TA6 Applications of Ecotoxicology to Real World Problems
Room 18A/B, Level 4
8:00 AM - 12:00 PM, Tuesday, 11 November 2003
Chair: Williams, Bill ,
(216) Relative Sensitivity Distributions (RSD) of Aquatic Invertebrates - A tool to improve Risk Assessment in the field.
von der Ohe, Peter Carsten1, Liess, Matthias1, 1 UFZ Centre for Environmental Research, Leipzig, Germany
ABSTRACT- In the field a multitude of species can be exposed to numerous toxicants. To predict the effects of toxicants and to understand changes in species composition in communities it is therefore desirable to know how sensitive to specific toxicants individual species are. For this, the SSD concept was introduced, to assess the fraction of species affected in a community. On the other hand, for most species no information about their toxicant sensitivity is available. To deal with this limitation the authors are grouping the available information (US-EPA, AQUIRE) so as to assign sensitivities to aquatic invertebrate taxa relative to Daphnia magna. This method enables the integration of various toxicants in the ranking of species, because a relative sensitivity compared to D. magna can be calculated for each species and toxicant. To ensure sufficient statistical power, related species are aggregated and taxa are ranked separately. With respect to organic compounds taxa of most of the aquatic invertebrate orders are considered. Some taxa of the Amphipoda, Plecoptera, and Cladocera (other than D. magna) are significantly more sensitive than D. magna. Hence, D. magna is among the most sensitive taxa. The use of these Relative Sensitivity Distributions as a predictive tool is shown and compared with the SSD concept. The use of the Relative Sensitivity values to link toxicant effects in mesocosm studies and field investigations is discussed.
Key words: Relative Sensitivity Distribution, Aquatic Invertebrates, Toxicity, Daphnia magna