The effects of sodium azide on mammalian cells cultivated in vitro

Sodium azide acted cytostatically to cytotoxically on 2 lines of mammalian cells. After application of the substance in an acid environment the highest cytostatic effect was noted. The results of the DNA-synthesis inhibition test suggest that sodium azide does not damage the DNA of the observed fibroblasts with any of the tested modes of application. In Chinese hamster cells neither 20-h treatment in medium nor 60-min treatment in an acid environment gave rise to significantly increased occurrence of 6-TG-resistant mutations. The results of the DNA-synthesis inhibition test, as well as the mutagenicity testing, do not suggest the possibility that treatment with sodium azide might induce DNA damage in the observed human and Chinese hamster cells. The cytostatic effect of sodium azide on the fibroblasts studied is probably not accompanied by a genotoxic effect.