死鱼事件中污染源废水对鱼类急性毒性及诱变微核的研究

Fish acute toxicity and micronucleus test of chemical factory discharge during fish killing accident

为了研究2006年9月广州郊区某鱼塘因化工企业污染源废水进入而导致大量死鱼事件中鱼类死亡原因,用斑马鱼(Brachydanio rerio)和蚕豆(Vicia faba)根尖对污染源废水及鱼塘水分别进行了鱼类急性毒性试验和蚕豆根尖微核试验。污染源废水和鱼塘水的96hLC50分别为1.69%、23.95%,污染源废水和鱼塘水的微核率分别为27.8‰、13.7‰,污染源废水和鱼塘水的COD、BOD、石油类、氨氮、总磷等均出现超标情况,其中氨氮、苯胺、石油类污染物严重超标。监测结果表明,以氨氮污染为主的污染源废水是导致死鱼事件的主要原因,废水对蚕豆根尖微核率的形成具有显著性影响,可能存在潜在的致突变性危险。

In order to understand the cause of a fish killing accident occurred in a fish pond in Guangzhou in September 2006, fish acute toxicity test by Brachydanio Rerio and root tip micronucleus test by Vicia faba were conducted with the contaminated water. 96h LC50 values of water samples from a chemical factory discharge area and the central pond were 1.69%, 23,95%, respectively; micronucleus frequencies were 27.8%0, 13.7%o respectively. COD, BOD, oils, NH3-N, TP of both water samples were over-standard. The result showed that effluent of the chemical factory is the main cause of fish kills. Moreover, the effluent significantly enhanced the micronucleus frequencies, and increased the risk of potential mutagenicity.