Till Örebro universitet

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 approach, 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.

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.

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.

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.

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.

This study presents a comprehensive chemical and toxicological screening of chemicals extracted from WEEE (waste from electrical and electronic equipment) plastics. Chemical identification was conducted through suspect and target screening methods, revealing a diverse array of hazardous compounds including polycyclic aromatic compounds (PACs), organophosphate flame retardants (OPFRs), phthalates, benzotriazoles, and others. Toxicological endpoints included cell morphological phenotypes, inflammatory response, aryl hydrocarbon receptor (AhR) activation, activation of estrogenic receptor, and anti-androgenic activity. Results demonstrated that WEEE plastic chemicals significantly altered cell morphological phenotypes, particularly affecting the cytoskeleton, endoplasmic reticulum (ER), and mitochondrial measures. Moreover, WEEE chemicals induced inflammatory responses in resting human macrophages and altered ongoing inflammatory responses in lipopolysaccharide (LPS)-primed macrophages. Furthermore, WEEE chemicals exhibited potent AhR agonistic activity, activated estrogen receptor-α (ERα), and inhibited androgen receptor (AR) activation. The findings suggest that WEEE plastic chemicals exert their effects through multiple modes of action, targeting various subcellular sites. Thus, a combined approach utilizing non-target and target screening tools is essential for comprehensively assessing the toxic effects and health hazards associated with WEEE plastic chemicals.

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.

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.