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Administrative data

Key value for chemical safety assessment

Additional information

Information is available from reliable studies for all the required in vitro endpoints. There were reliable positive and negative bacterial mutagenicity results: the negative study was selected as key, as it was obtained in a more recent study to the current guideline, and used test substance with a higher degree of purity. In addition, tests in mammalian cells gave negative results.


Short description of key information:
In vitro:
Gene mutation (Bacterial reverse mutation assay / Ames test): negative with and without activation (OECD TG 471)
Cytogenicity in mammalian cells: negative in CHO cells (OECD TG 473)
Mutagenicity in mammalian cells: negative in CHO-K1 cells (OECD TG 476)

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

The available information for the substance indicates that Tetramethylsilane (CAS 75 -76 -3) does not induces mutations in bacteria, as the positive result observed in one strain was not observed when test substance with a higher degree of purity was used in a more recent study. In addition, no potential for genetic toxicity was observed when Tetramethylsilane was tested in mammalian cells: no evidence of mutagenicity or cytogenicity was seen in mutagenicity and cytogenicity studies. In vivo testing is not considered necessary as the in vitro result are negative overall. It is concluded that classification for mutagenicity is not required.