NRA studies toxicity-based discharge consents

Toxicity-based consents or direct toxicity assessment (DTA) have been used by the US Environment Protection Agency since the mid-1980s for consenting toxic effluents. In 1990, an NRA report on its future discharge consent policy proposed that DTA should be introduced in Britain for complex effluents where not all the constituents can be monitored and individually consented.

DTA involves testing effluents for toxicity on indicator aquatic