Indiana University-Purdue University Indianapolis (IUPUI) / Perfluorooctanoic acid (PFOA) is a synthetic organic chemical that consists of an 8 carbon alkyl chain with a terminal carboxyl group in which the carbon-hydrogen bonds have been replaced with carbon-fluorine bonds except at the terminal carboxyl end. This perfluoralkyl carboxylate is a contemporary synthetic chemical that does not occur naturally in the environment and has only seen widespread use within the last 50 years. PFOA is environmentally persistent and is ubiquitously found in human serum. PFOA has been shown to induce a tumor triad consisting of liver adenomas, Leydig cell adenomas and pancreatic acinar cell tumors in male Spraque-Dawley rats. The ability of PFOA to produce tumors in rodents compounded by the fact that PFOA is accumulating not only in those occupationally exposed, but also in the general population, justifies concern about the carcinogenic potential of PFOA in humans. This paper reviews the data from current published research and reveals that some carcinogenic pathways identified in the tumors produced by PFOA in experimental animals may provide a plausible mode of action for human carcinogenesis.

Water contamination through substances called per- and polyfluoroalkyl substances (PFAS) is a worldwide problem. Being able to measure the concentrations of PFAS in water is a first step towards beating this contamination. One alternative is to use a field test kit instead of extensive lab equipment to monitor the contaminated areas. This thesis has investigated the possibility of using amine-functionalized mesoporous carbon as adsorbent to develop a detection method based on adsorbing first PFAS and then dye in aqueous solutions. The non-adsorbed dye concentrations are depending on the amount of PFAS, and hence the colour intensity in the remaining solution is proportional to PFAS concentration. Mesoporous carbon with amine functional groups were chosen as specific adsorbents for PFAS because of its large surface area and high adsorption capacity. It has been shown that some colorants would react in a similar way as PFAS on sorbents and thus can be used as an indicator for the user. In the study, the two most common PFAS, PFOA and PFOS, were studied and Rose Bengal was the dye. The adsorbent’s morphology, pore structure and pore size was verified with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen sorption before being tested. Adsorption tests were performed using different PFAS concentrations and a dye solution range in order to find three things: the detection range, the ratio powder/solution in order to see a difference, and the adsorption or saturation time for both PFAS and dye. This thesis concluded that even though the adsorbent was not as efficient as predicted, this method could be used for detecting PFAS concentrations down to at least 0.1 pg/ml and could be a possible approach for quick field tests in the future.

The recent expansion in chemical and manufacturing and innovation has led to a large influx of chemicals to the market, and subsequent release into the environment. Many of these new chemicals, as well as legacy chemicals are untested for their potential developmental toxicity, especially in early embryonic stages. This creates a need for a timely and cost-effective method for screening these chemicals. Furthermore, advances in in vitro methods and human pluripotent cell culturing techniques have revealed some weaknesses in our current animal model-based paradigms. Here we tested an in vitro model for developmental toxicity screening using human embryonic stem cells (hESCs) for environmental chemicals. In this study, hESCs were exposed to three known developmental toxicants that are prevalent in the environment, bisphenol A (BPA), perfluorooctane sulfonate (PFOS), or lead chloride (PbCl₂), at environmentally relevant concentrations of 0-2500 µg/L, 0-2275 µg/L, and 0-6200 µg/L respectively, for 6-days. hESCs were evaluated for dose responses on proliferation level by assaying cell viability, mitochondrial dehydrogenase activity (MDHA), cell confluency, and cell cycle distribution. Differentiation capability was assayed by induction of differentiation into ectoderm, mesoderm, and endoderm; hESCs and differentiated cells were then sequenced for their full transcriptome. Gene expression effects were analyzed by a single cell transcriptome sequencing and analysis of global DNA methylation. Proliferation and methylation effects were tested for all 3 chemicals, while differentiation and single cell sequencing was only tested on PbCl₂. Our results show hESCs were able to identify known and novel proliferation effects of BPA, PFOS, and PbCl₂, reflect differentiation level effects of PbCl₂, and elucidate molecular level drivers of these toxic effects. We also showed that hESCs responded to developmental toxicants at lower doses than in vivo models. In conclusion, our hESC-based model could act as an effective developmental toxicity screening tool for pre- peri- and post-implantation stages of embryo development.

