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Konferens:Uppsala Health Summit: Chemical Pollution and One Health - From Reactivity to Proactivity, 24-25 October 2023

Per- and polyfluoroalkyl substances (PFAS) are a group of persistent organic contaminants of which some are toxic and bioaccumulative. Several PFAS can be formed from the atmospheric degradation of precursors such as fluorotelomer alcohols (FTOHs) as well as hydrochlorofluorocarbons (HFCs) and other ozone-depleting chlorofluorocarbon (CFC) replacement compounds. Svalbard ice cores have been shown to provide a valuable record of long-range atmospheric transport of contaminants to the Arctic. This study uses a 12.3 m ice core from the remote Lomonosovfonna ice cap on Svalbard to understand the atmospheric deposition of PFAS in the Arctic. A total of 45 PFAS were targeted, of which 26 were detected, using supercritical fluid chromatography (SFC) tandem mass spectrometry (MS/MS) and ultra-performance liquid chromatography (UPLC) MS/MS. C2 to C11 perfluoroalkyl carboxylic acids (PFCAs) were detected continuously in the ice core and their fluxes ranged from 2.5 to 8200 ng m−2 yr−1 (9.51–16,500 pg L−1). Trifluoroacetic acid (TFA) represented 71 % of the total mass of C2 – C11 PFCAs in the ice core and had increasing temporal trends in deposition. The distribution profile of PFCAs suggested that FTOHs were likely the atmospheric precursor to C8 – C11 PFCAs, whereas C2 – C6 PFCAs had alternative sources, such as HFCs and other CFC replacement compounds. Perfluorooctanesulfonic acid (PFOS) was also widely detected in 82 % of ice core subsections, and its isomer profile (81 % linear) indicated an electrochemical fluorination manufacturing source. Comparisons of PFAS concentrations with a marine aerosol proxy showed that marine aerosols were insignificant for the deposition of PFAS on Lomonosovfonna. Comparisons with a melt proxy showed that TFA and PFOS were mobile during meltwater percolation. This indicates that seasonal snowmelt and runoff from post-industrial accumulation on glaciers could be a significant seasonal source of PFAS to ecosystems in Arctic fjords.

Monitoring the vast number of micropollutants in the environment by using comprehensive chemical screening is a major analytical challenge. The aim of this study was to evaluate a comprehensive analysis method for screening purposes of fish muscle samples by comparing sample preparation methods for a broad range of mid-to non-polar contaminants. Five extraction and three clean-up methods were evaluated for the analysis of 60 compounds with a log Kow range between 0.8 and 8.3 in fish. Both fresh and freeze-dried muscle tissue and extraction sodium sulphate blanks were included to assess recoveries and matrix effects. The performance of the different methods was evaluated using both comprehensive target and nontarget analysis using high resolution mass spectrometry (HRMS). The results showed that open-column and ultrasonication extractions (recoveries mostly between 20 and 160 %) resulted in higher recoveries than accelerated solvent extraction (ASE) (recoveries mostly between 20 and 80 %) and bead mixer homogenization extractions (recoveries between 0 and 50 % for the whole Kow range). Multilayer silica was the clean-up method resulting in the lowest matrix effects and highest recoveries, however some compounds (mostly pesticides) were denatured under the acidic conditions used. The convenient and time efficient ultrasonication extraction followed by deactivated silica clean-up proved to be promising for both target and nontarget approaches. The large difference in recoveries and number of detected peaks using target and nontarget approaches between fresh and freeze-dried fish seen for all methods calls for careful consideration, and further studies are needed to improve performance for screening of mid-to non-polar compounds in freeze-dried fish.

