Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Not readily biodegradable: 24% (CO2 evolution) in 28 days (OECD 301B)

Key value for chemical safety assessment

Additional information

One study investigating the ready biodegradability of Glycerides, C8-18 and C18-unsatd. mono- and di-, acetates (CAS No. 91052 -13 -0) is available (Clarke, 2009). The GLP study is conducted over 28 days according to OECD guideline 301B (CO2 evolution test) using activated sludge from a treatment plant treating predominantly domestic sewage. The test substance concentration tested was 10 mg/L carbon content (15.1 mg test substance/L). After 28 days 24% were biodegraded. Thus, Glycerides, C8-18 and C18-unsatd. mono- and di-, acetates was not readily biodegradable under the chosen test conditions.

Nevertheless, the components of Glycerides, C8-18 and C18-unsatd. mono- and di-, acetates are aliphatic fatty acids esters with glycerol. There are adequate biodegradability data in the scientific literature which support the premise that free fatty acids, would be expected to be rapidly and extensively biodegraded in aerobic systems in the environment (e.g. Swisher, 1987). Also for fatty acid salts with chain lengths up to and including C18 it is reported a complete metabolism under aerobic conditions, so that this substances can be considered to be readily biodegradable (HERA, 2003). Consequently, it can be assumed that the components of Glycerides, C8-18 and C18-unsatd. mono- and di-, acetates should be biodegraded faster than shown in the screening test mentioned above. This assumption is supported by two QSAR estimations which have been calculated for the two main fatty acid components of the described UVCB (C12 mono/diacetate and C14 mono/diacetate) using the program KOCWIN, v2.00 (Gebhardt 2013).

 

Swisher RD (1987). Surfactant Biodegradation, Marcel Dekker, New York. Biodegradability of fatty acids, pp. 826-827

HERA (2003). Fatty Acid Salts (Soap) Environmental Risk Assessment