| 1. |
- Koch, Alina, 1990-
(författare)
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Characterisation of PFASs and Organofluorine in Freshwater Environments : Transfer from water to land via emergent aquatic insects
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Per- and polyfluoroalkyl substances (PFASs) are anthropogenic contaminants of emerging concern, because many are highly persistent to degradation and have been linked to adverse effects in humans as well as their ubiquitous spread in aquatic environments. This thesis investigated distribution of PFASs and organofluorine in freshwater environments impacted by PFAS point sources. The main focus was to study potential transfer of PFASs from freshwater systems to riparian zones via emergent aquatic insects as well as potential impacts on riparian invertebrate consumers.Comprehensive sets of samples, such as aquatic insect larvae, emergent aquatic insects, terrestrial invertebrate consumers and water were collected from mainly two sites in Sweden, Ronneby Airport and Kvarntorp industrial area. Homologue and branched isomer profiles, estimates of mass discharges, bioaccumulation factors, stable isotope analysis of carbon and nitrogen as well as organofluorine mass balance and suspect screening analysis were used to characterize the distribution of PFASs in these freshwater environments including their aquatic and terrestrial invertebrate food webs.Results revealed elevated PFAS concentrations in emergent aquatic insects and riparian invertebrate consumers, especially in spiders. Calculated biodriven transfers indicated that impact on riparian insectivores could be substantial on a local and seasonal scale. Furthermore, PFAS concentrations in terrestrial consumers were related to aquatic-based diet and trophic levels, indicating that biomagnification was a major pathway of uptake for some PFASs. Organofluorine mass balance could be closed for most aquatic and for some terrestrial invertebrates from the Ronneby site by target PFAS analysis, whereas a fraction of ~50% in surface water was unidentified organofluorine. Most new PFASs, tentatively identified by suspect screening, were found in water samples and given that contamination occurred decades ago suggested that those PFASs, mainly perfluoroalkyl sulfonamide-based PFASs, are highly water soluble and persistent.
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| 2. |
- Aro, Rudolf, 1992-
(författare)
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Organofluorine Mass Balance and Per- and Polyfluoroalkyl Substance Analysis of Environmental Samples and Human Blood
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Per- and polyfluoroalkyl substances (PFAS) have been linked to a range of negative health and environmental effects. Regulations limiting and/or banning the use of some of the legacy compounds have been introduced. Consequently, the production and use of PFAS has diversified. The risks posed by these newly introduced PFAS to both the environment and humans may be underestimated if they are not evaluated in current monitoring programs. Organofluorine mass balance analysis has been used in previous studies to estimate the overall exposure to PFAS since naturally occurring organofluorine compounds are rare in nature.In this thesis, the organofluorine mass balance analysis was performed on a variety of samples, from surface water to sewage and human blood. The results indicated the ubiquitous presence of unidentified organofluorines in all environmental compartments and human samples, for example, more than 50 % of extractable organofluorine (EOF) in human samples could not be accounted for by an extended list of target analytes. Until these compounds are identified, it is not possible to assess the risks they pose and it could lead to misguided policy decisions.To tackle the increasingly complex analytical picture and ensure more comprehensive screening, a workflow using EOF as an initial metric to identify pollution hot-spots was proposed. The wider adoption of organofluorine mass balance analysis would also require a better understanding of the analytical instrumentation used for this type of work. Experiments carried out here demonstrated the robustness of combustion ion chromatography in EOF analysis and highlighted areas in need of improvement.While organofluorine mass balance analysis has its drawbacks, the potential health and environmental risks posed by the unidentified organofluorine compounds cannot be underestimated.
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| 3. |
- Björnsdotter, Maria, 1989-
(författare)
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Ultra-short-chain perfluoroalkyl acids : Environmental occurrence, sources and distribution
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Ultra-short-chain perfluoroalkyl acids (PFAAs) is a group of highly fluorinated and very stable chemicals. Their small molecular structure in combination with the acidic functional group result in highly polar compounds and concern has been raised as these substances may threaten our drinking water supplies.The aim with this thesis was to study and assess the occurrence, sources, and distribution of ultra-short-chain PFAAs in the environment. The main objectives were to analyze ultra-short-chain PFAAs in surface water with different anthropogenic impact, in atmospheric deposition and surface snow at local and remote locations, and to examine the relevance of local and diffuse input pathways to Lake Vättern, Sweden.The results revealed that ultra-short-chain PFAAs are released to the environment from various sources such as firefighting training sites, landfills, and hazardous waste management facilities. Trifluoroacetic acid (TFA) and perfluoropropanoic acid (PFPrA) were detected in all atmospheric deposition samples and surface snow samples, including those collected at remote sites in the Arctic. Atmospheric oxidation of volatile precursors was found to play a major role in the global distribution of these as well as being the main input pathway to Lake Vättern. A total annual flux of 120–170 kg and 1.3–2.0 kg was observed for TFA and PFPrA, respectively.Trifluoromethane sulfonic acid (TFMS) was detected in most samples and was reported for the first time in atmospheric deposition and surface snow at local as well as remote locations. The discovery of TFMS at remote locations suggests that TFMS is globally distributed. Neither atmospheric degradation of volatile precursors, nor the long-range oceanic transport seem to be main sources of TFMS to the Arctic environment, and local sources seem to be of higher importance for TFMS input to Lake Vättern.
