废弃农药厂污染场地土壤浸出液的急性毒性和遗传毒性筛查

污染土地再开发是城市土地可持续利用的关键。为进行废弃农药厂的生态风险评价,采集常州市某废弃农药厂污染场地6个不同区域的土壤样品(编号为S1、S2、S3、S4、S5和S6),选取发光细菌、大型溞和蚕豆根尖细胞为试验生物,运用成组生物毒性试验对6个土壤样品的浸出液进行生物毒性检测。结果表明:6个土壤样品的浸出液都具有急性毒性和遗传毒性;发光菌和大型溞急性毒性试验表明,S3和S5的土壤浸出液毒性最高,S6的土壤浸出液毒性最低;蚕豆根尖微核遗传毒性试验表明S3和S5的土壤浸出液毒性最高,S4和S6的土壤浸出液毒性最低。蚕豆根尖微核遗传毒性试验结果与发光菌和大型溞急性毒性效应基本相同,表明成组生物毒性测试法可以用于污染土壤浸出液的毒性评价。污染物质和毒性检测结果的相关性分析结果表明,土壤中所含污染物种类和浓度已经对土壤毒性效应产生影响,结合化学分析与生物毒性检测可为污染场地进行综合评价与风险评估提供依据。

Screening of Acute Toxicity and Genetic Toxicity of Soil Leachates from Abandoned Pesticide Factory Contaminated Site

The redevelopment of contaminated land is the key factor on sustainable utilization of urban land. For the ecological risk assessment of abandoned pesticide plant, six soil samples (S1, S2, S3, S4, S5, S6) were collected from different regions of contaminated soil in an abandoned pesticide factory in Changzhou. Luminescent bacteria, Daphnia magna, Vicia faba were chosen as experiment materials using a battery of bioassays to detect biological toxicity of leachates of six soil samples. Results indicated that the six leachates had acute toxicity and genetic toxicity. Acute toxicity of luminescent bacteria and Daphnia magna test showed that the toxicity of leachates of S3 and S5 soil samples was the highest, and the toxicity of leachate of S6 soil sample was the lowest. Micronucleus genetic toxicity test on Vicia faba root tip indicated that the toxicity of leachates of S3 and S5 soil samples was the highest, and the toxicity of leachate of S4 and S6 soil sample was the lowest. The effect of micronucleus genetic toxicity and the luminescent bacteria, Daphnia magna acute toxicity showed the same trend basically, indicating that a battery of bioassays can be used to evaluate the toxicity of contaminated soil leachates. Correlation analysis between pollutant and toxicity test results showed that the types and concentrations of pollutants in the soil had an impact on soil toxicity. The combination of chemical analysis and toxicity test can provide a basis for comprehensive evaluation and risk assessment of contaminated sites.