Registration Dossier

Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Based on the degradation parameters determined, o-toluidine was classified as biodegradable under the given conditions. 

Key value for chemical safety assessment

Additional information

Biodegradation in river water was investigated in a simulation experiment. Test filter experiments were carried out by circulating water through a glass column filled with pumice. The experiments were carried out in darkness at a temperature of 208C under stable aerobic conditions. Compared to common batch tests the advantages of testfilter experiments are their short duration and the use of a population of microorganisms adapted to the river or wastewater. These simulate the biological degradation process which occurs in the river bed sediments under aerobic conditions.

Based on the degradation parameters determined, o-toluidine was classified as "very good" biodegradable under the given conditions.

Further, in mineral salts medium containing (NH4)2SO4, complete removal of otoluidine (400 mg/l) was achieved after 2 days of incubation. Using a mineral salts medium without (NH4)2SO4, o-toluidine served as sole source of carbon, nitrogen and energy and was completely degraded after 4 days. A Gram-positive bacterium (Rhodococcus rhodochrous) with the ability to utilize o-toluidine as sole source of carbon and nitrogen was isolated from soil.