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1.
  • Balk, Lennart, et al. (author)
  • Wild birds of declining European species are dying from a thiamine deficiency syndrome.
  • 2009
  • In: 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
  • Journal article (peer-reviewed)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.
  • Brunström, Björn, et al. (author)
  • EROD induction in cultured chick embryo liver : a sensitive bioassay for dioxin-like environmental pollutants
  • 1995
  • In: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 14:5, s. 837-842
  • Journal article (peer-reviewed)abstract
    • A technique for studying 7-ethoxyresorufin O-deethylase (EROD) induction in chick embryo liver in vitro was developed. Livers from 8-d-old embryos were cultured in rotating vials at 37 degrees C for 48 h in a medium to which DMSO-dissolved test compounds had been added. This bioassay proved to be highly sensitive to dioxin-like compounds, and its usefulness for assessing the toxic potency of such compounds in environmental samples was demonstrated. Concentration-response curves were determined for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-penlachlorobiphenyl (PCB IUPAC no. 126), 3,3',4,4'-tetrachlorobiphenyl (PCB 77), 2,3,3',4,4'-pentachlorobiphenyl (PCB 105), and benzo[k]fluoranthene (BkF). TCDD induced EROD in a concentration-dependent manner, having an EC50 of 5.0 x 10(-12) M. The cultured embryo livers were extremely sensitive to TCDD, and about 30 fg of this compound per liver (2 x 10(-13) M) was enough to significantly induce EROD. The EC50 values obtained for PCBs 126, 77, 105, and BkF were 4,4 x 10(-11) M, 9.2 x 10(-9) M, 1.6 x 10(-8) M, and 6.2 x 10(-7) M, respectively. The maximal induction levels obtained for three different preparations of polychlorinated naphthalenes (PCNs) were less than those of the other compounds tested. When the technical PCN mixture Halowax 1014 was coadministered with TCDD, the induction was lower than that caused by TCDD alone. An organic extract of fly ash from a municipal waste combustion plant was very potent. Considering its contents of polychlorinated dibenzo-p-dioxins/furans, expressed as TCDD equivalents, the EC50 obtained was close to that for TCDD.
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3.
  • Engwall, Magnus, 1965-, et al. (author)
  • 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
  • In: Marine Pollution Bulletin. - 0025-326X .- 1879-3363. ; 34:12, s. 1032-1040
  • Journal article (peer-reviewed)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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4.
  • Engwall, Magnus, 1965-, et al. (author)
  • 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
  • In: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 16:6, s. 1187-1194
  • Journal article (peer-reviewed)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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5.
  • Engwall, Magnus, 1965-, et al. (author)
  • Toxic potencies of lipophilic extracts from sediments and settling particulate matter (SPM) collected in a PCB-contaminated river system
  • 1996
  • In: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 15:2, s. 213-222
  • Journal article (peer-reviewed)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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8.
  • Hansson, Tomas, et al. (author)
  • Cytological and biochemical biomarkers in adult female perch (Perca fluviatilis) in a chronically polluted gradient in the Stockholm recipient (Sweden)
  • 2014
  • In: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 81:1, s. 27-40
  • Journal article (peer-reviewed)abstract
    • By measuring a battery of cytological and biochemical biomarkers in adult female perch (Perca fluviatilis), the city of Stockholm (Sweden) was investigated as a point source of anthropogenic aquatic pollution. The investigation included both an upstream gradient, 46 km westwards through Lake Malaren, and a downstream gradient, 84 km eastwards through the Stockholm archipelago. Indeed, there was a graded response for most of the biomarkers and for the muscle concentrations of Sigma PBDE, four organotin compounds and PFOS in the perch. The results indicated severe pollution in central Stockholm, with poor health of the perch, characterised by increased frequency of micronucleated erythrocytes, altered liver apoptosis, increased liver catalase activity, decreased brain aromatase activity, and decreased liver lysosomal membrane stability. Some biomarker responses were lowest in the middle archipelago and increased again eastwards, indicating a second, partly overlapping, gradient of toxic effects from the Baltic Sea.
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9.
  • Ishaq, R., et al. (author)
  • PCNs, PCDD/Fs, and Non-orthoPCBs, in Water and Bottom Sediments from the Industrialized Norwegian Grenlandsfjords
  • 2009
  • In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:10, s. 3442-3447
  • Journal article (peer-reviewed)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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12.
