五氯苯酚与邻氯苯酚和2,4-二氯苯酚对斑马鱼的联合毒性

在五氯苯酚(PCP)与邻氯苯酚(2-CP)和2,4-二氯苯酚(2,4-DCP)3种物质单一毒性试验结果的基础上,按照等毒性单位设计,采用相加指数法,对五氯苯酚(PCP)与邻氯苯酚(2-CP)或2,4-二氯苯酚(2,4-DCP)以及这3种物质共存对斑马鱼(Brachydanio rerio)的联合毒性进行了试验研究.结果表明,邻氯苯酚(2-CP)和2,4-二氯苯酚(2,4-DCP)与五氯苯酚的联合毒性效应均表现为协同作用,使五氯苯酚的毒性剧增.由于邻氯苯酚或2,4-二氯苯酚的存在以及3种物质共存,使五氯苯酚对斑马鱼的48 h LC50由原来的0.102 mg/L,分别下降到0.031,0.029及0.022 mg/L.因此可见,水体污染评价目前只考虑单一毒物的影响还远远不够,由此制定的控制标准对水体的保护不利,必须从联合毒性的角度对水质污染进行综合评价. 

Joint Toxicity Effects of PCP,2-CP and 2,4-DCP to Zebrafish

Joint toxicities of pentachlorophenol(PCP) with 2-chlorophenol(2-CP),PCP with 2,4-dichlorophenol(2,4-DCP) and PCP with 2-CP and 2,4-DCP to zebrafish(Brachydanio rerio) were determined based on the single toxicities of the three compounds,in which Additive Index Method was used to evaluate the joint toxic effects.The results show that the joint toxicities of PCP with 2-CP,PCP with 2,4-DCP and PCP with 2-CP and 2,4-DCP were all synergistic.The toxicity of PCP is increased as following: 48 h LC_(50) of PCP drops to(0.031,)(0.029) or(0.022)(mg/L) from the single toxicity of(0.102)(mg/L) due to the joint toxicities.Accordingly it is not enough to do water pollution evaluation only based on single toxicities of the compounds.It should be based on joint toxicities of all pollutants.