Per- and polyfluoroalkyl substances (PFAS) are a group of highly fluorinated compounds which comprises of more than 4700 substances. A smaller number of those substances is rou-tinely measured, usually the short (C4-C7) and long chain PFAS (>C7). Detection of PFAS in different water matrices including wet precipitation have been done previously in a limited number of studies, including ultra-short chain compounds (C1-C3). Ultra-short chain com-pounds have however not been investigated to a larger extent. In this study, twelve rainwater samples from Råö have been analysed, each representing a composite sample of one month. Long (C8-C18), short as well as ultra-short chain PFAS have been included in the analysis. Long and short chain compounds were analysed with ultra-performance liquid chromatography tan-dem mass spectrometer (UPLC-MS/MS) and ultra-short chain compounds with ultra-perfor-mance convergence chromatography tandem spectrometer (UPCC-MS/MS). Long and short-chain PFAS had a total detectable concentration of 5.1-110 ng/L. A seasonal trend was also studied, which showed a significant difference when performing a Kruskal Wallis test in meas-ured total mean long and short chain PFAS concentration. Dunnet´s test indicated a significant difference between all the seasons. Highest concentrations were measured during summer and lowest during winter. Ultra-short chain compounds analysed by UPCC MS/MS had a total concentration between 16-410 ng/L. No significant difference in total ultra-short PFAS mean concentration could be seen between different seasons using a Kruskal Wallis test. The total PFAS concentration in the rain samples ranged from 28 to 540 ng/L, where ultra-short chain PFAS contributed to 58-92 % of the total concentration. Which makes them an important group to include in future measurements of PFAS in water samples and especially in rainwater sam-ples.

Per- och polyfluorerade alkylsubstanser (PFAS) är en stor grupp industriellt framställda ämnen som fått stor spridning i miljön. På grund av PFAS persistens blir ämnena kvar länge i vår miljö och spridning kan fortgå ifrån förorenade områden under lång tid. Högst halter i miljön i Sverige har noterats i anslutning till brandövningsplatser där man använt brandskum innehållande PFAS-ämnen.De vanligaste källorna till människors exponering för PFAS är via kosten, inklusive dricksvatten. PFAS binder till proteiner i kroppen och ansamlas i blodet och levern samt lungor och njurar. Exponering för förhöjda halter under lång tid har visats ge påverkan på blodfetter, en reducerad födelsevikt samt påverkan på leverceller. Den effekt som noterats vid lägst exponeringsdos är påverkan på immunförsvaret.I januari 2020 skickade Livsmedelsverket ut en enkät till Sveriges kommunala kontrollmyndigheter i syfte att kartlägga halter av PFAS i kommunalt dricksvatten. 261 kommuner av 290 (90 %) besvarade enkäten med uppgifter om 1462 vattenverk. Ett urval gjordes till stora vattenverk, som försörjer fler än 500 personer, vilka omfattade 580 stycken. Totalt 86 kommuner hade analyserat PFAS i dricksvatten från minst ett vattenverk. Detekterbara halter påträffades i dricksvattnet från 74 av samtliga 154 vattenverk där analyser genomförts. I dricksvattnet från 15 vattenverk, vilka tillsammans försörjer cirka 2,2 miljoner människor låg summahalterna av PFAS över 10 ng/l. Den högsta summahalten som uppmättes var 40 ng/l i dricksvattnet från ett vattenverk. Resultaten från denna kartläggning visar på lägre halter i kommunalt dricksvatten jämfört med undersökningar från tidigare år vilket indikerar att åtgärder vidtagits i syfte att sänka PFAS-halterna i dricksvattnet i Sverige. / Per- and polyfluorinated alkyl substances (PFAS) is a large group industrially synthesized compounds being wide spread in the environment. Due to the persistence, the compounds stays in the environment and can further disperse from polluted areas during a long time. The highest levels in the environment in Sweden have been found adjacent to firefighting training facilities using firefighting foam containing PFAS.Humans are exposed to PFAS mainly through food, including drinking water. PFAS binds to proteins in the blood and liver as well as in the lungs and kidney. Exposure during a prolonged time have shown to affect blood lipids, reduce birth weight and affect liver cells. The critical effect observed at the lowest dose is adverse effects on the immune system.In January 2020 the Swedish Food Agency sent out a questionnaire to the municipal control authorities aiming to map levels of PFAS in municipal drinking water. 261 municipalities of 290 (90 %) answered the questionnaire with information including 1462 water works. A selection was made including the larger water works supplying at least 500 persons, resulting in 580 water works. In total, 86 municipalities had analysed PFAS in drinking water from at least one water work. Detectable levels were found in 74 out of 154 water works, where analyses had been performed. In drinking water from 15 water works, supplying approximately 2.2 million people, the sum levels of PFAS exceeded 10 ng/l. The highest sum levels of PFAS in drinking water were 40 ng/l, found in one water work. The results from this survey shows lower levels in municipal drinking water compared to earlier studies, indicating that measures haven been taken aiming to lower the levels of PFAS in drinking water in Sweden.

