Societies are facing great challenges with obtaining a good quality and quantity of drinking water in the context of climate change. Increases in natural organic matter (NOM) and per- and polyfluoroalkyl substances (PFAS) have been observed in lakes and drinking water the past years, which is of great concern for water treatment plants in Sweden. It is therefore vital to increase the knowledge regarding the distribution of these substances in the environment. The main objective of this project was therefore to further develop a hydrodynamic model for lake Ekoln by including transportation and degradation of NOM. This was to be done by calibrating the model in terms of total organic carbon (TOC) and Water colour (Colour). A second objective was to investigate the requirements to successfully model PFAS in Ekoln for future studies. The study was done using the model MIKE 3 FM, developed by the Danish Hydraulic Institute (DHI) The two variables TOC and Colour, were calibrated separately for the period of February 2017 to September 2018. For TOC the within-lake processes were decay and sedimentation. These were described using a reference decay constant for 20 °C (k0), that was scaled using the Arrhenius temperature coefficient (θ), and sedimentation was represented by a settling velocity (vsm). For Colour the included process was photooxidation. This process was described using a maximum photooxidation rate (kphoto) that was scaled using the Monod relation including parameters for minimum photosynthetically active radiation (PAR) necessary for photooxidation to occur (Imin) and a PAR half saturation constant (I1/2). The calibration of TOC resulted in the following best fit parameters for k0  of 0.001 d-1, θ of 1.07 and vsm of 0.001 md-1. The calibration of Colour resulted in the following best fit parameters for kphoto of 0.0125 d-1, Imin of 0 µmol photons m-2s-1 and I1/2 of 4 µmol photons m-2s-1. Overall it can be concluded that the chosen processes managed to capture the seasonal variations of TOC and Colour, and the calibrated parameter values are in line with similar studies. The assumption of not including autochthonous input proved to be the biggest source of error in the calibration of TOC but proved to have a minor influence on the calibration of Colour. To achieve a more realistic representation of photooxidation in the vertical profile, for the simulation of Colour, more processes should be considered to be added in the model in future studies. The results presented in this study contributes with increased knowledge of carbon budgets in lakes and can be used to predict water quality hazards connected to climate change and extreme events. The limited access to PFAS data for Ekoln, constrained the study of PFAS and only two sources could therefore be studied: The sewage treatment plant Kungsängsverket and precipitation. The results showed that the simulated concentrations of PFAS in Ekoln only accounted for 40 % of the observed concentrations. It could further be concluded that the contribution from precipitation is negligible. For future studies it is judged to be vital to include Fyrisån as a PFAS source, and to look into processes that influence PFAS distribution, such as sedimentation and adsorption to organic matter. / Samhällen står idag inför stora utmaningar vad gäller att tillhandahålla god kvalitet och kvantitet av dricksvatten under rådande klimatförändringar. De senaste åren har det observerats ökande halter av naturligt organiskt material (NOM) och per- och polyfluorerade alkylsubstanser (PFAS) i sjöar och dricksvatten, vilket är bekymmersamt för Sveriges vattenreningsverk. Det är därför av största vikt att öka kunskapen om dessa ämnens distribution i miljön. Huvudsyftet med denna studie var därför att vidareutveckla en hydrodynamisk modell för sjön Ekoln så att den även inkluderar transporten och nedbrytningen av NOM. Detta utfördes genom att kalibrera modellen för totalt organisk kol (TOC) och Vattenfärg (Färg). Ett andra syfte var att undersöka vilka förutsättningar som krävs för att kunna modellera PFAS på ett korrekt sätt i Ekoln. Studien utfördes i modellverktyget MIKE 3 FM, utvecklat av DHI.  