that can contain other fluorine sources besides PFAS. For example, under the proposed REACH restriction, if screening finds that the level of a product exceeds 50 ppm TF, the manufacturer, importer, or downstream user is obligated to provide proof that the measured TF originates from inorganic or non-PFAS organofluorine. The most pragmatic approach for addressing this requirement is to directly consult the supplier and obtain disclosure of any PFAS. If reliable information is not available, the presence or absence of CF2 or CF3 groups may be determined analytically. A suitable method does not necessarily need to deduce the exact chemical structure but should be suitable for robustly detecting CF2 or CF3 groups across a wide range of PFAS and products at detection limits that are ideally <30% of the restriction limit value. Importantly, the method should not require pretreatment steps (e.g., extraction), which could introduce bias, (3) and CF2 or CF3 groups should not be produced as analytical artifacts during the analysis. Examples of methods that may be suitable for this purpose include pyrolysis-gas chromatography-mass spectrometry (pyr-GCMS) and 19F NMR, (4,5) but considerable work is still required to validate these approaches for application in a regulatory context. For pyr-GCMS, users should also be aware of the potential for false positives from substances containing CF2 or CF3 groups that either do not meet the formal PFAS definition or are excluded from a restriction (see examples in ref (6)). The 19F NMR technique is currently predominantly available for liquid samples, and further research is needed for solid state applications.Quantifying Individual PFAS or the Sum of PFASClick to copy section linkSection link copied!Some restrictions include limit values for individual PFAS or the sum of PFAS (ΣPFAS) that are often several orders of magnitude lower than the detection limits of TF methods, requiring more specific analytical approaches. For example, the REACH restriction proposal includes a 25 ppb limit for individual PFAS (excluding polymers) and a 250 ppb limit for ΣPFAS measured by target analysis optionally following transformation of precursors. The rationale for these comparatively low values is that low-molecular weight PFAS often occur as impurities in products containing polymeric PFAS. Additionally, there may be cases in which low-molecular weight PFAS are intentionally added at levels close to or even below TF limit values. (7)To address limits associated with individual PFAS or ΣPFAS, we recommend (at a minimum) measurement of C2–C16 perfluoroalkyl carboxylic acids (PFCAs) and C1–C10 perfluoroalkyl sulfonic acids (PFSAs) after the transformation of their precursors. The proposed range is based on the prevalence of these perfluoroalkyl acid (PFAA) homologues and their precursors in the environment. Methods for the transformation of PFAA precursors to PFAAs include the total oxidizable precursors (TOP) and photoTOP methods, which should be directly and quantitatively applied to the product, rather than the extracts. (3) Moreover, in cases in which individual or ΣPFAS limits are stipulated without precursor transformation, additional analyses should be performed without TOP or photoTOP.These methods may be supplemented with additional target substances (e.g., non-PFCA-forming PFAS such as perfluoroether carboxylic acids). The choice of targets could be based on supply chain information or prior knowledge, e.g., from technical literature on product uses and ingredients. When no prior information is available, liquid chromatography (LC)- and GC-based nontarget analytical techniques, in particular those suitable for flagging PFAS, (8,9) may also prove useful. Here, ionization efficiency approaches offer an opportunity for quantification in the absence of standards, (10) but the efficacy and acceptance of these approaches in a regulatory context remain unclear.OutlookClick to copy section linkSection link copied!The workflow in Figure 1 illustrates how the methods described above could be used by manufacturers and importers or by relevant authorities to assess compliance with the proposed classwide restrictions on PFAS under REACH. Because a full characterization of all commercially available PFAS, their impurities, and their degradation products is not practically feasible, the workflow does not offer verification of a compliant product. The workflow is rather designed to efficiently identify noncompliant products using a tiered approach. As methods are developed and refined for different product categories, it is conceivable that some steps may be modified or combined to save costs and improve throughput. Other regulatory frameworks besides REACH may require only part of this workflow to assess compliance, depending on their scope.As more jurisdictions enact PFAS-related bans, the demand for the methods discussed here will increase. However, most of these methods are currently not commercially available. We recommend that analytical laboratories focus on further developing these methods to support compliance with these new and emerging regulations around the world. To be generally accepted for compliance, the methods must be validated and standardized and demonstrate high accuracy, precision, specificity, and robustness and sufficiently low detection limits. Timely action to validate and standardize these methods will help facilitate implementation of classwide PFAS restrictions globally and ultimately pave the way