title: A comparative approach using ecotoxicological methods from single-species bioassays to model ecosystems.
abstract: Soft sediments are often hotspots of chemical contamination, and a thorough ecotoxicological assessment of this habitat can help to identify the causes of stress and to improve the health of the respective ecosystems. As an important component of the ecologically relevant meiobenthic fauna, nematodes can be used for sediment assessments, with various assay tools ranging from single-species toxicity tests to field studies. In the present study, microcosms containing sediment were used to investigate direct and indirect effects of zinc on natural nematode assemblages, and acute community toxicity tests considering only direct toxicity were conducted. The responses of the various freshwater nematode species in both approaches were compared with those of Caenorhabditis elegans, determined in standardized tests (ISO 10872). At a median lethal concentration (LC50) of 20 mg Zn/L, C. elegans represented the median susceptibility of 15 examined nematode species examined in the acute community toxicity tests. In the microcosms, Zn affected the nematodes dose-dependently, with changes in species composition first detected at 13 mg Zn/kg to 19 mg Zn/kg sediment dry weight. The observed species sensitivities in the microcosms corresponded better to field observations than to the results of the acute community toxicity tests. Environ Toxicol Chem 2016;35:2987-2997. © 2016 SETAC.
authors.affiliation: Department of Animal Ecology, University of Bielefeld, Bielefeld, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Haegerbaeumer
authors.affiliation: Ecological Sediment and Soil Assessment, Starnberg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Höss
authors.affiliation: Department of Animal Ecology, University of Bielefeld, Bielefeld, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Ristau
authors.affiliation: German Federal Institute of Hydrology, Koblenz, Germany.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Claus
authors.affiliation: German Federal Institute of Hydrology, Koblenz, Germany.
authors.forename: Christel
authors.initials: C
authors.lastname: Möhlenkamp
authors.affiliation: German Federal Institute of Hydrology, Koblenz, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Heininger
authors.affiliation: Department of Animal Ecology, University of Bielefeld, Bielefeld, Germany.
authors.forename: Walter
authors.initials: W
authors.lastname: Traunspurger
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D001681:Biological Assay; D017173:Caenorhabditis elegans / Q000187:drug effects* / Q000378:metabolism; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D019015:Geologic Sediments / Q000737:chemistry*; D007928:Lethal Dose 50; D009348:Nematoda / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D023382:Toxicity Tests, Acute / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D015032:Zinc / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D002734:Chlorophyll; D000255:Adenosine Triphosphate; D015032:Zinc; D000077194:Chlorophyll A
keywords: Caenorhabditis elegans; Microcosms; Nematodes; Sediment toxicity; Zinc