| 1. |
- Ericson Jogsten, Ingrid, 1980-
(författare)
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Assessment of human exposure to per- and polyfluorinated compounds (PFCs) : exposure through food, drinking water, house dust and indoor air
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Per- and polyfluorinated compounds (PFCs) are detected in humans worldwide but all sources of human exposure have not been fully characterized. The aim of this thesis was to evaluate the contributions from food, water, air and dust as sources for human PFC exposure in the general population. Per- and polyfluorinated compounds (PFCs) are detected in humans worldwide but all sources of Up to 27 PFCs were determined at trace levels in blood (ng/mL), water (ng/L), foods (ng/g), dust (ng/g) and air (pg/m3) in a selected Catalan population and PFC intake was estimated from the measured PFC concentrations of the different sources of exposure. The major compounds detected in human blood of the studied population were perfluorooctane sulfonate (PFOS; 7.6 ng/mL), perfluorohexane sulfonate (PFHxS; 3.6 ng/mL) and perfluorooctanoic acid (PFOA; 1.8 ng/mL). In general, PFOS was also the major compound detected in most sources of exposure. Food was found to be the dominant pathway for human PFC exposure accounting for more than 70 % of the total intake of both PFOS and PFOA. In the most populated area (the Barcelona Province) where the highest levels were measured, tap water can contribute to the total exposure substantially with more than 50 % for adults. Indoor sources were negligible in the selected area for most PFCs when compared to food and water intake, except for toddlers under a worst case scenario where contribution from dust and food intake were equal (19 %). Pharmacokinetic (PK) modelling resulted in exposure of 103 ng PFOS/day and 33 ng PFOA/day of adults from the internal PFC blood concentrations. This agrees well with the intake estimated from external exposure through food, drinking water, house dust and indoor air of 80 ng PFOS/day and 32 ng PFOA/day and evidently all major exposure sources for the general population were included (in this study).
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| 2. |
- 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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| 3. |
- Kärrman, Anna
(författare)
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Analysis and human levels of persistent perfluorinated chemicals
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- An extensive use of perfluorinated chemicals (PFCs) in the last 50 years has resulted in a worldwide spread of these persistent chemicals. Human populations are subjected to a large number of PFCs in ways that are not yet fully explained. The aims of this thesis are to develop and assure the quality of analytical methods in order to collect information on human levels and to facilitate the assessment of human exposure of PFCs. Solid-phase extraction (SPE) methods for human blood and milk using two sorbents, octadecyl (C18) and a weak anion exchange polymer (WAX), were developed. Perfluorinated alkyl sulfonates (PFSAs) and perfluorinated alkyl carboxylic acids (PFCAs) with carbon chain lengths between four and fourteen together with perfluorooctane sulfonamide (PFOSA) could be extracted from human matrices. These extraction procedures enable selective and sensitive analysis of PFCs in human matrices using single quadrupole mass spectrometry (SQMS). The accuracy and reliability of the methods are discussed in the context of intralaboratory as well as interlaboratory quality assurance. Further improvements of the analysis are discussed including the evaluation of ultra performance liquid chromatography (UPLC). Human whole blood, plasma and serum from Sweden, Australia and the United Kingdom have been analysed. The blood matrix selection in the assessment and comparisons of human exposure to PFCs is crucial. Human plasma contains a high percentage of PFSAs and PFCAs. On the contrary, only about 20% of the total PFOSA content is present in plasma after removal of the red blood cells. Up to eleven persistent PFCs are detected in human blood, with detection levels between 0.1-0.5 ng/mL. A gender difference with higher serum levels for males is apparent. An age trend was observed for perfluorooctane sulfonate (PFOS) levels in serum from Australia. The levels found in Australian serum indicate that emissions from the PFC production facilities are of less importance for human exposure. Matched human milk and serum samples from Sweden show that milk levels of PFCs are about 1% of the maternal serum level. Up to five persistent PFCs are found in human milk from Sweden, with detection limits between 0.005-0.1 ng/mL, and the levels in Swedish pooled milk samples have remained constant between 1996 and 2004. A linear relationship between the maternal serum level and milk level was seen for PFOS and its shorter homologue perfluorohexane sulfonate (PFHxS). The daily intake of PFOS for a nursing infant in Sweden is estimated to be 121 ng/day if the maternal serum level is 20 ng/mL. Lactation is therefore a major exposure source for breast-fed infants. Monomethyl- and dimethyl-branched isomers of PFOS could be separated in human blood using high performance liquid chromatography (HPLC). Human plasma contains a smaller percentage of the linear PFOS compared to commercially available PFOS standard materials, which indicate isomer specific uptake and/or elimination. A difference in the isomer composition is also seen between the countries studied. Human blood from the UK and Australia have significantly lower amount of linear PFOS (59-60%) compared to Swedish blood (68%). This geographical variation suggests different human exposure sources and pathways.