<p>Perfluoroalkyl substances are synthetic organic chemicals of environmental concern because they have been associated with adverse effects in both human epidemiological studies and standard laboratory animals. In the environment, PFAS occur as mixtures, especially in areas with a history of PFAS application, such as aqueous film forming foam (AFFF) sites. Among the PFAS, perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic acid (PFHxS) are the most common, and occur at the highest concentrations. Thus, amphibian populations at or near AFFF sites are at risk of exposure to known bioaccumulative and persistent chemicals, likely compromising the physiology and body condition of the animals. Here, we exposed northern leopard frogs to environmentally relevant concentrations of 0.5 and 1 ppb PFOS and PFHxS, alone or as a mixture comprised of 0.5 ppb PFOS and 0.5 ppb PFHxS. Univariate analyses showed that in the larval stages, tadpoles exposed to PFAS had significantly reduced scaled mass indexes (SMI’s) relative to the control, and only the organisms exposed to PFHxS 0.5 ppb were significantly larger. Sex did not significantly influence toxicity in the later stages (GS 42 & 46), indicating no sex-related effects. Altered body condition (i.e., fat stores) in the larval stages indicate potential effects to energy balance. There is a need to assess fitness-related effects as amphibians’ transition into the terrestrial environment, and include endpoints such as: reproductive, developmental, immunological, mating, feeding, competition, and survival. Early developmental effects in the larval stages also suggests that earlier developmental endpoints may be of interest. Establishing ecological risk assessments for PFAS are necessary, as they are toxic, persistent, and bioaccumulative.</p>

GenX, a newly synthesized per- and polyfluoroalkyl substance (PFAS), has gained attention as a supposedly safer replacement for the long-chain PFAS, PFOA. Given the thyroid gland being known to be a target organ for the health effects of PFOA, it is crucial to investigate GenX potential impact on the thyroid gland. Thyroid hormones play a critical role in normal development and metabolism, emphasizing the importance of assessing the thyroid-disrupting effects of GenX for future regulatory considerations.A review of the existing scientific literature revealed potential genotoxicity and cytotoxicity in thyroid cells, reduced postnatal survival rates, and altered levels of thyroid hormones following GenX exposure. Further research is needed to establish definitive conclusions regarding the thyroid-impairing effects of GenX. This study highlights the necessity for additional investigations to improve our understanding of the potential risks and effects associated with GenX exposure on thyroid function. / GenX, en nyligen framtagen PFAS, har uppmärksammats som en påstått säkrareersättning för PFOA, en av de långkedjiga PFAS. Sköldkörteln är känd som ettmålorgan för skadliga hälsoeffekter av PFOA vilket gör det intressant att undersöka GenX eventuella påverkan på sköldkörteln. Sköldkörtelhormoner är viktiga för normal utveckling och ämnesomsättning, vilket betonar vikten av att bedöma GenX potentiella störande effekter på sköldkörtelfunktionen för framtida regleringsåtgärder. En genomgång av befintlig vetenskaplig litteratur visade potentiell genotoxicitet och cytotoxicitet i sköldkörtelceller, minskad överlevnad efter födseln samt förändrade nivåer av sköldkörtelhormoner efter GenX-exponering. Vidare forskning behövs för att fastställa definitiva slutsatser angående GenX:s sköldkörtelpåverkande effekter. Denna studie belyser nödvändigheten av ytterligare undersökningar för att förbättra vår förståelse för de potentiella riskerna och effekterna som är förknippade medsköldkörtelfunktion och GenX-exponering.

