Abstract

This report ties down the method of ecotoxicological effect assessment followed by the RIVM. It describes an initial and refined method to determine maximum tolerable concentrations (MTCs) of chemical substances in water, sediment, soil, groundwater and air. Checks are included to prevent predators from secondary poisoning and ecological functioning from detoriation by harming microbiological processes. No attention is paid to factors that may play a role in deriving environmental standards from MTCs. The report als presents recommendations for future research and decision-making activities.