4种常见残留农药联合作用对小鼠遗传毒性研究

Combined genetic toxicity of four kinds of common residual pesticides in mice

目的利用小鼠骨髓嗜多染红细胞微核试验及小鼠精子畸形试验,研究马拉硫磷、毒死蜱、氯氰菊酯和高效氯氟氰菊酯4种常见残留农药在每日允许摄入剂量下单独与联合作用对小鼠遗传毒性的影响。方法将70只昆明种小鼠随机分为7组,每组10只,雌雄各半,分别为溶剂对照组,阳性对照组,马拉硫磷(0.3 mg/kg·BW)组,毒死蜱(0.01 mg/kg·BW)组,氯氰菊酯(0.02 mg/kg·BW)组,高效氯氟氰菊酯(0.02 mg/kg·BW)组及农药联合作用组。每天经口染毒1次,连续4天,于染毒结束次日进行小鼠骨髓嗜多染红细胞微核试验;同时,将35只雄性昆明种小鼠随机分为7组,每组5只,组别同上,每天经口染毒1次,连续5天,于首次染毒后第35天进行小鼠精子畸形试验。结果 4种农药单独作用时,小鼠骨髓细胞微核率及精子畸形率略高于溶剂对照组,差异无统计学意义(P>0.05);4种农药联合作用时,小鼠骨髓细胞微核率及精子畸形率升高,分别为17.30±2.83及5.84±1.05,显著高于单独作用组及溶剂对照组,差异有统计学意义(P<0.05)。结论马拉硫磷、毒死蜱、氯氰菊酯、高效氯氟氰菊酯单独与联合经口染毒均可致小鼠骨髓细胞微核率、精子畸形率增加,且联合染毒对小鼠的遗传损伤具有一定的相加作用,具有引起遗传毒性的风险。

[Objective]By using the micronucleus test ofbone marrow polychromatic erythrocytes and mouse sperm abnormality test,to study the individual and combined effects of malathion,chlorpyrifos,cypermethrin and lambda-cyhalothrin on genetic toxicity in mice.[Methods]According to the allowed daily intake（ADI）,70 Kunming mice were randomly divided into seven groups including solvent control group,positive control group,malathion（0.3 mg/kg·BW）,chlorpyrifos（0.01 mg/kg·BW）,cypermethrin（0.02 mg/kg·BW）,lambda-cyhalothrin（0.02 mg/kg·BW） and combined group,10 animals in each group（5 males and 5 females）,one dose level per group for a period of four days gavage. The micronucleus test ofbone marrow polychromatic erythrocytes was conducted at 24 h after the final treatment. At the same time,another 35 male Kunming mice were randomly divided into seven groups same as above,one dose level per group for a period of five days gavage. The mouse sperm abnormality test was conducted on the 35 th day after the first oral dosing.[Results]The micronucleus rate of bone-marrow cells and the aberration rate of sperm in the four individual effect groups were higher than that in solvent control group,but the differences had not statistically significant（P〈0.05）. The micronucleus rate of bone-marrow cells（17.30±2.83） and the aberration rate of sperm（5.84±1.05） in the combined effect group were higher than that in individual effect groups and the solvent control group,and the differences were statistically significant（P〈0.05）.[Conclusion]Both individual groups and combined group of malathion,chlorpyrifos,cypermethrin and lambda-cyhalothrin by gavage can cause significant increase in the micronucleus rate of bone-marrow cells and the aberration rate of sperm. The combined effect of these pesticides has additive effect on genetic damage in mice,with the risk of genotoxicity.