Per- and polyfluorinated substances (PFASs) have become an urgent topic in the water treatment industry in recent years as a consequence of new scientific discoveries of the correlation between the ingestion of some PFASs and their toxicity in humans and other organisms. PFASs are synthetic compounds present in a variety of products. Due to their desirable physical and chemical properties, PFASs are found in everything from clothes and furniture to aqueous fire-fighting foams. These compounds have also been identified in food and drinking water. The flourine-carbon bond present in these chemicals are exceptionally strong. Hence PFASs are persistent in nature when leaked to the environment. Additionally, the mobility properties of PFASs in the soil leads to contamination of surface and groundwater, necessitating actions from drinking water treatment plants (DWTP).  Nanofiltration plants have shown to successfully reduce the PFASs content in contaminated waters. The accumulation of PFASs in the concentrate is a potent source of these compounds and requires treatment before leaving the DWTP. Foam fractionation (FF) is an aeration technique that utilizes the hydrophobic properties of the PFASs compounds, in which PFASs adsorbs to the interfaces of introduced rising air-bubbles. The foam forming at the surface is then extracted, reducing the contamination.  In this study, the efficacy of the FF system on a concentrate from a two-stage nanofiltration membrane was evaluated. Also, the ability of surfactants to enhance the PFAS reduction was explored. The study was conducted in two parts. The first part was executed in a laboratory scale environment where five surfactants were added to a batchwise FF system. A minimum dose was determined and four experimental runs were then executed for each surfactant: Zero surfactant, 1x minimum dose, 2x minimum dose and 5x minimum dose. The results were evaluated and the surfactant showing the greatest improvement of PFASs removal, in this study a cationic surfactant, was chosen for further investigations in the second part. A continuous pilot FF system was used in the second part, the inner diameter of the colon was 54 mm, the height of the water column was held at 1 m prior to the aeration, the contact time (CT) was 10 minutes and the air-flow rate was set to be 4 L/min in all runs. Four experimental runs were conducted with different doses of the cationic surfactant: Zero surfactant, 1x minimum dose, 2x minimum dose and 3x minimum dose. Each experiment was repeated three times. A total of 12 runs were performed.  The results showed a removal efficiency of &gt; 99 % of long-chained PFASs in all conducted experimental runs. Without the addition of surfactant, the average removal efficiency of ∑ short-chained PFASs was 61 % whereas maximum removal (77 %) was obtained with the highest surfactant dose applied. The mean reduction of ∑PFASs was 90 % in the zero surfactant run and 94 % in the highest dose experiment. The main findings from the study were that: 1) FF is an efficient method for the removal of long-chained PFASs from concentrate 2) Surfactants can be added to increase the removal of short-chained PFASs, 3) Higher dosing of the surfactant positively correlated with the removal efficiency of ∑short-chained PFASs in the FF system, however the relationship was not linear. / Per- and polyfluorerade ämnen (PFAS) är ett högaktuellt forskningsområde inom dricksvattenproduktion. På senare år har ny forskning påvisat korrelationen mellan intag av vissa PFAS-ämnen och hälsoproblem hos både människor och djur. PFAS är syntetiskt framställda kemikalier som förekommer i flertalet av våra vardagliga produkter på grund av dess fördelaktiga fysiska- och kemiska egenskaper. PFAS används i allt från smink och möbler till brandskum men har också påträffats i dricksvatten och mat. Kol-fluor bindningen som förekommer i alla PFAS-ämnen tillhör den organiska kemins starkaste bindningar. Följaktligen bryts PFAS-ämnen ned extremt långsamt när de hamnar i naturen. PFAS förmåga att mobilisera sig i jorden leder till kontaminering av yt- och grundvatten vilket tvingar dricksvattenverk att vidta åtgärder.  