重金属Zn、Cu和Hg对基因重组发光菌的综合毒性及其联合效应

Toxicity and Joint Effects of Heavy Metals Zn,Cu and Hg to Recombinant Luminescent Bacterium

分析了3种常见重金属(Zn^(2+)、Cu^(2+)、Hg^(2+))对基因重组发光菌(E.coli HB101 pUCD607)的单一毒性和不同质量浓度比条件下的联合毒性作用,并采用毒性单位法(Toxic Unit)、Marking相加指数法(Additional Index)和混合毒性指数法(Mixture Toxicity Index)来评价混合体系的联合毒性作用类型.Zn^(2+)、Cu^(2+)和Hg^(2+)3种重金属离子对发光细菌的15 min半数效应浓度(EC50)分别为:4.24、5.99、2.27 mg/L.多元重金属离子混合体系主要呈现不同程度的拮抗作用,不同的评价方法对3种重金属离子的联合效应评价结果具有较好的一致性.上述重金属联合毒性作用研究结果可为重金属复合污染控制和生物毒性测试提供参考.

The toxicity of three common heavy metals( Zn^(2+),Cu^(2+),Hg^(2+)) and their joint toxicity at different concentration ratios to the recombinant luminescent bacterium( E. coli HB101 p UCD607) were analyzed. The toxic effects of the metal mixtures were evaluated by the Toxic Unit,Marking Additional Index and Mixture Toxicity Index. The median effective concentrations( EC_(50)) of the three heavy metals Zn^(2+),Cu^(2+)and Hg^(2+)were 4. 24,5. 99 and 2.27 mg/L for 15 min,respectively. The mixed system of heavy metals mainly showed antagonistic effects in different degrees. The results of the three heavy metals by three evaluation approaches showed good consistency with each other. The joint toxicity of the heavy metals provides basic information for the control of heavy metal compounds and biological toxicity test.