| 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.
-
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
-
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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| 11. |
- Engwall, Magnus, 1965-, et al.
(författare)
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Toxic potencies of lipophilic extracts from sediments and settling particulate matter (SPM) collected in a PCB-contaminated river system
- 1996
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 15:2, s. 213-222
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Tidskriftsartikel (refereegranskat)abstract
- Sediments and settling particulate matter (SPM) were sampled in a polychlorinated biphenyl (PCB)-contaminated lake, Lake Jarnsjon, and in lakes located up-/and downstream from Lake Jarnsjon. The 7-ethoxyresorufin O-deethylase (EROD)-inducing potencies of lipophilic extracts from sediment and SPM were investigated in organ cultures of chicken embryo livers (denoted in vitro chicken embryo liver bioassay). The extract from sediments collected in Lake Jarnsjon had the greatest EROD-inducing potency of the extracts studied, and it also contained the highest concentrations of PCBs, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins/furans (PCDDs/Fs). The non-ortho-chlorinated PCBs in the extracts were probably major contributors to the EROD induction noted. The EROD-inducing potency of sediment extract from the lake downstream Lake Jarnsjon was higher than that of extract from the upstream lake. This indicates that EROD-inducing substances were transported from Lake Jarnsjon sediment to the lake downstream. The extracts from Lake Jarnsjon sediment and SPM were separated into three fractions containing aliphatic/monoaromatic, diaromatic, and polyaromatic compounds, respectively, which were tested in the in vitro chicken embryo Liver bioassay. In all extracts, the aliphatic/monoaromatic fractions were low in EROD-inducing potency, while the polyaromatic fractions from SPM were more potent than their corresponding diaromatic fractions, indicating that they contained high concentrations of aromatic hydrocarbon (Ah) receptor ligands. Only a small part of the EROD induction caused by the polyaromatic fractions could be attributed to the 15 analyzed PAHs in the samples. The EROD-inducing potencies of the diaromatic fractions correlated quite well with their concentrations of PCDDs/Fs and PCBs. The in vitro chicken embryo liver bioassay detected low concentrations of EROD inducers in the extracts and therefore proved useful for estimating the contents of Ah receptor ligands in environmental samples.
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| 12. |
- Ishaq, R., et al.
(författare)
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PCNs, PCDD/Fs, and Non-orthoPCBs, in Water and Bottom Sediments from the Industrialized Norwegian Grenlandsfjords
- 2009
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:10, s. 3442-3447
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Tidskriftsartikel (refereegranskat)abstract
- Chlorinated toxic planar aromatic compounds were analyzed in the heavily industrialized Grenlandsfjords, which is a system of silled fjords in southern Norway. Surface water samples contained 7.4-160 ng/m(3) polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), 14-410 ng/m(3) polychlorinated naphthalenes (PCNs), and 0.31-2.4 ng/m(3) non-orthochlorinated biphenyls (non-orthoPCBs). The concentrations of PCDD/Fs were about 300 times higher than in the Baltic Sea. Highest level of the compounds was found near a magnesium production plant. Hepta-CDFs and penta-CNs dominated in the inner-fiord waters, and tetra-CB77 was the major non-orthoPCB congener. Sediment samples had PCDD/F concentration of 25-730 ng/g dw. Highest concentration was detected close to the magnesium plant. Octa-CDF dominated in the fjord sediments, especially near the magnesium plant, indicating a discharge-specific contamination with this congener. The isomer composition of PCDD/Fs and of PCNs, was unchanged when comparing samples from different layers of a sediment core from the deep anoxic water. This concludes that essentially zero degradation had occurred during similar to 50 years in this environment
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| 13. |
- Jahnke, Annika, et al.
(författare)
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Possibilities and limitations of equilibrium sampling using polydimethylsiloxane in fish tissue.