Nanofiltration har visat sig vara en kraftfull metod för att rena vatten från PFAS. I koncentratet, det vill säga det vatten som inte renas genom membranen, ackumuleras PFAS vilket förutsätter en separat reningsprocess innan vattnet kan släppas ut i naturen. Skumfraktionering är en luftbaserad teknik som utnyttjar hydrofobiciteten i PFAS. PFAS-ämnen adsorberas till ytan hos de injicerade luftbubblorna och transporteras till vattenytan där det bildar ett skum. Uppsamling av skummet reduceras således kontamineringen.  I den här studien bedömdes effektiviteten av skumfraktionering på koncentratet från ett två- stegs nanofiltrationsmembran. Därutöver undersöktes effekterna av att tillföra surfaktanter till systemet för att optimera reduceringen. Studien genomfördes i två delar. Den första delen ufördes i en mindre skala där 5 olika surfaktanter adderades till en satsvis- skumfraktioneringsprocess. Initialt bestämdes en minimum dosering för alla surfaktanter. Totalt genomfördes 4 experiment: Ingen surfaktant, 1x minimum dosen, 2x minimum dosen, 5x minimum dosen. Den surfaktant som påvisade bäst effekt på reduceringen av PFAS, i detta fall en katjonisk surfaktant, användes sedan.  I den andra delen av arbetet användes en kontinuerlig skumfraktioneringsprocess. Den inre diametern på kolonnen var 54 mm, vattenkolumnen hölls konstant på 1 m innan luftningen, kontakttiden var 10 min och lufthastigheten var satt till 4 L/min. Totalt genomfördes 4 experiment: Ingen surfaktant, 1x minimum dosen, 2x minimum dosen, 3x minimum dosen. Varje experiment upprepades tre gånger.  Resultatet visade att &gt; 99 % av ∑långkedjiga PFAS-ämnen reducerades i alla genomförda experiment. Den genomsnittliga reduktionen av ∑kortkedjiga PFAS-ämnen var 63 % i experimenten utan surfaktant, medan i experimenten med den högsta doseringen var reduktionen 77 %. Den genomsnittliga reduktionen av ∑11 PFAS var 94 % för den högsta doseringen medans den var 90 % i experimentet utan surfaktant. Studien visade att:  1) Skumfraktionering är en effektiv metod för att rena koncentrat från långkedjiga-PFAS 2) Surfaktanter kan fördelaktigen användas för att optimera reningen av kortkedjiga-PFAS ämnen. 3) Högre dosering av surfaktanter korrelerade med högre reduktion av ∑kortkedjiga PFAS i skumfraktioneringsprocessen, ökningen var dock inte linjär.

Tidigare studier har visat på höga halter av per- och polyfluorerade alkylsubstanser (PFAS) ilakvatten från avfallsanläggningar. Avfallsanläggningar i Sverige har idag inga krav på attrena bort PFAS från lakvatten, och anläggningarna har generellt inte ett reningssystem som äranpassat för att rena den typen av ämnen. EU stramar hela tiden åt kraven kring utsläpp ochanvändning av PFAS och det kan därför vara bra för en avfallsanläggning att ha översikt påhur mycket PFAS det släpps ut från deponi- och avfallsverksamheten och vilka eventuellaåtgärder som skulle kunna vidtas för detta problem. I denna uppsats används analysresultat av22 PFAS ämnen från nio provtagningspunkter på Gärstad avfallsanläggning, för attundersöka avfallsanläggningens utsläpp av PFAS. Resultaten för studien visar att deuppmätta värdena för summa PFAS 22 för provpunkterna ligger mellan 410 ng/l – 58 000ng/l. PFAS ämnen med kortare kedja (4 – 8 kol) har uppmätts i högre halter än de med längrekedja (9 – 13 kol). Resultaten visade även högre halter av perfluorerade karboxylater (PFCA)än perfluorerade sulfonsyror (PFSA). / Previous studies have shown high levels of per- and polyfluorinated alkyl substances (PFAS)in leachate from waste facilities. Waste facilities in Sweden currently have no requirements topurify PFAS from leachate, and the facilities generally do not have a treatment system that isadapted to purify this type of substances. The EU is constantly tightening the requirementsregarding the release and use of PFAS, and it can therefore be good for a waste facility tokeep track of how much PFAS is released from landfill and waste operations and whatpossible measurements could be taken for this problem. In this essay, analysis results of 22PFAS substances from nine sampling points at Gärstad waste facility have been used, toinvestigate the waste facility's discharge of PFAS. The results of studies show that themeasured values for total PFAS 22 at the sampling spots are between 410 ng/l - 58,000 ng/l.PFAS substances with a shorter chain (4 – 8 carbons) have been measured at higherconcentrations than those with a longer chain (9 – 13 carbons). The results also showedhigher levels of perfluorinated carboxylic acids (PFCAs) than perfluorinated sulfonic acids(PFSAs).

