PARENT SESSION

2K - Sediment Assays
Poster Hall
8:30 AM - Tuesday, 29 April 2003

(TUP/149) Combined use of nematodes and snails in eco(toxico)logical sediment assessment – from laboratory experiments to field monitoring.

Duft, Martina¹, Tillmann, Michaela¹, Traunspurger, Walter², Schulte-Oehlmann, Ulrike³, Oehlmann, Jörg³, ¹ International Graduate School (IHI), Zittau, Germany, Germany² University of Bielefeld, Bielefeld, Germany, Germany³ J.W. Goethe University, Frankfurt/Main, Germany, Germany

ABSTRACT- At present, only few test systems are available for the routine assessment of adverse effects on invertebrates exposed to whole sediments. In this study, three methods for the evaluation of sediment quality were investigated and their suitability for sediment toxicity assessment was evaluated: (1) the well-established bioassay with the nematode Caenorhabditis elegans covering effects on growth, fertility and reproduction, (2) the newly developed bioassay with the freshwater mudsnail Potamopyrgus antipodarum, to test for (endocrine) effects on reproduction, and (3) the composition of the natural nematode community as ecological parameter. With the two bioassays, we tested the effects of various chemicals (heavy metals, PAH, xeno-androgens and xeno-estrogens) in environmentally relevant concentration ranges in the laboratory. Besides, the influence of abiotic parameters (organic carbon content, salinity, grain size) on the toxicological endpoints was studied. Finally, the combination of the three test systems was used to examine 200 natural sediment samples from 12 large German rivers, varying in their degree of contamination. Based on the obtained data, statistically-derived concepts for the assessment and classification of sediments, according to the water framework directive of the EU, were developed and applied. Correlations and factor analyses revealed that each of the three methods provides different information, which suggests the application of all test systems gives a better reflection of the overall sediment quality.

Key words: bioassay, sediment, nematodes, prosobranch snails