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T. Braunbeck A. Brauns S. Keiter H. Hollert P. Schwartz 《Environmental Sciences Europe》2009,21(2):197-211
Background, aim, and scope Reports about declines or unusual structures of fish populations in native aquatic systems in Central Europe and North America are in sharp contrast to an obvious improvement of general water quality. The Neckar River may serve as an example of a formerly severely contaminated freshwater system in Southern Germany, the ecological situation of which could be substantially improved over the last three decades. Nevertheless, there are still deficits in the composition of the fish fauna, which cannot be explained by conventional chemical-analytical, hydromorphological and limnological methodologies. Therefore, in search of explanations for ecological deficits, ecotoxicological investigations with an increasing focus on sediment contamination have been performed along the Lower Neckar River over a period of 10 years. In addition to sediment tests, fish populations were screened for genotoxic and embryotoxic effects as well as alterations in the structure of central metabolic organs such as the liver. Materials and methods Roach (Rutilus rutilus) and gudgeon (Gobio gobio) from the Lower Neckar River were studied with respect to histo- and cytological alterations of the liver as well as the induction of genotoxicity in liver, gut, gills and blood cells by means of the comet and micronucleus assays. At the same time, both native sediments and acetonic sediment extracts were tested for toxicity to zebrafish (Danio rerio) embryos and permanent fish cell cultures. Results Massive disturbances of the liver ultrastructure indicate severe stress in the fish from the Lower Neckar River despite good supply of nutrition. Both cyto- and embryotoxicity tests document a considerable toxic potential of sediments from the Lower Neckar River, and results of both the comet assay and the micronucleus test provide evidence of the presence of genotoxic agents in the sediments and their effects in fish. There has been no decrease of genotoxicity over the last 10 years. Discussion Cytopathology in conjunction with general cyto- and embryotoxicity in fish from the Lower Neckar River contribute to a syndrome which cannot be neglected in the interpretation of abnormal compositions of fish populations. In comparison to weight-of-evidence studies at other river systems in Southern Germany, the Neckar is characterized by an elevated embryotoxic but by a relatively moderate genotoxic potential. Conclusions The ecotoxicological burden of sediments at the Lower Neckar River is mirrored in the condition of native fish populations. A potential contribution of chemical contamination to the phenomenon of fish declines in aquatic ecosystems cannot be ignored. Recommendations and perspectives The improvement of the ecological status of freshwater systems may not be abused as an argument to discontinue biological monitoring programs. Rather, continuous surveillance of the environment and in-depth investigations into the consequences of chemical contamination are indispensible. For an adequate appreciation of the ecological relevance of sublethal and/or specific biological effects, their impact on population structure and function remains to be elucidated further. For the identification of the chemical basis of biological effects, methodologies such as effect-directed analysis appear to be promising approaches. 相似文献
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Henner Hollert Sebastian Hudjetz Evelyn Claus Werner Manz Georg Reifferscheid Peter Heininger Jan Schwarzbauer Wolfgang Ahlf Thomas Braunbeck Werner Brack Tobias Schulze Andreas Sch?ffer und Hans-Toni Ratte 《Umweltwissenschaften und Schadstoff-Forschung》2009,21(3):235-237
Ohne Zusammenfassung
Verantwortliche Herausgeber: Jan Schwarzbauer · Peter Heininger · Evelyn Claus
相似文献
Henner Hollert (Corresponding author)Email: |
Evelyn ClausEmail: |
Peter HeiningerEmail: |
Jan SchwarzbauerEmail: |
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Kerstin Ulrich Sabine Wölfle Anja Mayer Klaus Heeg Thomas Braunbeck Lothar Erdinger Holger Bartz 《Environmental science and pollution research international》2010,17(6):1257-1267
Background, aim, and scope
Lungs are permanently and simultaneously challenged by airborne microorganisms and airborne pollutants. Temporal increase of airborne particulate matter (APM), a potential carrier for extractable organic matter (EOM), degrades the situation of pulmonary patients. The Ah receptor (AhR) has been described as an important factor influencing the immunological challenge by viral infections. Molecular mechanisms underlying epidemiological observations are not well understood. Cytokine secretion (IL-6, IL-8, and TGF-β) from human bronchial epithelial cells (Beas2B) was determined as an indicator for immune responses upon co-stimulation with an artificial analog of viral dsRNA [polyinosinic/polycytidylic acid, (PIC)] and EOM of Standard Reference Material 1649a (SRM). Since polycyclic aromatic hydrocarbons are major components of APM usually acting via the AhR, particular focus was on AhR involvement. 相似文献25.
