Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

One key study was available on the biodegradation of Trigonox 101.

This study was performed according to modified OECD Test Guidelines to permit prolonged measurements with no GLP statement.

In the SCAS test, Trigonox 101 was exposed to activated sludge maintained by daily addition of primary settled sewage for a period of 8 weeks. The test substance caused no reduction of the biodegradation of the organic compounds present in primary settled sewage. Therefore the test substance is considered to be non-inhibitory to the activated sludge. Trigonox 101 was not degraded in prolonged Closed Bottle tests inoculated with unacclimated and acclimated sludge from the SCAS unit. This result demonstrates that microorganisms do not have the ability to grow on this organic peroxide under aerobic conditions. Potential decomposition products of the test substance i.e. tert butanol and 2,5-dimethyl-2,5-hexanediol were degraded in Closed Bottle tests with both acclimated and unacclimated sludge (> 80% within 56 days).The length of the lag period found with 2,5-dimethyl-2,5-hexanediol with acclimated sludge was short compared to the period obtained with unacclimated sludge. This result suggests that the peroxide bond of Trigonox 101 is cleaved in the SCAS unit.