- 2009
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 77:6, s. 764-70
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Tidskriftsartikel (refereegranskat)abstract
- Polydimethylsiloxane (PDMS) has been used for passive equilibrium sampling in numerous abiotic environmental matrices. Recently, this approach was extended to lipid-rich tissue. This work investigated the possibilities and limitations of using PDMS thin-film extraction for in tissue equilibrium sampling in fish species of varying lipid content. Polychlorinated biphenyls (PCBs) were used as model lipophilic organic pollutants. PDMS thin-films were inserted in intact fish tissue for differing time periods (1h up to 1 week). The thin-films were then solvent-extracted and the extracts were analyzed using gas chromatography coupled to mass spectrometry. Whether equilibrium had been established was investigated either by using PDMS thin-films of multiple thicknesses (140-620 microm) or by assessing kinetics by means of time series. Equilibration was found to be rapid (i.e. in the range of hours) in lipid-rich fish whereas equilibrium was not achieved within one week in tissues with low or medium lipid content (i.e. up to 2% lipids). Regarding lipid-rich fish, the newly developed method was found to be sufficiently sensitive to determine equilibrium partitioning concentrations of PCBs in lipids of samples from the Baltic Sea, and it is a promising approach for any kind of fatty tissue.
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| 14. |
- Lundgren, Kjell, et al.
(författare)
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Flux estimates and sedimentation of polychlorinated naphthalenes in the northern part of the Baltic sea
- 2003
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Ingår i: Environmental Pollution. - 0269-7491 .- 1873-6424. ; 126:1, s. 93-105
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Tidskriftsartikel (refereegranskat)abstract
- The concentrations and fluxes of polychlorinated naphthalenes (PCNs) were measured in surface sediments, and settling particulate matter collected in sediment traps, at two coastal and two offshore sampling stations in the Gulf of Bothnia, northern Baltic Sea, Sweden. The PCN concentrations (of tetra- to hepta-chloro congeners) in the surface sediments ranged from 0.27 to 2.8 ng/g dry weight and were of the same order of magnitude as background concentrations reported previously in Europe. The PCN fluxes in the southern basin (0.93 and 0.86 μg/m2/year) of the Gulf of Bothnia were higher than those in the northern basin (0.58 and 0.49 μg/m2/year); they were also higher near the coast than in the open sea. These PCN fluxes are similar to the pre-industrial levels determined from lake sediments in northwest England. The PCN homologue distribution changed from a relatively even distribution in samples collected near the coast, to TeCNs dominating in the samples from the open sea. This indicates that higher chlorinated PCNs are deposited and retained in sediments to a higher degree near the coast. The total annual deposition of PCNs in sediments in the Gulf of Bothnia was estimated to be 91 kg/year. Background concentrations in sediments, fluxes and annual sedimentation rates of polychlorinated naphthalenes were measured and estimated at two coastal and two offshore remote sampling stations in the Gulf of Bothnia, northern Baltic Sea.
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| 15. |
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| 16. |
- Lundgren, Kjell, et al.
(författare)
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Polychlorinated Naphthalene Levels, Distribution, and Biomagnification in a Benthic Food Chain in the Baltic Sea
- 2002
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Ingår i: Environmental Science & Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 36:23, s. 5005-13
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Tidskriftsartikel (refereegranskat)abstract
- The scientific literature contains little information regarding bioaccumulation and biomagnification of polychlorinated naphthalenes (PCNs) in food webs. Here we present new information on the food chain transfer of PCNs within a food chain in a subarctic environment. PCNs (tetra- to hepta-chloro congeners) were measured in surface sediments and in a marine benthic food chain, comprising amphipods, isopods, and fourhorned sculpins. Samples were collected from five locations in the Gulf of Bothnia, northern Baltic Sea. PCN concentrations in the sediments were similar to background levels determined previously in sediments from the northern hemisphere. Measurement of the carbon content of the sediments allowed the calculation of biota to sediment accumulation factors (BSAFs). Tetra- and penta-CNs exhibited BSAF values greater than one, while BSAFs for the more chlorinated PCNs were less than one. This suggests more efficient assimilation, by amphipods, of the less chlorinated PCNs. A decrease in PCN concentrations from the lowest to the highest trophic level was demonstrated (amphipods: 10-69 ng/g lw; isopods: 3.9-16 ng/g lw; fourhorned sculpins: 0.54-1.5 ng/g lw). Biomagnification factors (BMFs) were calculated based on the concentrations of the congeners. These indicated that a few congeners biomagnified significantly: the highest BMFs (0.09-1.4) were found for 2,3,6,7-substituted congeners and those lacking adjacent hydrogen-substituted carbon atoms.
