OBJECTIVE: To investigate the effects of fluoride on lipid peroxidation, DNA damage and apoptosis in human embryo hepatocyte L-02 cells. METHODS: Lipid peroxide (LPO) level, reduced glutathione (GSH) content, DNA damage, apoptosis, and cell cycle analysis were measured after in vitro cultured L-02 cells were exposed to sodium fluoride at different doses (40 microg/mL, 80 microg/mL, and 160 microg/mL) for 24 hours. RESULTS: Fluoride caused an increase of LPO levels and a decrease of GSH content in L-02 cells. There appeared to be an obvious dose-effect relationship between the fluoride concentration and the observed changes. Fluoride also caused DNA damage and apoptosis and increased the cell number in S phase of cell cycle in the cells tested. There was a statistically significant difference in DNA damage and apoptosis when comparing the high dose of fluoride treated cells with the low dose of fluoride treated cells. CONCLUSION: Fluoride can cause lipid peroxidation, DNA damage, and apoptosis in the L-02 cell experimental model and there is a significant positive correlation between fluoride concentration and these pathological changes.