Since the discovery of per- and polyfluoroalkyl substances (PFAS) in the mid-20th century, their usage has increased significantly. Thanks to their unique properties, they have proven to be useful in many industries. Over the past decades, there has been a growing awareness of the adverse effects associated with the compounds. Exposure to PFAS has been linked to several health implications, prompting efforts to identify sources of exposure to these substances. Given that the construction industry heavily relies on materials with high durability and functionality, it is one of the sectors that uses PFAS extensively. The average human spends approximately 90% of their time indoors, underscoring the relevance of investigating how building materials contribute to PFAS exposure. This study aims to examine the extent of PFAS in building materials on the Swedish market. To relate PFAS exposure from building materials to potential environmental and health impacts, a compilation of available research was conducted. To investigate the occurrence of PFAS in building materials, a systematic search of 4,730 PFAS was conducted on SundaHus assessment system. A total of 15 different PFAS were found in products 628 times. The most prevalent product categories included valves, lighting fixtures, and paints. While these findings offer insights into the prevalence of PFAS in building materials on the Swedish market, further research could enhance the understanding through broader searches in terms of including more databases and substances. To understand the risks associated with PFAS in building materials, greater knowledge about PFAS emissions is needed. / Sedan upptäckten av per- och polyfluorerade alkylsubstanser (PFAS) under mitten av 1900-talet har deras användning ständigt ökat. Detta beror på deras unika egenskaper som har visat sig vara användbara inom många branscher. Under de senaste årtiondena har medvetenheten om de negativa effekterna av ämnena också ökat och exponering har kopplats till flera olika hälsoeffekter. Forskning har därför utförts för att kartlägga källorna till exponering. Byggindustrin är beroende av material med hög hållbarhet och funktionalitet och är därför en av de branscher som har använt PFAS i stor utsträckning. Eftersom vi människor spenderar i genomsnitt 90% av vår tid inomhus är det viktigt att undersöka hur byggmaterial påverkar människors exponering för PFAS. Syftet med denna studie är att undersöka förekomsten av PFAS i byggmaterial på den svenska marknaden. För att koppla förekomsten av PFAS i byggmaterial till möjliga miljö- och hälsoeffekter har tillgänglig forskning sammanställts. Förekomsten av PFAS i byggmaterial undersöktes genom en systematisk sökning av 4730 PFAS i SundaHus materialbedömningssystem. Denna sökning identifierade 15 olika PFAS, vilka förekom totalt 628 gånger i de registrerade produkterna. De främsta produktkategorierna var ventiler, belysningsarmaturer och färg. Resultatet påvisar förekomsten av PFAS i byggmaterial på svenska markanden men belyser även behovet av ytterligare forskning. För att fördjupa förståelsen skulle studien kunna utvecklas med en bredare sökning som inkluderar fler produktregister och ämnen. Mer forskning krävs för att fullständigt bedöma hälsoriskerna relaterade till PFAS i byggmaterial, särskilt gällande deras förmåga att emittera.

Perfluorooctane sulfonate (PFOS) and related perfluoroalkyl surfactants (PFAS) are ubiquitous contaminants of increasing public concern due to their environmental persistence, toxicity, and bioaccumulation. These perfluorinated compounds have been used for more than half a century in a wide variety of industrial and consumer products ranging from stain repellents such as Teflon® to aqueous fire-fighting foams and to grease-proof food packing. The public health and environmental risks posed by PFAS have driven environmental agencies and the industry to restrict their use to specific applications where they cannot be replaced by other chemicals. The sources and pathways of PFOS and its derivatives in the environment are not well understood. Analysis of environmental samples is critical to understand the fate, transport and persistence of these emerging contaminants. Techniques based on fluorine nuclear magnetic resonance (¹⁹F NMR) spectroscopy and high performance liquid chromatography (HPLC) with suppressed conductivity detection were successfully developed to monitor the presence of PFAS in water samples. Chromatographic separation of C₄ to C₈ PFAS surfactants was achieved using a C₁₈ reversed-phase column and a mobile phase consisting of a mixture of boric acid and acetonitrile at mixing ratios ranging from 