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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Abiotic degradation

3-(Triethoxysilyl)propanethiol has a measured hydrolysis half-life of 32.1 hours at 20°C and pH 7 (see CSR section 4.1.1.1 and IUCLID section 5.1.2) and a half-life of 0.3 days for reaction with hydroxyl radicals in air has been calculated for the substance.

The hydrolysis products are 3-(trihydroxyysilyl)propanethiol and ethanol.

 

Biotic degradation

A biodegradation rate of 51% in 28 days (DOC removal) has been read-across from an analogue substance, 3-(trimethoxysilyl)propane-1 -thiol. This biodegradation is attributed to the biodegradation of the methanol hydrolysis product, which is readily biodegradable (OECD 2004). No significant biodegradation is expected for the silanol hydrolysis product.

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: 32.1 hours at pH 7 and 20°C, for removal of parent. No significant biodegradation of silanol hydrolysis product is expected.

Degradation rate in sediment:

No significant biodegradation of silanol hydrolysis product is expected.

Degradation rate in soil:

No significant biodegradation of silanol hydrolysis product is expected.

Degradation rate in air:

Half-life for reaction with hydroxyl radicals in air: 0.3 days for parent; 0.3 days for silanol hydrolysis product (predicted).