Trimethoxy(2,4,4-trimethylpentyl)silane

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study planned

Study period:

The test will be conducted after a decision on the requirement to carry out the proposed test has been taken. The lead registrant considers 18 months as appropriate for test performance of an OECD 210 and dossier update with results.

Justification for type of information:

TESTING PROPOSAL ON VERTEBRATE ANIMALS

NON-CONFIDENTIAL NAME OF SUBSTANCE:
- Name of the substance on which testing is proposed to be carried out : Testing will be done focussing on (2,4,4-trimethylpentyl)silanetriol, which is the silanol hydrolysis product of the registered compound trimethoxy(2,4,4-trimethylpentyl)silane (CAS No. 34396-03-7). For this purpose, trimethoxy(2,4,4-trimethylpentyl)silane (CAS No. 34396-03-7) will be pre-hydrolysed for test substance application. Because the hydrolysis half-life of the registered substance is < 12 h (DT50 = 5.7 h at pH 7 and 20-25 °C, QSAR), the appropriate assessment entity for the evaluation of environmental hazards and risks is the silanol hydrolysis product of the registered compound (REACH guidance R.16 (ECHA, 2016)). Methanol is known for its absence of environmental effects up to the concentrations that are relevant to the present aquatic studies (OECD SIDS, 2004) and therefore can be disregarded in the environmental hazard and risk assessment.

CONSIDERATIONS THAT THE GENERAL ADAPTATION POSSIBILITIES OF ANNEX XI OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION
- Available GLP studies : No studies on the long-term toxicity on fish are available for the registered compound, its hydrolysis product, or structurally similar substances
- Available non-GLP studies: No studies on the long-term toxicity on fish are available for the registered compound, its silanol hydrolysis product or structurally similar substances
- Historical human/control data
- (Q)SAR : No data is available
- In vitro methods : No data is available
- Weight of evidence : No data is available
- Grouping and read-across : No studies on the long-term toxicity on fish are available for the registered compound, its silanol hydrolysis product, or structurally similar substances
- Substance-tailored exposure driven testing [if applicable]: Not applicable
- Approaches in addition to above [if applicable]: Not applicable
- Other reasons [if applicable]: See below


CONSIDERATIONS THAT THE SPECIFIC ADAPTATION POSSIBILITIES OF ANNEXES VI TO X (AND COLUMN 2 THEREOF) OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION:
- The registered compound is produced in a tonnage of 100 - 1000 tonnes annually and thus long-term toxicity testing of fish is a data requirement according to Annex IX of the REACH regulation 1907/2006. Because no studies on the long-term toxicity towards fish are available for the registered compound, its silanol hydrolysis product, or structurally similar substances and the registered substance has a wide dispersive use, it is considered inappropriate to apply other non-testing strategies in order to fulfil the data requirement for this endpoint. Therefore, testing of chronic toxicity towards fish according to OECD guideline 210 is proposed for the silanol hydrolysis product of the registered compound.

Qualifier:

according to guideline

Guideline:

OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test)

Description of key information

A long-term toxicity study on fish according to OECD guideline 210 is beeing proposed, targeting the silanol hydrolysis product as the relevant entity for testing.