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| 17. |
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| 18. |
- Magnér, Jörgen A, et al.
(författare)
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Evaluation of poly(ethylene-co-vinyl acetate-co-carbon monoxide) and polydimethylsiloxane for equilibrium sampling of polar organic contaminants in water.
- 2009
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 28:9, s. 1874-80
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to develop a passive absorptive equilibrium sampler that would enable the determination of the concentrations of polar organic compound (POC) in water more efficiently than existing techniques. To this end, a novel plastic material, poly(ethylene-co-vinyl acetate-co-carbon monoxide) (PEVAC), was evaluated and the results were compared with an existing silicone-based passive absorptive equilibrium device. Seven compounds (imidacloprid, carbendazim, metoprolol, atrazin, carbamazepine, diazinon, and chlorpyrifos), a mixture of pharmaceuticals, and pesticides with a logarithmic octanol-water partition coefficient ranging from 0.2 to 4.77 were selected as model substances for the experiments. The results showed that six of the seven selected POCs reached distribution equilibrium within 4 d in the two materials tested. A linear relation with a regression coefficient of more than 0.8906 between the established logarithmic absorbent-water partition coefficient and the calculated logarithmic dissociation partition coefficient of the selected compounds in the two polymers was observed. The correlation between these two coefficients was within one order of magnitude for the compounds that reached equilibrium in the two polymers, which demonstrates that both materials are suitable for mimicking biological uptake of POCs. The PEVAC material showed an enhanced sorption for all selected compounds compared to the silicone material and up to five times higher enrichment for the most polar compound. Fluorescence analysis of the sampler cross-section, following the uptake of fluoranthene, and proof that the sorption was independent of surface area variations demonstrated that the PEVAC polymer possessed absorptive rather than adsorptive enrichment of organic compounds.
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| 19. |
- Magnér, Jörgen, 1971-, et al.
(författare)
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Bag-SPE – A convenient extraction method for screening of pharmaceutical-residues in influent and effluent water from sewage treatment plants
- 2009
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer. - 1618-2642 .- 1618-2650. ; 395:5, s. 1481-1489
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Tidskriftsartikel (refereegranskat)abstract
- Bag-SPE is a solid phase extraction (SPE) technique here applied to sample pharmaceutical residues in wastewater. The device consisting of 20 mg polystyrene-divinylbenzene (PS-DVB) enclosed in a woven polyester-fabric was immersed into 20 mL sample. Extraction of the analytes was performed under gentle rotation (25 rpm) until distribution equilibrium was achieved (4 hours). The extraction efficiency for thirteen pharmaceuticals was evaluated for the bag-SPE sampler compared to a conventional SPE cartridge (Oasis HLB). All analyzes were determined on an ultra performance liquid chromatography (UPLC) coupled to a quadrupole time of flight (QToF) mass spectrometer. The detection limit of the bag-SPE technique for the analytes in wastewater ranged from 15-100 ng/L with recoveries between 20.7-58.2 % and ion-suppressions between 2.2-53.2 %. Although the extraction efficiencies were lower with the bag-SPE sampler compared to the SPE technique, the two methods showed similar detection limits due to the lower ion-suppression experienced with the bag-SPE. The results demonstrate that bag-SPE is an attractive alternative to the more, in terms of manual handling, demanding SPE-technique.
