| 1. |
- Balk, Lennart, et al.
(författare)
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Wild birds of declining European species are dying from a thiamine deficiency syndrome.
- 2009
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 106:29, s. 12001-12006
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Tidskriftsartikel (refereegranskat)abstract
- Wild birds of several species are dying in large numbers from an idiopathic paralytic disease in the Baltic Sea area. Here, we demonstrate strong relationships between this disease, breeding failure, and thiamine (vitamin B(1)) deficiency in eggs, pulli, and full-grown individuals. Thiamine is essential for vertebrates, and its diphosphorylated form functions as a cofactor for several life sustaining enzymes, whereas the triphosphorylated form is necessary for the functioning of neuronal membranes. Paralyzed individuals were remedied by thiamine treatment. Moreover, thiamine deficiency and detrimental effects on thiamine-dependent enzymes were demonstrated in the yolk, liver, and brain. We propose that the mortality and breeding failure are part of a thiamine deficiency syndrome, which may have contributed significantly to declines in many bird populations during the last decades.
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| 2. |
- Bergknut, Magnus, 1973-
(författare)
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Characterization of PAH-contaminated soils focusing on availability, chemical composition and biological effects
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The risks associated with a soil contaminated by polycyclic aromatic hydrocarbons (PAHs) are generally assessed by measuring individual PAHs in the soil and correlating the obtained amounts to known adverse biological effects of the PAHs. The validity of such a risk estimation is dependent on the presence of additional compounds, the availability of the compounds (including the PAHs), and the methods used to correlate the measured chemical data and biological effects. In the work underlying this thesis the availability, chemical composition and biological effects of PAHs in samples of soils from PAH-contaminated environments were examined. It can be concluded from the results presented in the included papers that the PAHs in the studied soils from industrial sites were not generally physically trapped in soil material, indicating that the availability of the PAHs was not restricted in this sense. However, the bioavailable fraction of the PAHs, as assessed by bioassays with the earthworm Eisenia Fetida, could not be assessed by a number of abiotic techniques (including: solid phase micro extraction, SPME; use of semi-permeable membrane devices, SPMDs; leaching with various solvent mixtures, leaching using additives, and sequential leaching) and it seems to be difficult to find a chemical method that can accurately assess the bioavailability of PAHs. Furthermore, it was shown that PAH-polluted samples may be extensively chemically characterized by GC-TOFMS using peak deconvolution, and over 900 components can be resolved in a single run. The chemical characterization also revealed that samples that appeared to be similar in terms of their PAH composition were heterogeneous in terms of their overall composition. Finally, single compounds from this large set of compounds, which correlated with different biological effects, could be identified using the multivariate technique partial least squares projections to latent structures (PLS). This indicates that PLS may provide a valid alternative to Effect Directed Analysis (EDA), an established method for finding single compounds that correlate to the toxicity of environmental samples. Thus, the instrumentation and data evaluation tools used in this thesis are clearly capable of providing a broad chemical characterization as well as linking the obtained chemical data to results from bioassays. However, the link between the chemical analyses and the biological tests could be improved as as an organic solvent that solubilised virtually all of the contaminants was used during the chemical analysis while the biological tests were performed in an aqueous solution with limited solubility for a number of compounds. Consequently the compounds probably have a different impact in the biological tests than their relative abundance in profiles obtained by standard chemical analyses suggests. The availability and bioavailability of contaminants in soil also has to be studied further, and such future studies should focus on the molecular interactions between the contaminants and different compartments of the soil. By doing so, detailed knowledge could be obtained which could be applied to a number of different contaminants and soil types. Such studies would generate the data needed for molecular-based modelling of availability and bioavailability, which would be a big step forward compared to current risk assessment practices.
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| 3. |
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| 4. |
- Cato, Ingemar, et al.
(författare)
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DIOXINS AND OTHER POPS IN THE BALTIC SEA – TRENDS AND CURRENT
- 2009
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Ingår i: 29th International Symposium on Halogenated Persistent Organic Pollutants (Dioxin 2009) in Bejing, China, August 25-30, 2009.
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Konferensbidrag (refereegranskat)abstract
- This paper summarizes a project that was initiated by the Swedish Environmental Protection Agency (EPA) in 2006. It involved several field studies and fate model calculations with the aim to better understand the present contamination situation of dioxins and other persistent organic pollutants (POPs) in the Baltic Sea region. Atmospheric inputs were found to be the dominant external source for all of the selected POPs (dioxins, PCBs and HCB). The model also predicted a significant decline of POP-levels in Baltic surface water if atmospheric concentrations are reduced. This issue is highly prioritized by the Swedish EPA since TEQ-levels of fatty fish exceed maximum residue limits set by the EU. Dioxin source regions were identified by air measurements and analysis of air mass origin. It was found that air that had passed over the European continent contained the highest concentrations, and the congener composition indicated that several major sources types may exist. This research has high relevance for the Swedish EPA, and continued efforts for resolving the dioxin issue of the Baltic Sea will follow.
