AN ASSESSMENT OF THE GENETIC TOXICOLOGY OF ANTIMONY TRIOXIDE

Antimony trioxide (Sb2O3, CAS 1309-64-4) has been examined in a range of in vitro and in vivo genotoxicity assays. Negative results were obt ained with the Salmonella/microsome assay and the L5178Y mutation assa y, but a positive response was observed in the in vitro cytogenetic as say using isolated human peripheral lymphocytes. However, in vivo, ant imony trioxide was non-clastogenic in the mouse bone marrow micronucle us assay, following oral gavage administration for 1, 7, 14 or 21 days at dose levels of up to 5000 mg/kg (single dose) or 1000 mg/kg (repea t dose). A negative result was also obtained in the in vivo rat liver DNA repair (unscheduled DNA synthesis) assay following a single oral g avage administration of doses up to 5000 mg/kg. These data show no gen otoxicity for antimony trioxide in vivo and do not confirm a previous report of clastogenicity in the mouse on repeated dosing. It is conclu ded that antimony trioxide is not genotoxic in vivo and does not prese nt a genotoxic hazard to humans. (C) 1998 Elsevier Science B.V. All ri ghts reserved.