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Going Beyond the Analysis of Common Contaminants: Target, Suspect, and Non-Target Analysis of Complex Environmental Matrices by High-Resolution Mass SpectrometryHuba, Anna Katarina 14 November 2016 (has links)
The advancements in the field of analytical chemistry, and especially mass spectrometry, have been redefining the field of contaminant detection. While more traditional analysis was sufficient to screen for a small number of well-known compounds, new techniques such as high-resolution mass spectrometry, have enabled a fairly comprehensive screening for previously unknown contaminants. This is enormously beneficial with respect to the analysis of water, air, or soil quality in a society that continuously introduces novel anthropogenic compounds into the environment. This dissertation, thus, focused on the analysis of the uncharacterized portion of compounds in two types of complex environmental matrices (i.e., crude oil and wastewater).
First, targeted and non-targeted analyses were used in order to characterize a crude oil weathering series. Traditional techniques were used for the analysis of well-known oil components and led to the confirmation of biodegradation and photo-degradation trends. An ultrahigh-resolution mass spectrometric analysis was carried out in conjunction with several visualization plots in order to search for unknown compounds. While the study successfully detected a drastic increase in oxygenated components (likely ketones, quinones, and carboxylic acids), it also revealed severe limitations in the state of the art non-targeted crude oil analysis. Some of these limitations were explored in an in-depth atmospheric pressure ionization study of model petroleum compounds, and the dependence of ionization efficiency on numerous factors (e.g., size, heteroatom content, and methylation level) was shown. Since disregarding these intrinsic limitations leads to severely biased conclusions, these results provide crucial information for future crude oil characterization studies. Lastly, suspected and non-targeted analyses were used to evaluate contamination levels in wastewater-impacted interrelated water samples. A significant number of persistent compounds were tentatively identified, which represents an area of environmental concern that needs to be addressed further.
Overall, this dissertation successfully applied non-targeted (in addition to targeted) analysis in order to screen for non-characterized compounds in crude oil and wastewater affected water samples. By doing so, the great potential of the growing field of non-targeted screening in order to expand the range of contaminants to include previously unknown and emerging compounds was highlighted.
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Occurrence of organic micropollutants and hormones in Swedish surface waterForsberg, Malin January 2022 (has links)
The occurrence and source distribution of organic micropollutants (OMPs) have been investigated in Swedish surface waters, in 23 rivers connected to the lakes Vänern, Vättern and Mälaren, 3 Wastewater treatment plants (WWTPs) and 3 Drinking water plants (DWTPs) located in the middle of Sweden was sampled. Compounds such as pharmaceuticals, industrial chemicals, pesticides, personal care products, hormones, Per- and polyflouroalkyl substances (PFASs), isoflavones, stimulants and parabens were selected. The analysis was done by using solid phase extraction (SPE) and Ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Of the 121 studied compounds 91 was detected in concentration levels varying between a few ng/L up to 160 µg/L in wastewater effluent. The detected concentrations of 80 compounds in surface water from rivers varied from low ng L-1up to 3.3 µg/L, 43 OMPs within the range from low ng/L up to 370 ng/ L could be detected in the lakes and 35 OMPs could be found in levels from low ng/L up to 2.9 µg/L in the drinking water. The number of detected compounds and concentration levels clearly decreases from wastewater influent to effluent, rivers, lakes and lastly to drinking water. The concentration levels of OMPs in the surface water samples varied between sampling sites and the three lakes making it clear that Lake Mälaren is the most contaminated one out of these three. OMPs such as antibiotics, antidepressants and personal care products were most frequently detected in all samples. The highest total OMP concentration levels were found in Enköping river (79 µg/L), Lövsta river (33 µg/L), Ösan (16 µg/L) and Lillån (13 µg/L). A risk assessment for drinking water with regard to human health was conducted for two compounds by calculating the Benchmark Quotient (BQ) using drinking water equivalent levels (DWELs). Two compounds, carbamazepine and bezafibrate, was selected based on detection frequency and available toxicity data. While bezafibrate didn’t show any indications of risk to human health, carbamazepine had a BQ of 1.47 which indicates a risk to human health when humans are exposed to these concentration levels over a period of a lifetime. / Genom att använda en målanalys har förekomsten och fördelningen av organiska mikroföroreningar i svenska ytvatten studerats. Vattenprover från 23 vattendrag som antingen mynnar ut i eller börjar i någon av sjöarna Vänern, Vättern eller Mälaren, tre avloppsreningsverk och tre dricksvattenverk i mellersta Sverige har samlats in. Ämnen så som läkemedel, industriella kemikalier, pesticider, hudvårdsprodukter, hormoner, högflorerade