Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Biodegradation of the test substance, based on DOC removal, averaged 97% after 28 days. The study report concludes the substance is inherently biodegradable

Key value for chemical safety assessment

Biodegradation in water:
inherently biodegradable, not fulfilling specific criteria

Additional information

A reliable measured biodegradation study for HQEE is available and included in the dossier.

 

Boeri and Ward (2003) conducted a reliable (Klimisch 1) GLP compliant study according to OECD 301 B (CO2 evolution) methods. The biodegradability of HQEE exposed to microorganisms derived from unacclimated activated sludge obtained from a municipal wastewater treatment plant was investigated under aerobic static exposure conditions. After 28 days the test substance showed 9% degradation, based on measured CO2. The study concluded that HQEE can not be considered to be readily biodegradable.

 

Lawrence and Ruffing (1995) conducted a reliable (Klimisch 1) GLP compliant study according to OECD 302 B methods. The inherent biodegradability of HQEE exposed to microorganisms derived from microoganisms from mixed liquor of suspended solids (sludge) obtained from a municipal wastewater treatment plant was investigated under aerobic static exposure conditions. DOC concentrations were measured on days 0, 1, 4, 6, 8, 11, 15, 18, 22, 25, 27, and 28 for loss. During the test, the positive control yielded DOC removals of >70% within 14 days, fulfilling test validity requirements. However, the level of 70% mineralization (DOC removal) was not reached within 7 days for the test substance. Biodegradation of the test substance, based on DOC removal, averaged 97% after 28 days. The study report concludes the substance is inherently biodegradable.