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Hanno Zielke Thomas-Benjamin Seiler Sabine Niebergall Erik Leist Markus Brinkmann Denise Spira Georg Streck Werner Brack Ute Feiler Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2011,11(2):352-363
Purpose
Traditionally, methods for sediment extractions are characterised using chemical analyses. However, in order to evaluate sediment extracts with regard to biological effects and, thus, bioaccessibility, extraction methods have to be compared to effect data obtained from experiments with in situ exposure scenarios, i.e., sediment contact tests. This study compares four extraction methods and sediment contact test data from a previous project with respect to predictive power in the fish embryo test with zebrafish (Danio rerio).Materials and methods
A natural and an artificial sediment spiked with a mixture of six organic pollutants (2,4-dinitrophenol, diuron, fluoranthene, nonylphenol, parathion and pentachlorophenol) were extracted using (a) membrane dialysis extraction (MDE), (b) a Soxhlet procedure, (c) hydroxypropyl-??-cyclodextrin (HPCD) or (d) Tenax®-TA. Whereas the former two are regarded being exhaustive with respect to non-covalently bound contaminants, the latter two are considered to predict bioaccessibility. Resulting extracts were tested in the fish embryo assay with D. rerio for embryotoxic and teratogenic potential.Results and discussion
Mortalities caused by organic extracts from Soxhlet extraction and MDE were high. However, HPCD extracts turned out to be at least as effective as extracts obtained with these two methods. One possible reason might be short ageing time of the spiked sediments. Only Tenax®-TA extracts gave results comparable to the sediment contact assay for natural sediment, but revealed low reproducibility. Significant differences between natural and artificial sediment were found for extracts obtained with techniques using native (i.e., non-freeze-dried) sediments, i.e., HPCD and Tenax®-TA. In contrast, MDE and Soxhlet extracts used freeze-dried sediment and did not differentiate between natural and artificial sediment. Therefore, freeze-drying has likely altered and equalised sediment properties that influence accessibility, such as composition of bacterial communities and organic matter quality.Conclusions
Four extraction methods were successfully characterised with respect to their stringency and predictiveness for bioaccessibility. MDE was confirmed as an alternative to Soxhlet extraction. High mortalities induced by HPCD extracts underline the need to include ageing into consideration when assessing sediments. Although Tenax®-TA may basically be used to predict bioaccessibility in the fish embryo test, the high variability observed warrants further investigation of the relation between effect and extractability. Apparently, freeze-drying can severely affect sediment properties, potentially eliminating individual properties of natural sediments. 相似文献2.
Physiological reactions of spruce (Picea abies) on complex SO2- and drought-induced stress. Part 3. Responses of SO2-stressed spruces to subsequent drought-induced stress. SO2-stressed spruces under drought-stress showed less reduced water content, less increased osmotical potential and less restricted photosynthesis compared to spruces without preceding SO2-stress and thus seemed to be in a better physiological situation. Their ability to retain water (in cut-off twigs) as well as their ability to withstand a quick and strong water-loss in the needle-tissue without cell-damage were reduced. Reasons for the temporarily favourable effect of a pre-going SO2-stress in surviving a drought-stress are discussed. 相似文献
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Steffen Keiter Sabrina Peddinghaus Ute Feiler Britta von der Goltz Christoph Hafner Nga Yu Ho Sepand Rastegar Jens C. Otte Richard Ottermanns Georg Reifferscheid Uwe Strähle Thomas Braunbeck Monika Hammers-Wirtz Henner Hollert 《Journal of Soils and Sediments》2010,10(4):714-717
Introduction
The European Water Framework Directive aims to achieve a good ecological and chemical status in surface water of European rivers by the year 2015. Since sediments and particulate matter act as secondary sources for pollutants, applied sediment toxicology is perceived to play a major role for obtaining new knowledge that can contribute to successful attainment of the goal. However, the existing bioassays for sediment toxicity analyses do not provide sufficient data concerning bioavailability of environmental pollutants. In this regard, there is an urgent need to combine sediment contact assays with gene expression analysis to investigate mechanism-specific sediment toxicity.Purpose
The aim of the novel joint research project is to develop a eukaryotic test system, which can be used to investigate the ecotoxicological effects of contaminated sediments on gene expression level (DNA-array and RT-PCR). Current ecotoxicological research customarily involves a battery of bioassays to cover different toxicological endpoints (e.g., teratogenicity, genotoxicity, mutagenicity, Ah-receptor-mediated toxicity, neurotoxicity). In contrast, methods that detect alterations in gene expression offer deeper insight by elucidating how chemical exposure and/or environmental challenge affect multiple metabolic pathways leading to these particular kinds of toxic response. Gene expression profiles reflect the way cells and organisms adapt or respond to a changing environment.Conclusion
The present project aspires to increase the fundamental molecular and physiological knowledge concerning the mode of action of environmental toxicants in zebrafish (Danio rerio). By working with partners from the academic and research institutions as well as from industry and waterway regulations, the success of this basic research-driven joint project in terms of development and implementation of novel sediment toxicity methods will be realized. 相似文献5.