Återanvändning av avloppsvatten för jordbruksbevattning är ett sätt att minska efterfrågan på sötvatten, men det kan också introducera läkemedel, personliga hygienprodukter och andra kemikalier i jordbrukets ekosystem och livsmedelskedja. Syftet med denna studie var att mäta förekomsten av en rad potentiellt skadliga organiska mikroföroreningar (OMP), såsom läkemedel, personliga hygienprodukter, industrikemikalier, bekämpningsmedel och per- och polyfluoralkylsubstanser (PFAS) i avloppsvatten som används för bevattning och i den mottagande jordbruksmarken. Bevattningsvatten bestående av renat avloppsvatten vid två anläggningar på Gotland provtogs vid fyra tillfällen under juli och augusti 2021. Dessutom togs prover på jord och daggmaskar i september 2021 efter skörd från två åkrar bevattnade med avloppsvattnet samt från en åker som inte hade bevattnats alls. Potatis som fortfarande var i marken togs från ett av de bevattnade fälten. Ett brett spektrum av OMP-koncentrationer (ng/l till ug/l) hittades i bevattningsvattnet, och totalt upptäcktes 35 av 77 analyserade OMP. Totalt 19 av 24 olika PFAS detekterades i bevattningsvattnet i intervallet 0,1-1000 ng/l. Extraherbart organiskt fluor (EOF) och totala oxiderbara prekursorer (TOP) mättes även i vattenproverna. Intervallet för EOF var 366-507 ng/l och endast två av totalt åtta bevattningsvattenprover visade en liten ökning av perfluoroktansyra (PFOA) och perfluorhexansyra (PFHxA) efter oxidation. Ingen av OMP:erna i denna studie upptäcktes i något av jordproverna. Perfluoroktansulfonsyra (PFOS) hittades över detektionsgränsen i jord från båda bevattnade fälten (0,14-0,17 ng/ d.w.) men låg under detektionsgränsen i jord från referensplatsen. Perfluorbutansyra (PFBA) hittades i låga nivåer men över detektionsgränsen i ett av de bevattnade fälten (0,22 ng/g d.w.) och den närliggande referensplatsen (0,27 ng/g d.w.). EOF-analysen av jord resulterade inte i någon ytterligare information då detektionsgränsen var relativt hög, The reuse of wastewater for agricultural irrigation is one way to reduce the demand for freshwater but it can also introduce pharmaceuticals, personal care products, and other chemicals into the agricultural ecosystem and food chain. The aim of this study was to measure a range of potentially harmful organic micropollutants (OMPs), such as pharmaceuticals, personal care products, industrial chemicals, pesticides, and per- and polyfluoroalkyl substances (PFAS), in wastewater effluent used for irrigation and in the receiving farmland. Four sampling occasions of effluent water at two wastewater treatment plants in Gotland were conducted during July and August 2021. In addition, soil and earthworms were sampled in September 2021 after harvest from two fields irrigated with the monitored wastewater and one field that had not been irrigated that season. Potatoes still in the ground were sampled from one of the irrigated fields. A wide range of OMP concentrations (ng/L to ug/L) were found in the effluent water, and in total 35 of 77 analyzed OMPs were detected. A total of 19 out of 24 different PFAS were detected in the effluent samples in the range of 0.1-1000 ng/L. Extractable organofluorine (EOF) and total oxidizable precursors (TOP) were measured in water samples in addition to target PFAS. The range for EOF in effluent samples were 366-507 ng/L and only two samples out of the total eight effluent samples showed a small increase in concentrations of perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA) after oxidation. None of the OMPs in this study was detected in any of the soil samples. Perfluorooctane sulfonic acid (PFOS) was found over the detection limit in soil from both irrigated fields (0.14-0.17 ng/g d.w.) but was below the detection limit at the reference site. Perfluorobutanoic acid (PFBA) was found at low levels closely above the detection limit in one of the irrigated fields (0.22 ng/g d.w.) and the nearby reference site (0.27 ng/g d.w.). The E

