The environmental persistence of Per- and polyfluoroalkyl substances (PFAS) results in prolonged exposure of organisms, which in turn leads to bioaccumulation and trophic transfer. However, if trophic transfer is studied at all, different ecosystems are generally examined in isolation. The aim of this study was therefore to unravel the PFAS transfer through a contaminated terrestrial and aquatic food web, with spiders as top predators. To this end, organisms from the aquatic and terrestrial compartments of a PFAS-contaminated ecosystem were collected and screened for 44 PFAS. The trophic position of the organisms was investigated using stable isotopes. PFAS were present in organisms from all trophic levels (primary producers, herbivores, detritivores, predators), albeit with varying total concentrations and profiles. Several PFAS magnified towards the spiders through the terrestrial food web, adding to the growing body of evidence that some PFAS have the potential to magnify, while trophic transfer was less pronounced through the aquatic food web. There was no consistent pattern in which substances magnified and which got diluted across the food chain. TFA, the smallest and most polar PFAS, showed high food chain transfer. This emphasizes that we still lack insight into the drivers of environmental PFAS distribution, uptake by organisms and transfer through food webs.

The extensive production and use of per- and polyfluoroalkyl substances (PFAS) over recent decades have resulted in their pervasive distribution in environmental compartments worldwide. PFAS concentrations in soil and biota near fluorochemical manufacturing facilities tend to be typically higher near hotspots, which suggests that the consumption of home-produced foods near such hotspots most likely results in higher human exposure. One prominent European hotspot is located near the 3M fluorochemical production facility in Zwijndrecht (Belgium), where the relative contributions of different exposure pathways remain insufficiently characterised. This study therefore aimed to assess the PFAS concentrations and compositional profiles in serum, dwellings and gardens of teenagers residing near this hotspot. Serum samples from teenagers, along with multiple environmental matrices (i.e., soil, compost, vegetables/fruits/nuts, chicken eggs, rainwater and indoor house dust) were analysed for 21 selected PFAS. Additionally, potential determinants of PFAS occurrence and distribution across matrices were investigated using detailed questionnaire data. We found perfluorooctane sulfonic acid (PFOS) to be the predominant compound in both soil and serum, while perfluorobutanoic acid (PFBA) was most dominant in rainwater, compost, house dust and pods. Perfluorobutane sulfonic acid (PFBS) was most abundant in fruits and chicken eggs, while perfluorododecanoic acid (PFDoDA) was predominant in rooting vegetables and nuts. N-methylperfluorooctane sulfonamidoacetic acid (MePFOSAA) was the dominant compound in fruiting, stem, and leafy vegetables. These results indicate differences in accumulation pathways among the different media and/or differences in affinities of different PFAS in the matrices. Additionally, several environmental and behavioural factors were identified as determinants for PFAS in soil, compost, tree fruits, fruiting vegetables, chicken eggs and house dust, providing insight into potential drivers of exposure variability. The most important factors were related to the soil characteristics, the composting of grass and weeds, the chicken feed (i.e., bread, commercial feed), the type and frequency of ventilation and the frequency of cleaning.

Per- and polyfluoroalkyl substances (PFAS) are widespread in our environment, and have the ability to bioaccumulate in biota. To monitor local PFAS contamination, often bioindicator species are used, of which the great tit is a frequently studied species. To be able to monitor these compounds, generally invasive sampling techniques are used (e.g. blood plasma, feathers). To this day, only a few studies have analysed PFAS in the faeces of wild birds, which were all performed on aquatic birds, and only one of these looked at the suitability of faeces samples to replace blood sampling. Therefore, the present study looked at the PFAS concentrations and compositional profiles in blood plasma, feathers and faeces of great tits and associations between these matrices, to provide novel and important information on non-invasive monitoring practises. All samples were analysed for 42 target PFAS using UPLC-MS/MS analysis. Matrix-specific differences were found in PFAS accumulation among blood plasma, feathers and faeces. Most compositional profiles were dominated by long-chained PFSAs, of which PFOS was the dominant compound, both in adults and nestlings. Furthermore, diPAPs were only detected in feather samples. Additionally, only very few associations were found among the matrices analysed, which suggests that faecal samples are not suitable to replace plasma or feather samples. On the other hand, faecal samples were proven to give valuable complementary information on the exposure of these birds to PFAS.

