成组生物毒性测试法综合评价典型工业废水毒性

为了更加准确地评估典型工业废水的综合生物毒性以及处理工艺对废水毒性的削减情况,采用发光细菌急性毒性实验、大型溞急性毒性实验和单细胞凝胶电泳实验,结合潜在生态毒性效应探测(potential ecotoxic effects probe,PEEP)指数对常州市7种典型工业废水的综合生物毒性进行了评价。结果表明,7种工业原水都表现出了急性毒性或遗传毒性,综合生物毒性强度的排序为电子厂>电镀厂>综合污水处理厂>印染厂>化工厂>食品厂>制药厂。而7种工业废水的处理后出水综合生物毒性强度的排序为印染厂>化工厂>电子厂>综合污水处理厂>食品厂>制药厂>电镀厂。其中,印染和化工厂出水综合生物毒性高于原水,分别增加了43.3%和38.7%,PEEP评价结果显示分别属于剧毒和高毒,而电镀、电子、综合污水处理和食品厂出水的综合生物毒性削减明显,分别比原水削减了76.9%、53.1%、48.3%和26.6%,PEEP结果表明基本无毒。建立在成组生物毒性实验基础上的PEEP评价方法可全面反映工业废水的综合生物毒性,进而更客观地评价废水对水生态系统乃至人类健康的潜在影响。

Synthetic Evaluation on Toxicity of Typical Industrial Effluents Using a Battery of Bioassays

To accurately evaluate the comprehensive toxicity of typical industrial effluents and the toxic reduction rate by different treatment processes, potential ecotoxic effects probe (PEEP) index was used to evaluate the biotoxicity of seven typical industrial effluents in Changzhou City, based on luminescent bacteria acute toxicity test, Daphnia magna acute toxicity test and single cell gel electrophoresis test. Results indicated that all raw effluents from the seven industries showed either acute toxicity or genetic toxicity, and the descending order of toxicity was as below: electronics plant, electroplating plant, comprehensive wastewater treatment plant, printing and dyeing plant, chemical plant, food plant, and pharmaceutical plant. After treatment, the descending order of toxicity among the seven industrial effluents changed as below: printing and dyeing plant, chemical plant, electronics plant, comprehensive wastewater treatment plant, food plant, pharmaceutical plant, and electroplating plant. Treated effluents of printing and dyeing plant as well as chemical plant were even more toxic than raw effluents, whose toxicities increased by 43.3% and 38.7%, respectively, being classified as very highly toxic and highly toxic grade by PEEP index. Nevertheless, the biotoxicities of treated effluents of electroplating plant, electronics plant, comprehensive wastewater treatment plant and food plant were reduced significantly by 76.9%, 53.1%, 48.3% and 26.6%, respectively, being classified as non-toxic grade. Based on the battery of bioassays, PEEP index can be used to reflect synthetic toxicity of effluents completely to estimate the potential effects of effluents on aquatic ecosystem and human health.