Närvaron av PFAS (per- och polyfluorerade alkylsubstanser) i miljön och i vårt dricksvatten blir alltmer uppmärksammad i Sverige och världen. Denna undersökning gick dels ut på att undersöka föroreningssituationen av bland annat PFAS på brandövningsplatsen i Vetlanda enligt Naturvårdsverkets metodik för inventering av förorenade områden (MIFO) fas 2 och utfördes av Njudung Energi på uppdrag av Höglandets räddningstjänstförbund och Vetlanda kommun. En andra del utgjordes av ett laborationsförsök där reningskapaciteten för PFAS med fyra olika adsorbenter jämfördes. Vetlanda brandövningsplats påvisade kraftigt förhöjda halter PFOS (perfluoroktansulfonsyra) och ∑PFAS11 i grundvatten (8,9 µg/l och 27,2 µg/l respektive) och i jord (0,82 mg/kg TS PFOS). Halten PFOS i grundvatten var över 45 ng/l och i jord översteg halten 0,02 mg/kg TS som är SGI:s preliminära riktvärden för PFOS (Pettersson et al. 2015). I ytvattenrecipienten var halten PFOS över det rekommenderade årsmedelvärdet enligt EU:s miljökvalitetsnorm för inlandsvatten (65 ng/l). Ytvattenrecipienten anses särskild skyddsvärd då den mynnar ut i Emån, som har höga naturvärden och används som vattentäkt. Halten koppar och bly i jord översteg Naturvårdsverkets generella riktvärden för mindre känslig markanvändning (200 mg/kg TS och 400 mg/kg TS respektive). Objektet Vetlanda brandövningsplats bedöms utgöra riskklass 1 enligt MIFO fas 2, vilket innebär en mycket stor risk. Som åtgärd föreslås grundvattenpumpning och behandling för att åtgärda föroreningsnivån med avseende på PFAS i grundvattnet, fortsatt provtagning för att avgränsa föroreningen i jord samt schaktsanering av de förorenade jordmassorna för att förhindra fortsatt urlakning till grundvattnet. I laborationsförsöket jämfördes de två konventionella filtermaterialen granulärt aktivt kol (GAC) och jonbytarmassa (AE) med grillkol och torv, två relativt billiga material. Labbförsöket utfördes som ett kolonnförsök med varierande pH-värden samt som ett försök med förlängd exponeringstid. Resultatet visar att AE och torv gynnas av ett sänkt pH-värde och av en förlängd exponeringstid. GAC uppvisade bäst reningsgrad under samtliga försök, med fullständig adsorption av PFOS och ∑PFAS11 för kolonnförsöken. Torv avlägsnade 65% PFOS vid 10 dagars exponeringstid och grillkol avlägsnade omkring 50% PFOS i kolonnförsöken. Försöket innehåller endast ett fåtal provtagningspunkter och ytterligare studier med grillkol och torv krävs för att fastställa deras eventuella potential som adsorbenter för att rena PFAS i grundvatten.

Water pollution is a profound ecological concern, exerting detrimental effects on human well-being, ecological systems, and animal life. Among the emerging contaminants that critically influence water quality and have garnered substantial scientific interest in recent times are per- and polyfluoroalkyl substances (PFAS). It is crucial to investigate the de- velopment of an easy technique for PFAS detection and measurement that can be used for quick analysis. This thesis explores the possibility to use amine-functionalized mesoporous carbon as an adsorbent to develop a detection method based on sequential adsorption of per- and polyfluoroalkyl substances (PFAS) and a dye, Rose Bengal, onto the adsorbent. The hypothesis is that the concentration of non-adsorbed dye is dependent on the amount of PFAS present, making the color intensity of the remaining solution proportional to the PFAS concentration. Mesoporous carbon was chosen as the adsorbent due to their high specific surface area, providing a high adsorption capacity, and the potential to functionalize the surface with amine groups which will attract the PFAS. Rose Bengal was selected as a concentration indicator as it has been shown that it can be used as a proxy for PFAS. In this study, the most prevalent PFAS compounds, namely PFOA and PFOS, were investigated. Prior to testing, the adsorbent underwent characterization using diverse techniques to show the porosity and particle morphology. The adsorption experiments encompassed varying PFAS concentrations and a range of dye solutions to determine the detection range, the powder-to-solution ratio necessary for discernible differentiation, and the adsorption or saturation time for both PFAS and dye. This thesis concludes that it was not possible to detect neither PFOA nor PFOS in the range of 0.1 pg/mL to 1 μg/mL with the setup, even though Rose Bengal adsorption could be detected down to 0.6 μg/mL. It was further observed that amine-functionalized hard templated mesoporous carbon has a higher adsorption capacity compared to the soft templated material.

