title: Investigations on sediment toxicity of German rivers applying a standardized bioassay battery.
abstract: River sediments may contain a huge variety of environmental contaminants and play a key role in the ecological status of aquatic ecosystems. Contaminants adsorbed to sediments and suspended solids may contribute directly or after remobilization to an adverse ecological and chemical status of surface water. In this subproject of the joint research project DanTox, acetonic Soxhlet extracts from three German river sediments from the River Rhine (Altrip and Ehrenbreitstein with moderate contamination) and River Elbe (Veringkanal Hamburg heavily contaminated) were prepared and redissolved in dimethyl sulfoxide (DMSO). These extracts were analyzed with a standard bioassay battery with organisms from different trophic levels (bacteria, algae, Daphnia, fish) as well as in the Ames test and the umuC test for bacterial mutagenicity and genotoxicity according to the respective OECD and ISO guidelines. In total, 0.01% (standard) up to 0.25% (only fish embryo test) of the DMSO sediment extract was dosed to the test systems resulting in maximum sediment equivalent concentrations (SEQ) of 2 up to 50 g l(-1). The sediment of Veringkanal near Hamburg harbor was significantly more toxic in most tests compared to the sediment extracts from Altrip and Ehrenbreitstein from the River Rhine. The most toxic effect found for Veringkanal was in the algae test with an ErC50 (72 h) of 0.00226 g l(-1) SEQ. Ehrenbreitstein and Altrip samples were about factor 1,000 less toxic. In the Daphnia, Lemna, and acute fish toxicity tests, no toxicity at all was found at 2 g l(-1) SEQ. corresponding to 0.01% DMSO. Only when increasing the DMSO concentration the fish embryo test showed a 22-fold higher toxicity for Veringkanal than for Ehrenbreitstein and Altrip samples, while the toxicity difference was less evident for the Daphnia test due to the overlaying solvent toxicity above 0.05% dimethyl sulfoxide (DMSO). The higher toxicities observed with the Veringkanal sample are supported by the PAH and PCB concentrations analyzed in the sediments. The sediment extracts of Altrip and Veringkanal were mutagenic in the Ames tester strain TA98 with metabolic activation (S9-mix). The findings allow a better ecotoxicological characterization of the sediments extensively analyzed in all subprojects of the DanTox project (e.g., Garcia-Kaeufer et al. Environ Sci Pollut Res. doi: 10.1007/s11356-014-3894-4 , 2014; Schiwy et al. Environ Sci Pollut Res. doi: 10.1007/s11356-014-3185-0 , 2014; Hollert and Keiter 2015). In the absence of agreed limit values for sediment extracts in standard tests, further data with unpolluted reference sediments are required for a quantitative risk assessment of the investigated polluted sediments.
authors.affiliation: Hydrotox GmbH, Bötzinger Straße 29, 79111, Freiburg i.Br., Germany. info@hydrotox.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Hafner
authors.affiliation: Hydrotox GmbH, Bötzinger Straße 29, 79111, Freiburg i.Br., Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Gartiser
authors.affiliation: Hydrotox GmbH, Bötzinger Straße 29, 79111, Freiburg i.Br., Germany.|Department of Ecosystem Analysis, Institute for Environmental Research, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Garcia-Käufer
authors.affiliation: Department of Ecosystem Analysis, Institute for Environmental Research, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Schiwy
authors.affiliation: Hydrotox GmbH, Bötzinger Straße 29, 79111, Freiburg i.Br., Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Hercher
authors.affiliation: Institute of Geology and Palaeontology - Applied Geology, University of Münster, Corrensstraße 24, 48149, Münster, Germany.
authors.forename: Wiebke
authors.initials: W
authors.lastname: Meyer
authors.affiliation: Institute of Geology and Palaeontology - Applied Geology, University of Münster, Corrensstraße 24, 48149, Münster, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Achten
authors.affiliation: Man-Technology-Environment Research Center, School of Science and Technology, Örebro University, 70182, Örebro, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Larsson
authors.affiliation: Man-Technology-Environment Research Center, School of Science and Technology, Örebro University, 70182, Örebro, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Engwall
authors.affiliation: Department of Ecosystem Analysis, Institute for Environmental Research, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.|Man-Technology-Environment Research Center, School of Science and Technology, Örebro University, 70182, Örebro, Sweden.
authors.forename: Steffen
authors.initials: S
authors.lastname: Keiter
authors.affiliation: Department of Ecosystem Analysis, Institute for Environmental Research, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.
authors.forename: Henner
authors.initials: H
authors.lastname: Hollert
mesh_terms: D048908:Aliivibrio fischeri; D000818:Animals; D000460:Chlorophyta; D003621:Daphnia; D054750:Ecotoxicology; D019015:Geologic Sediments / Q000737:chemistry; D007928:Lethal Dose 50; D050296:Microbial Viability / Q000187:drug effects; D012015:Reference Standards; D018570:Risk Assessment; D045483:Rivers / Q000737:chemistry; D012486:Salmonella typhimurium; D023382:Toxicity Tests, Acute / Q000379:methods* / Q000592:standards; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D015027:Zebrafish
chemical_list: D014874:Water Pollutants, Chemical
keywords: Algae growth inhibition test; Ames test; Daphnia acute toxicity test; Ecotoxicology; Fish acute toxicity test; Lemna growth inhibition test; Luminescent bacteria test; Mutagenicity; Sediment; Soxhlet extract; umuC test