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| 4. |
- Rotander, Anna, 1978-
(författare)
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Monitoring persistent organic pollutants (POPs) in sub-Arctic and Arctic marine mammals, 1984 - 2009
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Arctic has become an important indicator region for assessing persistence and bioaccumulation properties of persistent organic pollutants (POPs). This thesis is aimed at evaluating the occurrence of persistent halogenated POPs in seven species of sub-Arctic and Arctic marine mammals over a 25-year period. The emphasis is on studying temporal variations in concentration of three categories of POPs, including naturally occurring organobromine compounds. Polybrominated diphenyl ethers (PBDEs), Metoxylated diphenyl ethers (MeO-PBDEs), and polychlorinated naphtalenes (PCNs) were extracted from blubber tissue and analyzed by GC/MS. Polyfluoroalkyl substances (PFAS) were extracted from livers and analyzed by LC-MS/MS. Although restricted by the number of pooled samples, survey points, and species available from the specimen banks, the results showed some interesting contamination patterns. Overall, pollutant concentrations showed signs of declining or levelling out, indicating a decrease in POP exposure in the studied areas in recent years. However, increasing levels of long-chain fluorinated compounds (PFCAs) present in most species is a finding of concern, and implies that a continuous monitoring of these compounds is important. Interestingly, a shift over time in the relative abundance of PFOS isomers in ringed seals was observed, indicating a change in exposure to PFOS in recent years. In many of the investigated species the MeO-PBDE levels equalled or exceeded the levels of PBDEs, showing that MeO-PBDEs can be major contributors to the organobromine load in marine mammal species. No apparent relation was found between PBDE and MeO-PBDE levels, adding further support for a natural origin of MeO-PBDEs.
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| 5. |
- Bjurlid, Filip, 1978-
(författare)
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Polybrominated dibenzo-p-dioxins and furans : from source of emission to human exposure
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Brominated flame retardants (BFRs), which are ubiquitous in modern life and the environment, are the major source for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The knowledge about PBDD/Fs is lim-ited compared to other environmental pollutants, even though PBDD/Fs show similar toxicity as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) which are considered to be among the most toxic man-made substances. The aim of the thesis was to provide a better understanding of PBDD/Fs by investigating the occurrence and distribution of PBDD/Fs in the following matrices: soot and gas from an accidental fire site which is a typical source of emission, blubber from marine mammals living in both far remote areas as well as areas close to anthropogenic sources, and finally in human milk from ten nursing mothers.PBDD/Fs was detected in blubber from pilot whales sampled around Faroe Islands, which proved the occurrence in marine mammals in a far remote area. The findings of PBDD/Fs in blubber from Baltic ringed seals showed slightly higher concentrations compared to the pilot whales, which is expected since the Baltic Sea in among the world’s most contam-inated water areas. In the pilot whales and the ringed seals, the average contribution from PBDD/Fs to the total (PCDD/F+PBDD/F) Total Equiv-alent Quantity (TEQ) was low, (1-8%). In gas and soot samples from the accidental fire site, PBDD/Fs were detected in all samples and the contri-bution of PBDD/Fs to the total TEQ was close to 100%. In the human milk samples, PBDD/Fs were detected in all samples and the average con-tribution of PBDD/Fs to the total TEQ was 40%. The results indicate that PBDD/Fs are of concern for human exposure, and should be monitored together with PCDD/Fs in future studies. Moreover, the occurrence at ac-cidental fire sites indicate that PBDD/Fs are a source for occupational ex-posure for firefighters and other professionals. The impact from PBDD/Fs on marine mammalians seems to be of less concern.