De två variablerna TOC och Färg kalibrerades separat för perioden februari 2017 – september 2018. Processerna som valdes att påverka TOC var nedbrytning och sedimentation. Dessa processer beskrevs med hjälp av en referens-nedbrytningskonstant för 20 °C (k0), vilken anpassades med hjälp av Arrhenius temperaturkoefficient (θ) och sedimentation beskrevs med hjälp av en sedimentationshastighet (vsm). Färg påverkades endast av processen fotooxidation vilken beskrevs med en maximal hastighet för fotooxidation  (kphoto) som anpassades med hjälp av Monods relation. Anpassningen skedde med hjälp av parametern för minimal fotosyntetiskt aktivt ljus (PAR) för att fotooxidation ska ske (Imin) samt en PAR halv mättnads konstant (I1/2) .  Kalibreringen resulterade i värden för k0 av 0.001 d-1, θ av 1.07 och vsm av 0.001 md-1. Kalibreringen för Färg resulterade i värden för kphoto av 0.0125 d-1, Imin av 0 µmol fotoner m-2s-1 och I1/2 av 4 µmol fotoner m-2s-1. Det kan konstateras att de valda processerna lyckas med att beskriva säsongsvariationerna av både TOC och Färg och att de kalibrerade parametervärdena stämmer överens med litteraturen. Antagandet om att inte inkludera autoktont tillförsel av organiskt material (NOM från ytvatten), visade sig vara den största felkällan i simulering av TOC, men visade sig ha en mycket liten påverkan på simuleringen av Färg. För en mer realistisk bild av fotooxidations spridning i djupled, för simuleringen av Färg, bör fler processer övervägas att inkluderas i modellen för framtida studier.  Studien av PFAS var begränsad av tillgången till data, vilket medförde att endast två källor av PFAS till Ekoln analyserades: reningsverket Kungsängsverket och nederbörd. Resultaten visade att den simulerade koncentrationen av PFAS endast motsvarade 40 % av den observerade. Vidare kunde det konstateras att tillförsel av PFAS från regn kan antas vara försumbar. För framtida studier av PFAS i Ekoln bedöms det vara avgörande att inkludera Fyrisån som en källa, samt att vidare undersöka processer som påverkar transporten av PFAS så som sedimentation och adsorption till organiskt material.

Avloppsreningsverk utgör en viktig spridningsväg för läkemedelsrester till den akvatiska miljön. Även per- och polyfluorerade alkylsubstanser (PFAS) har påvisats i utgående vatten från avloppsreningsverk. För att minska utsläpp av dessa krävs ett kompletterande reningssteg. Syftet med denna studie var att utvärdera utökad rening av avloppsvatten med granulerat aktivt kol (GAK) och anjonbytare (AIX, Anion exchange resin). Underlag för utvärdering utgjordes av resultat från pågående pilotstudie vid Kungsängsverket i Uppsala, vilken består av kolonnförsök samt pilotförsök i större skala. I kolonnförsöken testas kombinationen GAK (Cyclecarb 401 eller Filtrasorb 400) i fixerade bäddar, följt av AIX (Purolite 694E) i fixerade samt fluidiserade bäddar i olika driftlinjer. Kontakttiden (EBCT, Empty Bed Contact Time) var cirka 15 minuter för GAK respektive 5 minuter för AIX. I pilotförsöken inkluderas även tvåstegsdrift av GAK med EBCT på cirka 14 minuter per filter. Vid slutet av denna studie hade cirka 36 000 till 37 000 bäddvolymer (BV) behandlats med GAK, respektive 98 000 till 116 000 BV med AIX i kolonnförsöken. I pilotförsöken hade cirka 5 000 till 10 000 BV behandlats med GAK samt cirka 8 000 till 31 000 BV med AIX. Reningseffektivitet utvärderades avseende avskiljning av diklofenak, oxazepam, metoprolol, citalopram samt PFOS eftersom dessa i tidigare studie pekats ut som mest utmanande för mottagande vattenmiljö. En högre avskiljning av oxazepam, metoprolol och citalopram uppnåddes med GAK än med AIX, där Cyclecarb 401 uppvisat högst reduktion. För diklofenak och PFOS uppnåddes en högre avskiljning med kombinationen GAK följt