对二氯苯、四氯乙烯和镉联合污染对草鱼的毒性效应研究

Joint Toxicity of 1, 4-Dichlorobenze, Perchloroethylene and Cd^2+on Grass Carp

文章采用水生污染暴露试验和Marking相加指数评价法,研究了对二氯苯(P-DCB)、四氯乙烯(PCE)和重金属镉(Cd2+)对草鱼的联合毒性。结果表明:单一P-DCB、PCE和Cd2+污染对草鱼的24、48、72和96 h的半数致死质量浓度依次是10.11、9.04、8.52、7.97,46.13、41.58、36.51、34.56和45.58、34.81、28.63、24.05 mg/L;由此可见,它们的单一毒性均为高毒,并且其毒性顺序为P-DCB>Cd2+>PCE。P-DCB、PCE和Cd2+对草鱼的联合毒性,在浓度1∶1时,表现出暴露时间为24、48、72和96 h的相加指数分别为-0.75、-0.46、-0.32和0.11,联合作用结果为先拮抗作用,随着时间的增加,拮抗作用减弱,最后转为毒性剧增的协同效应。而在毒性1∶1时,表现出暴露时间为24、48、72和96 h的AI分别为-0.41、-0.37、-0.17和-0.14,所以联合作用结果是为拮抗作用,随着时间的增加,拮抗作用减弱。

The single and joint toxicity of 1,4-dichlorobenze(P-DCB),perchloroethylene(PCE)and cadmium(Cd2+)on grass carp was evaluated using the aquatic pollution-exposure experiment combined with the Marking additive index method.The single toxic tests showed that LC50 of 24,48,72,96 h for P-DCB was 10.11,9.04,8.52 and 7.97 mg/L,respectively;those for PCE acting on grass carp was 46.13,41.58,36.51,34.56 mg/L,respectively and those for Cd2+acting on grass carp was45.58,34.81,28.63,24.05 mg/L,respectively.Thus,P-DCB,PCE and Cd2+are such pollutants with the high toxicity,and the single toxic sequence of the chemicals was P-DCB>Cd2+>PCE.The joint toxicity of P-DCB,PCE and Cd2+to grass carp while their concentration was at the rate of 1∶1 in 24,48,72 and 96 h showed that the AI was-0.75,-0.46,-0.32 and 0.11,respectively.Thus,the joint toxicity of P-DCB,PCE and Cd2+was antagonism,to synergistic with time.However,the AI of24,48,72 and 96 h for P-DCB,PCE and Cd2+to grass carp while their toxicity was at the rate of 1∶1 was-0.41,-0.37,-0.17 and-0.14,respectively.The joint toxicity was antagonism,but the antagonism effect was decreasing with time.