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| 5. |
- Cornelissen, Gerard, et al.
(författare)
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Freely Dissolved Concentrations and Sediment-Water Activity Ratios of PCDD/Fs and PCBs in the Open Baltic Sea
- 2008
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 42:23, s. 8733-8739
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Tidskriftsartikel (refereegranskat)abstract
- Aqueous concentrations of polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs) as well as polychlorinated biphenyls (PCBs) in the open sea have heretofore been measured by filtering. and extracting large amounts of water. Measurement of freely dissolved concentrations with this technique is difficult because of corrections for sorption to dissolved organic matter. In this study we use a novel, more economic technique using equilibrium passive samplers consisting of 17-mu m thin polyoxymethylene (POM-17), capable of measuring freely dissolved aqueous concentrations (C-W) in pristine (i.e., background) locations. POM-17 was employed in an extensive field campaign at five stations in the open Baltic sea to obtain C-W at two depths (1 m above the seafloor and 25 m below the surface). Median C-W in the overlying water was 2.3 pg toxic equivalents (TEQ)/m(3) PCDD/Fs and 15 pg/L sum 7-PCB, with generally less than a factor two variation among sites and depths. Also freely dissolved concentrations of native compounds in the surface sediment porewater (C-PW) were determined in laboratory batch experiments. The data were used to derive sediment-water activity ratios, which indicate the diffusive flux direction. It was found that the PCDD/Fs and PCBs were in close equilibrium between the sediment porewater and the overlying water. Comparison of C-PW with total sediment concentrations indicated that more than 90% of the compounds were sorbed to sedimentary black carbon.
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| 6. |
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| 7. |
- Cornelissen, Gerard, et al.
(författare)
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Freely dissolved PCDD/F concentrations in the Frierfjord, Norway : comparing equilibrium passive sampling with ""active"" water sampling
- 2010
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Ingår i: Journal of Soils and Sediments. - : Springer Science and Business Media LLC. - 1439-0108 .- 1614-7480. ; 10:2, s. 162-171
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Tidskriftsartikel (refereegranskat)abstract
- Equilibrium passive samplers consisting of 55-A mu m polyoxymethylene (POM) and 170-A mu m polydimethylsiloxane were tested for the analysis of polychlorinated dibenzodioxin/furan (PCDD/F) in the pore water and overlying water of the Frierfjord, a bay in southern Norway. This fjord is heavily polluted with PCDD/Fs due to emissions from a former Mg smelter. Field exposures of both equilibrium passive sampler types yielded similar results for freely dissolved PCDD/F concentrations (C (W,free)) in the overlying water. In addition, the passive sampling data deviated less than an order of magnitude from C (W,free) obtained with conventional ""active"" sampling through pumping/filtration over glass fiber filters and polyurethane foam. A similar comparison was done for the pore water, where POM passive samplers also proved to yield freely dissolved pore water concentrations (C (PW,free)) that deviated less than an order of magnitude from earlier published values measured by direct pore water extraction. The data were also used to derive sediment-water activity ratios, which indicate the diffusive flux direction. High sediment-to-water activity ratios (median value of 160 for 17 congeners) indicated a strong diffusion gradient between the sediment pore water and the overlying water, probably due to deposition of particle-bound PCDD/Fs in combination with low sedimentation rates.
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| 8. |
- Cornelissen, Gerard, et al.
