Abstract: Objective To study the toxic effects and mechanism of 2,2',4,4'-tetrabromodiphenyl ethers(PBDE-47) on INS-1 cells.Methods INS-1 cells were exposed to PBDE-47 at concentrations of 1,3,and 6 μmol/L in vitro and dimethyl sulfoxide(DMSO) was used as solvent control.After 24 hours,the rate of cellular survival,percentage of apoptosis,intracellular reactive oxygen species(ROS) level,malondialdehyde(MDA) content,and expression levels of cytochrome C and Fas genes were determined.Results Compared with the control group,both the rate of cellular survival in 3 μmol/L PBDE-47 treatment group (77.1±5.9%) and 6 μmol/L PBDE-47 treatment group(27.5±10.6%) were decreased significantly(P<0.05).The ROS levels in 3 μmol/L and 6 μmol/L PBDE-47 treatment groups were 154.1±13.3 and 220.1±1.1;MDA content in 3 μmol/L and 6 μmol/L PBDE-47 treatment groups were 26.1±1.0 μmol/L and 32.7±2.5 μmol/L,respectively,and the percentage of apoptosis in 6 μmol/L PBDE-47 treatment group was 38.4±4.2%,all of them were higher than those in the control group(P<0.05 for all).The expression levels of the cytochrome C and Fas genes were significantly increased with the increment of PBDE-47 concentration(P<0.05).Conclusion PBDE-47 may induce apoptosis of INS-1 cells and oxidized stress and the mitochondria signal passage may play an important role in the apoptosis induced by PBDE-47.