甲基叔丁基醚无铅汽油遗传毒性研究

A study on genotoxicity of methyltertiary butyl ether unleaded gasoline

目的 研究甲基叔丁基醚 (MTBE)无铅汽油的遗传毒性 ,为保护接触人群的健康及制订卫生标准提供依据。方法 Ames试验使用TA97、TA98、TA10 0、TA10 2四个菌株 ,各菌株分别加S9与不加S9,MTBE无铅防爆汽油采用蒸气暴露法 ,设 2 5、 5 0、 10 0 μg/容器 ( 3L)三个浓度组 ,阴性和阳性对照采用平板掺入法 ;MTBE无铅汽油及纯汽油小鼠骨髓微核试验采用经呼吸道 4日染毒法 ,分别设 6864 0、 34 32 0、 2 2 88mg/m3和 10 8798、 5 7889、 362 7mg/m3三个浓度组 ,另设阴性对照组及环磷酰胺 5 0mg/kg腹腔注射为阳性对照组。结果 Ames试验中各菌株 (加与不加S9)回复突变菌落数均小于阴性对照组 2倍 ,呈阴性 ;MTBE无铅汽油及纯汽油小鼠骨髓微核试验 3个剂量组的微核率 ,与阴性对照组相比差异没有显著性 (P >0 0 5 )。结论 在本试验条件下 ,未发现MTBE无铅防爆汽油有致突变性和染色体损伤作用。

Objectives To study genotoxicity of methyltertiary butyl ether(MTBE)unleaded gasoline and to lay a basis for protecting their health of exposed workers and formulating hygienic standard of it.Methods Four strains of TA97,TA98,TA100 and TA102 with or without S9 added were used in Ames test.Bacteria strains were exposed to evaporating gas of MTBE unleaded gasoline at various doses of 25,50 and 100μg in a container with volume of three liters.Plate mixing method was used for positive and negative controls.Micronucleus assay of bone marrow was used for mice exposed to MTBE unleaded gasoline and pure gasoline via respiratory tract for four days,with positive controls treated by intraperitoneal injection of cyclophosphamide and negative controls.Results Number of bacteria colony of reverse mutation in various strains with or without S9 was less than that in negative controls,showing a negative Ames test.There was no significant difference in micronucleus rate between groups treated with MTBE unleaded gasoline and pure gasoline and negative control group(P>0 05).Conclusions No mutagenicity and damage to chromosome caused by MTBE unleaded gasoline was found in this experiment.