Genotoxicity studies on selected organosilicon compounds: in vivo assays.

Six organosilicon compounds which had been found to have clastogenic activity in an in vitro battery of genotoxicity assays were evaluated in rat bone marrow cytogenetic assays for assessing clastogenicity in an in vivo system. None of the six compounds produced significant increases in chromosome aberrations in the rodent assay. However, trimethylsilanol produced a single value at the high-dose level/48-hr sampling interval that was significantly elevated when compared to the low concurrent control value. Both an independent repeat of the bone marrow cytogenetic assay and performance of the rat dominant lethal test failed to substantiate the presence of any significant clastogenic activity. Organosilicon compounds involved in the synthesis and degradation of polydimethylsiloxanes were not genotoxic in the in vivo clastogenicity tests employed in these studies.