| 1. |
- Kosmehl, Thomas, et al.
(författare)
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A combined DNA-microarray and mechanism-specific toxicity approach with zebrafish embryos to investigate the pollution of river sediments
- 2012
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Ingår i: Reproductive Toxicology. - Oxford, United Kingdom : Elsevier. - 0890-6238 .- 1873-1708. ; 33:2, s. 245-253
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Tidskriftsartikel (refereegranskat)abstract
- The zebrafish embryo has repeatedly proved to be a useful model for the analysis of effects by environmental toxicants. This proof-of-concept study was performed to investigate if an approach combining mechanism-specific bioassays with microarray techniques can obtain more in-depth insights into theecotoxicity of complex pollutant mixtures as present, e.g., in sediment extracts. For this end, altered gene expression was compared to data from established bioassays as well as to results from chemical analysis. Mechanism-specific biotests indicated a defined hazard potential of the sediment extracts, and microarray analysis revealed several classes of significantly regulated genes which could be related to the hazard potential. Results indicate that potential classes of contaminants can be assigned to sediment extracts by both classical biomarker genes and corresponding expression profile analyses of known substances. However, it is difficult to distinguish between specific responses and more universal detoxification of the organism.
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| 2. |
- Grund, Stefanie, et al.
(författare)
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Assessment of fish health status in the Upper Danube River by investigation of ultrastructural alterations in the liver of barbel Barbus barbus
- 2010
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Ingår i: Diseases of Aquatic Organisms. - Luhe, Germany : Inter-Research. - 0177-5103 .- 1616-1580. ; 23, s. 235-248
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Tidskriftsartikel (refereegranskat)abstract
- Despite intensive efforts and tightened guidelines for improvement of water quality over the last 2 decades, declines of fish populations have been reported for several rivers around the world. The present study forms part of a comprehensive weight-of-evidence approach, which aims to identify potential causes for the decline in fish catches observed in the Upper Danube River. The major focus of the present study is the investigation of the health status of wild barbel Barbus barbus L. collected from 3 locations along the Danube River, which experienced different levels of contamination. Whereas the comparison of the condition factor (CF) of field fish with that of control fish revealed no differences, ultrastructural investigations indicated severe disturbance of hepatic cell metabolism in field fish from the more contaminated sites Rottenacker and Ehingen, compared to both control fish and field fish from the less contaminated site Riedlingen. The ultrastructural analysis provided information about reactions of e.g. the rough endoplasmic reticulum, peroxisomes, andmitochondria, indicating an impaired health status of barbel at the sampling sites Rottenacker and Ehingen. Even though a straightforward cause-effect relationship between sediment contamination and ultrastructural alterations could not be established, based on a meta-analysis and toxicity assays it may be suggested that sediment-bound xenobiotics at least partly account for the hepatocellular changes. A relationship between impaired fish health status and the decline of fish catches along the Upper Danube River cannot be excluded.
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| 3. |
- Otte, Jens, et al.
(författare)
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Contribution of Priority PAHs and POPs to Ah Receptor-Mediated Activities in Sediment Samples from the RiverElbe Estuary, Germany
- 2013
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Ingår i: PLOS ONE. - San Francisco, USA : Public Library Service. - 1932-6203. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- The estuary of the River Elbe between Hamburg and the North Sea (Germany) is a sink for contaminated sediment and suspended particulate matter (SPM). One major concern is the effect of human activities on the hydrodynamics, particularlythe intensive dredging activities in this area that may result in remobilization of sediment-bound pollutants. The aim of this study was to identify pollutants contributing to the toxicological risk associated with re-suspension of sediments in the Elbe Estuary by use of an effect-directed analysis that combines chemical and biological analyses in with specific fractionation techniques. Sediments were collected from sites along the Elbe Estuary and a site from a small harbor basin of the Elbe Estuary that is known to be polluted. The sixteen priority EPA-PAHs were quantified in organic extracts of sediments. In addition, dioxin equivalents of sediments were investigated by use of the 7-ethoxyresorufin O-deethylase assay with RTL-W1 cells and the Ah receptor-mediated luciferase transactivation assay with H4IIE-luc cells. Quantification of the 16 priorityPAHs revealed that sediments were moderately contaminated at all of the sites in the Elbe River Estuary (,0.02–0.906 mg/gdw). Sediments contained relatively small concentrations of dioxin equivalents (Bio-TEQ) with concentrations ranging from15.5 to 322 pg/g dw, which were significantly correlated with dioxin equivalents calculated based on toxicity referencevalues and concentrations of PAH. The concentration of Bio-TEQ at the reference site exceeded 200,000 pg/g dw. In apotency balance the 16 PAHs explained between 47 and 118% of the Bio-TEQ in the luciferase assay, which can be explained by the constant input of PAHs bound to SPM from the upper course of the Elbe River into its estuary. Successful identification of a significant portion of dioxin-like activity to priority PAHs in complex environmental samples such assediments has rarely been reported.
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