ämnen (PFAS), isoflavoner, stimulanter och parabener valdes ut och analyserades med hjälp av fastfasextraktion och vätskekromatografi kopplad till masspektrometer (UPLC-MS/MS).Av de 121 utvalda ämnena kunde 91 av dessa detekteras i koncentrationer som varierade mellan några få ng L-1upp till 160 µg/L i utgående avloppsvatten. I vattendragen kunde 80 av de organiska mikroföroreningarna detekteras i koncentrationer mellan låga ng/L upp till 3.3 µg/L medan endast 43 kunde detekteras i sjöarna inom koncentrationsintervallet låga ng/L till 370 ng/L. Slutligen detekterades 29 mikroföroreningar i dricksvattnet där koncentrationerna varierade mellan några få ng/L upp till 2.9 µg/L. Resultatet visar att antalet detekterade organiska mikroföroreningar och deras respektive koncentrationer tydligt minskar vid jämförelse av de olika matriserna från ingående avloppsvatten till utgående, vattendrag, sjöar och slutligen i dricksvattnet. I ytvattenproverna varierade koncentrationsnivåerna av organiska mikroföroreningar mellan de olika vattendragen och det var tydligt att Mälaren är mer kontaminerad än Vänern och Vättern. Det gick också att se tydliga trender i vilka ämnen som vanligen detekterades i de olika proverna, särskilt bland läkemedlen då ämnen som är antibiotika-klassade eller hör till gruppen antidepressiva var vanligast förekommande. De högsta totala koncentrationerna av organiska mikroföroreningar kunde hittas i Enköpingsån (79 µg/L), Lövstaån (33 µg/L), Ösan (16 µg/L) samt Lillån (13 µg/L). Dessa fyra vattendrag är därmed de mest förorenade i denna studie och kan därför ses som särskilt förorenade. En riskanalys med hänsyn till människors hälsa gjordes på dricksvattnet genom att beräkna en referenskvot (BQ) med hjälp av ekvivalenta dricksvatten-nivåer (DWELs). De två ämnena karbamazepin och bezafibrat valdes på grund av deras detektionsfrekvens (FD) och tillgänglighet av toxicitetsdata. Bezafibrat visade ingen potentiell risk medan karbamazepin hade ett BQ-värde på 1,47 vilket indikerar en potentiell risk till människors hälsa om man utsätts för de funna koncentrationerna under hela sin livstid.
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Human Exposure to Per- and Polyfluoroalkyl : Substances through Fish ConsumptionNauta, Welmoed January 2023 (has links)
Human exposure to per- and poly-fluoroalkyl substances (PFAS) occurs mainly through two pathways, inhalation and ingestion. Dietary exposure to persistent organic pollutants (POPs), including PFAS, is driven mainly by the consumption of foods of marine or terrestrial animal origin. Therefore, the intake of fish from waters in populated or polluted areas may be a source of human exposure to PFAS. The overall aim of the study was to estimate human exposure to PFAS through the consumption of fish caught in Swedish waters. Analyses of extractable organofluorine (EOF) were performed to serve as an important metric alongside target analysis to better understand the total amount of PFAS in the human sera and fish samples. The serum samples represent individuals who have lived at some point about 5 km from the glass industry in Nybro and Emmaboda. For this study with the Glasbruket study population, the highest concentrations were found for PFOS followed by PFOA, PFNA and PFHxS (medians of 7.9, 1.9, 1.4 and 0.8 ng/mL). Also, the difference in this population between men/women and high/low fish consumers were also addressed. It was stated that there was a statistically significant difference in average Σ17 PFAS concentration between the male and female groups (p < 0.05, two-tailed test). However, the differences between the low and high consumer groups were not statistically significant even though the PFAS levels were higher in the high consumer group. The organofluorine mass balance analysis revealed that 80.1% (ranged from 68.3−93.7%) of the EOF in female samples could not be explained, whereas 57.3% (ranged from 0−99.4%) for the male group was of unidentified origin. Two methods were evaluated for PFAS and EOF analysis of fish muscle, namely, acetonitrile extraction and ion-pair extraction. The selected method, the ion-pair extraction, was performed on fish muscle samples. The fish species included perch (Perca fluviatilis), northern pike (Esox Lucius) and zander (Sander lucioperca) that were collected from seven different lakes in the vicinity of Nyro and Emmaboda. The sum of targeted PFAS (∑14PFAS) across all fish samples analysed ranged from 0.9 to 6.2 ng/g. Mostly, perfluoroalkyl carboxylic acids (PFCAs), precursors to PFCAs and novel PFAS were found in the fish samples. A large part of the EOF content cannot be identified with the targeted PFAS compounds. The average identified EOF fraction for all fish was 2.3% (ranging from 0.8 to 7.2%). For this study, 10 PFAS were found in both sera and fish samples. Therefore, freshwater fish consumption can be identified as one of the contributors to the PFAS concentrations in the Glasbruket population. The fish samples contained precursor compounds as well, that were not found in human serum. These precursor compounds can contribute to the concentrations of PFAAs in serum through biotransformation in the human body to perfluoroalkyl acids (PFAAs). Due to the widespread use of PFAS and their persistence in the environment, it is difficult to determine the relationship between the levels found in serum and fish. The Glasbruket population could be exposed to other sources besides fish.
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