  • Linderoth, Maria, et al. (author)
  • Sex steroids in the female zebrafish (Danio rerio). Effects of cyproterone acetate and leachate-contaminated sediment extract
  • 2006
  • In: Aquatic Toxicology. - : Elsevier B.V. - 0166-445X .- 1879-1514. ; 79:2, s. 192-200
  • Journal article (peer-reviewed)abstract
    • In Molnbyggen, a leachate-contaminated lake in Sweden, effects on the reproductive system of perch included a decreased frequency of sexually mature female perch, reduced gonadosomatic index and decreased plasma levels of androstenedione and testosterone, but the contaminants responsible for these effects have not yet been identified. A biomarker-directed fractionation approach could be used to narrow the search for the compound(s) responsible for the adverse effects in Molnbyggen female perch. Thus, it is important to develop and test a suitable biomarker, which can be used in this type of approach. We evaluated if decreased concentrations of sex steroids could work as an in vivo end-point in female zebrafish fed an organic extract of bottom sediments from Molnbyggen. The responsiveness of zebrafish to endocrine alteration was evaluated using a positive control substance, cyproterone acetate (CA), which is known to inhibit steroid biosynthesis. After the 21-day exposure period the concentrations of testosterone (T) and estradiol (E2) were successfully determined by HRGC/HRMS in whole-body homogenates of individual fish. Median T concentrations were 1.7 pmol/g fish in controls and were decreased after exposure both to CA (0.55 pmol/g fish) and Molnbyggen sediment extract (1.2–1.3 pmol/g fish). Median E2 concentrations were 5.3 pmol/g fish in controls and were decreased after CA exposure (2.3 pmol/g fish) and after exposure to Molnbyggen sediment extract (4.0–4.5 pmol/g fish). This suggests that sex steroid concentrations in zebrafish are responsive to endocrine alteration and indicates that compounds with endocrine altering potency are present in Molnbyggen sediments.
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13.
  • Linderoth, Maria, et al. (author)
  • Steroid biosynthetic enzyme activities in leachate-exposed female perch (Perca fluviatilis) as biomarkers for endocrine disruption
  • 2006
  • In: Science of the Total Environment. - : Elsevier B.V.. - 0048-9697 .- 1879-1026. ; 366:2-6, s. 638-648
  • Journal article (peer-reviewed)abstract
    • Studies have shown that adult female perch in a freshwater lake, Molnbyggen, Sweden, have a reproductive disorder caused by unidentified endocrine disrupting compounds (EDCs) leaching from a local refuse dump. The adverse effects include shallow open sores, low ratio of sexually mature individuals, low gonadosomatic index and low circulating levels of androgens. We hypothesised that the low androgen levels could be a result of impaired production and/or stimulated excretion of androgens by EDCs. From October 2000 to November 2001, at time-points important in the perch reproductive cycle, adult female perch were collected in Molnbyggen and in the reference lake, Djursjön. The activities of three key enzymes in androgen biosynthesis: 17α-hydroxylase (17OHlase), 17,20-lyase (lyase) and 17β-hydroxysteroid dehydrogenase (17βHSD) were determined in head kidney or ovary. The relationship between enzyme activities and plasma steroid concentrations was examined. Ovarian histopathology and the determination of brain aromatase activity were also included in the study. Similar 17OHlase, 17βHSD and aromatase activities were found in Molnbyggen females and reference fish throughout the year. Head kidney 17OHlase showed a positive correlation to cortisol levels (r = 0.754; p < 0.001) but not to androgen levels. Molnbyggen females exhibited lower ovarian lyase activity during vitellogenesis than reference fish. Atretic oocytes were on most occasions more frequent in sexually immature than in sexually mature females. The results suggest that neither 17OHlase, 17βHSD nor aromatase is the target for EDCs disrupting the androgen homeostasis of exposed female perch. Further investigation is needed to establish the role of decreased ovarian lyase activity in endocrine homeostasis, but the possibility of increased excretion of androgens should also be examined.
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14.
