Abstract

Purpose of this study was the validation of several effect assessment extrapolation procedures with toxicity data derived from experiments in more complex aquatic systems. A second goal was the comparison of the results of multiple species-experiments with toxicity data of single species-experiments for related species. With restrictions, due to paucity of data, it is concluded that single species toxicity data are a good starting point for establishing 'safe' concentrations for the aquatic ecosystem. Furthermore extrapolation procedures seem to be a good basis for establishing these 'safe' concentrations if sufficient toxicity data are available for sensitive taxonomic groups. From the results of this study it was not possible to prefer one of the validated extrapolation procedures.