Danijela Stesevic Ute Feiler Danijela Sundic Slavoljub Mijovic Lothar Erdinger Thomas-Benjamin Seiler Peter Heininger Henner Hollert 《Journal of Soils and Sediments》2007,7(5):342-349
Goal, Scope and Background Situated in the transboundary belt between Montenegro and Albania, Lake Skadar is the largest freshwater reservoir in Southeastern
Europe. Because of the wide range of endemic, rare or endangered plant and animal species it supports, Lake Skadar and its
extensive adjacent wetlands are internationally recognised as a site of significance and importance (Ramsar site). Within
the last 10 to 20 years, Lake Skadar was exposed to intensive pollution. For the assessment of the ecotoxic load of the sediments
sampled in Lake Skadar, a triad approach was recently applied. Overall, a complex spectrum of ecotoxic loads was elucidated.
The aim of the present study was to use plant-based bioassays for assessing the sediment quality of Lake Skadar in order to
facilitate and complement the triad test battery. The newly developed sediment contact test with Myriophyllum aquaticum and the aquatic growth inhibition test with Lemna minor were applied to native sediments and pore water, respectively, allowing the investigation of different toxicity-effects caused
by particle-bound pollutants as well as pollutants in the interstitial water. This investigation is the first application
of the novel sediment contact test with Myriophyllum aquaticum to lake sediments.
Methods Sediment samples were taken from nine selected sites at Lake Skadar and investigated by the sediment contact assay with Myriophyllum aquaticum. The pore water was extracted from these sediment samples to be analysed in the aquatic growth inhibition test with Lemna minor. The results of the sediment contact tests were compared with each other and with those of the aquatic growth inhibition
test.
Results and Discussion Both applied macrophyte biotests revealed distinct changes in the growth behaviour of the two macrophytes subsequent to the
exposure to the investigated natural sediments of Lake Skadar. The Myriophyllum sediment contact test revealed significant toxicity in the sediment samples from Radus and Kamenik, whereas the aquatic Lemna test showed inhibition effects for the samples from Sterbeq, Plavnica and Kamice. Data obtained with the newly developed
Danio rerio contact test and the Arthrobacter globiformis contact test confirmed the Myriophyllum results.
Analyses of the heavy metal content in the sediments revealed low or moderate contamination levels. Correlation analyses between
the content of heavy metals in the sediments and growth inhibition of Myriophyllum aquaticum showed a significant correlation between Cr concentrations and growth inhibition. Comparable findings are available for a
German river system. In contrast, no significant correlation between inhibition rates and concentration of metals could be
observed with Lemna minor.
