Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The percentage biodegradation of TOFA_TETA_PAA_BADGE_CGE_Adduct reached a maximum of 9% over the course of the 28 day incubation and therefore failed to meet the requirements for ready biodegradability.

Key value for chemical safety assessment

Biodegradation in water:
under test conditions no biodegradation observed

Additional information

The ready biodegradability of TOFA_TETA_PAA_BADGE_CGE_Adduct was assessed by measurement of the amount of dissolved oxygen consumed during mineralisation of the test substance in completely filled, sealed bottles under standard conditions. The procedure followed was that described in OECD Guideline 301D, Closed Bottle Test (adopted July 1992).

In order for the test substance to be defined as 'readily' biodegradable, the percentage biodegradation must amount to at least 60% of ThOD, both within the 28-day incubation period and within 10 days of first reaching 10% biodegradation.The percentage biodegradation of TOFA_TETA_PAA_BADGE_CGE_Adduct at Day 28 was 9%. Therefore, TOFA_TETA_PAA_BADGE_CGE_Adduct cannot be considered to be readily biodegradable.

Biodegradation of the reference substance, sodium benzoate, was 76% on Day 14 and 73% at the end of the test. These data show that the inoculum was viable and exerted normal degradative activity. The calculated percent biodegradation at Day 28 may be slightly lower than that at Day 14 due to an increase in the blank control oxygen demand relative to that in the reference substance samples. In the toxicity control group, biodegradation of sodium benzoate was slightly lower at 68% on Day 14 and Day 28, suggesting that the test substance was exerting a small inhibitory effect on the microbial degradation of the reference substance.

All validity criteria were satisfied and the results of this study are therefore considered to be valid.