Title:
Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds.
Authors:
Sebastian Hoess, Wolfgang Ahlf, Christiane Fahnenstich, Daniel Gilberg, Henner Hollert, Kerstin Melbye, Michael Meller, Monika Hammers-Wirtz, Peter Heininger, Helga Neumann-Hensel, Richard Ottermanns, Toni Ratte, Thomas-Benjamin Seiler, Denise Spira, Jürgen Weber & Ute Feiler
Year:
2010
Bibl. details:
Environmental Pollution 158 (2010) 2999 - 3010
Keywords:
Sediment, Contact test, Toxicity threshold, Test variability, Test battery, Oligochaetes, Lumbriculus variegatus, Arthrobacter globiformis, Saccharomyces cerevisiae, Caenorhabditis elegans, Myriophyllum aquaticum, Danio rerio
Abstract
Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity.