for more efficient group management of chemicals in the future.Author InformationClick to copy section linkSection link copied!Corresponding AuthorsRobin Vestergren - Swedish Chemicals Agency (KEMI), 17266 Stockholm, Sweden; Email: [email protected]Jonathan P. Benskin - Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden; https://orcid.org/0000-0001-5940-637X; Email: [email protected]AuthorsAnders Appelblom - Swedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenSimona A. Bălan - California Department of Toxic Substances Control, Berkeley, California 94710, United States; https://orcid.org/0000-0003-0438-1616Sicco H. Brandsma - Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The NetherlandsThomas A. Bruton - California Department of Toxic Substances Control, Sacramento, California 95814, United States; https://orcid.org/0000-0002-4090-6021Ian T. Cousins - Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden; https://orcid.org/0000-0002-7035-8660Jeremy R. Gauthier - Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada; https://orcid.org/0000-0002-6446-706XAudun Heggelund - Norwegian Environment Agency, Box 5672, Torgarden, N-7485 Trondheim, Norway; https://orcid.org/0009-0003-6900-0316Jenny Ivarsson - Swedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenAnna Kärrman - School of Science and Technology, Örebro University, 70182 Örebro, SwedenLisa Melymuk - RECETOX, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic; https://orcid.org/0000-0001-6042-7688Chijioke Olisah - RECETOX, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic; https://orcid.org/0000-0002-7714-3056Amanda Rosen - Swedish Chemicals Agency (KEMI), 17266 Stockholm, SwedenEleni K. Savvidou - Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden; https://orcid.org/0009-0001-0662-6202Steffen Schellenberger - RISE Research Institutes of Sweden AB, Environment and Sustainable Chemistry Unit, 11428 Stockholm, Sweden; https://orcid.org/0000-0001-8001-6851Lisa Skedung - RISE Research Institutes of Sweden AB, Department Materials and Surface Design, 11428 Stockholm, Sweden; https://orcid.org/0000-0001-6657-1592Petteri Talasniemi - Finnish Safety and Chemicals Agency (Tukes), Box 66, 00521 Helsinki, FinlandTonie Wickman - RISE Research Institutes of Sweden AB, The Swedish Centre for Chemical Substitution, 11428 Stockholm, SwedenJonathan Zweigle - Environmental Analytical Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany; https://orcid.org/0000-0002-7194-1567Christian Zwiener - Environmental Analytical Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany; https://orcid.org/0000-0002-6682-5828NotesThe authors declare no competing financial interest.BiographiesClick to copy section linkSection link copied!Robin VestergrenHigh Resolution ImageDownload MS PowerPoint SlideDr. Robin Vestergren is currently a Scientific Officer in the Swedish Chemicals Agency. He received his Ph.D. from Stockholm University in 2011 after which he worked as a postdoctoral fellow at the Norwegian Institute for Air Research (NILU), Norway, and the Research Center for Eco- and Environmental Sciences (RCEES), Beijing, China. During his time as a researcher, he made substantial contributions to understanding the fate and exposure of per- and polyfluoroalkyl substances (PFAS). His current work focuses on how to improve the regulatory uptake of science to support the risk assessment and risk management of chemicals.Jonathan P. BenskinHigh Resolution ImageDownload MS PowerPoint SlideJonathan Benskin is a Professor in the Department of Environmental Science at Stockholm University (SU). His research focuses on the development and application of novel analytical tools for uncovering emerging pollutants in the environment, with a particular emphasis on organohalogen mass balance experiments and high-resolution mass spectrometry-based nontarget screening. Prior to joining SU in 2014, he completed a Ph.D. in medical sciences (University of Alberta, 2011) and held positions as a Principal Scientist and NSERC Industrial Research and Development Fellow (both at AXYS Analytical) and a Visiting Scientist (Fisheries and Oceans Canada Institute of Ocean Sciences).AcknowledgmentsClick to copy section linkSection link copied!This work was carried out in the framework of the European Partnership for the Assessment of Risks from Chemicals (PARC) and has received funding from the European Union's Horizon Europe research and innovation programme under Grant Agreement 101057014. L.M. and C.O. were co-funded by the Czech Ministry of Education, Youth and Sports from the Institutional Support of LCDRO and RECETOX Research Infrastructure (LM2023069). The contribution by RISE employees (S.S., L.S., and T.W.) was co-funded by the Swedish Ministry of Climate and Enterprise. E.K.S. and I.T.C. thank the Swedish Research Council FORMAS (Grant 2020-01978) and the Horizon 2020 research and innovation programme (Grant Agreement 101036756; the ZeroPM project) for funding. Views and opinions expressed are those of the authors only and do not necessarily reflect those of the European Union or the Health and Digital Executive Agency, nor those of the Swedish Chemicals Agency, the Finnish Safety and Chemicals Agency, the Norwegian Environment Agency, or the California Department of Toxic Substances Control or California government. Neither the European Union, the Swedish Chemicals Agency, the Finnish Safety and Chemicals Agency, the Norwegian Environment Agency, the California Department of Toxic Substances Control, State of California, nor the granting authorities can be held responsible for them.ReferencesClick to copy section linkSection link copied! This article references 10 other publications. 