3-chloropropyltrimethoxysilane

Endpoint summary

Description of key information

Abiotic degradation:

(3-Chloropropyl)trimethoxysilane hydrolyses rapidly (<0.083 h at pH 4, 3.1 h at pH 7 and <0.1 h at pH 9 and 25°C) under relevant environmental conditions to form (3-chloropropyl)silanetriol and methanol. Reactions with water vapour rather than photolysis is likely to be the primary degradation process in air.

Biotic degradation:

A reliable ready biodegradation test is available, which indicates that no significant biodegradation in water of the hydrolysis product, (3-chloropropyl)silanetriol, is expected. The chemical safety assessment indicates that it is not necessary to obtain further information on biodegradation via simulation tests in water, sediment or soil.

Additional information

Table: Degradation rates

Degradation rate in water:	Hydrolysis half-life: 3.1 hours at pH 7 and 25°C, for removal of parent. No significant biodegradation of silanol hydrolysis product, (3-chloropropyl)silanetriol is expected.
Degradation rate in sediment:	No significant biodegradation of silanol hydrolysis product, (3-chloropropyl)silanetriol is expected.
Degradation rate in soil:	No significant biodegradation of silanol hydrolysis product, (3-chloropropyl)silanetriol is expected.
Degradation rate in air:	Half-life for reaction with hydroxyl radicals in air: 3.5 days for parent; 1.3 days for silanol hydrolysis product (predicted).