OECD 209: Activated sludge, respiration inhibition test (carbon and ammonium oxidation)
The Activated Sludge, Respiration Inhibition Test (carbon and ammonium oxidation) examines the effect of a given substance on the respiration rate of micro-organisms present in activated wastewater sludge.
Synthetic sewage mixtures are incubated at 20°C, and oxygen concentrations are measured to determine micro-organism respiration rates. This test can be used to determine the ECx and NOEC values of the test substance and support further tests for biodegradability.
This is a standard aquatic ecotoxicology study.