Mutagenicity of various chemicals including nickel and cobalt compounds in cultured mouse FM3A cells

Employing a suspension culture of FM3A cells, we examined the cytotoxic and mutagenic effects of various chemical compounds. Mutagenicity of various types of mutagens (MNNG, ENNG, sterigmatocystin, mitomycin C, Trp-P-1, and X-rays) was sensitively detected by this assay. Mutagenicity of Trp-P-2 was detected in the presence of an activating enzyme system. Nickel(II) and cobalt(II) compounds (NiCl2, Ni(CH3COO)2, nickel complex [(C2H5)4N]2 [NiCl4], CoCl2, and a cobalt complex [(C2H5)4N]2-[CoCl4]) were cytotoxic to FM3A cells at concentrations of over 1 X 10(-4) M, and produced 2-6-fold increases of the control in the average number of 6-thioguanine-resistant (6TGr) colonies over a very narrow concentration range of 2-4 X 10(-4) M. Comparison of the mutagenicity of various chemical compounds suggested that some of the nickel(II) and cobalt(II) compounds were very weak mutagens.