evaluation of genotoxicity of yukmijihwangtang a herbal formula yukmijihwangtang liu wei di huang tang rokumigan ymj has been used for body enrichment however little toxicological evaluation of ymj has been performed to assure its safety for clinical treatment to increase the safety information for ymj its genotoxicity was evaluated there was no increase in the number of revertant colonies in four strains of salmonella typhimurium or one strain of escherichia coli at any concentration of ymj studied regardless of the including when dosed with ymj metabolized with and s9 microsomal fraction ymj significantly increased structural aberrations in chinese hamster lung chl cells at the high concentrations 2500 and 5000 gml in the presence or absence of metabolic activation by the s9 microsomal fraction oral administration of ymj at doses up to 2000 mgkg did not increase the incidence of micronucleated polychromatic erythrocytes in bone marrow these results suggest that ymj is not genotoxic at the proper dose