av AIX än med enbart GAK. Driftkostnad och klimatpåverkan utvärderades för samtliga adsorbenter samt för specifika scenarion vid Kungsängsverket. Scenarierna inkluderar olika reningsmål för avancerad rening med singel- respektive tvåstegsdrift av GAK samt GAK följt av AIX. Reningsmålen avser en 80 procentig genomsnittlig reduktion över tid av diklofenak, oxazepam, PFOS eller en kombination av dessa. Vid ekvivalent dos av adsorbenterna resulterade Cyclecarb 401 i den lägsta driftkostnaden och klimatpåverkan. Lägst driftkostnad för samtliga reningsmål erhölls med tvåstegsdrift av GAK. För avskiljning av PFOS eller PFOS och diklofenak erhölls lägst klimatpåverkan med kombinationen GAK följt av AIX. För resterande reningsmål erhölls lägst klimatpåverkan med tvåstegsdrift av GAK. I tillägg utfördes en regressionsanalys för att undersöka om enkla mätningar av löst organiskt kol (DOC) eller ultraviolett absorbans (UVA) kan användas som uppföljningsmetod för reningseffektiviteten. Ingen korrelation kunde dock fastställas mellan skillnaden i ingående och utgående koncentration eller absorbans av DOC, UVA och diklofenak, oxazepam eller PFOS. / Wastewater treatment plants are an important source for the spread of pharmaceuticals to the aquatic environment. Per- and polyfluorinated alkyl substances (PFASs) have also been detected in outgoing wastewater. To reduce emissions of these micropollutants, an advanced treatment process is required.  This study aimed to evaluate advanced treatment with granular activated carbon (GAC) and anion exchange resin (AIX), using results from an ongoing pilot study at the wastewater treatment plant Kungsängsverket in Uppsala, Sweden. The pilot study consists of column tests and pilot tests in larger scale. The column tests consist of the combination of GAC (Cyclecarb 401 or Filtrasorb 400) in fixed beds, followed by AIX (Purolite 694E) in fixed or fluidized beds in different operating lines. Contact time (EBCT, Empty Bed Contact Time) was 15 minutes for GAC and 5 minutes for AIX. The pilot tests include two-stage operation of GAC with EBCT of 14 minutes per filter. At the end of this study, in the column tests, approximately 36 000 bed volumes (BV) had been treated with GAC and 98 000 to 116 000 BV with AIX. In the pilot tests, 5 000 to 10 000 BV had been treated with GAC and 8 000 to 31 000 BV with AIX. Treatment efficiency was evaluated for diclofenac, oxazepam, metoprolol, citalopram and PFOS, since these were identified as prioritized substances in a previous study. A higher reduction of oxazepam, metoprolol and citalopram were obtained using GAC compared to AIX, where Cyclecarb 401 showed the highest reduction. For diclofenac and PFOS, a higher reduction was achieved for the combination of GAC followed by AIX compared to GAC alone.  Operating cost and climate impact were evaluated for the adsorbents as well as for specific scenarios at Kungsängsverket, that includes different treatment goals for single stage and two-stage operation of GAC, and GAC followed by AIX. Treatment goals consists of an 80 percent average reduction over time of diclofenac, oxazepam, PFOS, or a combination of these. For an equivalent dose of adsorbent, the lowest operating cost and climate impact was obtained with Cyclecarb 401. The lowest operating cost for all the treatment goals was obtained with two-stage operation of GAC. For reduction of PFOS or PFOS and diclofenac, the lowest climate impact was obtained with the combination of GAC followed by AIX. For the remaining treatment goals, the lowest climate impact was obtained with two-stage operation of GAC.   In addition, a regression analysis was preformed to evaluate whether measurements of dissolved organic carbon (DOC) or ultraviolet absorbance (UVA) could serve as a prediction method for the treatment efficiency of organic micropollutants. However, the regression analysis showed no correlation between the reduction of DOC, UVA, and diclofenac, oxazepam or PFOS.