Per- and polyfluoroalkyl substances (PFAS) is a large group of anthropogenic compounds that is widely used, for example to manufacture grease- and water-repellent paper. Several PFAS have been found to pose a risk to the environment and humans due to their persistency, mobility, toxicity and bioaccumulative potential. Paper production in Sweden covers widely different products such as cardboard, liquid cardboard, writing paper, sack paper, hygiene paper (tissue), etc. In addition, there are also numerous closed paper industries. Current and historical use of PFAS in paper industries in Sweden and consequent emissions to the environment are not known. The purpose of this study was to assess if paper industries could be an important point source for PFAS in the environment by analysis of PFAS in sediment and water taken nearby paper industries. In total, 60 sediment samples from 13 sites in Sweden sampled during the time period 2015-2022, and eight surface water samples from three sites taken in 2021, were included in the study. A total of 68 non-polymer PFAS and extractable organofluorine (EOF) was targeted. The results from the screening study shows a wide range of the sum target PFAS-68, between below limit of detection (LOD) to 1181 ng/g dry weight (d.w.) in sediments close to paper industries in Sweden. The number and type of PFAS detected also varied. The PFAS-classes found in highest concentration in surface sediments were polyfluoroalkyl phosphate diesters (diPAP) (maximum 819 ng/g d.w.), fluorooctanesulfonamidoacetic acid (FOSAA) (maximum 137 ng/g d.w.), and N-ethyl perfluorooctane sulfonamido ethyl phosphate diester (diSAmPAP) (maximum 134 ng/g d.w.). DiSAmPAP was only semi-quantified due to poor separation of structural isomers and interferences from the sediment matrix. A general increase in concentrations with increasing sediment depth could be seen for the contaminated sites, and the maximum concentration in sediments of different depths reached 1084 ng, Per- och polyfluoralkylsubstanser (PFAS) är en stor grupp antropogena föreningar med bred användning, till exempel vid tillverkning av fett- och vattenavvisande papper. Flera PFAS har visat sig utgöra en risk för miljön och människor på grund av deras persistens, rörlighet, toxicitet och bioackumulerande egenskaper. Pappersproduktionen i Sverige omfattar olika typer av produkter såsom kartong, flytande kartong, skrivpapper, säckpapper, hygienpapper, etcetera. Nuvarande och historisk användning av PFAS i svensk pappersindustri kopplat till utsläpp till miljön är inte känd. Syftet med denna studie var att bedöma om pappersindustrier kan vara en viktig punktkälla för PFAS i miljön genom analys av PFAS i sediment och vatten i närheten av pappersindustrier. Totalt ingick 60 sedimentprover från 13 platser i Sverige provtagna under tidsperioden 2015–2022, och åtta ytvattenprover från tre platser tagna 2021. Analysen omfattade totalt 68 PFAS (icke-polymerer) och extraherbart organiskt fluor (EOF). Resultaten visar ett stort koncentrationsområde i sediment nära pappersindustrier i Sverige, från under detektionsgränsen (LOD) till 1181 ng/g torrvikt. Antalet och typen av detekterade PFAS varierade också. De PFAS-klasser som hittades i högst koncentration i ytsediment var polyfluoralkylfosfatdiestrar (diPAP, max 819 ng/g), fluoroktansulfonamidättiksyra (FOSAA, max 137 ng/g) och ämnet N-etylperfluoroktansulfonamidfosfatdiester (diSAmPAP, max 134 ng/g d). Koncentrationerna för diSAmPAP är semi-kvantifierade då matris och isomerer störde kvantifieringen. En generell ökning av koncentrationerna med ökande sedimentdjup kunde ses och den maximala koncentrationen i sediment från olika djup nådde 1084 ng/g för diPAP, 65 ng/g för FOSAA och 682 ng/g för diSAmPAP. De klasserna som vanligtvis mäts i undersökningar, PFCA och PFSA, nådde maximalt 6 och 7 ng/g i ytsediment, och 11 och 6 ng/g i sedimentkärnor. EOF följde samma trend som PFAS-koncentrationerna, med några få undantag, och varier

Thousands of per- and polyfluoroalkyl substances (PFAS) are on the global market, while only a minor proportion is monitored regularly in the environment. Wastewater treatment plants (WWTPs) have been suggested to be a point source for PFAS to the environment due to emission of effluent and sludge. In this study, 81 PFAS including two rarely studied perfluoroalkyl sulfonamide-based (FASA) copolymers were analyzed in sludge samples to understand the usage of PFAS in the society. Sludge samples (n = 28) were collected at four WWTPs in Sweden between 2004 and 2017. The total levels of 79 measured PFAS were between 50 and 1124 ng/g d.w. All sludge samples showed detectable levels of both C8- and C4-FASA-based copolymers. The concentrations of the FASA-based copolymers were proposed to be reported in fluorinated side-chain equivalents (FSC eq.), in order to compare the levels of the copolymers with the other neutral and anionic PFAS, as no authentic standards were available. The concentrations of the FASA-based copolymers in sludge were between 1.4 and 22 ng FSC eq./g d.w. A general predomination of precursor and intermediate compounds was observed. A lower contribution of perfluoroalkyl carboxylic acids was noted for the WWTPs more influenced by domestic emission when compared with more influenced by industrial emission. An overall declining trend in the total PFAS concentration was seen between the years 2004 and 2017. The present study observed a shift from the C8-based chemistry toward shorter chain lengths, included a declining trend for C8-FASA-based copolymer over the entire study period. These findings further demonstrate the occurrence of side-chain fluorinated copolymers in Sweden and that sludge is a useful matrix to reflect the usage of PFAS in society and the potential for environmental exposure.

