采用体外微核试验检测某电子烟液的遗传毒性

Genotoxicity evaluation of electronic cigarette liquid using the in vitro mammalian cell micronucleus test

目的:根据《OECD 487化学品测试方法 体外哺乳动物细胞微核试验》进行试验,检测某电子烟液诱发体外培养的哺乳动物细胞微核形成的能力,以评价其是否属于致突变物。方法:本研究的受试物终浓度分别为1.25、2.50和5.00μL/mL。同时设立溶剂对照组和阳性对照组。试验组和对照组均设2个平行样。在有代谢活化系统(+S9)和无代谢活化系统(-S9)条件下,使培养的中国仓鼠肺细胞(CHL)暴露于电子烟液中,分别染毒4和24 h,收获细胞,低渗固定,经吖啶橙染色后,于荧光显微镜下观察。每个剂量组选2 000个双核细胞进行分析,统计各组细胞微核率。结果:电子烟液在1.25、2.50和5.00μL/mL剂量下,无代谢活化系统短时处理组(4 h,-S9)细胞微核率分别为2.50‰、1.50‰及1.50‰,有代谢活化系统短时处理组(4 h,+S9)细胞微核率分别为1.50‰、2.00‰及1.00‰,无代谢活化系统连续处理组(24 h,-S9)细胞微核率分别为1.50‰、1.00‰及1.00‰,与溶剂对照组相比差异均无统计学意义(P>0.05)。结论:在本实验条件下,该电子烟液在1.25~5μL/mL浓度范围内,对CHL细胞无致突变作用。

OBJECTIVE:According to the OECD 487 Guidelines for testing of chemicals,the in vitro mammalian cell micronucleus test was used to determine whether the electronic cigarette liquid was mutagenic or not.METHODS:The doses for the liquid were 1.25,2.50 and 5.00μL/mL.Solvent and positive controls were included,and replicate cultures were set up per dose in the test.The CHL cells were exposed to the liquid in the presence or absence of an exogenous metabolic activation system(S9),for 4 and 24 hours of incubation.Then,they were harvested,exposed to hypotonic solution and fixed.The cells were then stained with acridine orange and observed under fluorescence microscopy.For each dose group,2000 binucleated cells were selected for micronucleus rate analysis.RESULTS:After incubation for 4 hours with the dose levels of 1.25,2.50 and 5.00μL/mL,the induced micronucleus rates without S9(4 h,-S9)were 2.50‰,1.50‰and 1.50‰respectively;and 1.50‰,2.00‰and 1.00‰respectively with S9(4 h,+S9).After 24 hours treatment without S9(24 h,-S9),the rates were 1.50‰,1.00‰and 1.00‰,respectively..Compared with the solvent control group,there was no statistically significant difference observed(P>0.05).CONCLUSION:Under the current test conditions,electronic cigarette liquid showed no evidence of mutagenic potential in the CHL at the tested dose level of 1.25-5 mg/mL.