  • Malmvärn, Anna, et al. (author)
  • Hydroxylated and methoxylated polybrominated diphenyl ethers and polybrominated dibenzo-p-dioxins in red alga and cyanobacteria living in the Baltic Sea
  • 2008
  • In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 72:6, s. 910-916
  • Journal article (peer-reviewed)abstract
    • Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) are present in the ecosystem of the Baltic Sea. OH-PBDEs are known to be both natural products from marine environments and metabolites of the anthropogenic polybrominated diphenyl ethers (PBDEs), whereas, MeO-PBDEs appear to be solely natural in origin. Polybrominated dibenzo-p-dioxins (PBDDs) are by-products formed in connection with the combustion of brominated flame retardants (BFRs), but are also indicated as natural products in a red alga (Ceramium tenuicorne) and blue mussels living in the Baltic Sea. The aims of the present investigation were to quantify the OH-PBDEs and MeO-PBDEs present in C. tenuicorne; to verify the identities of PBDDs detected previously in this species of red alga and to investigate whether cyanobacteria living in this same region of the Baltic Sea contain OH-PBDEs, MeO-PBDEs and/or PBDDs. The red alga was confirmed to contain tribromodibenzo-p-dioxins (triBDDs), by accurate mass determination and additional PBDD congeners were also detected in this sample. This is the first time that PBDDs have been identified in a red alga. The SigmaOH-PBDEs and SigmaMeO-PBDEs concentrations, present in C. tenuicorne were 150 and 4.6ngg(-1) dry weight, respectively. In the cyanobacteria 6 OH-PBDEs, 6 MeO-PBDEs and 4 PBDDs were detected by mass spectrometry (electron capture negative ionization (ECNI)). The PBDDs and OH-PBDEs and MeO-PBDEs detected in the red alga and cyanobacteria are most likely of natural origin.
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16.
  • Noaksson, Erik, et al. (author)
  • Gonad development and plasma steroid profiles by HRGC/HRMS during one reproductive cycle in reference and leachate-exposed female perch (Perca fluviatilis)
  • 2004
  • In: Toxicology and Applied Pharmacology. - : Elsevier BV. - 0041-008X .- 1096-0333. ; 195:2, s. 247-261
  • Journal article (peer-reviewed)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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17.
  • Noaksson, Erik, et al. (author)
  • Reproductive status in female perch (Perca fluviatilis) outside a sewage treatment plant processing leachate from a refuse dump
  • 2005
  • In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 340:1-3, s. 97-112
  • Journal article (peer-reviewed)abstract
    • Reproductive failure and endocrine disruption in female perch (Perca fluviatilis) and female brook trout (Salvelinus fontinalis), naturally exposed to toxic leachate from a municipal refuse dump, has raised concerns about the reproductive status in female fish outside the sewage treatment plant (STP), which now treats the same leachate. Female perch from the receiving water, Lake Siljan, were therefore sampled in a gradient from the STP in Fornby and Österviken and compared with reference females from Isunda or Sollerön. A high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) technique enabled the analysis of circulating steroids in blood plasma: the sex steroids progesterone (P), 17α-hydroxyprogesterone (17α-OHP), androstenedione (A), testosterone (T), estrone (E1), and 17β-oestradiol (E2), the maturation-inducing hormone (MIH) 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-P), and the glucocorticoids 11-deoxycortisol (11-DC) and cortisol (C). Body and organ measurements, ratio of sexually mature (SM) females, and frequencies of body lesions, were also recorded. The percentages of SM females found in Fornby on Oct 23 (83.8%) and in Österviken on May 14 (54.0%) were lower compared with Isunda (100%). The lack of differences in gonadosomatic index (GSI) and liver-somatic index (LSI) indicated a normal vitellogenesis in SM females from Fornby and Österviken. No differences in circulating levels of steroids were observed between the sites, except at the time of spawning, when elevated P and 17α-OHP levels in females from Österviken indicated a steroidogenic shift from the synthesis of sex steroids towards the production of the MIH 17α,20β-P. The significant peak-levels of both 17α,20β-P and 11-DC in female perch from Österviken at the same time suggest that both are involved in controlling final oocyte maturation in perch. The elevated levels of androgens (A and T) in females caught on the same occasion in Fornby implied that these females were at an earlier stage of oocyte maturation, prior to the steroidogenic shift towards MIH-production. This study confirms the results of an earlier study revealing low numbers of SM female perch outside the STP in Fornby. The lack of associated effects on organ indexes and circulating levels of steroids does not indicate exposure to endocrine disrupting substances (EDSs) from the treated sewage. The consistently high numbers of SM females in the northern part of Siljan suggest, however, that natural factors are not responsible for the reproductive failures in the southern part of the lake.
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18.
