What are Environmental Quality Standards?

Environmental Quality Standards (EQS's) are levels that are used to assess the risk of chemical pollutant effects on water quality to the health of aquatic plants and animals. The method for deriving EQSs? is set out in the WFD (Annex V)and involves the testing of the toxicity of the substance on aquatic biology.

The UK has existing EQSs? for many of these substances, although work is required to ensure their derivation is compliant with the WFD methodology. EQSs? for priority and priority hazardous substances will be set at a European level.