Conclusions It was shown that the newly developed sediment contact test with Myriophyllum aquaticum is applicable to lake sediments. In both the sediment contact test with Myriophyllum aquaticum on whole sediments and the aquatic growth inhibition test with Lemna minor on pore water, plant growth was influenced by the natural sediments and its components. Therefore, both test systems were
found to be suitable for the detection of phytotoxic effects upon exposure to sediments. Myriophyllum aquaticum as test organism of the contact test grows directly in the sediment without an additional water-layer. Thus, it is able to
detect toxicity caused by particle-bound phytotoxic substances as well as pore water-related contamination, while the floating
Lemna minor can only detect effects emanating from pore water. Significant differences of the results were observed between these two
test systems and, accordingly, the two different exposure scenarios. Hence, none of the tests can replace the other one and,
as a consequence, both should be included into a test battery for the assessment of sediment toxicity.
Recommendations and Perspectives Both plant assays were shown to be reliable tools for the evaluation of the eco-toxicological risk potentials of pore water
and solid-phase sediment. They should become a complement to the standardised test battery generally used for comprehensive
hazard assessment.
ESS-Submission Editor: Dr. Ulrike Kammann (ulrike.kammann@ifo.bfa-fisch.de) 相似文献
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Heise Susanne Babut Marc Casado Carmen Feiler Ute Ferrari Benoit J. D. Marziali Laura 《Journal of Soils and Sediments》2020,20(12):4218-4228
Purpose
Basing decisions for the management of contaminated sediments on ecotoxicological data is still often met with skepticism by European stakeholders. These concerns are discussed as they pertain to bioassays to show how ecotoxicological data may provide added value for the sustainable management of sediment in aquatic systems.
Materials and methodsFive “concerns” are selected that are often raised by stakeholders. The ecotoxicological practice is discussed in light of the knowledge gained in recent decades and compared with chemical sediment analysis and chemical data.
Results and discussionCommon assumptions such as a higher uncertainty of biotest results for sediments compared to chemical analyses are not supported by interlaboratory comparisons. Some confusion also arises, because the meaning of biotest data is often misunderstood, questioning their significance in light of a limited number of organisms and altered test conditions in the lab. Because biotest results describe a sediment property, they should not be directly equated with an impact upon the biological community. To identify a hazard, however, the possibility of false-negative results due to the presence of contaminants that are not analyzed but are toxic is lower.
ConclusionsThe cost of increased investment in ecotoxicological tests is, in our view, small compared with that of making false-negative assessments of sediment/dredged material that can ultimately have long-term environmental costs. As such, we conclude that ecotoxicological testing is an opportunity for sediment management decision-making that warrants more attention and confidence in Europe.
相似文献8.
René Schreiber Anette Küster Ute Feiler Matthias Grote Rolf Altenburger 《Journal of Soils and Sediments》2011,11(8):1419-1431
Purpose
The objective of this study was to modify a sediment contact protocol to a multiwell plate exposure system which supplements measurement of the fresh weight change (FWC) using the non-invasive effective quantum yield of energy conversion at photosystem II (PS II) reaction centres (Y(II)) in parallel. Since Y(II) is a functional parameter and FWC represents a whole-plant structural response, the determination of a more pronounced response in one of these parameters may hint at the mode of action of contaminants. By the observation of Y(II) at different time points, extrapolation of effect development over time may be gained from modelling. 相似文献9.
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David Gidoni Moshe Bar Baruch Leshem Nehama Gilboa Anahit Mett Julia Feiler 《Euphytica》2001,121(2):145-156
FLP site-specific recombination has been shown in transgenic plants to excise DNA sequences between target FRT sites, and thereby activate transgenes in plants. In previous reports, crossing of tobacco plants expressing FLP recombinase
from a CaMV-35s promoter with plants containing the target FRT sites, hybrid plants with deletion sectors were generated, which were infrequently transmitted to progeny. In this report
we evaluate the occurrence of recombination in F1 hybrid seed derived from crosses of different FLP and FRT-reporter target lines and the germinal transmission of recombined loci from these hybrids to F2 progeny. Twenty hybrids were generated from crosses of independent five FLP-active lines and four FRT-reporter target lines. In one hybrid, FLP deletions occurred at an early stage, prior to seed maturation, and the deletions
from this hybrid were more efficiently transmitted to F2 progeny. The demonstration of FLP-mediated recombination activity and germinal inheritance of the recombined FRT loci are supported by both molecular and enzymatic evidence.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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