基于SOS/umu试验评价人工湿地污水回用致癌风险

Carcinogenic Risk Assessment of Wastewater Reuse in Constructed Wetland Based on Genotoxic Activities Using SOS/umu Test

SOS/umu试验能够快速、准确地检测水体中污染物产生的遗传毒性效应。利用SOS/umu试验对污水处理厂出水在人工湿地净化过程中产生的遗传毒性效应进行了测试。试验中两组水样的阳性对照4-硝基喹啉-1-氧化物当量浓度分别从312和389 ng/L下降至42和45ng/L,去除率分别为86.5%和88.4%,净化后两湿地出水的个体致癌年风险值在9.01×10^(-13)~8.13×10^(-12)之间,均远低于美国环保局提出的最大可接受水平。污水处理厂出水经人工湿地净化后遗传毒性效应显著降低,作为景观用水时致癌风险在可接受范围内。

The SOS/umu test can quickly and accurately assess the genotoxicity of pollutants in water.The genotoxicity of water samples from constructed wetlands was investigated using SOS/umu test.The results demonstrated that,in two groups of water samples,4-NQO equivalent concentrations fell to 42ng/L and 45 ng/L from 312 ng/L and 389 ng/L,and the removal rate reached 86.5%and 88.4%,respectively.The annual carcinogenic risks of the purified wastewater from constructed wetland were 9.01×10^(-13)-8.13×10^(-12),which were substantially lower than the maximum acceptable level specified by USEPA.The test showed that genotoxicity of wastewater was reduced significantly during constructed wetland purification,and the carcinogenic risk when used as landscape water was acceptable.