The growing concern around per- and polyfluoroalkyl substances (PFAS) and their negative health and environmental effects have lately become more apparent which also is reflected in the new, more strict regulations of permitted levels of PFAS in drinking water extracted from water resources. However, many point sources of PFAS pollution to the environment and to water resources are still not identified and assessed for risk. This is also the case around the Mälaren-Görväln which is used as a drinking water resource. Work has been initiated to map sources of PFAS pollution to the water resource. However, hitherto, the risk of PFAS pollution from landfills surrounding the water intake is under-studied. This thesis has thus tried to address the issue by investigating landfills’ potential PFAS contribution to Mälaren-Görväln water body. Active and inactive landfills which are located within the Östra Mälaren water protection area have been researched. Furthermore, field sampling and measurements of PFAS in surface water have been conducted in connection with three landfills within the water protection area and in Brobäcken. Data from the Högbytorp facility which incorporates three landfills has also been used for comparison. The PFAS load from the landfills to Mälaren-Görväln has been estimated. Lastly a principal component analysis (PCA) has been carried out to trace the sources of sampled PFAS levels. The research of landfills located within the water protection area, led to identification of 32 different landfills of which almost all are believed to be inactive. All field samples taken in connection to Skå, Svartsjö and Johannelund landfill indicated levels of PFAS. The levels detected were lower than the levels measured downstream Högbytorp and in Brobäcken. At all sampling locations, including downstream Högbytorp and excluding the sample by Svartsjö, the levels detected exceed at least one current guiding and soon to be limiting value. The estimated mass flows of PFAS received at the sampling locations showed that landfills can potentially account for a considerable share of the estimated loads to Mälaren-Görväln. However, the results should be interpreted with caution due to the small dataset analysed and as it proved to be difficult to determine specifically the landfills’ share of the PFAS concentrations detected as the other potential sources of PFAS can have an influence on the sampled surface water. It remains to carry out a more in-depth risk assessment of the landfills' potential impact on Mälaren-Görväln where, among other things, PFAS pollution to the soil and groundwater are included. Further, more research of all identified landfills is needed to estimate the cumulative potential impact of landfills’ PFAS load to Mälaren-Görväln and the extracted drinking water. / Det växande problemet kring per- och polyfluoralkylsubstanser (PFAS) och deras negativa hälso- och miljöeffekter har på senare tid blivit allt mer uppenbar. Angelägenheten återspeglas i nya och striktare regler för tillåtna halter av PFAS i dricksvatten som utvinns från vattenresurser. Flertalet punktkällor för PFAS-föroreningar som påverkar miljö och vattenresurser är varken identifierade eller riskbedömda. Så är även fallet för Mälaren-Görväln som används som en dricksvattenresurs. Visserligen har arbete inletts för att kartlägga källor av PFAS-föroreningar till Mälaren-Görväln. Däremot saknas undersökningar om risken för PFAS-förorening kring vattenresursen. I syfte att fylla föregående nämnda forskningsgap, syftar denna avhandling till att studera deponiers potentiella PFAS-bidrag till Mälaren-Görvälns vattenförekomst. Inom ramen för studien har både aktiva och inaktiva deponier inom Östra Mälarens vattenskyddsområde undersökts. Vidare har fältprovtagning och mätningar av PFAS i ytvatten genomförts i anslutning till tre deponier inom vattenskyddsområdet och i Brobäcken. Data från Högbytorps anläggning som innefattar tre deponier har även använts för jämförelse. PFAS-belastningen från de studerade deponierna till Mälaren-Görväln har uppskattats. Slutligen har en principalkomponentanalys (PCA) genomförts för att spåra källorna till provtagna PFAS-nivåer.  Undersökningen resulterade i identifiering av 32 olika deponier varav nästan alla tros vara inaktiva. Alla provtagningar som tagits i anslutning till deponierna Skå, Svartsjö och Johannelunds visar uppmätta halter av PFAS. De påvisade halterna var lägre än de halter som uppmätts nedströms Högbytorp och i Brobäcken. På alla provtagningsplatser, inklusive nedströms Högbytorp och exklusive provtagning vid Svartsjö, överstiger de påvisade halterna minst ett vägledande och framtida gränsvärde. De uppskattade massflödet av PFAS vid provtagningsplatserna visade att deponier potentiellt kan stå för en betydande andel av de beräknade belastningarna till Mälaren-Görväln. Resultaten bör dock tolkas med försiktighet på grund av den lilla datauppsättning som har analyserats och eftersom det visade sig vara svårt att specifikt bestämma deponiernas andel av de PFAS-koncentrationer som uppmätts. Andra potentiella PFAS källor i anslutning till deponierna kan ha en inverkan på de ytvatten som har provtagits i studien.   Framtida forskning bör utföra en mer djupgående riskbedömning av deponiers potentiella påverkan på Mälaren-Görväln där även PFAS-föroreningar till mark och grundvatten bör ingå. Avslutningsvis efterfrågas vidare undersökning av den kumulativa potentiella påverkan av deponiers PFAS-belastning på Mälaren-Görväln och det extraherade dricksvattnet.