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| 20. |
- Magnér, Jörgen, 1971-
(författare)
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Methodologies to assess the fate of polar organic compounds in aquatic environments
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polar organic compounds (POCs) are chemicals with polar functional groups in their structure. The functional groups make the compounds hydrophilic and less prone to partition with biota. However, the knowledge of their fate is limited due to difficulties associated with their measurements. Although, the persistence of POCs in the environment is generally low, they are considered to be semi-persistent compounds due to their continuous introduction to the environment via wastewater. Studies have shown that complex mixtures of POCs of different classes may have synergistic toxic effects on biota at environmental concentration levels. Therefore, it is important to develop analytical methods in order to establish the occurrence and fate of POCs in aquatic environments. In Study I, a positive correlation between the sorption of a novel poly(ethylene-co-vinyl acetate-co-carbon monoxide) (PEVAC) material and the theoretical logarithmic dissociation partition coefficient (Log D) for seven POCs was observed. The PEVAC material showed an enhanced sorption of the POCs compared to the silicone material. Study II, demonstrated that the PEVAC sampler assess the freely dissolved concentration of POCs in aquatic environments. The results showed that the PEVAC polymer is an attractive alternative to silicone for mimicing the biological uptake of POCs in aquatic environments. Additionally, Study II showed that total extraction is appropriate for determination of the freely dissolved concentration of uncharged POCs with Log KOW < 2.67 in natural water. In study III, a novel bag-solid phase extraction (bag-SPE) technique was compared to a conventional SPE-technique. Despite that the extraction efficiencies for POCs in wastewater were lower using the bag-SPE method, the two methods showed similar detection limits due to the lower ion-suppression experienced with the bag-SPE. In study IV the bag-SPE method was further developed with the aim of lowering the detection limits for POCs. Detection limits (LOD) below 13 ng/L showed that the bag-SPE method was suitable for determination of POCs in surface sea water.
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| 21. |
- Magnér, Jörgen, 1971-, et al.
(författare)
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The Ability of a Novel Sorptive Polymer to Determine the Freely Dissolved Fraction of Polar Organic Compounds in the Presence of Fulvic Acid or Sediment
- 2009
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer. - 1618-2642 .- 1618-2650. ; 395:5, s. 1525-1532
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, a novel plastic material, poly(ethylene-co-vinyl acetate-co-carbon monoxide) (PEVAC), was evaluated as an absorptive passive equilibrium sampler for determination of the freely dissolved fraction of seven polar organic contaminants (POCs) in the presence of fulvic acid (FA) and sediment. The seven compounds selected were imidacloprid, carbendazim, metoprolol, atrazin, carbamazepine, diazinon and chlorpyrifos, i.e. a mixture of pharmaceuticals and pesticides having logarithmic octanol/water partitioning coefficient (Log KOW) ranging from 0.2 to 4.77. The experiments demonstrated that the PEVAC sampler is well suited for determination of the freely dissolved fraction of chemicals in aquatic environments. Generally, the freely dissolved fraction of the POCs decreased with increasing hydrophobicity. However, strong interactions with functional groups of the organic matter seemed to dominate the partitioning for imidacloprid and carbendazim, having logarithmic dissociation partition coefficient (Log D) < 1.47, and for metoprolol which is positively charged at neutral pH.
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| 22. |
- Nfon, Erick, et al.
(författare)
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Biomagnification of organic pollutants in benthic and pelagic marine food chains from the Baltic Sea
- 2008
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 397:1-3, s. 190-204
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Tidskriftsartikel (refereegranskat)abstract
- The trophic transfer of organic pollutants with varying physical chemical properties was determined in both a pelagic and benthic food chain using delta N-15 as a continuous variable for assessing trophic levels. The trophic transfer of organic pollutants through the entire food chain in terms of food chain magnification factors (FCMFs) was quantified from the slope of the regression between In [concentration] and delta N-15. Organic pollutants with statistically significant FCMFs >1 were considered to biomagnify within the food chain, whereas those with FCMFs < 1 were considered to trophically dilute. Statistically significant FCMFs >1 were found for PCB congeners and organochlorine pesticides in the Baltic food chains whereas statistically significant FCMFs <1 were found for PAHs and PCNs due to trophic dilution resulting from metabolism. FCMFs were generally greater in the pelagic food chain than in the benthic food chain. However, estimated FCMFs for the benthic food chain are likely in error, as the delta N-15 method suggested a food chain structure which was not consistent with the known dietary patterns of the species. Biomagnification factors (BMFs) were additionally calculated as the ratio of the lipid normalized concentrations in the predator and prey species with adjustment for trophic level and were generally consistent with the FCMFs with BMF >1 for PCBs and organochlorines.
