中文摘要：

目的采用体外实验评价溴系阻燃剂六溴环十二烷（HBCDs）对人乳腺（HBL-100）细胞的毒性，并探索其可能的致毒机制。方法将HBL-100细胞暴露于0（对照）、5、10、20、50、100mg／L的HBCDs。暴露2h后，检测上清液活性氧（ROS）含量；暴露24h后，检测细胞相对增殖率、胞内及上清液乳酸脱氢酶（LDH）活力和上清液中丙二醛（MDA）含量。结果与对照组比较，仅50—100mg／LHBCDs暴露HBL-100细胞的增殖率明显较低，差异均有统计学意义（P〈0．05）；其他浓度组HBL-100细胞的增殖率变化不显著。各浓度HBCDs暴露组HBL～100细胞内LDH的漏出率均较高，5-50mg／LHBCDs暴露组HBL-100细胞上清液中MDA和ROS的含量也较高，差异均有统计学意义（P〈0．05，P〈0．01）；且随着HBCDs暴露浓度的升高，HBL-100细胞内LDH的漏出率呈升高趋势，上清液中MDA和ROS的含量均呈先增加后减少的趋势。结论较高浓度HBCDs具有细胞毒性；低浓度HBCDs导致细胞氧化损伤，而高浓度HBCDs破坏细胞防御系统，导致细胞直接死亡。

英文摘要：

Objective To evaluate the cytotoxicity of brominated flame retardants hexabromocyclododecanes （HBCDs） in vitro experiments and reveal the eytoxic mechanism of HBCDs. Methods MTT assay was applied to study the inhibition rate of nonnal human breast cells （HBL-100）,which were exposed to the HBCDs with concentrations of O（eontrol）,5,10,20,50 and 100 mg/L respectively. ROS content in supernatant of each dose was measured with detection kit 2 hours later; After 24 hours of exposure, LDH activity of intraeellular and extraceflular fluid, MDA content in supernatant of each dose were measured with detection kits, respectively. Results Compared with the control, the inhibition rate of HBL-IO0 exposed to 50-100 mg/L HBCDs were significantly higher （P〈0.05）, low concentrations of HBCDs （5-20 mg/L） made no significant differences on the inhibition rate of HBL-100. Compared with the control, the increase of LDH leakage rate of each dose, MDA and ROS contents in supernatant of 5-50 mg/L HBCDs groups were much significant （P〈0.05,P〈0.01） with the increase of HBCDs,the LDH leakage rate of HBL-100 was increased and the content of MDA and ROS were increased first and decreased later. Conclusion According to the preliminary analysis,HBCDs is cytotoxie in a certain range of concentration. HBCDs with higher level can damage the protective system of ceils, arid lead them to death. Key words： Hexabromocyclododecanes; Human breast cells; Lactate dehydrogenase ; Malondialdehyde ; Reactive oxygen species