Today there are many uncertainties in the form of a lack of knowledge about perfluorinated and polyfluorinated substances (PFAS) regarding long-term risks to health and the environment, there is no efficacy data for many environments. The fluorocarbon bond is the strongest chemical bond, which means that PFAS can be transported long distances, for example through water streams and into the atmosphere. If surface water and groundwater are contaminated by PFAS, people are at risk of exposure to PFAS through the drinking water. It is therefore important to investigate and identify what difficulties and opportunities the municipalities see in their work to influence and reduce the occurrence of PFAS in drinking water with PFAS in water revenues and drinking water. The purpose of the study is to map what Halmstad, Linköping and Uppsala municipality see for difficulties and opportunities in their work on influencing and reducing the occurrence of PFAS in drinking water and how the result relates to scientific research about national environmental management. We have chosen to do a qualitative interview with an analysis of the interview using previous research on national environmental management about actions, cooperation and policy, directives, guidelines, and legislation. Some of the conclusions the study came to where that the municipalities see similar difficulties and opportunities in working with PFAS and have similar ways of working with PFAS. But there are still some differences and similarities in what they see for difficulties and opportunities in their work with PFAS. Difficulties that have been identified are inadequate or unclear guidelines, directives, legislation and insufficient limit values. It is also a difficulty that the municipalities do not know where all sources of PFAS pollution come from. Opportunities that have been identified are collaborations, knowing where certain parts of PFAS's pollution come from. One possibility that exists is to influence certain polluting activities by means of distribution routes, to submit activities to improve purification methods and to set requirements for sampling and remediation. / Det finns idag många osäkerheter i form av bristande kunskap om perfluorerade och polyfluorerade ämnen (PFAS) när det gäller långsiktiga risker mot hälsa och miljö, det saknas effektdata för många miljöer. Fluor-kol-bindningen är den starkaste kemiska bindningen vilket leder till att PFAS kan transporteras långa vägar, genom till exempel vattenströmmar och i atmosfären. Om ytvatten och grundvatten blir förorenat av PFAS så riskerar människor att exponeras för PFAS genom dricksvattnet. Det är därför av vikt att undersöka och identifiera vad för svårigheter och möjligheter kommunerna ser med sitt arbete med att påverka och minska förekomsten av PFAS i dricksvatten med PFAS i vattentäkter och dricksvatten. Syftet med studien är att kartlägga vad Halmstad, Linköping och Uppsala kommun, ser för svårigheter och möjligheter i sitt arbete med att påverka och minska förekomsten av PFAS i dricksvatten och hur resultatet förhåller sig till vetenskaplig forskning om nationell miljömanagement. Vi har valt att göra en kvalitativ intervju med en analys av intervjun med hjälp av tidigare forskning om nationell miljömanagement med avseende på åtgärder, samarbete och direktiv, riktlinjer och lagstiftning. Några av slutsatserna studien kom fram till var att kommunerna ser liknande svårigheter och möjligheter i arbetet med PFAS och har liknande sätt att arbeta med PFAS på. Men det finns ändå en del skillnader och likheter i vad de ser för svårigheter och möjligheter i deras arbete med PFAS. Svårigheter som har identifierats är otillräckliga eller otydliga riktlinjer, direktiv, lagstiftning och otillräckliga gränsvärden. Det är även en svårighet att kommunerna inte vet vart alla källor av PFAS-föroreningar kommer från. Möjligheter som har identifierats är samarbeten, att veta vart vissa delar av PFAS föroreningar kommer från. En möjlighet som finns är att påverka vissa förorenande verksamheter genom spridningsvägar, förelägga verksamheter att förbättra reningsmetoder och sätta krav på provtagning och sanering.

Background: Prenatal exposure to perfluoroalkyl substances (PFAS) has been associated with lower birth weight in epidemiologic studies. This association could be attributable to glomerular filtration rate (GFR), which is related to PFAS concentration and birth weight. Objectives: We used a physiologically based pharmacokinetic (PBPK) model of pregnancy to assess how much of the PFAS–birth weight association observed in epidemiologic studies might be attributable to GFR. Methods: We modified a PBPK model to reflect the association of GFR with birth weight (estimated from three studies of GFR and birth weight) and used it to simulate PFAS concentrations in maternal and cord plasma. The model was run 250,000 times, with variation in parameters, to simulate a population. Simulated data were analyzed to evaluate the association between PFAS levels and birth weight due to GFR. We compared simulated estimates with those from a meta-analysis of epidemiologic data. Results: The reduction in birth weight for each 1-ng/mL increase in simulated cord plasma for perfluorooctane sulfonate (PFOS) was 2.72 g (95% CI: –3.40, –2.04), and for perfluorooctanoic acid (PFOA) was 7.13 g (95% CI: –8.46, –5.80); results based on maternal plasma at term were similar. Results were sensitive to variations in PFAS level distributions and the strength of the GFR–birth weight association. In comparison, our meta-analysis of epidemiologic studies suggested that each 1-ng/mL increase in prenatal PFOS and PFOA levels was associated with 5.00 g (95% CI: –21.66, –7.78) and 14.72 g (95% CI: –8.92, –1.09) reductions in birth weight, respectively. Conclusion: Results of our simulations suggest that a substantial proportion of the association between prenatal PFAS and birth weight may be attributable to confounding by GFR and that confounding by GFR may be more important in studies with sample collection later in pregnancy.