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| 6. |
- Chatzidaki, Maria D., 1985-
(författare)
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Formulation and characterization of W/O nano-dispersions for bioactive delivery applications
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main objective of this study was the formulation of food-grade water-in-oil (W/O) nano-dispersions based mainly on medium or long-chain triglycerides. Two types of dispersions were formulated and structurally compared, namely emulsions and microemulsions. The systems were used as matrices for encapsulating targeted bioactive molecules with specific characteristics such as antioxidants or peptides.The structural characterization of the formulated systems was investigated using techniques such as Electron Paramagnetic Resonance (EPR) spectroscopy, Dynamic Light Scattering (DLS), Cryogenic Transmission Electron Microscopy (Cryo-TEM) and Small Angle Xray Scattering (SAXS). The existence of swollen inverse micelles was revealed for the case of microemulsions whereas larger droplets still at the nano-scale were observed for the case of emulsions. Structural differences in the presence of the bioactive molecules or induced by the alteration of components were also observed.In order to study the efficacy of the formulations, the proposed loaded systems were assessed either using EPR spectroscopy or Well Diffusion Assay (WDA) depending on the bioactive molecule. It was found that the encapsulated molecules retained their claimed characteristics when encapsulated to the proposed matrices.Finally, some of the formulated dispersions were investigated for their behavior under gastrointestinal (GI) conditions. A two-step digestion model using recombinant Dog Gastric Lipase (rDGL) and Porcine Pancreatic Lipase (PPL) was proposed to simulate lipid hydrolysis in humans. The studies revealed significant decrease of the rDGL specific activity in the presence of the microemulsion while in the presence of lower percent of surfactants (case of emulsion) no alterations were observed.
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| 7. |
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| 8. |
- Liu, Tao
(författare)
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Chemoinformetics for green chemistry
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on the development of quantitative structure-activity relationship (QSPR) models for physicochemical properties, e.g., vapor pressure and partitioning coefficients. Such models can be used to estimate environmental distribution and transformation of the pollutants or to characterize solvents properties. Here, chemoinformatics was used as an efficient tool for modeling to produce safe chemicals based on green chemistry principles.Experimental determinations are only available for a limited number of the chemicals; however, theoretical molecular descriptors can be used for modeling of all organic compounds. In this thesis, we developed and validated a global and local QSPR model for vapor pressure of liquid and subcooled liquid organic compounds, in which perfluorinated compounds (PFCs) as outliers appeared in the model due to their molecular properties. Subsequently, after the update of the previous model, the vapor pressure of perfluorinated compounds (PFCs) for which no reliable experimental data are available was successfully predicted. At the same time, we used partitioning between n-octanol/water (Kow) and water solubility (Sw) to investigate the similarities and differences between linear solvation energy relationship (LSER) and partial least square projection to latent structures (PLS) models. Further, we developed QSPR model for prediction of melting points and boiling points of PFCs using multiple linear regression (MLR), PLS and associative neural networks (ASNN) approaches, meanwhile, the applicability domain of PFCs was also investigated.Experimental, semi-empirical and theoretical quantitative structure-retention relationship (QSRR) models were used to accurately predict retention factors (logk) in reversed-phase liquid chromatography (RPLC). These models are useful to characterize solvents for determination of the behavior and interactions of molecular structure and develop chromatographic methods. In both of QSPR and QSRR models using the PLS method, the first and second components captured main information which is related to van der Waals forces and polar interactions, and their results coincide with those from LSER.The results showed that the models of physicochemical properties and retention factors (logk) in chromatographic system can be successfully developed by the PLS method. PLS models were able to predict physicochemical properties of organic compounds directly from theoretical descriptors without prior synthesis, measurement or sampling. Further, the PLS method could overcome colinearity in data sets, and it is therefore a rapid, cheap and highly efficient approach
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| 9. |
