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Poly- and perfluoroalkyl substances (PFAS) are a chemical class of global concern because of their persistence, toxicity and widespread presence in the environment. This work aimed to develop a robust and reliable method to analyse perfluorohexane sulfonic acid (PFHxS), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), as well as the neutral volatile PFOS precursors, namely perfluorooctane sulfonamides and perfluorooctane sulfonamidoethanols (FOSAs/FOSEs). Because these compounds can be distributed globally through atmospheric long-range transport, air sampling materials, such as polyurethane foam (PUF) or styrene-divinylbenzene resin (XAD) sorbents are used to capture them. Parameters optimised were extraction solvents, solid phase extraction (SPE) as clean-up and instrumental parameters of the utilised ultra-performance liquid chromatograph tandem mass spectrometer (UPLC-MS/MS) with electron spray ionisation (ESI). The resulting method consisted of Soxhlet extraction with methyl tert-butyl ether (MTBE), and subsequently methanol, followed by a weak anion exchange (WAX) SPE clean-up and injection onto a LC-ESI-MS/MS system, quantification by using isotope dilution. This method was applied for analysis of samples from active (AAS) and passive air samplers (PAS), as well as snow, that were collected in Sweden during the project. Additionally, PUF samples exposed for three months in Örebro in 2017 and several PAS/PUFs spanning two years and sampled as part of the Global Monitoring Plan (GMP), were analysed. The performance of the method was evaluated and gave median recoveries of internal standard of all analytes in blanks of all sample batches ranging from 42 % to 105 %, while median recoveries in real samples were below 20 %. Because of the poor recoveries in samples, only concentrations of ionic PFAS in PAS/PUFs and snow samples from Örebro could be determined. Mean concentrations in PUF samples form Örebro from 2017 were between 30 and 40 pg/m³ and between 6 and 19 pg/m³ for L-PFOS and PFOA, respectively. Lowest concentrations were detected for PFHxS. Concentrations of L-PFOS and PFOA detected in snow in Örebro during the project were roughly one order of magnitude higher compared to the Arctic and about two orders of magnitude lower than in urban China. Overall, more data and a more reliable analytical method is needed to draw conclusions about seasonal or regional variability or correlations between atmospheric PFAS concentrations and wet precipitation. To develop a reliable analytical method for the analysis of PUFs, more real samples need to be available to accurately assess efficiency of clean-ups.