Perfluoroalkyl substances (PFASs) are contaminants of emerging concern, and have been detected in drinking water, wildlife, humans, and the environment. Cyclodextrins (CDs), cyclic sugars composed of glucose monomers, are proposed as a potential remediation strategy. CDs can form host-guest complexes with hydrophobic molecules; this complexation could be capitalized on for PFAS removal and sequestration. These dissertation projects aim to study the fundamental host-guest interactions between a variety of PFASs and CDs for eventual applications in environmental and biological remediation. 1D and 2D Nuclear magnetic resonance (NMR) spectroscopic methods were employed to determine the strength, dynamics, and structure of the CD:PFAS host-guest complexes. Legacy and emerging PFASs were studied with the three native CDs (α-, β-, and γ-CDs) as well as β-CD derivatives. β-CD and its derivatives exhibit the strongest complexation with all studied PFASs, with association constants of 102-105 M-1, depending on PFAS chain length, functional groups, and branching. The host-guest complex was not significantly disturbed under different environmental conditions, such as changing pH, ionic strength, and in the presence of humic acid. A competition study between perfluorooctanoic acid (PFOA), β-CD, and human serum albumin (HSA), the most abundant protein in blood serum, was then conducted using NMR, circular dichroism, and fluorescence spectroscopies. Excess β-CD was able to totally reverse all PFOA binding to HSA. Finally, the host-guest complex was studied within a biological organism to test its viability as a remediation strategy. The attenuation of the toxicity of PFOA in zebrafish embryos, a model organism for toxicology studies, was tested with β-CD. Excess β-CD increased the LC50 (lethal concentration for 50 % of the population) of PFOA compared to PFOA in the absence of β-CD (p < 0.0001). These dissertation projects suggest that the encapsulation of PFASs by CDs has potential in PFAS remediation strategies.

Perfluorerade alkylsyror (PFAS) är en grupp ämnen som de senaste åren har uppmärksammats för dess persistenta, bioackumulerande och toxiska egenskaper för människor och djur. Det är känt att brandövningsplatser där det filmbildande skummet AFFF har använts utgör betydande punktkällor för PFAS. Förutom att förorena marken vid brandövningsplatserna kan PFAS spridas med grundvattnet, vilket har orsakat förorenade dricksvattentäkter på ett flertal platser i Sverige. Hydrogeologiska modeller kan användas för att modellera grundvattnets flöden och medföljande föroreningar. Syftet med examensarbetet är att med en hydrogeologisk modell undersöka föroreningsspridning och transporttider av PFAS-ämnet perfluoroktansulfonat (PFOS) från en brandövningsplats till ytvatten och grundvattentäkter i Bredåkradeltat, väster om Kallinge i Blekinge. Den hydrogeologiska modellen skapades i Visual MODFLOW och transportmodelleringen gjordes med MT3D99 och MODPATH. Modellen kunde reproducera uppmätta grundvattennivåer, med en korrelationskoefficient (R) på 0,98 mellan modellerade och uppmätta nivåer. Med antagandet försumbar adsorption visade modellresultaten att en föroreningsplym med hög PFOS-koncentration (~90.000 ng/l) spreds från brandövningsplatsen till ett våtmarksområde väster om Klintabäcken, och vidare till dalen längs Klintabäcken med lägre koncentrationen (0–4.000 ng/l). Enligt modellen spreds dock inte föroreningen lika långt som uppmätta värden visar. När PFOS väl har nått Klintabäcken bedöms den kunna spridas snabbt med ytvattnet mot grundvattentäkterna, för att sedan infiltrera ned i isälvsmaterialet nära aktiva grundvattentäkter. Transporttiden av PFOS från brandövningsplatsen till Klintabäcken beräknades till sex år för den bäst kalibrerade modellen, vilket betyder att grundvattentäkterna kan ha varit förorenade sedan slutet av 1980-talet eller början av 1990-talet. Beräkningar av masstransport indikerar att runt 3,5 kg PFOS flödar genom Klintabäcken varje år, och att det mesta av den mängden kommer från området vid brandövningsplatsen. Trots förenklingar av Bredåkradeltats komplexa geologi och svårigheter att nå konvergens i modellen bedöms den kunna reproducera hydrogeologiska egenskaper inom deltat, samt föroreningsplymens spridning från brandövningsplatsen till Klintabäcken.

