The forward mutational assay on Schizosaccharomyces pombe and the mitotic gene conversion assay on Saccharomyces cerevisiae were performed in order to verify whether alpha-(2,4-dichlorophenyl)-beta,N-imidazolylethyl 4-phenylthiobenzyl ether nitrate (fenticonazole, Rec 15/1476) shows a potential mutagenicity. In both tests the drug does not seem to possess any mutagenic activity when compared with mutagenic standards.