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| 23. |
- Nfon, Erick, et al.
(författare)
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Trophodynamics of mercury and other trace elements in a pelagic food chain from the Baltic Sea
- 2009
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 407:24, s. 6267-74
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Tidskriftsartikel (refereegranskat)abstract
- Mercury (Hg) and 13 other trace elements (Al, Ti, V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were measured in phytoplankton, zooplankton, mysis and herring in order to examine the trophodynamics in a well-studied pelagic food chain in the Baltic Sea. The fractionation of nitrogen isotopes (delta(15)N) was used to evaluate food web structure and to estimate the extent of trophic biomagnification of the various trace elements. Trophic magnification factors (TMFs) for each trace element were determined from the slope of the regression between trace element concentrations and delta(15)N. Calculated TMFs showed fundamental differences in the trophodynamics of the trace elements in the pelagic food chain studied. Concentrations of Al, Fe, Ni, Zn, Pb and Cd showed statistically significant decreases (TMF<1) with increasing trophic levels and thus these trace elements tropically dilute or biodilute in this Baltic food chain. Cu, As, Cr, Mn, V, Ti and Co showed no significant relationships with trophic levels. Hg was unique among the trace elements studied in demonstrating a statistically significant increase (TMF>1) in concentration with trophic level i.e. Hg biomagnifies in this Baltic food chain. The estimated TMF for Hg in this food chain was comparable to TMFs observed elsewhere for diverse food chains and locations.
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| 24. |
- Noaksson, Erik, et al.
(författare)
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Gonad development and plasma steroid profiles by HRGC/HRMS during one reproductive cycle in reference and leachate-exposed female perch (Perca fluviatilis)
- 2004
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Ingår i: Toxicology and Applied Pharmacology. - : Elsevier BV. - 0041-008X .- 1096-0333. ; 195:2, s. 247-261
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Tidskriftsartikel (refereegranskat)abstract
- Endocrine processes were studied in reference female perch (Perca fluviatilis) from Lake Djursjön and in leachate-exposed females from Lake Molnbyggen during one reproductive cycle. A high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) technique enabled the analysis of circulating sex steroids [progesterone (P), 17α-hydroxyprogesterone (17α-OHP), androstenedione (A), testosterone (T), estrone (E1), and 17β-estradiol (E2)], the maturation-inducing hormone (MIH) 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-P), and glucocorticoids [11-deoxycortisol (11-DC) and cortisol]. Body and organ measurements, ratio of sexually mature (SM) females, and frequencies of body lesions, were also recorded. High frequencies of body lesions and a low ratio of SM females were generally found in Molnbyggen. These females also had lower gonadosomatic index (GSI) and liver-somatic index (LSI) in the early stages of vitellogenesis, indicating either a delayed onset of oogenesis or an impaired vitellogenesis. Non-reproducing females from both lakes showed a similar LSI cycle as SM females. Increasing T and A levels in SM females from Djursjön coincided with the GSI peak at the time of spawning. These two androgens were on several occasions lower in SM females from Molnbyggen, possibly the result of a disrupted 17,20-lyase activity of the P450 17α enzyme because only minor effects were observed on circulating P and 17α-OHP levels. E2 and E1 levels increased during vitellogenesis in females from both lakes, with E1 levels more closely resembling the peaks of A and GSI. Peak levels of 17α,20β-P at the time of spawning confirmed its function as the MIH in perch, while the simultaneous peak of 11-DC suggests that it also may be involved in final maturation of the oocytes.
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| 25. |
- Norling, Kristoffer, et al.