Short-chain per- and polyfluorinated substances (PFAS) are widely distributed in the environment, but their chronic effects on soil organisms exposed over multiple generations remain largely unknown. The present study therefore aimed to investigate the toxicity of perfluorobutane sulfonic acid (PFBS) and its precursor perfluorobutane sulfonamide (FBSA) to the springtail Folsomia candida during five successive generations with the following endpoints: the median lethal concentration (LC50) for adult survival and the median effect concentration (EC50) for reproduction (EC50_repro) and population growth rate (EC50_r). The LC50 and EC50_r of PFBS were above the highest test concentration (1,300 mg/kg dry soil) for all generations, while the EC50_repro was 1,260 and 762 mg/kg dry soil in F2 and F4 (i.e., third and fifth generations), respectively, although the difference was not significant owing to wide 95% confidence intervals. In contrast, FBSA exhibited significant reproductive toxicity and thereby affected the population growth rate, with LC50, EC50_repro, and EC50_r values of 10.3, 1.14, and 1.67 mg/kg dry soil in F0. The extinction of the populations exposed to the two highest FBSA concentrations (8.85 and 88.3 mg/kg dry soil) in F0 hindered toxicity assessment in subsequent generations, with only an EC50_repro of 0.965 mg/kg dry soil determined in F1. Although the effect concentrations were above environmental levels, the more pronounced reproductive toxicity made FBSA >1,140 and >1,350 times more toxic to F. candida reproduction than PFBS in F0 and F1. These findings reveal that understudied PFAS may pose hidden risks, thus emphasizing the need to expand the currently limited spectrum of PFAS considered in environmental risk assessment. This study also highlights the value of long-term hazard assessment of PFAS in multigeneration scenarios, which could better capture the potential risks posed by these very persistent chemicals.

Per- and polyfluoroalkyl substances (PFASs) are widely used, with significant environmental and health impacts. PFASs often exist as isomers with distinct physicochemical properties that influence their environmental fate and toxicity. This study advances PFAS analysis through isomeric resolution of 41 linear and 39 branched congeners by liquid chromatography-ion mobility-high-resolution mass spectrometry (LC-IM-HRMS), reporting the largest collision cross-section (CCS) data set for PFAS structural isomers to date, including the first reported drift-tube ion mobility (DTIM)-derived DTCCSN2 values for PFNA and PFNS isomers. The workflow was successfully applied to 41 great and blue tit egg samples collected near a contaminated industrial site in Belgium, where 20 linear and 34 branched PFAS isomer features were detected. Correlation analysis between the number of isomers detected for each PFAS in bird eggs revealed distinct co-occurrence patterns among branched PFAS isomers, with PFBS and PFDoDA showing unique behavior compared with other PFAS classes. A significant difference in PFOS isomer profiles was identified between the two species, which may be related to differences in foraging behavior and species-specific accumulation. The results demonstrate that LC-IM-HRMS is a useful tool for confidence-enhanced PFAS isomer identification in complex biological samples despite the limited availability of single-branched isomer standards and highlight the value of isomer-resolved analysis for environmental biomonitoring and exposure characterization.

Fluorochemical production (FCP) sites are key hotspots for per- and polyfluoroalkyl substances (PFAS), persistently contaminating nearby soils. Most studies on FCP-impacted environments have relied on targeted analyses, which may overlook emerging and unknown PFAS, such as precursors that can transform into stable products. To address this gap, an integrated analytical workflow combining the direct total oxidizable precursor (dTOP) assay with high-resolution mass spectrometry (HRMS)-based suspect and non-target screening (SS/NTS) was performed on PFAS-contaminated soils collected at and near an FCP site in Flanders, Belgium. The dTOP assay conditions was optimized through Design of Experiment, which identified relative quantities of sodium hydroxide and potassium persulfate as significant factors (p < 0.01), along with temperature and reaction time, applicable in both moderately and highly contaminated soils (oxidation efficiency > 99.3%). SS/NTS of post-dTOP samples also showed efficient oxidation of emerging PFAS classes (e.g., 95% oxidation of pentafluorosulfide perfluoroalkyl sulfonic acid), but also revealed increases in emerging non-target PFAS (NT-PFAS), which are oxidation products of other precursors. This study enabled the examination of the behavior of several NT-PFAS and the estimation of PFAS precursors.