1ECHA 2023. Annex XV Restriction Report - Proposal for a Restriction of Per- and polyfluoroalkyl substances (PFASs). https://echa.europa.eu/fi/registry-of-restriction-intentions/-/dislist/details/0b0236e18663449b (accessed 2024-06-29).Google ScholarThere is no corresponding record for this reference.2Schultes, L.; Peaslee, G. F.; Brockman, J. D.; Majumdar, A.; McGuinness, S. R.; Wilkinson, J. T.; Sandblom, O.; Ngwenyama, R. A.; Benskin, J. P. Total Fluorine Measurements in Food Packaging: How Do Current Methods Perform?. Environ. Sci. Technol. Lett. 2019, 6 (2), 73– 78, DOI: 10.1021/acs.estlett.8b00700 Google Scholar2Total fluorine measurements in food packaging: How do current methods perform?Schultes, Lara; Peaslee, Graham F.; Brockman, John D.; Majumdar, Ashabari; McGuinness, Sean R.; Wilkinson, John T.; Sandblom, Oskar; Ngwenyama, Ruth A.; Benskin, Jonathan P.Environmental Science & Technology Letters (2019), 6 (2), 73-78CODEN: ESTLCU; ISSN:2328-8930. (American Chemical Society) Per- and polyfluoroalkyl substances (PFASs) represent a class of more than 4000 compds. Their large no. and structural diversity pose a considerable challenge to anal. chemists. Measurement of total fluorine in environmental samples and consumer products is therefore crit. for rapidly screening for PFASs and for assessing the fraction of unexplained fluorine(i.e., fluorine mass balance). Here we compare three emerging anal. techniques for total fluorine detn.: combustion ion chromatog. (CIC), particle-induced γ-ray emission spectroscopy (PIGE), and instrumental neutron activation anal. (INAA). Application of each method to a certified ref. material (CRM), spiked filters, and representative food packaging samples revealed good accuracy and precision. INAA and PIGE had the advantage of being nondestructive, while CIC displayed the lowest detection limits. Inconsistencies between the methods arose due to the high aluminum content in the CRM, which precluded its anal. by INAA, and sample heterogeneity (i.e., coating on the surface of the material), which resulted in higher values from the surface measurement technique PIGE compared to the values from the bulk vol. techniques INAA and CIC. Comparing CIC-based extractable org. fluorine to target PFAS measurements of food packaging samples by liq. chromatog.-tandem mass spectrometry revealed large amts. of unidentified org. fluorine not captured by compd.-specific anal. >> More from SciFinder ®https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXit1Wjt7s%253D&md5=118fda7ea0b274f170a18960146569213Zweigle, J.; Capitain, C.; Simon, F.; Roesch, P.; Bugsel, B.; Zwiener, C. Non-Extractable PFAS in Functional Textiles: Characterization by Complementary Methods─Oxidation, Hydrolysis, and Fluorine Sum Parameters. Environ. Sci.: Processes Impacts 2023, 25 (8), 1298– 1310, DOI: 10.1039/D3EM00131H Google ScholarThere is no corresponding record for this reference.4Skedung, L.; Savvidou, E.; Schellenberger, S.; Reimann, A.; Cousins, I. T.; Benskin, J. P. Identification and quantification of fluorinated polymers in consumer products by combustion ion chromatography and pyrolysis-gas chromatograp

To date, considerable knowledge and data gaps regarding the occurrence, environmental levels, and fate of polymeric perfluoroalkyl and polyfluoroalkyl substances (PFAS) exist. In the present study availability, accumulation, and transformation of C4- and C8-fluoroalkylsulfonamide (FASA)-based copolymers were assessed in laboratory-grown earthworms (Eisenia fetida, triplicate of exposure tests and control). Further, a field study on earthworms (18 pooled samples) in sludge-amended soil was conducted to assess the environmental impact of sludge-amended soil with regard to the FASA-based copolymers, together with the applied sludge (n = 3), and the field soils during the period (n = 4). In the laboratory study, the FASA-based copolymers were taken up by the earthworms in concentrations between 19 and 33 ng/g of dw for the C8- and between 767 and 1735 ng/g of dw for the C4-FASA-based copolymer. Higher biota soil accumulation factors (BAFs) were observed for the copolymer with a longer perfluorinated side-chain length (C8, average BAF value of 0.7) compared to the copolymer with a shorter side-chain length (C4, average BAF value of 0.02). Perfluorooctane sulfonamidoacetates (FOSAAs) and perfluorooctane sulfonamide (FOSA), including both branched and linear isomers, were detected after exposure to the C8-FASA-based copolymer. Two metabolites were detected in the earthworms exposed to the C4-FASA-based copolymer: perfluorobutanesulfonamide (FBSA) and perfluorobutanesulfonic acid (PFBS). Although the presence of other monomers or impurities in the copolymer formulation cannot be ruled out, the present laboratory study suggests that the FASA-based copolymers may be an indirect source of lower molecular weight PFAS in the environment through transformation. Elevated levels of C8-FASA-based copolymer were found in the field sludge-amended soil compared to nontreated soil (32 versus 11 ng/g d.w.), and higher concentrations of PFAS in earthworms living in sludge-amended soil compared to nontreated soil (566 versus 103 ng/g d.w.) were observed. These findings imply that the application of sludge is a potential pathway of PFAS to the environment.