75:25 to 45:55 (v/v). The combination of these two techniques was very effective for characterization and routine quantification of PFOS and related chemicals. Analytical methods based on ¹⁹F NMR, HPLC-suppressed conductivity detection, and liquid chromatography with tandem mass spectrometry (LC-MS/MS) were employed to characterize commercial PFOS samples. Linear and branched PFOS isomers in a percentage ratio of 75:25 were identified. Municipal wastewater treatment systems are one of the major sources of PFAS emissions into the environment. The presence of PFAS in sewage sludge from two wastewater treatment plants in Tucson, Arizona, was investigated. Sludge samples were washed with acetic acid and extracted with a mixture of acetic acid and methanol. The extract was cleaned and concentrated by means of solid phase extraction. LC-MS/MS operating in the selective ion monitoring (SIM) mode was employed to assess the presence of perfluorosulfonates, perfluorosulfonamides, and perfluorocarboxylates in sewage sludge samples. PFOS was the only perfluoroalkyl chemical detected in municipal sludge samples at a concentration of 77 ± 5 g kg⁻¹ sludge dry weight. Cost-effective treatment techniques for removing PFAS from industrial effluents are needed to minimize discharges of these pollutants. Reductive dehalogenation is widely applied to the degradation of highly chlorinated compounds. Hence, the susceptibility of PFOS and related compounds to biological and chemical reductive dehalogenation was evaluated in batch assays. PFAS were not reductively dehalogenated by different microbial consortia even after periods of incubation exceeding 2 y, confirming the high resistance of these compounds to microbial degradation. The anaerobic biodegradability of PFOS and perfluorobutane sulfonate (PFBS) samples exposed to electrochemical pretreatment with boron-doped diamond film electrodes was also investigated. The oxidation decreased the concentration of PFAS and dissolved organic carbon in solution, confirming the destruction of these compounds. However, the oxidative treatment did not enhance the susceptibility of PFAS to microbial degradation even after extended periods of incubation (> 1 y). In contrast, PFOS was reductively dehalogenated with a biomimetic system based on vitamin B12 as the catalyst and Ti(III) citrate as the reducing agent. The optimal treatments conditions of the reaction were 260 μM vitamin B₁₂, 36 mM Ti(III) citrate, 70°C and solution pH 9.0. Interestingly, branched PFOS isomers were more prone to degradation by vitamin B₁₂ catalysis compared to the linear isomer. Removal of 3 mol Fper mol of technical PFOS and 12 mol F- per mol of branched PFOS isomers was achieved. Defluorination of PFOS was also observed at environmental relevant conditions of 30°C and pH 7.0, albeit at lower degradation rates. Fluoride and carbon dioxide were identified as the major products of the chemical defluorination. Traces of partially fluorinated volatile compounds were also detected in the headspace. The feasibility of removing PFAS compounds from aqueous streams by sorption onto granular activated carbon (GAC), zeolite, and wastewater treatment sludge was examined in batch isotherm experiments. The fluorocarbon chain and the functional group influenced sorption of the anionic surfactants, PFOS adsorbed more strongly to GAC than perfluorooctanoic acid (PFOA) and PFBS. Activated carbon showed the highest affinity for PFOS (Freundlich K(F) values of 36.7 to 60.9) followed by the hydrophobic, high-silica zeolite NaY (Si/Al 80, K(F) of 31.8) and lastly anaerobic sludge (K(F) of 0.95 to 1.85). GAC sorption is a suitable treatment for the removal of anionic perfluoroalkyl surfactants when present at low concentrations. Fluoride has been identified as the major product of the reductive dehalogenation of PFOS and derivatives. Thus, the toxicity of inorganic fluoride towards the main microbial populations responsible for the removal of organic constituents and nutrients in wastewater treatment processes was also studied. Fluoride concentrations ranging from 18 to 43 mg L⁻¹ caused 50% inhibition (IC₅₀) of the activity of propionate- and butyratedegrading microorganisms and of acetate-utilization by methanogens evaluated under mesophilic and thermophilic conditions. All other microbial populations evaluated in this study, i.e., glucose fermenters, aerobic glucose-degrading heterotrophs, denitrifying bacteria, and H₂-utilizing methanogens tolerated fluoride at very high concentrations (> 500 mg L⁻¹). In the same manner, H₂-utilizing methanogens also tolerated PFOS and PFBS at concentrations as high as 200 and 500 mg L⁻¹, respectively.