(författare)
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Utvärdering av analysmetoder för fritt lösta organiska ämnen : Fördelning mellan jord/sediment och vatten
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Trots den omfattande användningen av värden på fördelningsförhållanden mellan jord/sediment och vatten varierar KOC-värden för hydrofoba organiska ämnen (HOC) avsevärt. Dessa värden kan i själva verket variera med faktorer upp till 10-100 [1-5]. För HOC förklaras denna variation i KOC -värden huvudsakligen med sotinnehållet i den fasta matrisen [1,4,6]. Denna variation i K-värden har en ofantlig betydelse på hur pass korrekta human- och ekotoxikologiska riskbedömningar man kan göra eftersom SQC sålunda kan felbedömas med en faktor 10-100 [1,4,7-9]. För att komma förbi problemet med den inkorrekta användningen av dessa ovan nämnda allmänna distributionsförhållanden bör koncentrationen av fritt lösta miljögifter i jordar och sediment mätas. På så sätt kan man erhålla platsspecifika distributionsförhållanden mellan jord/sediment och vatten. Dessa erbjuder pålitliga kemiska indikationer på human- och ekotoxikologiska risker [1,7,8,10]. I den föreliggande studien har vi mätt platsspecifika KOC-värden för fältprovsrelevanta PAH, PCB och PCDD/F i jord- och sedimentprover från flera svenska lokaler. Dessa värden jämförs med de allmänna värdena på fördelningsförhållanden vilka används i riskbedömningar och som grundas på totalt jord- eller sedimentinnehåll av HOC. På provtagningslokalerna var skillnaderna mellan de platsspecifika och de allmänna värdena på KOC som följer (tabell 1). Det är viktigt att notera att traditionell riskbedömning, baserad på allmänna KOC -värden, skulle leda till överskattningar av potentiellt biotillgänglig fraktion med dessa faktorer! Resultaten bekräftar att potentiellt biotillgänglig fraktion överskattas vid användandet av allmänna KOC-värden, beroende på en stark sorption av HOC till sot vilket resulterar i minskad biotillgänglighet. Denna överskattning är en faktor 10-30 för PAH, PCB och PCDD/F i svenska jordar och sediment. Det är tillrådligt att mäta koncentrationen av fritt lösta HOC med hjälp av passiva provtagare, istället för mätning av totala HOC-koncentration i jord eller sediment. Analyser med dessa passiva provtagare innebär samma kostnader som konventionella totalextraktioner men ger mycket mer relevant information om potentiellt biotillgänglig fraktion.
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| 9. |
- Engwall, Magnus, 1965-, et al.
(författare)
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Dioxin-like compounds in HPLC-fractionated extracts of marine samples from the east and west coast of Sweden : bioassay- and instrumentally-derived TCDD equivalents
- 1997
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Ingår i: Marine Pollution Bulletin. - 0025-326X .- 1879-3363. ; 34:12, s. 1032-1040
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Tidskriftsartikel (refereegranskat)abstract
- Lipophilic extracts of sediment, settling particulate matter (SPM) and blue mussel (Mytilus edulis) samples, collected at coastal locations on the east and west coast of Sweden, were HPLC-separated into three fractions containing 1. monoaromatic/aliphatic, 2. diaromatic (e,g, polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins and polychlorinated dibenzofuraus (PCDDs/Fs)), and 3, polyaromatic compounds (e,g, polycyclic aromatic hydrocarbons (PAHs)), The fractions were tested for dioxin-like effects using a sensitive bioassay, based on EROD-induction in cultured chicken embryo livers, The concentrations of PCDDs/Fs, PCBs and 15 PAHs in the samples were also determined, The polyaromatic fractions of the sediment samples were more potent as EROD-inducers than the diaromatic fractions, Only a small part of the EROD-induction caused by the polyaromatic fractions could be explained by the analysed PAHs in the samples, indicating presence of non-quantified polyaromatic EROD-inducing compounds in the samples, A greater pollution by EROD-inducing diaromatic and polyaromatic compounds on the east coast site than on the west coast site was seen, The filtration activities and faeces production of the mussels on the east coast experimental site increased the sedimentation of PCDDs/Fs, PCBs and PAHs, The described bioassay proved very useful in the assessment of dioxin-like compounds in both abiotic and biotic samples from the marine environment,
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| 10. |
- Engwall, Magnus, 1965-, et al.
(författare)
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Toxic potencies of extracts of sediment and settling particulate matter collected in the recipient of a bleached pulp mill effluent before and after abandoning chlorine bleaching
- 1997
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 16:6, s. 1187-1194
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Tidskriftsartikel (refereegranskat)abstract
- Extracts of bottom sediment and settling particulate matter (SPM) samples collected in the recipient water body of a bleached pulp mill effluent were separated into three fractions: monoaromatic/aliphatic compounds, diaromatic compounds (e.g., polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans), and polyaromatic compounds assessment of dioxinlike potency were an in vitro assay, based on the induction of 7-ethoxyresorufin-O-deethylase (EROD) in chicken embryo livers, a test for EROD induction in ovo using chicken embryos, and an immunotoxicity test measuring inhibition of lymphoid cell development in cultured fetal mouse thymuses. The samples collected closest to the mill were the most potent. There was a time-dependent decrease in dioxinlike potency in the SPM samples collected near the mill, which coincided with the cessation of chlorine gas bleaching at the mill. The bioassays in general, and the in vitro chicken embryo liver bioassay in particular, proved useful in the assessment of dioxinlike compounds in the sediment and SPM samples. The polyaromatic fractions of the samples were generally more potent than the diaromatic fractions. Only a small part of the effects caused by the polyaromatic fractions could be explained by 15 analyzed PAHs, indicating the presence of unquantified polyaromatic compounds with dioxinlike effects. This investigation indicates that the cessation of chlorine bleaching in the pulp mill resulted in a reduced load of diaromatic dioxinlike compounds in the recipient water body.
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