  • Nordlöf, Ulrika, et al. (author)
  • Comparison of organohalogen compounds in a White-tailed sea eagle egg laid in 1941 with five eggs from 1996-2001
  • 2012
  • In: Chemosphere. - : Elsevier. - 0045-6535. ; 88, s. 286-291
  • Journal article (peer-reviewed)abstract
    • Eggs laid by white-tailed sea eagles (Haliaeetus albicilla), one in 1941 and five eggs between 1996 and 2001, all from the same geographical region of the Baltic Sea, were screened for organohalogen substances. The 1941 egg contained hexachlorobenzene (HCB), but did not contain either of the pesticides hexachlorocyclohexane (HCH) or p,p0-DDT, nor any metabolites of the latter. In contrast, the more recent eggs (REs) contained all of these compounds. Of the seven polychlorinated biphenyls (PCBs) analyzed (CB28, 52, 101, 118, 138/163, 153 and 180), only the more highly chlorinated congeners were detected in the 1941 sample, with CB153 followed by CB180 showing the highest concentrations. All eggs demonstrated the same congener pattern with respect to the more highly chlorinated PCBs, but concentrations were approximately 70–230 times higher in the REs. All of the polychlorinated-p-dioxin and dibenzofuran (PCDD/Fs) congeners analyzed were detected in the eggs, with the dominant congener being 2,3,4,7,8-PeCDF (1250 pg/g l.w. in 1941 and 1540 pg/g l.w. (GM) for the REs, respectively). None of the other congeners exceeded 400 pg/g l.w., and the concentrations of 2,3,7,8-TCDD, 2,3,7,8-TCDF and 1,2,3,7,8-PeCDF were all lower in the REs. None of five congeners of polybrominated diphenyl ethers (PBDEs) found in the REs was detected in the egg from 1941. The three methoxylated brominated diphenyl ethers (MeO-BDEs) analyzed were found at similar levels and with a similar congener pattern in REs as in the egg from 1941. In conclusion, this study has shown the absence of DDE and PBDE and the presence of HCB and PCBs in a white-tailed sea eagle egg laid in 1941, and a strong increase of PCBs, DDE and PBDE in white-tailed sea eagle eggs from the same area in 1996–2001. The MeO-BDEs were found in similar concentrations in the analyzed eggs. The 1941 sample shows substantial concentrations of PCDD/Fs, noteworthy in the same magnitude as in the recent samples, illustrating the historical and recent exposure of these compounds
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19.
  • Nordlöf, Ulrika, 1969-, et al. (author)
  • Comparison of organohalogen compounds in a white-tailed sea eagle egg laid in 1941 with five eggs from 1996 to 2001
  • 2012
  • In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 88:3, s. 286-291
  • Journal article (peer-reviewed)abstract
    • Eggs laid by white-tailed sea eagles (Haliaeetus albicilla), one in 1941 and five eggs between 1996 and 2001, all from the same geographical region of the Baltic Sea, were screened for organohalogen substances. The 1941 egg contained hexachlorobenzene (HCB), but did not contain either of the pesticides hexachlorocyclohexane (HCH) or p,p'-DDT, nor any metabolites of the latter. In contrast, the more recent eggs (REs) contained all of these compounds. Of the seven polychlorinated biphenyls (PCBs) analyzed (CB28, -52, -101, -118, -138/-163, -153 and 180), only the more highly chlorinated congeners were detected in the 1941 sample, with CB153 followed by CB180 showing the highest concentrations. All eggs demonstrated the same congener pattern with respect to the more highly chlorinated PCBs, but concentrations were approximately 70-230 times higher in the REs. All of the polychlorinated-p-dioxin and dibenzofuran (PCDD/Fs) congeners analyzed were detected in the eggs, with the dominant congener being 2,3,4,7,8-PeCDF (1250pg/gl.w. in 1941 and 1540pg/gl.w. (GM) for the REs, respectively). None of the other congeners exceeded 400pg/gl.w., and the concentrations of 2,3,7,8-TCDD, 2,3,7,8-TCDF and 1,2,3,7,8-PeCDF were all lower in the REs. None of five congeners of polybrominated diphenyl ethers (PBDEs) found in the REs was detected in the egg from 1941. The three methoxylated brominated diphenyl ethers (MeO-BDEs) analyzed were found at similar levels and with a similar congener pattern in REs as in the egg from 1941. In conclusion, this study has shown the absence of DDE and PBDE and the presence of HCB and PCBs in a white-tailed sea eagle egg laid in 1941, and a strong increase of PCBs, DDE and PBDE in white-tailed sea eagle eggs from the same area in 1996-2001. The MeO-BDEs were found in similar concentrations in the analyzed eggs. The 1941 sample shows substantial concentrations of PCDD/Fs, noteworthy in the same magnitude as in the recent samples, illustrating the historical and recent exposure of these compounds.