(författare)
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Secure Distributed Co-Simulation over Wide Area Networks
- 2007
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Konferensbidrag (refereegranskat)abstract
- Modeling and simulation often require different tools for specialized purposes, which increase the motivation to use co-simulation. Since physical models often are describing enterprises¿ primary know-how, there is a need for a sound approach to securely perform modeling and simulation. This paper discusses different possibilities from a security perspective, with focus on secure distributed co-simulation over wide area networks (WANs), using transmission line modeling (TLM). An approach is outlined and performance is evaluated both in a simulated WAN environment, and for a real encrypted co-simulation between Sweden and Australia. It is concluded that several parameters affect the total simulation time, where especially the network delay (latency) has a significant impact.
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| 26. |
- Persson, Johan N, et al.
(författare)
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Soot-Carbon Influenced Distribution of PCDD/F in the Marine Environment of the Grenlandsfjords, Norway
- 2002
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Ingår i: Environmental Science and Technology. - 0013-936X .- 1520-5851. ; 36:23, s. 4968-4974
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Tidskriftsartikel (refereegranskat)abstract
- The particle associations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were studied in both the water column and the surface sediments of a marine fjord system and were found to poorly obey expectations from the organic matter partitioning (OMP) paradigm. The field observations were instead consistent with the presence of a stronger sorbent subdomain such as pyrogenic soot-carbon (SC) playing an important role in affecting the environmental distribution and fate of PCDD/Fs. Solid-water distribution coefficients (Kd) of PCDD/Fs actually observed in the water column were several orders of magnitude above predictions from a commonly used OMP model. Even when these elevated Kd values were normalized to the particulate organic carbon (POC) content (i.e., KOC), the variability in KOC for individual PCDD/Fs at different fjord locations and seasons of factors 100-1000 suggested that bulk organic matter was not the governing sorbent domain of the suspended particles. Further, POC-normalized particle concentrations of PCDD/Fs (COC) in a vertical profile (surface water-bottom water-surface sediment) revealed a strong increasing trend with depth. Factors of about 100 higher COC for all PCDD/Fs in the sediment than in the surface water could not be explained by higher fugacity in the surrounding deep water nor with C:N or δ13C indexes of selective aging of the bulk organic matter. Instead this was hypothesized to reflect selective preservation of a more recalcitrant and highly sorbing, but minor, subdomain such as soot. The extent of enhanced PCDD/F sorption, above the OMP predictions, was positively correlated with the SC:POC ratio of the suspended particles in surface and deep waters. Finally, the geographical distribution of sedimentary PCDD/F concentrations were better explained by the SC content than by the bulk OC content of the sediment. Altogether, these field-based findings add to recent laboratory-based sorption studies to suggest that we need to consider both amorphous OC partitioning domains and SC particles as carriers of planar aromatic contaminants if we are to explain the environmental distribution and fate of pollutants such as PCDD/Fs. (54 refs.
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| 27. |
- Persson, N. Johan, 1969-
(författare)
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Models of the Distribution of Persistent Organic Pollutants in the Marine Environment
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Persistent organic pollutants (POPs) is a group of chemicals that are toxic, undergo long-range transport and accumulate in biota. Due to their persistency the distribution and recirculation in the environment often continues for a long period of time. Thereby they appear virtually everywhere within the biosphere, and poses a toxic stress to living organisms. In this thesis, attempts are made to contribute to the understanding of factors that influence the distribution of POPs with focus on processes in the marine environment. The bioavailability and the spatial distribution are central topics for the environmental risk management of POPs. In order to study these topics, various field studies were undertaken. To determine the bioavailable fraction of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated naphthalenes (PCNs), and polychlorinated biphenyls (PCBs) the aqueous dissolved phase were sampled and analysed. In the same samples, we also measured how much of these POPs were associated with suspended particles. Different models, which predicted the phase distribution of these POPs, were then evaluated. It was found that important water characteristics, which influenced the solid-water phase distribution of POPs, were particulate organic matter (POM), particulate soot (PSC), and dissolved organic matter (DOM). The bioavailable dissolved POP-phase in the water was lower when these sorbing phases were present. Furthermore, sediments were sampled and the spatial distribution of the POPs was examined. The results showed that the concentration of PCDD/Fs, and PCNs were better described using PSC- than using POM-content of the sediment. In parallel with these field studies, we synthesized knowledge of the processes affecting the distribution of POPs in a multimedia mass balance model. This model predicted concentrations of PCDD/Fs throughout our study area, the Grenlandsfjords in Norway, within factors of ten. This makes the model capable to validate the effect of suitable remedial actions in order to decrease the exposure of these POPs to biota in the Grenlandsfjords which was the aim of the project. Also, to evaluate the influence of eutrophication on the marine occurrence PCB data from the US Musselwatch and Benthic Surveillance Programs are examined in this thesis. The dry weight based concentrations of PCB in bivalves were found to correlate positively to the organic matter content of nearby sediments, and organic matter based concentrations of PCB in sediments were negatively correlated to the organic matter content of the sediment.