Side-chain fluorinated polymers are speculated to be potential precursors to other non-polymeric aliphatic per- and polyfluoroalkyl acids (PFAAs). Limited knowledge of environmental occurrence of this compound class is partly due to lack of structural information and authentic standards. In this study, two novel fluorinated compounds, suspected to be side-chain fluorinated copolymers used in two commercial technical mixtures (Scotchgard™ Pre-2002 formulation and Scotchgard™ Post-2002 formulation) were analyzed and characterized in order to provide information to facilitate detection and quantification. The commercial mixtures were analyzed using tandem mass spectrometry and high-resolution mass spectrometry; besides already reported C4- and C8-fluoroalkylsulfonamido (FASA) side-chains, a proposed structure was determined for the perfluorooctane (C8) sulfonamide-urethane copolymer in the Pre-2002 formulation. Structural isomers were also observed for C4- and C8-FASA-based copolymers. Total fluorine analysis revealed that the Scotchgard™ Pre-2002 Formulation contained a fluorine content of 0.5% and 1.8% for the Scotchgard™ Post-2002 Formulation. The equivalent FASA side-chain content was determined to be 0.8% for Pre-2002 and 3.1% for Post-2002. Both C4- and C8-FASA-based copolymers underwent hydrolysis and oxidation and were transformed to their respective perfluoroalkyl side chain, which suggest that transformation products can be analyzed for example after total oxidizable precursor (TOP) assay. Both compounds were shown to strongly sorb to sediment particles, which also gives indications about their environmental fate and transport pathways.

Per- and polyfluoroalkyl substances (PFAS) have raised concerns due to their worldwide occurrence and adverse effects on both the environment and humans as well as posing challenges for monitoring. Further collection of information is required for a better understanding of their occurrence and the unknown fractions of the extractable organofluorine (EOF) not explained by commonly monitored target PFAS. In this study, eight pairs of raw and treated water were collected from drinking water treatment plants (DWTPs) around Taihu Lake in China and analyzed for EOF and 34 target PFAS. Mass balance analysis of organofluorine revealed that at least 68% of EOF could not be explained by target PFAS. Relatively higher total target concentrations were observed in 4 DWTPs (D1 to D4) when compared to other samples with the highest sum concentration up to 189 ng L-1. PFOA, PFOS and PFHxS were the abundant compounds. Suspect screening analysis identified 10 emerging PFAS (e.g., H-PFAAs, H-PFESAs and OBS) in addition to target PFAS in raw or treated water. The ratios PFBA/PFOA and PFBS/PFOS between previous and current studies showed significant replacements of short-chain to long-chain PFAS. The ratios of the measured PFAS concentrations to the guideline values showed that some of the treated drinking water exceeds guideline values, appealing for efforts on drinking water safety guarantee., Funding agencies:Major Science and Technology Program for Water Pollution Control and Treatment 2017ZX07201005National Key Research and Development Project of China 2021YFC3200801

Perfluoroalkyl acids (PFAAs) are highly persistent chemicals that are ubiquitously found in the environment. The atmospheric degradation of precursor compounds has been identified as a source of PFAAs and might be an important pathway for contamination. Lake Vättern is one of Sweden's largest lakes and is an important source for drinking water. In addition to contamination via atmospheric deposition, the lake is subject to several potential contamination sources via surface water inflow. The relevance of different sources is not well understood. A mass balance of selected PFAAs was assembled based on measured concentrations in atmospheric deposition, surface water from streams that constitute the main inflow and outflow, and surface water in the lake. The largest input was seen for trifluoroacetic acid (150 kg/year), perfluoropropanoic acid (1.6 kg/year), perfluorobutanoic acid (4.0 kg/year), and perfluoro-octanoic acid (1.5 kg/year). Both atmospheric deposition and surface water inflow was found to be important input pathways. There was a positive correlation between the input of most perfluoroalkyl carboxylic acids via atmospheric deposition and global radiation and between the input via surface water inflow and catchment area. These findings highlight the importance of atmospheric oxidation of volatile precursor compounds for contamination in surface waters.

The ubiquitous occurrence of a few per- and polyfluoroalkyl substances (PFAS) in humans and the environment has been previously reported. However, the number of PFAS humans and the environment are potentially exposed to is much higher, making it difficult to investigate every sample in detail. More importantly, recent studies have shown an increasing fraction of potentially unknown PFAS in human samples. A screening tool for identifying samples of concern that may contain high PFAS levels, to be studied more thoroughly, is needed. This study presents a simplified workflow to detect elevated PFAS levels using extractable organofluorine (EOF) analysis. A fluorine mass balance analysis on samples with high EOF, targeting 63 PFAS, can then confirm the PFAS contamination. Whole blood samples from a cohort of individuals with historical drinking water contamination from firefighting foams (n = 20) in Ronneby (Sweden) and a control group (n = 9) with background exposure were used as a case study. The average EOF concentration in the Ronneby group was 234 ng/mLF (<107-592 ng/mLF) vs 24.8 ng/mLF (17.6-37.8 ng/mL F) in the control group. The large difference (statistically significant, p < 0.05) in the EOF levels between the exposed and control groups would have made it possible to identify samples with high PFAS exposure only using EOF data. This was confirmed by target analysis, which found an average ∑PFAS concentration of 346 ng/mL in the exposed group and 7.9 ng/mL in the control group. The limit of quantification for EOF analysis (up to 107 ng/mLF using 0.5 mL whole blood) did not allow for the detection of PFAS levels in low or sub parts per billion (ng/mL) concentrations, but the results indicate that EOF analysis is a suitable screening method sensitive enough to detect elevated/significant/exposure above background levels by known or unknown PFAS., Funding agency:Enforce Research Profile 20160019

