Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

The behaviour of 2,4,6,8,10-pentamethylcyclopentasiloxane is dominated by hydrolysis (and condensation) reactions. On the basis of available data, the ultimate hydrolysis product relevant to the CAS is methylsilanetriol. This substance has very low volatility, low adsorption potential and is not expected to biodegrade. Therefore, any substance released to the environment is, under steady state conditions, expected to hydrolyse rapidly. At low concentrations, methylsilanetriol is expected to form and this is expected to be found in the aquatic compartment; it will degrade slowly via abiotic pathways. Over the long-term, further degradation in the environment, e.g. to silicate, is thought on grounds of chemical properties, to be possible.