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| 10. |
- Söderström, Maria, 1960-
(författare)
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Local and global contaminants in Swedish waters : studies on PCBs, DDTs, 4,5,6-trichloroguaiacol and their transformation products in fish and sediments
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is focused on studies on the environmental fate and methodological improvements for determination of the global contaminants, PCBs and DDTs, and locally discharged phenolics, e.g. 4,5,6-trichloroguaiacol (4,5,6-TCG), and their transformation products.4,5,6-TCG is released from bleached pulp mills, and was chosen as a model substance, to study its fate and effects in aquatic environments. In a brackish water model ecosystem, 4,5,6-TCG was shown to be transformed via demethylation, dechlorination, and methylation reactions. Marine periphyton exposed to 4,5,6-TCG was shown to form demethylated, brominated and dimeric metabolites. Several of these metabolites were identified and quantified. Also more tightly bound chlorophenolics were recovered from the substrate, after harsh extraction procedures had been applied. Conjugates of chlorophenols in fish bile were determined as useful tracers for monitoring effluents from bleached pulp mills, even in areas far from the discharge point. To facilitate calculations of water concentrations, bile to water bioconcentration factors (bBCF-values) were determined for several phenolics, including also alkali-labile chlorocatechols.PCBs and DDTs, were assessed in Swedish lakes with background exposure of these global contaminants. A methodological study focus on the contamination risks of airborne PCBs, during freeze-drying and storage of dry sediment samples. Eutrophication has been proposed to cause lower levels of pollutants in biota in lakes due to biomass dilution but in this thesis examples of higher levels of PCBs in sediment traps, sediment and in perch, and also in higher fluxes of PCBs to the sediment, were observed. Phytoplankton are supposed to be responsible for most of the transport of the contaminants. The composition of DDTs in soil, sediment traps and in dated sediment cores was studied in some detail. PCBs, DDTs, HCB and HCHs were measured in sediments from 100 reference lakes included in the National Swedish Environmental Program. The lakes have a large variation in lake characteristics, representative for different areas in Sweden. A gradient was observed for sPCB with decreasing levels from the south west towards the north. The results suggests that longrange transport is the dominating mechanism for distribution of the contaminants analysed. In this study the levles of PCBs and DDTs were lower in eutrophic lakes than in oligotrophic lakes, in an area with similar atmospheric exposure.
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| 11. |
- Geng, Dawei, 1986-
(författare)
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Gas chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry methods for the determination of environmental contaminants
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The recent developments and improvements of instrumental methods for the analyses of the environmental contaminants, especially the persistent organic pollutants (POPs), have made it possible to detect and quantify these at very low concentrations in environmental and biotic matrices.The main objective of this thesis is to demonstrate the capability of the atmospheric pressure chemical ionization technique (APCI), using gas chromatography coupled to tandem mass spectrometry for the determination of a wide range of environmental contaminants, including the POPs regulated by Stockholm Convention, such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), but also the derivates of PBDEs and novel brominated flame retardants (NBFRs).The APCI was operated in charge transfer condition, preferably producing molecular ions. Multiple reaction monitoring (MRM) experiments were optimized by adjusting cone voltage, collision energy and dwell time. Optimization of source parameters, such as gas flows and temperatures was also performed. Low concentration standards were analyzed, achieving a visible chromatographic peak for 2 fg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) demonstrating the excellent sensitivity of the system. Adequate linearity and repeatability were observed for all the studied compounds. The performance of APCI methods was validated against the conventional methods using gas chromatography coupled to high resolution mass spectrometry for chlorinated compounds in a wide range of matrices including environmental, air, human and food matrices.The GC-APCI-MS/MS method was successfully applied to a set of 75 human serum samples to study the circulating levels of POPs in epidemiologic studies. Moreover the method was utilized to establish temporal trends of POPs in osprey eggs samples collected during the past five decades.