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Henner?HollertEmail author Ingo?Haag Matthias?Dürr Bernhard?Wetterauer Roman?Holtey-Weber Ulrich?Kern Bernhard?Westrich Harald?F?rber Lothar?Erdinger Thomas?Braunbeck 《Environmental Sciences Europe》2003,15(1):5-12
Particle-bound pollutants accumulate in river-bottom sediments, a process which results in a significant decrease in the ecotoxicological availability of toxicants for the majority of aquatic organisms. Under normal hydrologic conditions, the release of contaminants from bottom sediments is usually of minor importance. In contrast, flood events may remobilize highly contaminated sediments via in-stream erosion. The objective of this study was to develop a combined ecotoxicological and hydraulic approach to elucidate the ecotoxicological implications associated with the risk of erosion of contaminated sediments. This integrated strategy was applied to the lock-regulated Neckar river in Southern Germany. Both the bottom-sediment cores and suspended matter from two intensive flood events were investigated. Sediment samples below an erosional unconformity showed a sharp increase in the ecotoxicological load. Moreover, it was found that major flood events (HQ5 and higher) could possibly erode even very old, well-consolidated and highlycontaminated sediments. The suspended matter of the high discharge events investigated (return periods of 15 to 20 years) exerted significantly higher cytotoxicity and mutagenicity than a moderate flood with a 1-year return period. These findings support the conclusion that the observed ecotoxicological effects during major floods may at least in part be due to the in-stream erosion of highly contaminated bottom sediments. 相似文献
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Tobias Schulze Bernhard Wetterauer Jan Schwarzbauer Henner Hollert Thomas Braunbeck Mathias Ricking 《Environmental Sciences Europe》2003,15(2):71-77
Sediment samples from rivers and lakes of Berlin (Germany) were analysed for their contamination with organic compounds by means of qualitative and quantitative GC/MS analysis. The principal compounds detected were PAH, organotin derivates, several classes of chlorinated, brominated and mixed halogenated compounds and some of their related metabolites. The DDT metabolites DDD, DDE, DDCN, DDMU and DDMS were the most abundant compounds of halogenated pesticides in a wide range of samples. The main metabolite determined was p,p′-DDD, with concentrations up to 1230 μg/kg dw. The parent DDT compound was detected in only a few samples. The acute cytotoxicity of selected DDT-metabolites was determined with the permanent cell line RTG-2 from the gonads of the rainbow trout (Oncorhynchus mykiss). The results indicate a high cytotoxic potential of these metabolites. The oestrogenic potential was determined by the Dot-Blot/RNase-Protection-Assay an the order from o,p′-DDT>p,p′-DDMS>p,p′-DDMU≥p,p′-DDCN. Risk assessments based on chemical analysis of DDT, DDD and DDE alone is not able to estimate the real toxic potential of DDT and its metabolites. The development of a method for bioassay directed assessment seems to be an effective strategy to solve this problem. Especially scarce or not available data of combinatory effects, differences between different trophic levels and their availability to biota and low knowledge about the metabolism in situ as well as the enantioselective characteristics of most chiral DDT metabolites warrant future analyses. 相似文献
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Klee N Gustavsson L Kosmehl T Engwall M Erdinger L Braunbeck T Hollert H 《Environmental science and pollution research international》2004,11(5):313-320