Abstract
We tested nine (cadmium chloride, chloral hydrate, colchicine, diazepam, econazole nitrate, hydroquinone, pyrimethamine, thiabendazole, thimerosal) of the 10 known or suspected spindle poisons of the coordinated programme to study aneuploidy induction sponsored by the Commission of the European Communities using Saccharomyces cerevisiae D61.M (mitotic chromosomal malsegregation system). Mitotic malsegregation of chromosome VII was induced by chloral hydrate, thiabendazole and thimerosal. Diazepam, colchicine, cadmium chloride, econazole nitrate, hydroquinone and pyrimethamine revealed no induction of chromosomal malsegregation.