DEHP is classified as readily biodegradable. Even if according to some experimental data the default figure assumed for mineralisation in sewage treatment plants must be taken with care, high removal rates (>90%) are confirmed by experimental data in STPs. It is the opinion of the CSTEE that there is a need for risk reduction measures for sediment dwelling organisms because the chemical is relatively persistent in aerobic soil and sediments and very persistent in anaerobic conditions. From the high number of short and long term experiments reported for fish and Daphnia, CSTEE says that it is reasonable to conclude that neither acute nor chronic effects were observed on aquatic organisms at the solubility level, even if a precise NOEC cannot be estimated.