This thesis work aims to develop electrochemical sensors for sub-ppb level detection of inorganic and organic pollutants in drinking water with environmentally benign materials and processes. While traditional laboratory-based methods such as mass spectroscopy, and chromatography have been used to analyze the concentration of contaminants in drinking water, miniaturized electrochemical sensors offer a compelling alternative to those methods, enabling rapid on-site cost-effective detection of low concentrations of pollutants. In this research, a set of three-electrode sensors was designed and fabricated on a flexible substrate using a screen-printing technique. Additionally, an in-situ electrochlorination process was implemented to create the reference electrode. These sensors were utilized to precisely detect lead ions and perfluorooctane sulfonate (PFOS) in drinking water. The first set of sensors was fabricated to measure the concentration of lead ions, a toxic inorganic pollutant, in potable water. The novelty of the proposed research lies in using non-toxic, biodegradable sodium alginate grafted with 2- acrylamido-2-methyl propane sulfonic acid (AMPS) and conductive fillers for trace-level lead ion detection in water. The principle of square wave anodic square wave stripping voltammetry (SWASV) was used to determine the trace level lead ion concentration. Employing a similar approach with a different material, a PFOS sensor was developed. Utilizing chitosan, one of the sustainable and biodegradable biopolymers found in crustacean shells, rapid parts-per-trillion (ppt) level PFOS detection by electrochemical impedance spectroscopy (EIS) was demonstrated. The proposed sensors made low-cost electrochemical detection of contaminants such as lead ions and PFOS possible with eco-friendly materials and processes.

Per and polyfluoroalkyl substances (PFAS) are found ubiquitously in the environment across the globe.These substances have high persistence due to the strong carbon and fluorine bond. In the aquaticenvironment, due to high persistence, these substances don’t decay easily and are detected on the surfaceas well as in groundwater sources. Human exposure to PFAS has been observed due to ingestion of PFAScontaminated food and water which has an adverse effect on the human health. High concentrations ofPerfluoroalkyl Octanoic Sulphonate (PFOS) and Perfluoroalkyl Hexanoic Sulphonate (PFHxS) wereobserved in Lake Ekoln. The main aim of this study was to analyze the spread of PFOS and PFHxS in thelake. Hydrodynamic modelling of flow and water quality modelling in the lake was performed usingMIKE 3 FM software for the evaluation of the spread pattern of PFOS and PFHxS in the lake. Twoscenarios with the different mass fluxes of PFOS and PFHxS for Fyrisån were assumed for investigatingthe uncertainties and influence of contribution from Fyrisån. Additionally, conductivity from differentinflows was modelled as a passive tracer for understanding the water quality and the circulation in thelake. The results of the simulation showed that Fyrisån and Kungsängsverket are major contributors of PFOSand PFHxS to the lake. Similarly, the analysis of the current spread of PFOS and PFHxS shows that theuncertainty in the model is high and is dependent mainly on the assumption of mass flux from theFyrisån. Due to the lack of sampling data on the concentration of PFOS and PFHxS, it was difficult to geta reliable assumption for the mass flux from the Fyrisån. From the study, it was identified that thesampled concentration of PFOS and PFHxS also had certain variations which might be due to theinfluence of concentration from different sources and processes. Likewise, the simulation result of PFOSand PFHxS was observed to have a similar pattern of spread. Although PFOS is a long-chain PFAS andPFHxS is a short-chain PFAS and they have different physio-chemical properties, the spread patternswere observed to be similar. As only the hydrodynamic processes were influencing the simulation for thespread of PFOS and PFHxS in the lake and other physiochemical processes such as sedimentation andbioaccumulation were not included in the model, the simulated PFAS results were found similar. To conclude, the study shows that the spread of PFOS and PFHxS is mainly influenced by the flow andconcentration in Fyrisån. Also, higher uncertainty in the model performance was observed due to theissue of reliable mass flux estimation from Fyrisån. Similarly, the influence of processes such assedimentation and bio accumulation are necessary to be included in the model for analysis of spread ofPFAS with different physio-chemical properties.

