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Jan Wölz Tobias Schulze Urte Lübcke-von Varel Michael Fleig Georg Reifferscheid Werner Brack Dirk Kühlers Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2011,11(1):82-92
Purpose
This study was carried out to determine hazards of particle-bound contaminants in rivers to retention areas close to public well fields in the context of flood events. The focus was on the assessment of soil contamination at a planned retention area. Soil core samples were chemically and biologically analyzed. Samples were fractionated to identify and compare contaminant loads and biological effects of soil and flood suspended particulate matter (SPM). 相似文献75.
Anthropogenic pollutants affect ecosystem services of freshwater sediments: the need for a “triad plus x” approach 总被引：1，自引：0，他引：1
Gerbersdorf Sabine Ulrike Hollert Henner Brinkmann Markus Wieprecht Silke Schüttrumpf Holger Manz Werner 《Journal of Soils and Sediments》2011,11(6):1099-1114
Purpose
Freshwater sediments and their attached microbial communities (biofilms) are essential features of rivers and lakes, providing valuable ecosystem services such as nutrient recycling or self-purification which extend beyond the aquatic environment. Anthropogenic pollutants, whether from the industrial era or as a result of our contemporary lifestyles, can negatively affect these functions with hitherto unknown consequences on ecology, the economy and human health. Thus far, the singular view of the involved disciplines such as ecotoxicology, environmental microbiology, hydrology and geomorphology has prevented a deeper understanding of this emerging issue. 相似文献76.
Thomas Kosmehl Falk Krebs Werner Manz Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2007,7(6):377-387
Goals, Scope and Background While water quality strongly improved over decades in the Rhine River, sediments still reflect elapsed contaminations of organic
pollutants and heavy metals. In comparing genotoxic effects induced by both sediment extracts and whole sediments, a ratio
of bioavailable toxicity and total extractable toxicity is obtained. Since contaminated sites whose contaminants are toxic
and as well bioavailable present an elevated risk to the ecosystem, such ratios may be used as a warning signal to identify
sites of primary concern.
Methods Accordingly, two different exposure scenarios were compared to reveal the genotoxic potential of 18 sediment samples derived
from 9 sample sites along the River Rhine. For assessment of effects on genome integrity, DNA fragmentation was measured using
the comet assay with primary cells isolated from zebrafish embryos previously exposed to either organic sediment extracts
or freeze-dried sediments at sublethal concentrations. Additionally, chemical data were used to determine responsible pollutants
and correlate them with biological effects.
Results Whereas 17 out of 18 sediment extracts caused significant DNA damage to the embryo cells, only 4 native sediments showed a
genotoxic potential. Thus, under field-like exposure conditions, a major part of potentially genotoxic compounds seem to remain
particle-bound and ineffective, as shown for whole sediment exposure. Conversely, the organic extracts seem to contain enriched
concentrations even of hardly soluble substances. Hence, organic extracts may be used as a screening tool to address potentially
polluted sites, even though the relevance of these results for the field situation may be questionable. Investigations on
native sediments determined few sites with bioavailable and therefore ecologically most relevant genotoxic sediment compounds.
Discussion However, these results may underestimate the total hazard potential of sample sites with hardly bioavailable substances. Chemical
data revealed a variety of anthropogenic pollutants, ranging from PAHs to heavy metals. Nevertheless, chemical data on the
measured priority pollutants did not fully explain the pollution pattern of the bioassays but clearly determined substances
of concern (e.g., HCB, heavy metals) in particular sample sites.
Conclusions There is a striking advantage in assessing the genotoxicity by means of different exposure scenarios that focus on either
bioavailable or extractable fractions, as the combination of the results allows obtaining information on specific properties
of the genotoxicants and their bioavailability. An additional correlation with chemical data should be required to identify
priority pollutants, as long as the responsible contaminant is known a priori. As many studies revealed inherent failures of such a correlation, an effect-driven analysis of pollutants is recommended
as a promising tool to identify even non-priority pollutants by means of their ecotoxicological effectiveness. 相似文献
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Purpose
The Three Gorges Dam project is one of the biggest projects in the world. The water level fluctuation zone (WLFZ) was created with impoundment. The purpose of the current study is to investigate the ecotoxicological potential of the sediment extracts from the WLFZ and propose future WLFZ monitoring for early detection of environmental changes brought about by pollution.Materials and methods
The investigation was performed by using cell-based in vitro bioassays to determine acute cytotoxicity (neutral red retention assay) and mechanism-specific aryl hydrocarbon receptor (AhR)-mediated activity (7-ethoxyresorufin-O-deethylase (EROD) induction assay) of sediment extracts with rainbow trout (Oncorhynchus mykiss) liver cells (RTL-W1).Results and discussion
Results showed that the cytotoxicity and AhR-mediated toxicity potential of the sediment extracts from the WLFZ in the Three Gorges Reservoir (TGR) were moderate of level compared with the ecotoxicity of sediments from other river systems. However, according to a sediment classification system in Germany, sediments from some individual sites in the WLFZ showed strong toxicity. Compared to the results from the Yangtze River in our previous study, more attention should be paid to the aryl hydrocarbon receptor inducers in the WLFZ in TGR.Conclusions
The in vitro bioassays used in this study may serve as a valuable tool to predict the potential ecological hazards of the organic pollutants in the WLFZ to the aquatic organisms in some extent.79.
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