Per- and polyfluoroalkyl substances (PFASs) are man-made fluorinated compounds that havebeen detected in humans, the environment, and wildlife. The strong C-F bonds contribute tothe high thermal stability of some PFASs and make them extremely resistant to degradationunder normal environmental conditions. The commonly studied classes of PFASs areperfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids. Though the phase-out ofperfluorooctane sulfonic acid and perfluorooctanoic acid for some time, they were the mostfrequent compounds measured and detected in biota.In this study, the total oxidisable precursor (TOP) assay, which is a method used to indirectlymeasure and estimate PFAS precursors, was evaluated. Different parameters were studied tounderstand their effects on oxidation of precursor compounds following TOP assay method(e.g., oxidation rate, pH of the oxidation solution and different washing steps during solidphaseextraction)The results from this experiment showed that the target precursors were oxidised and part ofthe proportion of the compounds formed ranged from 37 to 100% (molar ratio). Whenperforming TOP assay, it was shown that some precursors oxidised before 0.5 h while otherprecursors were oxidised after 4 hours. However, it was still unknown what products wereformed when some precursors were oxidised e.g., 7:3 fluorotelomer carboxylic acid (7:3-FTCA) and 10:2 fluorotelomer unsaturated carboxylic acid (10:2- FTUCA) because of animbalance of precursors to degradation products (molar to molar ratio).When the washing steps for solid-phase extraction were evaluated for potential losses ofprecursors, it could be seen that the ammonium acetate and the 20% methanol in Milli-Q waterled to the loss of some precursors. These results showed precautions were needed wheninterpreting the results using TOP assay.

Per- and polyfluoroalkyl substances (PFAS) have been manufactured and used in differentapplications for several decades, including food packaging materials. During the last 20 yearsthese compounds have been acknowledged as hazardous for humans and the environment, anddifferent regulations on PFAS have been established on both national and international levels.Companies started to phase-out long-chain PFAS, including both PFOA and PFOS, around 20years ago. Since PFAS are persistent, this cause concerns both for our health and theenvironment, as well as possible PFAS contamination in new products due to the recycling ofmaterials. The aim of this study was to find an effective method to extract PFAS from differentfood packaging materials; analyze the samples for their extractable organofluorine (EOF)content using combustion ion chromatography; as well as analyze targeted PFAS in the samplesusing ultra-high performance liquid chromatography tandem mass spectrometry. The findingsof this study suggest that none of the selected samples had EOF contents above the Danishindicator value of 20 mg/kg dw TOF set to determine whether PFAS has been intentionallyadded to a material, and that only two samples exceeded the limit of detection for EOF. Atakeaway bowl made out of 100% sugarcane contained the highest EOF content while the outerpackaging of a cereal box contained the second highest EOF. Both PFOA and PFOS, alongwith other long-chain PFAS were detected in a majority of the samples. The lowest total PFASconcentrations when analyzing for targeted PFAS was detected in the sugarcane take awaybowl. The highest total PFAS concentration was detected in an egg carton, followed by theouter packaging of a cereal box (same as above) and the outer box of a waffle mix. The targetedPFAS was detected in almost all samples, with PFNA and 6:2 diPAP being the most frequentlydetected PFAS. PFCAs, PFSAs, FTSAs, FOSAAs and PAPs were detected in a majority of thesamples. The highest concentrations were measured for diSAmPAP in a majority of thesamples. Mass balance calculations of the sugarcane bowl showed that the targeted PFAS onlyaccounted for 0.04% of the extractable organofluorine content. In conclusion, none of thesamples displayed EOF contents higher than the Danish indicator value, suggesting that noneof the samples were intentionally treated with PFAS. However, targeted PFAS analysis of thesesamples showed that they still contain PFAS, that could be further recycled along with therecycling of paper and board food packaging materials. Considering the persistence of PFASand that these compounds can remain in the recycling chain, with the risk of also being releasedinto the environment, it is of importance that PFAS is not introduced in any of the stages in apaper or board containers life cycle.

