Activated Sludge Respiration Inhibition (OECD 209)

Activated Sludge Respiration Inhibition Test (ASRIT) - Carbon and/or Ammonium Oxidation

This test examines the effect of test substances on the activity of activated sludge microorganisms taken from a sewage works receiving largely domestic sewage. The test can be used to estimate possible effects on a sewage works and the results can be used to set a suitable concentration range for further biodegradation studies. The test substance is added at different concentrations to activated sludge and incubated at 21 ± 2°C under fully aerated conditions for 3 hours. The respiration rate is measured over a 10-minute period using Dissolved Oxygen probes and closed BOD bottles.


Assess the effects of your product on the activity of activated sludge microorganisms.

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