Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

No biodegradation observed, >240h, aerobic, BOD, activated sludge (Urano)

No biodegradation observed, 5d, aerobic, BOD5, sewage (Takemoto, see literature search)

7%, 28d, OECD 301C, aerobic, GC, activated sludge (CITI, see literature search)

Key value for chemical safety assessment

Biodegradation in water:
under test conditions no biodegradation observed

Additional information

The available experimental study (Urano, 1985) has several short-comings which leave the stand-alone result inconclusive. Aliphatic ethers have been identified as being potentially persistent chemicals, not prone to ready biodegradation (Toxtree, 2009). The combination of the two results are considered to be adequate for the prediction of not readily biodegradable and are considered to meet the information requirements of Annex VII, 9.2.1.1.

The following studies were retrieved from databases, but not included in the technical dossier (see literature search, Appendix B). Takemoto (1981) observed no biodegradation, but incubation period was only 5 days; the original study is not available. Likewise, the CITI (1992) study was unavailable, but the following information could be retrieved: MITI-I/OECD 301C, improved for volatile substances, 28 days, 100ppm test conc., 30ppm sludge conc., degradation TOC 3%, degradation GC 7%, BOD not calculated because the substance reacts with soda lime: non biodegradable.

Published literature indicates certain strains of bacteria, isolated and enriched from adapted sludge, are capable of cleaving ether bonds (Kim, 2004/2008), (Bacterial scission of ether bonds. White, G.F. et al, Microbiol. Rev., 60, 216 - 232). This is not incompatible with the small amount of degradation observed at the full 28d point by the CITI study.

Literature studies under non-guideline conditions indicate no anaerobic degradation of the substance.

Based on the weight-of-evidence, and in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.2, the available information is considered to be adequate for the purposes of risk assessment and classification and labelling.