Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

The distribution in a sewage treatment plant (STP) has been estimated using the SimpleTreat model (implemented in EUSES 2.1.2/Chesar 3.4), see table below. Due to the moderate hydrolysis of the registered substance, the distribution calculation is done for both the parent substance and the hydrolysis products, octylsilanetriol and ethanol.

Table: Distribution modelling for STP

 

Triethoxy(octyl)silane

Octylsilanetriol

Ethanol

 Unit

 Fraction of emission directed to water by STP

38.44

99.5

12.62

[%]

Fraction of emission directed to air by STP

9.966

1.89E-6

0.075

[%]

Fraction of emission directed to sludge by STP

51.58

0.498

0.069

[%]

Fraction of the emission degraded in STP

0

0

87.23

[%]

 

Triethoxy(octyl)silane is not expected to undergo any significant biodegradation and is predicted to have moderate Henry’s Law constant and high log Kow/log Koc. Therefore, water and sludge are the main compartments to which it is expected to partition in a sewage treatment plant, with partition to air also being significant.

Octylsilanetriol is predicted to have very low Henry's Law constant, low log Kow/log Koc. Therefore, water is the main compartment to which it is expected to partition in a sewage treatment plant.