Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

3 -Chloropropyl(dimethoxy)methylsilane hydrolyses rapidly to 3-chloropropyl(methyl)silanediol and methanol. Methanol is readily biodegrable. 3-Chloropropyl(methyl)silanediol is not expected to undergo any significant biodegradation, and is predicted to have low Henry’s Law constant and low log Kow/log Koc. Distribution modelling for STP indicates that water is the main compartment to which it is expected to partition in a sewage treatment plant. Water is also likely to be the main compartment to which 3-chloropropyl(methyl)silanediol will partition in the wider environment.

Additional information

Table: Degradation rates

Degradation rate in water:

Hydrolysis half-life: 1.3 hours at pH 7 and 20-25°C, for removal of parent (predicted). No significant biodegradation of silanol hydrolysis product expected.

Degradation rate in sediment:

No significant biodegradation of silanol hydrolysis product expected.

Degradation rate in soil:

No significant biodegradation of silanol hydrolysis product expected.

Degradation rate in air:

Half-life for reaction with hydroxyl radicals in air: 4.1 days for parent; 1.8 days for silanol hydrolysis product (predicted).