[Comparative study on the mutagenicity of the gasoline-fueled vehicle exhaust and methanol-fueled vehicle exhaust].

OBJECTIVE: In order to compare the mutagenicity of the gasoline-fueled vehicle exhaust (gasoline exhaust for short) and the methanol-fueled vehicle exhaust (methanol exhaust for short), provide a scientific basis for replacement gasoline by methanol as fuel in vehicle. METHODS: The Ames assay and A549 cell micronucleus test in vitro were applied to compare the mutagenicity of gasoline-fueled vehicle exhaust and methanol-fueled vehicle exhaust. RESULTS: The results showed that the gasoline-fueled vehicle exhaust expressed evident mutagenicity in Ames assay (TA98 strain) with or without rat liver-derived metabolic activation system (S9). The mutagenicity increased obviously when S9 was used and showed a good dose-response relationship. However, the methanol-fueled vehicle exhaust did not show any mutagenic potential in Ames assay (TA98, TA100 strains) with or without rat liver-derived metabolic activation system (S9). In A549 cells micronucleus test in vitro, between 0.025 - 0.2JL/ml, the rate of A549 cells micronucleus could be induced by the gasoline-fueled vehicle exhaust. For the methanol-fueled vehicle exhaust, there was no significant differences in the rate of A549 cells micronucleus between the tested groups and control. CONCLUSION: The results strongly suggested that the gasoline-fueled vehicle exhaust had potential mutagenicity and the methanol-fueled vehicle exhaust did not show any potential mutagenicity. The results also provided a scientific basis for replacement gasoline by methanol as fuel in vehicle.

[Genotoxicity comparison between gasoline- and methanol-fueled exhaust by TK gene mutation assay].

Methanol fuel is a most promising substitute for gasoline. It is scarcely reported about methanol-fueled exhaust on the health effect, neither about genotoxicity research between methanol- and gasoline-fueled exhaust. In the present study, the two kinds of exhaust were sampled directly from tailpipe at the same type bus, the same state, L5178Y thymidine kinase (TK) gene mutation assay was used to investigate their genotoxicity at the same dose range, and compared with micronucleus and comet assay. The results showed that the genotoxicity of gasoline-fueled exhaust is stronger than that of methanol-fueled exhaust, while the cytotoxicity of methanol-fueled exhaust is stronger than that of gasoline-fueled exhaust at dose range. The study demonstrated that L5178Y TK gene mutation assay is more sensitive than micronucleus and comet assay.