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- 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. |
- 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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| 5. |
- Mullin, Lauren Gayle, 1984-
(författare)
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Advances in Mass Spectrometry for the Analysis of Emerging Persistent Organic Pollutants
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mass spectrometry (MS) is a technique widely implemented for the measurement of environmental pollutants. A critical tool for the analysis of persistent organic pollutants (POPs) over several decades, MS as coupled with liquid and gas chromatography (LC and GC) techniques enables the analysis of emerging POPs. The aim of this thesis was to investigate the use of alternative MS-based techniques to assist specific analytical challenges including separation of stereoisomers using supercritical fluid chromatography (SFC), reduced ionization competition with appropriate mobile phase additives, and applied rotationally averaged collision-cross section (CCS) of ions via ion mobility measurements of emerging POPs.Chromatographic efficiency improvements for the brominated flame retardant, hexabromocyclododecane (HBCDD), were implemented through the development of two supercritical fluid chromatography (SFC) methods. Based on the inherent qualities of supercritical fluids, separation of both predominant diastereomers and respective enantiomers was performed in a shorter time with wider chromatographic resolution using SFC than existing LC methods.Turning next to MS ionization considerations, the emerging perfluoroalkyl substance hexafluoropropylene oxide-dimer acid (HFPO-DA) was investigated. Following a survey of analytical methodologies for HFPO-DA, the challenge of extreme dimer formation, in-source fragmentation and very low [M-H]- production was described. Method development using alternative mobile phase additives in currently used LC-MS acquisition techniques was deployed.Finally, ion mobility spectrometry (IMS) was implemented in a non-targeted acquisition study of indoor dust samples. This study used IMS coupled with quadrupole time-of-flight MS to identify a wide range of contaminant classes, including emerging POPs. Identification confidence is a challenge currently facing non-targeted studies, and the use of prediction mechanisms of analyte IMS gas-phase separations was explored.Through applying diverse alternative techniques, increased method performance was explored for emerging POPs analyses.
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