Superoxide anion generated by potassium superoxide is cytotoxic and mutagenic to chinese hamster ovary cells.

Chinese hamster ovary cells in vitro were exposed to superoxide anion (O2-) generated by the addition of potassium superoxide (KO2) to the cell culture media. It was determined that 2 nmoles O2- per ml media resulted in approximately 50% cell mortality. The number of 6-thioguanine-resistant mutants was also increased in a dose-related fashion. Both these effects of KO2 were inhibitable by the prior addition of superoxide dismutase, indicating that superoxide anion is cytotoxic and genotoxic in mammalian cells.