The Methodology for inventory of contaminated sites (MIFO) is a method designed by the Swedish Environmental Protection Agency with an aim to facilitate agents and consultants during inventory of contaminated areas. It is structured into two stages, the first phase comprises oriented studies of the area while the second one consists of conceptual studies, such as field testing and analysis. After each phase the object is assigned a risk class that describes the degree of contamination and the risk associated with it. At Sundsvall-Timrå airport, the soil, surface- and groundwater at two fire drilling sites are contaminated with the anthropogenic substance PFOS, a former supplement in extinguishing foam. As a result of this, a number of environmental investigations have occurred over the past seven years which has led to a substantial amount of data in regards to the degree and dispersion of the contamination. However, prior to this date no risk classification according to MIFO phase 2 has been done. In order to appropriately remediate the site, it is essential that this step of the process is completed. Thus the County Administrative Board of Västernorrland in Sweden commissioned this thesis for the purpose of risk classifying Sundsvall-Timrå Airport. This was done by analysing the results from previous environmental investigations made by WSP Environmental and comparing them to the Swedish Geological Institute’s preliminary benchmark value for PFOS. The fact that Sundsvall-Timrå airport is situated in close approximation to a nature reserve and due to the high degree of contamination together with the substance distribution capabilities and high toxicity, the study resulted in the object being assigned risk class 1, very high risk. / Syftet med detta självständiga arbete var att på uppdrag av Länsstyrelsen i Västernorrland göra en MIFO fas 2 riskklassning av ett förorenat område vid Sundsvall-Timrå flygplats. MIFO (Metodik för inventering av förorenade områden) är en metodik framtagen av Naturvårdsverket med ändamålet att vägleda ombud och konsulter vid inventeringar av förorenade områden. Metoden är uppdelad i två steg, fas 1 och fas 2. Den första fasen involverar orienterade studier av området och den andra består av översiktliga studier, som till exempel fältundersökningar och analyser. Efter var fas tilldelas objektet en riskklass utifrån hur allvarlig föroreningssituationen bedöms vara. På Sundsvall-Timrå flygplats är marken, yt- och grundvattnet vid två brandövningsplatser förorenat med det antropogena ämnet PFOS som brukade ingå i släckskum. Som följd till detta har ett flertal miljötekniska mark- och grundvattenundersökningar gjorts i området under de senaste sju åren. Detta har lett till ett betydande underlag av data beträffande halt och spridning av föroreningen men fram tills nu har ingen fas 2 riskklassning av brandövningsplatserna med avseende på PFOS gjorts. Avsikten med arbetet var således att med hjälp av resultaten från tidigare miljötekniska undersökningar och SGIs preliminära riktvärden för PFOS, tilldela objektet en riskklass. Då Sundsvall-Timrå flygplats ligger intill Indalsälvens naturreservat, föroreningsnivån vid brandövningsplatserna anses vara mycket stor samt det faktum att PFOS har höga spridningsförutsättningar och toxicitet, resulterade studien i att området tilldelades riskklass 1, vilket innebär mycket stor risk.

Per- and polyfluoroalkyl substances (PFASs) are a group of toxic and persistent organic compounds. Their properties make them extremely resistant and they have been shown to have bioaccumulation and toxic properties in the environment and also to biomagnify in both aquatic and terrestrial food webs. This study has analysed different PFASs in African Darter (Anhinga rufa) eggs from five sites along Vaal River; Orange River, South Africa. Sixteen of 23 analysed PFASs were detected and quantified, and the homologue profiles were studied from all five sites. Total perfluorooctane sulfonic acid (PFOS) (all structural isomers) was the predominated compound of all PFASs, accounting for 88-98% for all sites, with a median concentration range of 58 ng/g ww to 2473 ng/g ww. The second highest concentration was found for perfluorodecanoic acid (PFDA) (1.9-42 ng/g ww), followed by perfluorononanoic acid (PFNA) (1.1-14 ng/g ww) and perfluorohexane sulfonate (PFHxS) (0.68-6.0 ng/g ww). The results showed significantly that the three up-stream sites (Welverdiend, Schoemansdrift and Orkney East) had similar patterns and that eggs from Schoemansdrift had the highest levels of PFASs. This may indicate the same source of origin for these three sites and that Schoemansdrift are closest to the contamination source. The three sites (Welverdiend, Schoemansdrift and Orkney East) with similar pattern is closest to Gauteng, which can be where the emission source is located, because it is an industrial area. Perfluoroalkyl carboxylic acids (PFCAs) and PFOS might originate from different sources and the source for PFCAs could be degradation of fluorotelomer-based precursors. Structural isomer profiles of PFOS showed similar results as the PFAS homologue patterns, which give further indication of the source of origin. The contribution of linear PFOS (L-PFOS) to the total amount of PFOS was between the range of 94 and 97%. Bloemhof had the highest concentration of branched isomers among all sites. The L-PFOS concentrations in Bloemhof were also significantly differ from Schoemansdrift. This indicate two different sources between Bloemhof and the three up-steam sites, or an effect of environmental fractionation.

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.