Per- and polyfluoroalkylated substances (PFASs) are a large group of organic chemicals that have gained an increased attention during recent years. Many of the compounds have shown to be persistent, toxic and bioaccumulating and they are found in water, soils, sediments, biota, animals and humans across the globe. The effects of PFASs to humans and animals are still being debated. It is suspected that the compounds can be carcinogenic, disrupt different hormone systems and have other severe effects. The main transport pathways of PFASs to soil are applied PFAS based firefighting foam, soil improvers and waste from industries producing PFASs or PFAS based products. Once the PFASs find their way to the soil the risk for leaching to drinking water supplies and aquatic ecosystems becomes some of the issues of great concern. In order to be able to evaluate the potential leakage of PFASs from different contaminated soils it is important to know how the PFASs interact with the soil matrix and what parameters that affects these interactions. The objective of this study was to investigate the influence of organic carbon (OC), Ca2+ ions and active carbon (AC) on the n of PFCAs and PFSAs to soil. The PFCAs examined were PFHxA, PFOA, PFNA, PFDA, PFUnDA, PFOcDA, PFHxDA and PFOcDA and the PFSAs examined were PFBS, PFHxS, PFOS and PFDS. Batch experiments were performed on soils with varying concentrations of TOC, Ca2+ and AC. The samples were spiked with PFAS native standard solution containing the 12 target PFASs. All studied parameters showed a positive influence on the sorption of PFASs to soil. The AC was found to have the highest influence on the sorption. The OC was however found to be the most important soil parameter influencing the sorption of PFASs to soil. In order to investigate the influence of aging on the sorption of PFASs, batch experiments were also conducted on soils from four different PFAS contaminated sites. The results showed that the aging positively influenced the strength of the interactions between PFASs and soil. The organic carbon normalized distribution coefficients (Koc) showed a positive correlation with the carbon chain length of the PFAS molecules and also with the substitution of a carboxylic group with a sulfonic group. The log Koc values calculated in this study decreased in the following order PFDS (log Koc3.8 0.3) &gt; PFOS &gt; (log Koc2.8 0.3) &gt; PFUnDA (log Koc 3.2 0.2) &gt; PFDA (log Koc2.7 0.1) &gt; PFNA (log Koc2.0 0.1) &gt; PFHxS (log Koc1.9 0.1) &gt; PFOA (log Koc1.8 0.3) &gt; PFHxA (log Koc1.6 0.3) &gt; PFBS (log Koc 1.5 0.2). The log Koc values found in this study were within the range of previously reported log Kocvalues.

PFAS är en grupp poly- och perfluorerade ämnen som framställs industriellt och förekommer i ett flertal produkter såsom impregnerade papper och textilier, brandskum och rengöringsmedel, detta på grund av dess smuts, vatten- och fettavstötande egenskaper. Ämnena klassas som PBT ämnen, persistenta, bioackumulerande och toxiska, vilket gör dem till ett hälsoproblem för människor och djur. Denna studie undersökte förekomsten av PFCA, PFSA och PAPS i micropopcorn, samt om migration från förpackning till majskorn innan tillagning förekom och om PFAS i popcornen kunde utgöra en hälsorisk för människor. Proverna bereddes genom att tillaga ett prov i mikrovågsugn, ett i kastrull innehållande majskärnor samt fettet från micropopcornpåsen och ett där majskärnorna tvättades rena från fett från påsen och därefter tillagades med rapsolja i kastrull. Proven extraherades bland annat med en SPE Wax + HLB, separerades i en Acuity UPLC och identifierades med hjälp av en Xevo TQ-S-quadrupole masspektrometer med atmosfäriskt elektrospraygränssnitt i negativt läge samt analyserades i mjukvaran Masslynx. Resultaten för PFSA/PFCA visade högst frekvens av ämnen med längre kolkedjor, utbytet för kvantifierbara ämnen i denna analys låg mellan 22,6 % - 140,5 % . Analysen av diPAPS och triPAPS gav inga haltdata på grund av lågt utbyte på 2,3 % – 4,3 % orsakat av bruseffekter samt metodens sämre förmåga att extrahera dessa ämnen från popcorn. Ur hälsosynpunkt utgör inte micropopcorn i sig självt någon risk då stora mängder behövs konsumeras för att uppnå de få gränsvärden som finns för de detekterade ämnena. Konsumtion av micropopcorn kan dock anses som en bidragande källa till förhöjda halter av PFAS i mänskligt blod.