用SOS/umu测试评价光电催化降解五氯酚过程的遗传毒性特征

Genotoxic Characterization of PCP Solution during Its Photoelectrocatalysis Process with SOS/umu Assay

采用SOS/umu测试研究了五氯酚水溶液在光电催化反应过程中的遗传毒性变化及降解产物对鼠伤寒沙门氏菌TA1535/pSK1002的细胞毒性,并与五氯酚在直接光解、光催化反应过程中的降解产物进行了比较.五氯酚光电催化降解过程中降解产物对测试菌种的细胞毒性逐渐降低,产物经代谢活化的细胞毒性低于直接光解、光催化降解五氯酚的产物.五氯酚经光电催化降解15￣45分钟的产物经代谢活化测试结果呈阳性,在60￣120分钟的降解产物呈阴性,说明五氯酚的光电催化降解过程中生成了间接遗传毒性物质,但该类物质能够在光电催化过程中被去除.而五氯酚经直接光解、光催化处理120分钟的产物均具有遗传毒性风险.本研究结果表明光电催化技术的环境安全性优于直接光解、光催化技术.此外,SOS/umu测试作为一种简单、灵敏的遗传毒性物质检测方法,适合于评价光电催化技术的遗传毒性特征,可以作为评价该技术环境安全性的生态毒理学方法之一.

SOS/umu assay employing Salmonella typhimurium TA1535/pSK1002 was conducted to evaluate the genotoxic and cytotoxic characteristics of PCP solution during its photoeletrocatalysis process. As a comparison ,the direct photolysis and photocatalysis process were also studied. During the photoelectrocatalytic process of PCP under given conditions,the cytotoxicity of the reaction products decreased steadily. The reaction products of photoelectrocatalysis were less cytotoxic than that of direct photolysis and photocatalysis after metabolic activation. The samples photoelectrocatalized for 15 -45min caused genotoxic responses with the addition of S9-enzyme fraction. The samples photoelectrocatalized for more than 60min showed no genotoxic potency, indicating the indirect genotoxic intermediates formed could be removed in this process. For the photolytic and photocatalytic process,the samples irradiated for 120min still exhibited genotoxicity. These results suggested that photoelectrocatalysis exhibited its priority over the direct photolysis and photocatalysis considering their environmental safety. Moreover, SOS/umu assay was suitable to evaluate the genotoxic characteristics of the photoelectrocatalysis process due to its simplicity and sensitivity. Hence it could be employed as part of the assessment system for the environmental safety of photoelectrocatalysis process.