Cu2+、Zn2+、Al3+对泥鳅的单一和联合毒性研究

 本文研究了Cu²⁺、Zn²⁺、Al³⁺3种离子对泥鳅的单一和联合毒性。结果表明：Zn²⁺和Al³⁺对泥鳅24 h的半致死浓度（LC₅₀）分别为3.24和1.50 mg/L；Cu²⁺、Zn²⁺和Al³⁺对泥鳅48 h的LC₅₀分别为1.05、3.02和1.43 mg/L，对泥鳅72 h的LC₅₀则为0.67、3.02和1.39 mg/L，对泥鳅96 h的LC₅₀分别为0.56、2.87和1.35 mg/L；而Cu²⁺、Zn²⁺、Al³⁺ 3种离子对泥鳅96 h的安全浓度分别为0.0056、0.029和0.014 mg/L。采用Marking相加指数评价法进一步分析结果显示，Cu²⁺-Zn²⁺-Al³⁺混合溶液对泥鳅表现出拮抗作用（48和72 h）和协同作用（96 h）。

Effects of Cu2+, Zn2+, Al3+ on single and joint toxicities of loach

In order to study the acute toxicity of three kinds of ions (Cu²⁺, Zn²⁺, Al³⁺) on loach and the change of the processed loach liver antioxidant enzyme activity and lipid peroxidation, experiments have been conducted. The result shows that for loach exposed to Cu²⁺, Zn²⁺, Al³⁺ solutions, the 24 h half-lethal concentrations are Zn²⁺ 3.243 and Al³⁺ 1.497 mg/L; the 48h half-lethal concentrations are Cu²⁺1.054 mg/L, Zn²⁺3.017 mg/L and Al³⁺ 1.425 mg/L; the 72 h half-lethal concentrations are Cu²⁺ 0.666, Zn²⁺3.017 and Al³⁺ 1.386 mg/L; the 96 h halflethal concentrations are Cu²⁺ 0.563 mg/L, Zn²⁺ 2.874 mg/L and Al³⁺ 1.350 mg/L. The 96 h safe concentrations are Cu²⁺0.563 mg/L, Zn²⁺ 2.874 mg/L, and Al³⁺ 1.350 mg/L. Thus, the order of toxicity to loach from strong to weak is Cu²⁺>Al³⁺>Zn²⁺. For loach exposed to a Cu²⁺-Zn²⁺-Al³⁺ mixed solution, the 48 h, 72 h, the 96 h joint toxicity effect performances are respectively antagonistic action, antagonistic action, and synergy. The safe Zn²⁺ concentration of loach is 0.029 mg/L, which is far lower than 0.10 mg/L, the National Standard of Fishery Water Quality in China.