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| 12. |
- Jönsson, Sofie, 1976-
(författare)
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Microextraction for usage in environmental monitoring and modelling of nitroaromatic compounds and haloanisoles
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Processes in the environment are often complex and the description and prediction of the behaviour of environmental pollutants requires sophisticated methodology including multidimensional technology. Multivariate statistical methods including principal component analysis (PCA) and partial least squares projection to latent structures (PLS) were used to characterise several nitroaromatic compounds according to a large number of chemical and physical properties. These descriptors were derived from databases and semi-empirical, empirical and quantum-chemical calculations. A model was calculated and used for prediction of experimentally determined relevant environmental parameters, including volatility through gas chromatographic retention times and the distribution between air and water phase using solid-phase microextraction measurements. Analytical microextraction techniques are very well suited for both monitoring and measuring relevant environmental properties. Two such methods, solid-phase microextraction (SPME) and microextraction by packed syringe (MEPS), which are both faster and less resource demanding than traditional methodology, were used to improve the analysis of nitroaromatic compound and haloanisoles. Both techniques showed few interfering compounds and good reproducibility in combination with GC-MS detection. The reproducibility for SPME and MEPS was further enhanced by the usage of isotopically labelled internal standards (nitroaromatic compounds) or internal standards with similar chemical properties as the analytes (haloanisoles). The SPME method for nitroaromatic compounds was tested using industrial wastewater from a wastewater treatment facility receiving input from several nitrogen based industries. Using gas chromatography-negative chemical ionisation-mass spectrometry(GC-NCI-MS) as the final detection, limits of detection (LODs) in the range 0.02–38 ng L−1 were achieved. Results for the 2,4,6-TCA (TCA) and 2,4,6-TBA (TBA) using high resolution GC-MS were even more impressive obtaining LODs in the range 0.02-0.03 ng L-1, which are currently the lowest reported in the international literature. Although the newly developed MEPS technology is generally faster than SPME, similar LODs as for SPME could not yet be achieved. Both methods were found to be so sensitive that TCA and TBA could be detected in wine before it could be sensorically noticed as cork tainted.
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| 13. |
- Karlsson, Marie
(författare)
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Levels of brominated flame retardants in humans and their environment : occupational and home exposure
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Plasma from workers at an electronic dismantling plant were analysed for tri- to heptaBDEs (brominated diphenyl ethers), during 18 months. The different exposed groups showed concentrations ranging from 0.06to 2.8 ng g-1 (l.w.). Only BDE #153 and #183 showed elevated levels compared to the general population in Sweden. The levels in the workers were approximately one order of magnitude higher. No clear trend of increased BDE levels was seen during the study period, nor was there a reduction of the plasma concentration during and after the vacation. Air levels of tri- to decaBDEs, BTBPE (1,2-bis(2,4,6-tribromophenoxy)-ethane) and DeBDethane (1,2-bis(pentabromophenyl)ethane) ranging from 0.082 to 370 ng m-3 were determined at the same electronic dismantling facility. A comparison was made to the levels reported in this facility before an increase of the production volume. The levels of tri- to hexaBDEs, the main compounds in the commercial PentaBDE mixture, were very similar 2001-02 and 2005. Hepta- to decaBDEs, which are the main components in the Octa- and DecaBDE mixtures, were about three to five times higher in 2005 than in 2001-02. The mean level for BTBPE was two times higher 2001-02 while the concentration of DeBDethane measured 73 times higher 2005. Levels of tri- to decaBDEs, BTBPE and DeBDethane were also determined in air, dust and human plasma from households. The levels of the individual BDEs in the plasma samples varied between <0.41 ng g-1 (l.w.) to 17 ng g-1 (l.w). BDE #28 and #47 were present in all air samples, with mean values of 0.015 and 0.12 ng m-3, respectively. BDE #209 was only found in one air sample at a concentration above the detection limit. DeBDethane was detected in only one sample, at a level of 0.023 ng m-3. All the analytes were found in the dust samples at levels ranging from 0.51 to 1600 ng g-1, the highest concentrations were found for BDE #209. DeBDethane was among the most abundant BFRs in the dust at a mean concentration of 47 ng g-1. The concentrations of the sumBDE showed a positive relationship in dust and plasma. Eggs from Northern fulmars (Fulmarus glacialis) in the Faroe Islands were sampled for BFRs to establish the levels in remote regions. . The content of tri- to heptaBDEs, BDE #209 and BTBPE were determined in nine samples in concentrations ranging from non-detectable (< 0.02 ng g−1 l.w.) to 7 ng g−1(l.w.). BTBPE was detected in eight samples at a mean level of 0.11 ng g−1 (l.w). All work included substantial method development and adaption of existing methods. Validation of a solid phase extraction (SPE) method to analyse tri- to heptabrominated diphenyl ethers in human plasma was performed. The SPE extraction method was found to be faster and less solvent- and sample-demanding, compared to the previously used open column extraction based method.