Coastal wetlands are increasingly exposed to multiple pollutants, including metal and per- and polyfluoroalkyl substances (PFAS). However, metal and PFAS co-occurrence and interactions in mangrove sediments remain poorly understood. This study provides one of the first investigations of metal and PFAS co-distribution in mangrove sediment cores across two contrasting tropical estuarine systems and between old and young mangrove forest sites. No vertical stratification of contaminants was observed, likely due to intense bioturbation. Distinct spatial trends emerged between and within estuaries, reflecting differences in local sources, salinity-driven partitioning, and dilution downstream. Sediments near urbanized areas generally contained higher concentrations of metals and PFAS. Mangrove age influenced contaminant levels, possibly through differences in sediment accretion and hydrological conditions, though these effects were spatially variable. Sediment texture and organic carbon content were relatively uniform, yielding few and generally weak correlations with contaminant concentrations. Significant associations between metals and PFAS suggest co-distribution mechanisms influenced by shared geochemical factors. While metal concentrations indicated moderate contamination and overall limited ecological risk, PFAS levels often exceeded those reported for heavily impacted estuarine systems. These findings highlight the need for source control, long-term monitoring, and multidisciplinary studies integrating hydrology, geochemistry, and ecotoxicology to protect the resilience of mangrove ecosystems facing intensifying anthropogenic pressures.

Per- and polyfluoroalkyl substances (PFAS) are global pollutants, yet data from tropical freshwater ecosystems remain scarce. This study provides the first assessment of PFAS occurrence in the Rusizi delta (Burundi), from tributaries to Lake Tanganyika, by analyzing water, sediment, macrophytes, and fish, and by evaluating human health risks from fish consumption. In water, only PFOA (<0.60-7.80 ng/L) was detected and showed a uniform spatial distribution. Sediment concentrations were largely below quantification limits, likely reflecting unfavorable sorption conditions. Macrophytes were dominated by short-chain PFAS, particularly PFBS, without consistent species- or site-specific patterns, supporting their potential as biomonitors of cumulative PFAS exposure. Fish exhibited the highest PFAS diversity, with more diverse profiles in liver than muscle, although tissue-specific patterns were often absent. PFBS was dominant across fish species, and emerging PFAS (e.g., PFBS and NaDONA) were frequently detected. Human health risks from fish consumption were, except for children, mostly below EFSA tolerable weekly intake values for regulated PFAS, but potential concern for adolescents and adults emerged when PFAS were expressed as PFOA equivalents. This study provides essential baseline data for tropical freshwater systems and highlights the need for expanded PFAS monitoring and risk assessment in data-poor regions.

Per- and polyfluoroalkyl substances (PFAS) are persistent and bioaccumulative contaminants of emerging concern in aquatic ecosystems, yet their uptake dynamics and physiological effects on macrophytes remain poorly understood. This study investigated PFAS bioaccumulation and physiological responses of Lemna minor exposed to seven PFAS compounds under both acute and chronic conditions. Longer exposure durations resulted in detectable accumulation of a greater number of PFAS, particularly at lower exposure concentrations. Concentration-dependent accumulation was observed, although the direction and magnitude of these relationships varied among PFAS types. PFBS showed the highest accumulation, with concentrations up to 8736 ± 5715 ng/g dw detected after 10 days of exposure to 100,000 ng/L. When expressed as bioconcentration factors (BCFs), an inverse relationship with exposure concentration indicated higher uptake efficiency at environmentally relevant concentrations. The highest BCF (6076 ± 898 L/g) was observed for PFBS after 20 days of exposure to 1 ng/L. Differences in accumulation and BCF values were attributed to functional group and chain length, which affect solubility and hydrophobicity. Despite measurable bioaccumulation, physiological responses were generally minor, as neither growth nor photosynthetic efficiency (Fv/Fm and Y(II)) showed consistent impairment. Growth stimulation was observed in a limited number of treatments, suggesting potential hormetic effects. Overall, these findings highlight that both exposure duration and concentration range should be considered when assessing PFAS bioaccumulation in macrophytes, and that integrating time-dependent accumulation into risk assessments is essential for accurately evaluating PFAS behaviour and ecological risks.

