Registration Dossier

Diss Factsheets

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
adsorption / desorption: screening
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
the study does not need to be conducted because the physicochemical properties of the substance indicate that it can be expected to have a low potential for adsorption

Description of key information

Adsorption/desorption: Low potential for adsorption to organic carbon.

Key value for chemical safety assessment

Additional information

Testing is waived in accordance with Column 2 of REACH Annex IX. The substance has a low potential for adsorption.

The substance hydrolyses very rapidly in contact with water, generating HCl and silanetriol. Further hydrolysis of silanetriol is then expected to occur rapidly to monosilicic acid and hydrogen. Both silanetriol and monosilicic acid exist only in dilute aqueous solutions and readily condense at concentrations above approximately 100 -150 mg/L as SiO2 to give a dynamic equilibrium between monomer, oligomers and insoluble amorphous polysilicic acid. These hydrolysis products are inorganic substances which enter natural biogeochemical cycles; adsorption/desorption studies are not relevant. Based on their structure and predicted water solubilities, the hydrolysis products will have a high affinity for water and a low affinity for organic carbon and so a low potential for adsorption to the organic carbon. However, they may interact with the mineral content of soil. Amorphous polysilicic acid is a constituent of most soils.

Categories Display