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| 14. |
- Riddell, Nicole, 1979-
(författare)
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Packed Column Supercritical Fluid Chromatography : Applications in Environmental Chemistry
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although gas and liquid chromatography have emerged as dominant separation techniques in environmental analytical chemistry, these methods do not allow for the concurrent analysis of chemically diverse groups of persistent organic pollutants (POPs). There are also a small number of compounds which are not easily amenable to either of these traditional separation techniques. The main objective of this thesis was to address these issues by demonstrating the applicability of packed column supercritical fluid chromatography (pSFC) coupled to mass spectrometry (MS) in various aspects of environmental chemistry.First, pSFC/MS analytical methods were developed for legacy POPs (PCDDs, PCDFs, and PCBs) as well as the emerging environmental contaminant Dechlorane Plus (DP), and issues relating to the ionization of target analytes when pSFC was coupled to MS were explored. Novel APPI and APCI reagents (fluorobenzene and triethylamine) were optimized and real samples (water and soil) were analyzed to demonstrate environmental applicability.The possibility of chiral and preparative scale pSFC separations was then demonstrated through the isolation and characterization of thermally labile hexabromocyclododecane (HBCDD) stereoisomers. The analytical pSFC separation of the α-, β-, and γ-HBCDD enantiomers as well as the δ and ε meso forms was shown to be superior to results obtained using a published LC method.Finally, technical mixtures of phosphorus flame retardants (RBDPP, BPA-BDPP, and DOPO; a group of related compounds which are challenging to analyze concurrently) were examined using multiple analytical techniques and pSFC was found to be the only method which facilitated the accurate determination of the components of all 3 mixtures. This thesis confirms the potential of pSFC/MS as a fast, green, and cost effective means of separating and analyzing environmental contaminants.
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| 15. |
- Salihovic, Samira, 1985-
(författare)
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Development and application of high-throughput methods for analysis of persistent organic pollutants in human blood
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The general public is continuously exposed to a wide range of environmental pollutants. This thesis focuses on a group of anthropogenic chemicals referred to as persistent organic pollutants (POPs) that have been linked to various adverse health effects in humans.The main objective of this thesis was focused on the development and application of high-throughput methods for analysis of a broad range of chlorinated, brominated, and fluorinated POPs in human blood.After establishing that the methods were effective, the two methods were applied to human plasma samples to examine the background levels of a broad range of POPs in human plasma samples among elderly men and women from Sweden and to assess the influence of gender. Levels of a wide range of chlorinated, brominated, and fluorinated compounds were determined in plasma samples collected during 2001-2004 from 1, 016 (50.2% women) 70 year-old participants from the population-based Prospective Study of the Vasculature in Uppsala Seniors (PIVUS). The POPs studied were 16 polychlorinated biphenyls (PCBs), 5 organochlorine pesticides (OCPs), 1 dioxin, 1 brominated flame retardant as well as 14 perfluoroalkyl substances (PFAS) including structural perfluorooctane sulfonic acid (PFOS) isomers. The majority of the studied compounds were detected in the 70-100% of the participants. The structural PFOS isomers were successfully quantified in a sub-sample of 25 men and women. Furthermore, gender differences in the concentrations of the POPs studied showed that the majority of chlorinated and brominated compounds were significantly different when comparing men and women in the study, while the concentrations of the fluorinated compounds were found to be less influenced by gender.This thesis has, by using the developed high-throughput methods requiring only small amounts of human blood, provided background exposure information of a broad range of POPs for an epidemiological study.
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