Per- and polyfluoroalkylated substances (PFAS) are widely distributed, and although PFAS may be deleterious to marine organisms, there is a lack of studies in the southern hemisphere. The presence of 29 PFAS in marine invertebrates and fish from Antarctica (Fildes Bay), Patagonia (La Leona Island, Marchant River Mouth), and northern Chile (Pan de Azucar Bay) were studied here. Samples were collected during the austral summer (January-February 2015) and analyzed by Ultra-performance liquid chromatography-tandem ES (-) mass spectrometry. ∑PFAS ranged from 3.03 ng/g dw (dry weight) in Austral red starfish (Odontaster validus) to 120.3 ± 33.7 ng/g dw in red cusk-eel (Genypterus chilensis). The results showed local contamination and underscores the far-reaching impact of anthropogenic pollutants. Due to the potential health consequences of PFAS exposure it requires having effective regulatory measures to avoid these chemically synthesized substances ending up in remote regions of the southern hemisphere where they could bioaccumulate. The data can serve as a base for further research to understand the full extent of PFAS contamination and its implications for remote ecosystems.

This study investigated the distribution of 29 legacy and emerging per- and polyfluoroalkyl substances (PFASs) in soil, nettles, invertebrates, and plasma and feathers of great tits (Parus major) of a terrestrial ecosystem near a fluorochemical plant. Additionally, the vertical distribution of PFASs in soil was assessed, as well as taxon-specific differences among terrestrial invertebrate species. Finally, associations between soil and biota, and among biological matrices, were assessed. Most accumulation profiles were dominated by long-chained PFASs, mainly perfluorooctane sulfonic acid (PFOS), while short-chained PFASs were less detected. Long-chained perfluoroalkyl carboxylic acids (PFCAs) adsorbed in the upper soil layers, while short-chained PFAS and perfluoroalkyl sulfonic acids (PFSAs) tended to migrate deeper. The several taxon-specific differences were likely due to dietary differences. Significant associations, especially for long-chained PFCAs and PFOS, were found among most matrices. This indicates that (1) these PFASs found in these matrices are most likely originating from the same pollution source, (2) there is a possible transfer of these PFASs between matrices, (3) there is bioaccumulation from one to another matrix, and (4) some matrices might be used as proxies to estimate PFAS concentrations in other terrestrial matrices. Finally, feathers accumulated more PFASs than plasma, as they were most likely exposed through different routes of exposure and PFAS affinity. Therefore, they are not suitable for internal PFAS monitoring but can provide complementary information about the exposure and about the presence/absence of PFASs in certain habitats.

The Flanders region (Belgium) has several per- and polyfluoroalkyl substances (PFAS) hotspots due to industrial activities, including a fluorochemical plant (FCP) near Antwerp. Previous studies in this area reported exceptionally high levels of legacy PFAS in soils, invertebrates and birds using targeted liquid chromatography-mass spectrometry (LC-MS/MS) methods. In this study, bird eggs were used as biomonitoring tools to comprehensively investigate PFAS bioaccumulation near the hotspot through suspect and non-target high-resolution mass spectrometry (HRMS) screening. A total of 40 eggs (26 Great tit Parus major, 14 Blue tit Cyanistes caeruleus) were collected from three sites near the FCP during the 2022 breeding season. Suspect screening was based on two PFAS lists covering over 10,000 compounds, and non-targeted analysis using the FluoroMatch software. In addition to target PFAS, 62 compounds spanning 16 classes were identified and assigned Confidence Levels 2 or 3. Semi-quantification revealed notably high levels of emerging PFAS, particularly homologues of ether-substituted perfluoroalkyl sulfonic acids (PFESAs) and pentafluorosulfide perfluoroalkyl sulfonic acids (SF5-PFSAs), including the first detection of SF5-PFSA C6 in biota. Quantification and semi-quantification showed the highest levels of some PFAS ever measured in bird eggs, with compounds identified by HRMS contributing up to 15% of the total PFAS burden. This is the first study to report such a broad and highly concentrated profile of emerging, largely non-oxidizable PFAS in bird eggs, underscoring the importance of suspect and non-targeted analysis. These rarely monitored PFAS should be considered for inclusion in both human and environmental monitoring programmes and risk assessments.

