Exploring community-based environmental hazard assessments of mixtures based on MOA-based approaches

Background

There is an increasing awareness of the need to complement single substance assessments with the assessment of mixtures. Mode of action considerations have been proposed to derive environmental thresholds for substances with the same mode of action. This implies that for mixtures of substances which act according to the same mode of action, there is one threshold, i.e. a concentrations below which no impact on the environment is expected. Finally, there is an acknowledged need to increase ecological realism of environmental assessments by considering communities rather than single species to represent that represent whole communities. These three developments in the field of risk assessment in the aquatic environment are to be tied together in the work of the proposed task force. Its objective is to draft a provisional ecological risk assessment approach based on a review of the current state of science in the areas of mode of action, mixtures and community assessment. Second, the knowledge gaps for actual implementation the provisional assessment approach are to be identified.