铜、锌和铅对大型溞的联合毒性效应

The Joint Toxic Effects of Copper,Zinc and Lead to Daphnia magna

以大型溞为试验对象,探究了铜、锌、铅三种重金属单一作用和两两联合作用对大型溞的毒性效应。结果表明:在铜、锌、铅单独作用下,大型溞的96 h半致死质量浓度分别是0.0576、0.3459和13.8100 mg/L;大型溞的安全质量浓度分别是0.0006、0.0035和0.1381 mg/L。这三种重金属作用于大型溞的毒性大小为:铜>锌>铅。通过非线性联合评价方法,分别测定出三种重金属两两联合(Cu+Zn、Cu+Pb、Zn+Pb)作用下大型溞48 h实际致死率均高于理论致死率,表明这三种重金属两两联合对大型溞的毒性效应表现为协同作用。

Therefore,it is necessary to study their combined toxicity to aquatic organisms.In this paper,Daphnia magna was used as and experimental organism to investigate the individual to explore the single toxicity of Cu,Zn and Pb,as well as their combined toxic effect.The results showed that the 96-h LC 50 values for Cu,Zn and Pb in D.magna were 0.0576 mg/L,0.3459 mg/L and 13.8100 mg/L,respectively.The safe concentrations(SC)of Cu,Zn and Pb in D.magna were 0.0006 mg/L,0.0035 mg/L and 0.1381 mg/L,respectively.The toxicity level order of these three heavy metals to D.magna was Cu>Zn>Pb.Using the non-linear joint evaluation method,it was found that the actual 48-h lethality rates of pairwise combination of three heavy metals(Cu+Zn,Cu+Pb,Zn+Pb)to D.magna were higher than the theoretical lethal rates.This indecates that the toxic effect of the combination persence of these three heavy metal ions on D.magna exhibited a synergistic effect.