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Environmental fate & pathways

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Additional information

The distribution in a sewage treatment plant (STP) has been estimated using the SimpleTreat model (implemented in EUSES 2.1.2/Chesar 3.1), see table below. Due to the rapid hydrolysis of 3-(trimethoxysilyl)propane-1-thiol, the distribution calculation is done for the silanol hydrolysis product, 3-(trihydroxysilyl)propanethiol.

Table: Distribution modelling for STP

Fraction of emission directed to air by STP

1.6E-08

[%]

Fraction of emission directed to water by STP

100

[%]

Fraction of emission directed to sludge by STP

0.025

[%]

Fraction of the emission degraded in STP

0

[%]

3 -Trimethoxysilylpropane-1-thiol hydrolyses rapidly to 3-(trihydroxysilyl)propanethiol and methanol. Methanol is readily biodegradable. 3-(Trihydroxysilyl)propanethiol is not expected to undergo any significant biodegradation, and is predicted to have very 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-(trihydroxysilyl)propanethiol will partition in the wider environment.