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| 4. |
- Dubocq, Florian, 1994-
(författare)
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Optimizing nontarget workflows for identification of organic contaminants in various matrices
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Since year 2000, production of chemicals around the world has more than doubled. Chemicals are used in many and diverse applications in our everyday life and even if their properties are useful, some can have a negative impact on environment and humans. It is thus important to monitor these chemicals to better understand their impact on the environment and human health.In this thesis, nontarget analysis (NTA) was used to detect and identify organic compounds in various environmental and health relevant matrices such as fish, indoor dust, aqueous film-forming foams (AFFFs) and fire emissions. The aim was to optimize the workflow by extracting relevant chemical information from the analysed matrix and mitigate bias in reported results. Tests were thus performed to optimize sample preparation for fish and dust samples as well as processing data from high-resolution mass spectrometry analysis of dust, AFFFs and fire emissions.Statistical analysis such as analysis of variance (ANOVA) with the help of hierarchical cluster analysis (HCA) enabled the detection of outliers in dust, AFFFs, and gas and soot from fire emissions. Mass defect (MD) plot analysis further enabled the detection of various relevant compounds according to their functional groups and structural properties. The nontarget analysis workflow was supported by target and suspect screening analysis to confirm the efficiency of the optimized overall workflow. Various classes of compounds could be detected and tentatively identified such as flame retardants, liquid crystal monomers or bisphenols in dust samples, organofluorine and fluorine-free surfactants in AFFFs, and flame retardants and hydrocarbons in gas and soot samples .Quality controls were also performed to assess the performance of the optimized workflow.
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| 5. |
- Fredriksson, Felicia, 1993-
(författare)
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Analysis of fluoroalkyl sulfonamide (FASA) based copolymers : An indirect source of non-polymeric PFAS
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Per- and polyfluoroalkyl substances (PFAS) are an extensive group of anthropogenic compounds and are of global concern due to their negative effects on the environment and humans. Most environmental research reports non-polymeric PFAS, leading to a scarce understanding of polymeric PFAS, despite their large share on the global market.In this thesis, two fluoroalkyl sulfonamide (FASA)-based copolymers were studied to gain knowledge regarding their chemical characterization, occurrence, and fate. The main objectives were to provide analytical methods to analyze the FASA-based copolymers in sludge in relation to non-polymeric PFAS and extractable organo-fluorine (EOF) and to study their fate to the arable land when sludge is used as a fertilizer.The results revealed that the FASA-based copolymers were present in all sludge samples and their levels contributed to between 2 and 6 % of the total PFAS. Using two complementary extraction methods, both polymeric and non-polymeric PFAS were captured. However, more than 90% of the EOF belongs to unidentified origin. These results indicate the importance of extending the analysis of polymeric PFAS in environmental research.Further, elevated levels in sludge-amended soil of the C8-FASA-based copolymer were seen, illustrating sludge to be a potential source of C8-FASA-based copolymer to the environment. Both copolymers were transformed into non-polymeric PFAS in earthworms. This thesis provides evidence that these FASA-based copolymers are of concern, both as a direct emission and indirect source of non-polymeric PFAS to the environment.
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| 6. |
- Eriksson, Ulrika, 1972-
(författare)
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Contribution of polyfluoroalkyl phosphate esters (PAPs) and other precursor compounds to perfluoroalkyl carboxylates (PFCAs) in humans and the environment
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Per-and polyfluoroalkyl substances (PFAS) are anthropogenic compounds that have been spread all over the world. The use of fluorotelomer compounds, short-chained homologues, and other PFASs with perfluorinated moieties has emerged recent years. One of these emerging compound classes is polyfluoroalkyl phosphate esters (PAPs), which have the ability to degrade into persistent PFCAs.The aim of this thesis was to assess the contribution of PAPs and other precursors to the exposure of PFCAs to humans and the environment. The main objective was to analyze a wide range of PFAS in human serum, wild bird eggs, indoor dust, waste water, and sludge. There was a significant contribution from selected precursors to the total amount of PFASs in the abiotic compartments indoor dust, waste water, and sludge. Levels of PAPs found in house dust exceeded those of PFCAs and perfluorosulfonic acids (PFSAs), revealing PAPs as a world-wide important exposure source.A net increase was during waste water treatment was observed for several PFASs in Swedish waste water treatment plants. Together with presence of precursor compounds and intermediates in the influent water and the sludge, this suggest that degradation of PFCA precursors contributed to the increase of PFCAs. Detection of precursors in human serum, together with slow declining trends of PFCAs, revealed an ongoing exposure of PFCAs to the general population of Australia. The diPAPs and the FTSAs were also detected in raptor bird eggs from Sweden from both the terrestrial and the freshwater environment. The precursors concentrations and patterns observed reveal that current regulatory measures are insufficient for the purpose of protecting humans and the environment from PFASs exposure.
