深圳和太原PM2.5样品致突变作用研究

目的：探讨深圳和太原大气细颗粒物（PM_2.5）样品是否具有致突变作用。方法：应用组氨酸缺陷型鼠伤寒沙门氏菌TA97、TA98、TA100、TA102和TA1535，通过平板渗入法同时对广东深圳和山西太原两地的PM_2.5样品进行标准Ames试验。实验设4个PM_2.5剂量组（分别为每皿40、100、200和400 μg）、1个阴性对照组和1个阳性对照组，每种细菌均设立加S9和不加S9两种试验组。结果：深圳PM_2.5样品的Ames试验结果显示，TA97、TA100和TA102在PM_2.5样品处理后菌落回变数显著高于阴性对照组，加S9与不加S9的菌落回变数比较差异有统计学意义（P < 0.01）。太原样品的Ames试验结果显示，TA97、TA98和TA100在PM_2.5样品处理后菌落回变数显著高于阴性对照组，加S9与不加S9的菌落回变数比较差异有统计学意义（P < 0.05或P < 0.01）。但深圳和太原PM_2.5样品对TA1535未见阳性结果，结论：深圳和太原PM_2.5样品均能够引起TA97、TA98、TA100的Ames试验的自发回变数阳性结果，表明深圳和太原PM_2.5样品均具有致基因突变作用。

Mutagenicity of PM2.5 samples from Shenzhen and Taiyuan

OBJECTIVE: The Ames tests were used to investigate the mutagenicity of PM_2.5 samples which were collected from Shenzhen and Taiyuan. METHODS: The histidine-deficient Salmonella typhimurium strains TA97,TA98,TA100,TA102 and TA1535 were used. From the collected samples,four doses of PM_2.5 (40,100,200,and 400 μg per dish),a negative control and a positive control were tested. Each test group was treated with S9 or without S9. RESULTS: After treatment with PM_2.5 samples from Shenzhen,there were significant differences in mutagenicity (P < 0.01) between +S9 and -S9 groups in TA98,TA100 and TA102.Similar results were observed with PM_2.5 samples from Taiyuan in TA97,TA98 and TA100. These results indicated that the PM_2.5 samples from Shenzhen and Taiyuan contained mutagenic chemicals which did not cause mutation in TA1535. CONCLUSION: Overall,our results indicate that PM_2.5 samples from Shenzhen and Taiyuan contained directly and indirectly acting mutagens.