Does over-exposure to copper ions released from metallic copper induce cytotoxic and genotoxic effects on mammalian cells?

BackgroundA high dissolution of copper from intrauterine devices (IUDs) occurs during the first days after insertion. This work is focused on the assessment of the possible cyto- and genotoxic effects of different concentrations of copper ions released from metallic copper on mammalian cells in vitro.Study DesignColorimetric tetrazolium/Trypan blue (TB) tests and Comet assay were used to evaluate potential cytotoxicity and genotoxicity, respectively, in Chinese hamster ovary cells (CHO-K1).ResultsReduction of mitochondrial activity by copper ions was observed for extracts at ≥7.42 mg/L concentrations, while TB exclusion test for plasma membrane integrity showed significant decrease in cell viability (close to 90%) for 10.85 mg/L concentration. Additionally, copper-induced DNA damage was detected for 5.67–7.42 mg/L concentration range.ConclusionOur results demonstrate cytotoxic and genotoxic effects of copper ions released from metallic copper on CHO-K1 cells and emphasize the importance of reducing the initial copper dissolution from IUD without affecting the contraceptive action.