Cytogenetic toxicity of uranyl nitrate in Chinese hamster ovary cells

The effects of uranyl nitrate (UO2+2) on viability, cell cycle kinetics (CCK), micronuclei (MN), chromosome aberrations (CA), and sister-chromatid exchanges (SCE) in Chinese hamster ovary (CHO) cells were investigated. Uranyl nitrate decreased the viability of CHO cells in a dose-related fashion. The concentration for 50% inhibition (IC50) of uranyl nitrate on viability was 0.049 mM. Uranyl nitrate at concentrations ranging from 0.01 to 0.3 mM decreased CCK and increased frequencies of MN and SCE. CA were also significantly augmented by uranyl nitrate. This finding indicates that uranyl nitrate has the property of causing genotoxicity and cytotoxicity in CHO cells. It appears that this cytogenetic toxicity of uranyl nitrate provides a biological basis for the potential teratogenic effect of uranium on developing fetal mice.