Per- and polyfluoroalkyl substances (PFAS) are a class of man-made contaminants of increasing human health concern due to their resistance to degradation, widespread occurrence in the environment, bioaccumulation in human and animal organ tissue, and potential negative health impacts. Drinking water is suspected to be a primary source of human PFAS exposure, so the US Environmental Protection Agency (US EPA) has set interim and final health advisories for several PFAS species that are applicable to municipal water supplies. However, private drinking water supplies may be uniquely vulnerable to PFAS contamination, as these systems are not subject to EPA regulation and often include limited treatment prior to use for drinking or cooking. The goal of this study was to determine the incidence of PFAS contamination in private drinking water supplies in two counties in Southwest Virginia (Floyd and Roanoke), and to examine the potential for reliance on citizen-science based strategies for sample collection in subsequent broader sampling efforts. Samples for inorganic ions, bacteria, and PFAS analysis were collected on separate occasions by homeowners and experts at the home drinking water point of use (POU) in 10 Roanoke and 10 Floyd County homes for comparison. Experts also collected an outside tap PFAS sample. At least one PFAS compound was detected in 76% of POU samples collected (n=60), with an average total PFAS concentration of 23.5 parts per trillion (ppt). PFOA and PFOS, which are currently included in EPA health advisories, were detected in 13% and 22% of POU samples, respectively. Of the 31 PFAS species targeted, 15 were detected in at least one sample. On average, a single POU sample contained approximately 3 PFAS, and one sample contained as many as 8 different species, indicating that exposure to PFAS in complex mixtures is worth noting. Although there were significant differences in total PFAS concentrations between expert and homeowner collected samples (Wilcoxon, alpha = 0.05), it is unclear whether this difference was due to contamination by the collector or the water usage and time of day of sampling (i.e. morning, afternoon). It is worth noting that there was no significant difference in the number of PFAS species in the samples collected by homeowners and experts. Given the considerable variation in PFAS detections between homes, future studies reliant on homeowner collection of samples appears possible given proper training and instruction to collect at the same time of day (i.e. first thing in the morning). / Master of Science / Per- and polyfluoroalkyl substances (PFAS) belong to a large family of manmade compounds that are commonly used in a variety of household and consumer products due to their unique water and stain resistant properties. PFAS compounds are not easily broken down in the environment and have been detected globally in air, soil, and water samples. In addition to their environmental detections, PFAS are slow to be removed from the body after ingestion and known to cause negative health effects in concentrations less than one part per trillion. Drinking water is considered to a main source of PFAS consumption for humans; as such, the US Environmental Protection Agency (US EPA) has set strict, but not legally binding, interim and final health advisories (HA) for four types of PFAS. However, these health advisories only apply to public water services and do not cover private drinking water systems, such as wells or springs, which are the full responsibility of the well owner. Private drinking water system users often do not treat their water before drinking which may make these systems uniquely vulnerable to PFAS contamination. This study focused on 20 total homes, 10 in Roanoke County and 10 in Floyd County to see if PFAS was present and to determine whether or not homeowners would be able to collect their own samples for PFAS analysis at home as accurately as researchers or experts with proper instructions. Homeowners and experts collected drinking water samples inside at a point of use (POU), usually at a kitchen faucet, and outside of the home, usually from a tap. PFAS were present in 76% (n=60) of POU samples, with an average combined concentration of 23.5 parts per trillion (ppt). The two most well studied PFAS, PFOA and PFOS were detected in 13% and 22% of POU samples, respectively. It was also common to detect at least 3 PFAS in a single sample. Although there were differences in total average concentrations of PFAS in samples collected by homeowners and experts, variation could be caused by several factors indicating that with proper training and instruction it is likely future studies could still rely on homeowners to collect samples for PFAS analysis.