2-Pentanone, 2,2',2''-[O,O',O''-(phenylsilylidyne)trioxime]

Biodegradation in water: screening tests

Description of key information

Based on the read-across approach from the analogue OS 1600 which attained 1% biodegradation within 28 days, OS9600 was considered not readily biodegradable. A ready biodegradation test was also performed on MPKO, the hydrolytic product of OS9600. It was also considered to be not readily biodegradable (4-12% degradation within 28 days).

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Key study: Read-across approach from experimental data on the analogue substance OS1600:

The ready biodegradability test was performed in accordance with OECD Guideline 301B and EU Method C4 -C using the carbon dioxide (CO2) evolution test (modified Strum test) (GLP study). Sewage was exposed to 12 mg TOC/L (43 mg/2 litres) of test substance under aerobic conditions for 28 days. The relative degradation values based on CO2 consumption calculated from the measurements performed during the test period revealed no significant degradation (1% biodegradation within 28 days). Based on these results OS9600 was designated as not readily biodegradable.

Supporting study: The ready biodegradability test was performed with the analogue substance MPKO in accordance with OECD Guideline 301B and EU Method C4 -C using the carbon dioxide (CO2) evolution test (modified Strum test) (GLP study). Sewage was exposed to 12 mg TOC/L (40 mg/2 litres) of MPKO under aerobic conditions for 28 days. The relative degradation values based on CO2 consumption calculated from the measurements performed during the test period revealed 4 and 12% degradation within 28 days. The study was considered to be valid. In conclusion, the test item was designated as not readily biodegradable.