Microplastics are ubiquitous in aquatic ecosystems, but little information is currently available on the dangers and risks to living organisms. In order to assess the ecotoxicity of environmental microplastics (MPs), samples were collected from the beaches of two islands in the Guadeloupe archipelago, Petit-Bourg (PB) located on the main island of Guadeloupe and Marie-Galante (MG) on the second island of the archipelago. These samples have a similar polymer composition with mainly polyethylene (PE) and polypropylene (PP). However, these two samples are very dissimilar with regard to their contamination profile and their toxicity. MPs from MG contain more lead, cadmium and organochlorine compounds while those from PB have higher levels of copper, zinc and hydrocarbons. The leachates of these two samples of MPs induced sublethal effects on the growth of sea urchins and on the pulsation frequency of jellyfish ephyrae but not on the development of zebrafish embryos. The toxic effects are much more marked for samples from the PB site than those from the MG site. This work demonstrates that MPs can contain high levels of potentially bioavailable toxic substances that may represent a significant ecotoxicological risk, particularly for the early life stages of aquatic animals.

The high proportion of unidentified extractable organofluorine (EOF) observed globally in humans and the environment indicates widespread occurrence of unknown per- and polyfluoroalkyl substances (PFAS). However, efforts to standardize or assess the reproducibility of EOF methods are currently lacking. Here we present the first EOF interlaboratory comparison in water and sludge. Three participants (four organizations) analyzed unfortified and PFAS-fortified ultrapure water, two unfortified groundwater samples, unfortified wastewater treatment plant effluent and sludge, and an unfortified groundwater extract. Participants adopted common sample handling strategies and target lists for EOF mass balance but used in-house combustion ion-chromatography (CIC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. EOF accuracy ranged from 85-101% and 76-109% for the 60 and 334 ng L-1 fluorine (F) - fortified water samples, respectively, with between-laboratory variation of 9-19%, and within-laboratory variation of 3-27%. In unfortified sludge and aqueous samples, between-laboratory variation ranged from 21-37%. The contribution from sum concentrations of 16 individual PFAS ( n-ary sumation PFAS-16) to EOF ranged from 2.2-60% but extended analysis showed that other targets were prevalent, in particular ultra-short-chain perfluoroalkyl acids (e.g. trifluoroacetic acid) in aqueous samples and perfluoroalkyl acid-precursors (e.g. polyfluoroalkyl phosphate diesters) in sludge. The EOF-CIC method demonstrated promising accuracy, robustness and reporting limits but poor extraction efficiency was observed for some targets (e.g. trifluoroacetic acid).

Emergent aquatic insects are important food subsidies to riparian food webs but can also transfer waterborne contaminants to the terrestrial environment. This study aimed to quantitatively assess this biodriven transfer for per- and polyfluoroalkyl substances (PFAS). Aquatic insect larvae, emergent aquatic insects, terrestrial consumers, sediment, and water were collected from a contaminated lake and stream and an uncontaminated pond, and analyzed for PFAS and stable isotopes of carbon and nitrogen. Top predators in this study were spiders, which showed the highest average ∑24PFAS concentration of 1400 ± 80 ng g–1 dry weight (dw) at the lake and 630 ng g–1 dw at the stream. The transfer of PFAS from the lake to the riparian zone, via deposition of emergent aquatic insects, was 280 ng ∑24PFAS m–2 d–1 in 2017 and only 23 ng ∑24PFAS m–2 d–1 in 2018. Because of higher production of emergent aquatic insects, the lake had higher PFAS transfer and higher concentrations in terrestrial consumers compared to the stream, despite the stream having higher PFAS concentration in water and aquatic insect larvae. Our results indicate that biodriven transfer of PFAS from the aquatic systems and subsequent uptake in terrestrial food webs depend more on emergence amounts, i.e., aquatic prey availability, rather than on PFAS concentrations in water and aquatic prey.