某制药废水对发光细菌急性毒性的评价研究

Evaluation of the Acute Toxicity of Pharmaceutical Wastewater to Luminescent Bacteria

采用发光细菌法测试某制药厂废水处理站工艺流程中5个节点废水的急性毒性.地下调节池水样EC50为3.44%,TUa为29,LID为625,为极强/高毒废水;地上调节池水样EC50为2.46%,TUa为41,LID为244,为极强/高毒废水;中间沉淀池水样EC50大于100%,LID=10,毒性较弱;二级沉淀池和总排放出口的废水EC50均大于100%,且LID均为1,无毒性.结果表明,现有处理工艺流程有效降低了制药废水对发光细菌的急性毒性,总排出口废水对发光细菌已经没有可见的生物毒性,达到相关制药废水排放标准.同时发现,低浓度废水对发光细菌的发光度不但没有抑制,反而有一定的增强作用.

Acute toxicity of wastewater from 5 nodes of technological process in the pharmaceutical factory sewage treatment station was studied by luminescent bacteria tests. The EC50, TUa and LID of the wastewater in underground regulating tanks was 3.44% , 29 and 625, respectively, indicating the water was extremely/highly toxic ; for the wastewater in surface regulating tanks, the EC50, TUa and LID was 2.46% , 41 and 244, respectively, also extremely/highly toxic; for the wastewater in middle sediment tanks, the EC50 〉 100% and LID was 10, which was moderately toxic; for the. wastewater in secondary sediment tanks and the final effluents, the EC50 was above 100% and LID was 1, with no observed toxicity. The results indicated that the existing treatment process effectively reduced the acute toxicity of the pharmaceutical wastewater to luminescent bacteria, the effluents showed no observed toxicity to luminescent bacteria, which was lower than the relative effluent limits of pharmaceutical wastewater. The wastewater in lower concentration did not inhibit the luminosity, but enhanced the luminosity.