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20.
  • Nordlöf, Ulrika, 1969- (author)
  • Levels of organohalogen compounds in White-tailed sea eagles (Haliaeetus albicilla) in relation to reproduction impairment in the Bothnian Sea
  • 2012
  • Doctoral thesis (other academic/artistic)abstract
    • The white-tailed sea eagle (Haliaeetus albicilla) is in the top of the marine food chain and its existence in Sweden has been threatened several times. The species succeeded to recover from the deep decline in the 1970s when the exposure to persistent organic pollutants influenced the reproduction negatively. The species is today spread over the country but is still seen as a near threatened species. Even though a recovery has occurred there is still some reproduction problems seen in the region of the south Bothnian Sea. The work presented in this thesis has focused on expanding the knowledge of bromine and chlorine containing compounds in the white-tailed sea eagles and to correlate the levels found with the reproduction impairment in the region of south Bothnian Sea. Eggs and blood from nestlings collected from different subpopulations, from the Arctic (Lapland) in the north to the Baltic Proper in the south of Sweden, have been studied for polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF), non-ortho-substituted polychlorinated biphenyl (PCB), brominated flame retardants, methoxylated- (MeO-), and hydroxylated- (OH)-polybrominated diphenyl ethers (PBDEs). Some of the investigated compounds have been compared with levels found in a unique white-tailed sea eagle egg collected in the Baltic Proper in 1941. The pattern and levels of PCDD and PCDF in 1941 were similar and in the same range as found today around the same area. Furthermore, the human activity has raised the PCB levels in the white-tailed sea eagles with over 120 times over the last 60 years but these levels are still much lower than in the 1970s. In conclusion none of the investigated compounds in this thesis could be correlated to the reduced reproduction seen in the south Bothnian Sea but the levels of PCDD, PCDF, non-ortho­-PCB and OH-PBDE are high in the populations inhabiting the Baltic Sea and are in the same range as found to cause different biological responses in other avian species worldwide.
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21.
  • Nordlöf, Ulrika, et al. (author)
  • Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho-PCBs in eggs of white-tailed sea eagles collected along the Swedish coast in the Baltic Sea
  • 2012
  • In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 438, s. 166-173
  • Journal article (peer-reviewed)abstract
    • Concentrations of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and dioxin-like non-ortho-PCBs were measured in white-tailed sea eagle (WTSE) eagle eggs collected along the Swedish coast of the Baltic Sea during the period 1992-2004. The eggs represent two different subpopulations with significantly different nestling brood sizes; the Baltic Proper (BP) with an approximately normal nestling brood size (1.62), and the south Bothnian Sea (sBS) with reduced nestling brood size (1.22) combined with a significantly higher rate of dead eggs. The aim was to investigate if this difference in reproductive outcome was linked to differences in exposure to dioxin-like compounds. Three eggs collected in Greenland in 2000 were included in the study to provide a reference sea eagle population outside of the Baltic Sea region. The concentrations of Sigma PCDD, Sigma PCDF and Sigma non-ortho-PCB in the two subpopulations from the Baltic Sea (BS) region ranged from 0.41-4.1, 1.2-5.3 and 180-970 ng/g lipids, respectively, while in the Greenland population the ranges were 0.11-0.16, 0.22-0.33 and 57-83 ng/g lipid, respectively. 2,3,4,7,8-PCDF was the predominant congener in all areas and accounted for on average 31-49% of the total Sigma PCDD/F concentrations. The total toxic equivalents (TEQ) in sBS WTSEs were higher (approximately 39 ng TEQ/g lipid) than reported in eggs for many other birds, and the major contributors to the TEQ in the Baltic Sea were the non-ortho-PCBs. A principal component analysis (PCA) showed a difference in congener pattern between the two Baltic regions that was statistically significant (Hotelling's T-2 test). We found no significant differences in the total TEQ between the two populations (sBS-BP) and thus no evidence was found linking the reproductive impairment in WTSE in sBS to the concentrations of PCDD/Fs or non-ortho-PCBs in the eggs.
