Evaluation of the cytotoxicity and genotoxicity of the spermicides nonoxynol-9 and octoxynol-9.

The cytotoxic and genotoxic potentials of the spermicidal agents, nonoxynol-9 (N-9) and octoxynol-9 (0-9), were evaluated in in vitro test systems using rat liver cells. N-9 was also tested for the induction of sperm abnormalities in mice. Dose-related cytocidal effects were seen after the addition of N-9 and O-9 to the culture medium for 24 h. The mean concentrations of N-9 and O-9 necessary to decrease the number of viable cells by 50% (LC50) were 24 and 43 micrograms/ml of media, respectively. The spermicides neither induced DNA repair in freshly isolated hepatocytes, nor caused any mutations at HGPRT locus in the T51B rat liver cell line. There was also a lack of malignant transformation response in the low-calcium assay. Further, the germinal cells of mice remained unaffected by N-9.