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| 28. |
- Reth, Margot, et al.
(författare)
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Water-to-air transfer of perfluorinated carboxylates and sulfonates in a sea spray simulator
- 2011
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Ingår i: Environmental Chemistry. - 1448-2517 .- 1449-8979. ; 8:4, s. 381-388
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Tidskriftsartikel (refereegranskat)abstract
- One hypothesis for the origin of perfluorinated alkyl acids, their salts and conjugate bases (here collectively termed PFAAs) in the atmosphere is transfer from the surface ocean by sea spray, the mechanistic explanation being that the surface active properties of PFAAs result in their enrichment on the surface of bursting bubbles. The water-to-air transfer of C(6)-C(14) perfluorocarboxylates (PFCAs) and C(6), C(8) and C(10) perfluorosulfonates (PFSAs) was studied in a laboratory scale sea spray simulator containing tap water spiked with PFCAs and PFSAs. The sequestration of the PFAAs out of bulk water and to the air-water surface was shown to increase exponentially with the length of the perfluorinated alkyl chain. Volatilisation of the PFAAs from an aqueous solution in the absence of spray resulted in less than 1% transfer to the atmosphere during the experiment. In the presence of spray the transfer rate from water to air increased by up to 1360 times. The enhancement was dependent on the PFAA chain length, with the C(6) carboxylate showing an enhancement of a factor of 37, the C(7) carboxylate an enhancement of 320, whereas for all remaining PFAAs the enhancement exceeded 450 with the exception of the C(14) carboxylate (106).
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| 29. |
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| 30. |
- Sundberg, Henrik, et al.
(författare)
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Contribution of commonly analyzed polycyclic aromatic hydrocarbons (PAHs) in sediment to potential toxicity in early life-stages of rainbow trout (Oncorhynchus mykiss)
- 2006
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - : NRC Research Press. - 0706-652X .- 1205-7533. ; 63:6, s. 1320-1333
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Tidskriftsartikel (refereegranskat)abstract
- In a series of bio-effect-directed fractionation experiments, we investigated the potential toxicity of sediment extracts from a contaminated bay. A previous study investigated abnormalities and hepatic ethoxyresorufin O-deethylase (EROD) activities in rainbow trout (Oncorhynchus mykiss) larvae by exposing newly fertilized eggs to the total extract and to fractions separated by degree of aromaticity. A major part of the potential toxicity was isolated in a fraction containing polycyclic aromatic compounds (PACs). In this study, we prepared a synthetic PAC mixture with 17 commonly analyzed polycyclic aromatic hydrocarbons (PAHs) in amounts equimolar to those found in the sediment PAC fraction. The 17 PAHs, which included 11 of the 16 United States Environmental Protection Agency (US EPA) priority PAHs, were unable to account for the toxicopathic effects observed and could explain less than 4% of the total EROD induction. The lack of a clear relationship between toxicopathic effects and EROD induction underlines the need for a battery of biomarkers for estimating environmental risk. These results reveal the limits of our knowledge regarding compounds responsible for potential toxicity in field situations.