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  • Widell, Bodil, 1972-, et al. (author)
  • Simultaneous determination of several natural steroids in blood plasma from perch (Perca fluviatilis) by GC-HRMS
  • Other publication (other academic/artistic)abstract
    • A gas chromatography–high resolution mass spectrometry (GC-HRMS) procedure for the simultaneous determination of 18 endogenous steroid hormones in blood plasma from teleost fish has been developed. Proteins were removed by precipitation in methanol and lipids were removed by a liquid-liquid extraction. The protein and lipid free extract was further purified by using two successive solid phase extraction (SPE) methods (C18 and NH2). The isolated steroid hormones were silylated with a mixture of N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA): iodotrimethylsilane (TMSI ):dithioerythritol (DTE) prior to determination with GC-HRMS working in selective ion recording mode. A volume of 200 mL blood plasma was sufficient for accurate determination of the steroid hormone levels, which enabled determination in individual fish. The detection limits ranged from 0.0003 to 0.2 ng/g blood plasma from perch (Perca fluviatilis), approximately 10 to 100 times lower then previously reported in this field. The recoveries for the entire procedure were in the range 58 to 150% with a variation, expressed as standard deviation (SD), below 10% with some exceptions. Despite the multi-step clean-up procedure, the intra-assay coefficient of variation, i.e. the within-day variation, for most steroid hormones was well below 14%. Finally, the procedure has been successfully applied to the determination of steroid hormones in blood plasma from female perch caught in two Swedish lakes.
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27.
  • Widell, Bodil, et al. (author)
  • Simultaneous determination of several natural steroids in blood plasma from perch (Perca fluviatilis) by GC-HRMS
  • 2011
  • In: International Journal of Environmental Analytical Chemistry. - : Informa UK Limited. - 0306-7319 .- 1029-0397. ; 91:4, s. 303-318
  • Journal article (peer-reviewed)abstract
    • Agas chromatography-high resolution mass spectrometry (GC-HRMS) procedure for the simultaneous determination of 18 endogenous steroid hormones in blood plasma from teleost fish has been developed. Proteins were removed by precipitation in methanol and lipids were removed by a liquid-liquid extraction. The protein and lipid free extract was further purified by using two successive solid phase extraction (SPE) methods (C18 and NH(2)). The isolated steroid hormones were silylated with a mixture of N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA): iodotrimethylsilane (TMSI): dithioerythritol (DTE) prior to determination with GC-HRMS working in selective ion recording mode. A volume of 200 mu L blood plasma was sufficient for accurate determination of the steroid hormone levels, which enabled determination in individual fish. The detection limits ranged from 0.0003 to 0.2 ng g(-1) blood plasma from perch (Perca fluviatilis), approximately 10 to 100 times lower then previously reported in this field. The recoveries for the entire procedure were in the range 58 to 150% with a variation, expressed as standard deviation (SD), below 10% with some exceptions. Despite the multi-step clean-up procedure, the intra-assay coefficient of variation, i.e. the within-day variation, for most steroid hormones was well below 14%. Finally, the procedure has been successfully applied to the determination of steroid hormones in blood plasma from female perch caught in two Swedish lakes.
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28.
  • Zebühr, Yngve, 1943- (author)
  • Trace analysis of polychlorinated dibenzo-p-dioxines, dibenzofurans and related compounds in environmental matrices
  • 1992
  • Doctoral thesis (other academic/artistic)abstract
    • In this thesis sample extraction, clean up procedures and quantitative and qualitative analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and related compounds are discussed, as well as aspects on the sampling of some complex environmental matrices.The matrices are mostly from the aquatic environment but other samples are also dealt with, such as urban and remote air samples, samples from environments with heavy automobile traffic and samples from one municipal incinerator, waste water treatment plants etc.The samples from the aquatic environment represent both heavily contaminated matrices such as settling particulate matter from areas off various industries and in central Stockholm, and complex biological matrices such as bivalves, fish and birds.The thesis describes the different steps of the cleaning up procedure in detail. New automated methods for handling complicated samples are further discussed. A new method which was used for most of the samples prepares all the fractions for analysis on high resolution GC, medium resolution MS and GC-mass selective detector.Another central part of the work in this thesis is the aim to analyse as many as possible of the components of interest in the same sample. This gives more precise answers to the questions asked, reduces the number of samples and last but not least, saves time. The essence of this method is a HPLC-method which uses an amino column for fractionation of the sample according to the aromaticity, in combination with a GCP-column which has high selectivity for aromatic and related compounds. The fractions are collected both using a heart-cutting mode and a back-flushing technique.
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