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| 7. |
- Schönlau, Christine, 1986-
(författare)
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Microplastics in the marine environment and the assessment of potential adverse effects of associated chemicals
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During the last decade plastics have gained interest by scientists as emerging pollutants particularly in the marine environment due to their ubiquity and persistence. While several studies report the occurrence of microplastics in surface waters globally, there are no harmonized methods to sample and measure microplastics, and the knowledge of toxicological effects in the marine ecosystem is scarce. One of the concerns is that microplastics could transfer hazardous chemicals into organism upon ingestion.In this thesis chemical and bioanalytical methods were combined to address the hypothesis that plastic pollution poses a risk for marine ecosystems by exposure to plastic associated chemicals such as sorbed environmental pollutants, additives, and monomers. Six different pristine plastic polymers were studied which have been deployed in the marine and freshwater system for up to 12 months. Potential adverse effects of plastic associated chemicals were investigated with in vitro reporter gene assays which can be activated by several chemical classes. The main focus was on the aryl hydrocarbon receptor-mediated activity for the assessment of dioxin-like chemicals. Different groups of persistent environmental pollutants, which are present in the aquatic environment, were analyzed by gas chromatographic mass spectrometric methods. The contribution of the targeted chemicals to the measured biological activities was examined by conducting potency balance calculations. A better knowledge about the occurrence of microplastics in the waters surrounding Sweden was gained by sampling surface waters comparing two different sampling techniques, trawl and in-situ pump.The plastic pellets induced bioactivities in most tested reporter gene assays and the activities varied by type of polymer. In the majority of samples the contribution of the targeted environmental pollutants to the observed bioactivities was low. Concentrations of microplastics > 0.3 mm in surface waters around Sweden were observed to be low and the findings of this thesis suggest that the tested polymers with sizes 2-4 mm will not lead to an increased risk for marine ecosystems in terms of exposure to chemicals.
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| 8. |
- Stubleski, Jordan, 1990-
(författare)
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Assessing the longitudinal trend of POP concentrations in humans using high-throughput sample preparation methods developed for low-volume samples
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human exposure to anthropogenic persistent organic pollutants (POPs) and their related effects on human health widely vary from person to person, making population-based risk assessment difficult.This thesis aimed to evaluate how individual changes and implemented re-strictions in POP production influenced human exposure. High-throughput sample preparation methods were developed and applied to plasma samples col-lected for an epidemiological study so that the longitudinal change in concen-trations of a broad range of chlorinated (Cl), brominated (Br) and fluorinated POPs in humans could be efficiently evaluated.Two 96-well plate extraction methods were used to determine the concentra-tions of Cl/Br POPs and fluorinated POPs in 150μL of plasma samples collected for the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Plasma samples from 1,016 men and women were collected three times between 2001 and 2014, after participants turned 70, 75 and 80 years old. Dif-ferences in longitudinal trends were observed between Cl/Br POPs and fluori-nated POPs as a result of their differences in time of production and imple-mented restrictions in use. The five year trend in 17 Cl POPs (14 polychlorinated biphenyls and 3 organochlorine pesticides), detected in the majority of the co-hort, and a tetra-brominated diphenyl ether detected in 34% of the follow-up samples showed a significant decrease in plasma concentrations. However, the change in Cl/Br POP concentrations was found to be slower in those who lost more weight and had greater increases in plasma lipids, and showed a faster decline in men versus women. The 8 perfluoroalkyl substances (PFASs) detected in the majority of the cohort showed an overall increase in PFHxS, PFNA, PFDA, and PFUnDA, while PFHpA, PFOA, FOSA, and L-PFOS showed a de-crease over ten years. One of the PFASs that showed an overall increasing trend was heavily influenced by the percentage of PFAS-contaminated drinking water distributed to the residential area.The developed and applied methods showed a high-throughput with precise and consistent results using small sample amounts and the longitudinal trend of POPs in a prospective cohort was efficiently produced. Important information was gained on how residential location, physiological differences and changes, and implemented restrictions in POP production has effected human trends.
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