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| 31. |
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| 32. |
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| 33. |
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| 34. |
- Sundberg, Henrik, 1973-
(författare)
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Toxicological and Chemical Characterization of Organic Pollutants with Potential to Adversely Affect Fish
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Several investigations have described adverse effects in fish inhabiting polluted areas, though the causative, or aetiologic compounds have not been substantiated. Since environmental pollutants exist as complex mixtures, reliable risk estimations are difficult to obtain. Chemical analyses of known toxicants are not sufficient since unknown toxic compounds will not be identified. Diagnostic tools – biomarkers – will provide information on the potential toxicity, but only limited information on the aetiologic compounds. A promising strategy for pinpointing the major toxicants in environmental samples is to fractionate samples in several steps, guided by the toxicity of the isolated fractions. This enables a more precise identification of aetiologic compounds than the analysis of a non-fractionated sample.The present thesis describes the toxicological and chemical characterization of organic pollutants in the polychlorinated biphenyl (PCB) polluted bay Örserumsviken on Sweden’s Baltic coast. Compounds in organic extracts of abiotic matrices collected in the bay were separated by degree of aromaticity prior to exposing early life-stages of rainbow trout (Oncorhynchus mykiss). The fraction containing PCBs and other dicyclic aromatic compounds (DACs) was less potentially toxic than the fraction containing polycyclic aromatic compounds (PACs). An estimated 1-5% of the total ethoxyresorufin O-deethylase (EROD) induction could be explained by PCBs, and less than 4% by the most commonly monitored PACs. Though the aetiologic compounds were not identified, a significant part of the EROD induction was isolated in a PAC-subfraction containing compounds with more than five rings and the major part of teratogenicity was isolated in a fraction containing three- and four-ringed PACs. As markers for the unidentified potent compounds in the DAC- and PAC-fractions, PCBs and polycyclic aromatic hydrocarbons (PAHs) were analyzed in feral fish eggs from the bay. Adult northern pike (Esox lucius) had elevated levels of hepatic DNA adducts, which correlated with PAH concentrations in their eggs. ΣPCB concentration in pike eggs was equal to the injected concentration in the highest dose of the DAC-fraction, which caused a 50-fold EROD induction in rainbow trout larvae. This demonstrates that the compounds present in the abiotic matrices posed a threat to all life-stages of fish in this area.The findings in this thesis clearly reveal the limits of our knowledge regarding compounds responsible for potential toxicity in field situations. We need to place greater emphasis on the toxicological and chemical implications of our continuous release of PACs and to work for much more restrictive regulations.
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| 35. |
- Widell, Bodil, 1972-
(författare)
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Development of GC-HRMS procedures for determination of naturally occuring polar compounds in various environmental applications
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall objectives of this dissertation were to gain further understanding of the two following environmentally significant issues: (i) Determination of natural steroid hormones in blood plasma from perch (Perca fluviatilis) during a reproductive cycle and to evaluate the possibility of using the steroid composition as a biomarker for early signs of endocrine disruptive effects. (ii) Determination of dissolved free amino acids in size resolved airborne particles collected over the Arctic pack ice area (>80°N) in summer and to study their overall relationship with the ocean surface microlayer as a potential source. This was made possible by the development of two separate gas chromatographic–high resolution mass spectrometry methods. To enable separation with gas chromatography both steroids and amino acids had to be chemically modified to increase their volatility. The small sample volumes available and low concentrations of analytes required a multi-step clean-up procedure to enable determination. The results showed that the circulating levels of steroids in perch varied over the year and that the levels of some androgens were lower in female perch exposed to leachate from a refuse dump compare to unexposed perch, which may explain the decline in fertility observed for the former group. This also indicated that the steroid composition in the blood plasma may function as a sensitive biomarker. The levels of dissolved free amino acids were enriched in the submicrometer aerosol, peaking in sizes around 100nm aerodynamic diameter. These findings do support a previous assumption that the most likely source for these particles is the surface microlayer of the open water between the ice floes. The most likely exchange mechanism of biogenic matter between ocean and atmosphere is the bursting of bubbles at the surface of the leads. This mechanism would provide a very important and poorly understood link between cloud radiative properties and marine biochemistry in the summer high Arctic (>80°N) through the production of cloud condensation nuclei.
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