Intertidal wetlands are increasingly threatened by pollutants such as per- and polyfluoroalkyl substances (PFAS), yet their role in PFAS retention and distribution remains underexplored. This study investigated PFAS accumulation in sediments from an old natural and a recently restored intertidal wetland, examining how eco-geomorphology, sediment characteristics, and distance from the estuarine main channel may affect PFAS fate. This study is one of the first to assess the impact of tidal re-introduction on PFAS contamination in a restored wetland. Both legacy and emerging PFAS were detected, with PFBS and 6:2 FTS dominating the profiles. Tidal restoration significantly increased PFAS accumulation, supporting the potential of wetland restoration as a nature-based solution for PFAS removal: concentrations of PFOS, PFOA, and PFBS rose by 12x, 3x, and 5x, respectively, and more types of PFAS were observed. This study provides the first field-based indication that eco-geomorphology - particularly vegetation, surface elevation, and related flow attenuation and enhanced sediment deposition - plays an important role in shaping the spatial distribution of PFAS in intertidal wetlands. Sediment characteristics and proximity to the main estuarine channel played lesser roles. Our findings show that tidal marshes act as both sinks and potential filters for PFAS, highlighting the dual role of wetlands in long-term contaminant storage and phytoremediation, with important implications for estuarine PFAS dynamics and management. Continued monitoring and site-specific risk assessments are essential to ensure long-term functionality and safeguard ecosystem and human health.

The widespread use and persistence of per- and polyfluoroalkyl substances (PFAS) have raised concerns about their ecological impacts. The relative lack of toxicological data for most current-use PFAS, including short-chain compounds such as perfluorobutane sulfonate (PFBS) and precursors such as perfluorobutane sulfonamide (FBSA), is an uncertainty factor in ecological risk assessment. This study investigated the bioaccumulation and chronic toxicity (mortality, light avoidance, and change in soil granulometry as proxy of burrowing behaviour) of PFBS and FBSA in the earthworm species Eisenia fetida and Eisenia andrei in the natural standard LUFA 2.2 soil. Results showed that FBSA was more bioaccumulative (biota-to-soil accumulation factor (BSAF, minimum - maximum) of 0.191-205 kg-OC/kg-ww) and toxic than PFBS, with significant mortality (28-day LC50 10.0-10.4 mg/kg dry soil) and impaired light avoidance behaviour observed at concentrations close to the 28-day LC50 concentration. PFBS exhibited a lower bioaccumulation potential (minimum - maximum BSAF of 3.85*10-5 - 7.44 kg-OC/kg-ww) and toxicity (28-day LC50 > 1000 mg/kg dry soil). For both PFAS, BSAF values were strongly dependent on exposure concentrations, with the highest BSAF values reported at the lower, environmentally relevant, test concentrations. Species-specific differences in bioaccumulation (absolute concentrations and BSAF values) were minor, with E. andrei showing slightly higher PFBS accumulation (4.13 ± 0.979 mg/kg ww) at high (1000 mg/kg dry soil) exposure concentrations than E. fetida (2.34 ± 0.0633 mg/kg ww). Despite minor differences in soil granulometry changes among exposure treatments, no clear dose-dependent patterns nor species-specific differences were observed. Overall, our results show a high bioaccumulation potential, but low toxicity, of FBSA and PFBS at environmentally relevant concentrations.

There is an imbalance in the current discussion around the environmental impact of total intravenous anaesthesia (TIVA) versus volatile anaesthetics. The discourse often leans heavily towards scrutinising the greenhouse gas emissions linked to volatile anaesthetics. Although propofol has a much smaller impact on global warming compared to volatile anaesthetics, some argue it may not be a suitable alternative for maintaining anaesthesia due to concerns about its potential ecotoxic effects on aquatic life. This review focuses on the ecotoxicity of propofol, remediation techniques, pharmaceutical waste management and the greenhouse gas emission linked to propofol.

