苯和甲醛对BALB/c小鼠的联合遗传毒性

Combined genotoxicity of benzene and formaldehyde co-exposure in BALB/c mice

目的:以苯和甲醛对BALB/c小鼠进行联合染毒,探讨苯和甲醛对BALB/c小鼠联合染毒可能导致的亚急性毒性和遗传毒性。方法:选用BALB/c小鼠,设苯组(50mg/kg,溶于玉米油)、甲醛组(2mg/kg,溶于生理盐水)、苯和甲醛联合染毒组(苯50mg/kg,甲醛2mg/kg)及溶剂对照组(玉米油和生理盐水对照组),各组给小鼠行腹腔注射受试物,每日1次,连续染毒30d后继续饲养30d。实验中定期监测观察小鼠一般情况、外周血血象、网织红细胞微核率和淋巴细胞彗星率,染毒结束后30d处死动物,行组织病理学检测和骨髓镜检。结果:苯_甲醛联合染毒组小鼠体质量降低,且染毒结束后,体质量持续降低,但与对照组比较差异无统计学意义;苯和苯_甲醛联合染毒组小鼠外周血红细胞数显著降低(P<0.05),染毒结束30d后血液学指标恢复正常。苯_甲醛联合染毒组小鼠染毒后外周血网织红细胞微核率和彗星率显著升高(P<0.05),两者具有协同作用,且染毒结束30d后仍高于对照组(P<0.05)。结论:苯和甲醛的亚急性联合染毒可致BABL/c小鼠外周血细胞的协同遗传毒性作用,此种作用具有持续性。

OBJECTIVE：To explore the subacute toxicity and genotoxicity of benzene and formaldehyde co-exposure in BALB/c mice.METHODS：BALB/c mice were exposed to benzene（50 mg/kg,dissolved in corn oil）,formaldehyde（2 mg/kg,dissolved in saline）and Solvent control group（corn oil and formaldehyde）.The mice of each group were treated with test materials by intraperitoneal injection,once per day,for 30 d.The mice were bred for another 30 d after treatment.During the experiment period,growth of the mice was observed.Meanwhile,following indices were evaluated：parameters of peripheral blood,micronucleus frequency in leucocytes and comet assay in leucocytes.RESULTS：The body weight decreased in benzene-formaldehyde co-exposure group and decreased continually after exposure without significant difference compared with control groups.The RBC was decreased significantly in benzene and co-exposure group（P〈0.05）,but the parameters of peripheral blood recovered 30 d after exposure.Benzene and formaldehyde exerted a synergistic effect on the significant increase of micronucleus frequency and DNA damage ratios（P〈0.05）.The effects lasted till 30 d and still higher than control groups after co-exposure.CONCLUSION：Subacute toxicity caused by co-exposure of benzene and formaldehyde in mice led to synergistic and persistant genotoxicity.