Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

The substance was not mutagenic in the bacterial gene mutation test (Ames test).

In the in vitro chromosomal aberration test with mammalian cells, some positive effects were observed outside the historical control data range (low number of exchange figures), even though the total number of cells with chromosome aberrations was within the historical control data range. This test was finally considered to be positive.

Before further genotoxicity tests could be considered in order to fulfil the requirements under REACH, another authority outside Europe requested further investigation of genotoxicity. The request was refering to the clarification of chromosomal aberrations induced by this substance in vivo. It was agreed that this request can be covered by the micronucleus assay in mice. This in vivo assay did not confirm the positive findings observed in vitro in mammalian cells. The substance was considered to be non-mutagenic with respect to clastogenicity and/or aneugenicity in the mammalian erythrocyte micronucleus test.

The overall evidence from presently available data indicates that nitrososilane was not genotoxic in the respective assays.


Justification for selection of genetic toxicity endpoint
Regarding the overall data available for this substance, it is concluded that the substance is not genotoxic. No mutagenicity was observed in the bacterial gene mutation assay, and no induction of micronuclei was observed in the mammalian micronucleus test of murine peripheral blood cells (in vivo), which is ranked higher than the chromosomal aberration assay in mammalian cells (resulting in a positive response).

Short description of key information:
- REACH_negative | S. typhimurium TA 98, TA 100, TA 1535, TA 1537 and E. coli WP2 uvr | OECD 471 | with and without | [SPEC][/SPEC][SYN]Nitrososilane[/SYN][AM][/AM]#key study#
- REACH_positive│human lymphocytes | OECD 473 | with and without | [SPEC][/SPEC][SYN]Nitrososilane[/SYN][AM][/AM] #key study#
- REACH_negative | mouse (male/female) | OECD 474 (Micronucleus test) | [SPEC][/SPEC][SYN]Nitrososilane[/SYN][AM][/AM] #key study#

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

The substance is not classified for genetic toxicity because the overall evidence from available data indicates that nitrososilane is not genotoxic.