Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 237-041-0 | CAS number: 13596-23-1
Short-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
Description of key information
There are no test data for the substance. However, read across data for related substances gives the following results: a 48-hour EC50 of >100 mg/L and a NOEC of ≥100 mg/L have been determined for the effects of related substance, trimethoxysilane (CAS 2487-90-3), on mobility of Daphnia magna. It is likely that the test organisms were exposed to the hydrolysis products of the substance. A 48-hour EC50 value of >844 mg/L and NOEC of ≥844 mg/L have been determined for the effects of tetraethyl orthosilicate (CAS 78-10-4) on mobility of Daphnia magna. Under the static exposure conditions used in the test it is likely that the test organism will have been primarily exposed to hydrolysis products of the test substance.
Key value for chemical safety assessment
Additional information
No test data for short-term toxicity to aquatic invertebrates are available for octachlorotrisilane.
However, studies of short-term toxicity to fish are available for the related substances trimethoxysilane and tetraethyl orthosilicate.
Octahlorotrisilane (CAS 13596-23-1) and trimethoxysilane (CAS 2487-90-3) hydrolyse to octahydroxytrisilane and silanetriol respectively and then both to monosilicic acid. The hydrolysis half-lives of octachlorotrisilane and trimethoxysilane indicate that, under conditions relevant to ecotoxicity assessment, both will hydrolyse to the same silicon hydrolysis products over the course of the test. The other hydrolysis products are hydrogen chloride and methanol, respectively; the properties of these substances are well characterised. Methanol is non-toxic to the environment and it is considered unlikely that its presence significantly affected the results of the test performed with trimethoxysilane. Effects of hydrogen chloride on aquatic organisms are limited to those that result from changes to pH in unbuffered media.
Tetraethyl orthosilicate (CAS 78-10-4) hydrolyses very rapidly to monosilicic acid and ethanol. Ethanol is non-toxic to the environment and it is considered unlikely that its presence significantly affected the results of the test performed with tetraethyl orthosilicate.
Monosilicic acid is a naturally occurring substance that is not harmful to aquatic organisms at relevant concentrations (Reference PFA 2013x).
References:
PFA, 2013x, Peter Fisk Associates, Analogue report - Ecotoxicity of (poly)silicic acid generating compounds, PFA.300.003.001
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
