Registration Dossier

Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

In vitro bacterial mutagenicity: the substance 2,2,4,4,6,6-hexamethylcyclotrisilazane was negative with and without a metabolic activation system in S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 (OECD TG 471) (Harlan, 2015).

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (negative)

Additional information

Hexamethylcyclotrisilazane has been tested for mutagenicity to bacteria, in a study which was conducted according to the OECD Technical Guideline 471, compliant with GLP (Harlan, 2015). No evidence of a test-substance related increase in the number of revertants was observed with or without metabolic activation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 in the initial plate incorporation study or the repeat experiment using the pre-incubation method, when tested up to limit concentrations. Appropriate positive, solvent and negative controls were included and gave the expected results. It is concluded that the test substance is negative for mutagenicity to bacteria under the conditions of the test.

Justification for classification or non-classification

Based on the available data for 2,2,4,4,6,6-hexamethylcyclotrisilazane, no classification is required for genetic toxicity according to Regulation (EC) No. 1272/2008.