Exposure to per- and polyfluoroalkyl substances (PFAS) and how to reduce exposure is worldwide debated, leads to new regulations and advice for food consumption. PFAS are a complex class of chemicals. These so-called ‘forever chemicals’ are ubiquitous in the environment and consumer products, enter the food chain, and are detected in human bodies worldwide. Human PFAS serum concentrations are associated with dietary intake of certain foods. Seafood and offal consumption, packaged and wrapped foods, and food grown in contaminated areas are often associated with higher serum PFAS levels, while the reverse holds for more plant-based and more fibers containing diets. In contaminated areas, consumption of some local foods should be discouraged. However, for effective reduction of human exposure through food, more information is needed on sources and transfer of PFAS into agricultural products and processed foods, not only for legacy PFAS but also for short-chain PFAS and their precursors.

Targeted analysis of per- and polyfluoroalkyl substances (PFAS) relies on a limited number of reference standards, and consequently, many PFAS remain unidentified, which restricts comprehensive monitoring and risk assessment. Here, we apply high-resolution mass spectrometry (HRMS)-based suspect and nontarget screening (SS/NTS), alongside targeted analysis, to detect and (semi)quantify legacy, emerging, and novel PFAS in soils near a PFAS hotspot in Flanders, Belgium. Targeted analysis quantified 36 PFAS, with perfluorooctanesulfonic acid (PFOS) as the most predominant, alongside precursors such as ethyl perfluorooctane sulfonamido acetic acid (Et-FOSAA) and perfluorooctane sulfonamide (FOSA). On the other hand, SS/NTS identified over 100 PFAS homologues and isomers, including pentafluorosulfide sulfonic acids (SF5-PFSAs), perfluorophosphinic acids (PFPiAs), and perfluorophosphoric diesters (PFPDEs). Total PFAS concentrations at the 3M site varied widely, reaching 118.5 μg/g, among the highest reported globally. These findings highlight the complexity of PFAS contamination in the study area and the need for site-specific analyses to support monitoring, source tracking, regulation, and risk assessment.

Per- and polyfluoroalkyl substances (PFAS) are a concern due to their persistence and widespread environmental distribution. This study analysed PFAS in water, sediment, and bivalves (resident blue mussels and translocated Asian clams) along the Scheldt Estuary (the Netherlands-Belgium) using target, suspect screening (SS), and non-target analysis (NTA). As a result, various PFAS, including ultra-short-, short-, and long-chain PFAS, were detected in varying concentrations. Targeted analysis detected 8 PFAS in water (∑PFAS: 9.4-585 ng/L), 11 PFAS in sediment (∑PFAS: 7.5-47.8 ng/g dw), and 8 PFAS in bivalves (∑PFAS: 1.8-17.5 ng/g ww). SS and NTA detected 7 to 9 additional PFAS in each matrix, with estimated ∑PFAS concentrations ranging from 883 to 6421 ng/L in water, 49 to 110 ng/g dw in sediment, and 42 to 111 ng/g ww in bivalves. Short-chain PFAS dominated the relative contributions to ∑concentrations in each matrix. The Environmental Quality Standard (EQS) for perfluorooctanesulfonate (PFOS) in surface water (0.65 ng/L) was exceeded at most locations, while in bivalves it remained below the biota EQS of 9.1 ng/g ww at all sites. Estimated ∑PFAS concentrations based on SS and NTA generally exceeded results from targeted analysis in each matrix, emphasizing the importance of untargeted methods for comprehensive PFAS monitoring and risk assessments. Notably, trifluoromethanesulfonic acid (TFMS) dominated at an industrial estuary reach, while several precursors were tentatively annotated. Multivariate analyses indicated inverse correlations between bivalve-sediment ∑PFAS and positive sediment PFAS correlations with TOC and clay, indicating sorption-limited bioavailability. While this study provides valuable insights on the distribution of PFAS in estuarine ecosystems, future studies should consider suspended particulate matter and tidal cycles to better understand the environmental fate of these contaminants.