Abstract The solubility of polymers depends on how well the parameters of the polymers and solvents used resemble each other. The more similar the parameters are, the more likely the polymers are to be dissolved. Hansen´s solubility parameters (HSP) tells us how dispersion forces, polar forces and hydrogen bonding influences the structure of the polymers and thereby their solubility. To be able to manufacture effective organic polymer solar cells in the future, we need more knowledge of how polymers and organic solvents interact with each other. This is an essay on how you could gather more knowledge of how primarily the polymer Poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} , (N2200), but also the polymer Poly[2,3-bis-(3-octyloxyphenyl) quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl], (TQ1) dissolves in different organic solvent blends. It is also a test on using the computer software Hansen´s Solubility Parameters in Practice (HSPiP), to estimate the HSP:s for the polymers and the polymer blend. The HSPiP was good at estimating the Hansen solubility parameters for the solubility test on N2200. The software´s drawing tool in the do it yourself- part (DIY) that is used to create a structure code-string (SMILES) for the polymer, did not work as well in this project. The Optimizer in HSPiP made good suggestions of organic solvent blends for N2200 and TQ1, that dissolved the polymers. o-Xylene and tetrahydronaphthalene were the solvents that dissolved N2200 in the solubility test in 24 h and 50 ֯C and among the organic solvent blends it was toluene/1-methylnaphthalene, tetrahydronaphthalene/methyl acetate, tetrahydronaphthalene/o-Xylene and tetrahydronaphthalene/2-methyltetrahydrofuran that were able to dissolve the polymers in the concentrations of 10.0 mg/ml. N2200 dissolved very well up to 10.0 mg/ml in the calculated solvent blends but on the other hand, the samples became very viscous at that concentration and hardly fluent, if fluent at all. It was more difficult to find organic solvent blends that could dissolve N2200 than it was for TQ1. TQ1 dissolved in all solvent ratios that dissolved N2200. / Sammanfattning   Löslighet hos polymerer beror på hur löslighetsparametrarna hos polymeren och det lösningsmedel man använder, liknar varandra. Ju mer löslighetsparametrarna liknar varandra, desto bättre löser sig polymeren i lösningsmedlet. Hansen´s löslighetsparametrar (HSP) talar om hur dispersionskrafter, polära krafter och vätebindningar påverkar strukturer hos polymerer och därigenom deras löslighet. För att kunna tillverka effektiva organiska polymera solceller i framtiden, behöver vi mer kunskap i hur polymerer och organiska lösningsmedel interagerar med varandra. Detta är en uppsats i hur man kan gå tillväga för att ta reda på mer om hur främst polymeren Poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} , (N2200), men också polymeren Poly[2,3-bis-(3-octyloxyphenyl) quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl], (TQ1) löser sig i olika blandningar av organiska lösningsmedel. Det är också ett försök till att använda dataprogrammet, Hansen´s Solubility Parameters in Practice (HSPiP), för att estimera löslighet hos polymererna och polymerblandningen. Det visade sig att HSPiP, var bra på att estimera Hansens löslighetsparametrar för löslighetstestet på N2200. Programmets ritverktyg i DIY (do it yourself/gör det själv), för att skapa SMILES-kod (kod för den ritade molekylens struktur) för polymeren, visade sig vara mindre bra. Optimeraren i HSPiP visade sig kunna föreslå organiska lösningsmedelsblandningar för N2200 och TQ1 som kunde lösa polymererna. o-Xylene och tetrahydronaftalen var de som löste N2200 i löslighetstestet på 24 h med 50 ֯C och av blandningarna var det toluen/1-methylnaftalen, tetrahydronaftalen/metylacetat, tetrahydronaftalen/o-Xylene och tetrahydronaftalene/2-metyltetrahydrofuran som kunde lösa polymererna i koncentrationer av 10.0 mg/ml. N2200 löste sig bra ända upp till 10.0 mg/ml för de beräknade lösningsmedelsblandningarna men däremot blev proverna väldigt viskösa i den koncentrationen och knappt flytande, om alls flytande. Det var svårare att hitta organiska lösningsmedelsblandningar som fungerade för N2200 medan TQ1 kunde lösa sig i allt som fungerade för N2200.

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In this study, the total as well as the water-soluble and bioaccessible fractions of lithium in wheat, durum and barley flour were evaluated together with the isotope ratio. Lithium was determined by inductively coupled plasma – mass spectrometry (ICP-MS). The total lithium content was determined after an open-vessel digestion in HNO3. The water-soluble fraction was evaluated by extraction with deionized water. The bioaccessibility was determined in vitro under simulated stomach digestion conditions. The total lithium content in wheat ranged from 0.91 ng/g to 7.8 ng/g, in durum flour from 1.7 ng/g to 5.2 ng/g and for barley flour from 2.0 ng/g to 6.0 ng/g. For the water-soluble fraction, the ranges were for wheat flour 0.33 ng/g to 4.8 ng/g, for durum flour 0.83 ng/g to 2.5 ng/g and for barley flour 0.81 ng/g to 3.3 ng/g. The bioaccessible lithium content ranges in wheat flour from 0.38 ng/g to 5.3 ng/g, in durum flour from 0.98 ng/g to 1.9 ng/g and in barley flour from 1.3 ng/g to 3.1 ng/g. The water and bioaccessible fractions of the majority of the barley and durum flour samples had an isotope ratio differing statistically significantly from the natural ratio (p<0.05) which indicates enrichment of the heavier isotope. Additionally, speciation of protein bound lithium in water and simulated stomach digestion extracts from respective flours were studied. Extracts from the respective flour types were chromatographically separated and fractionated with an ammonium nitrate buffer on a (size-exclusion-chromatography) SEC-column. Thirty fractions were collected, and their lithium contents were determined by ICP-MS. Lithium was mostly eluted in fraction 14, which indicates that most of the available lithium was protein-bound.

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