不同价态Mn离子对刺参幼参急性毒性效应及富集作用

Acute toxicity and accumulation of Mn ions with different valences on larval Apostichopus japonicas

静水条件下,研究了Mn^2＋与Mn^7＋对刺参幼参行为和存活的影响,并分析了其在幼参体内的富集状况。结果表明,幼参在0.8～16 mg/L浓度范围内的Mn^2＋暴露96 h后死亡率均为0.0%,Mn^2＋在此浓度范围内无明显的急性毒性作用;但暴露于0.1～6.5 mg/L Mn^7＋中时,幼参的死亡率随浓度和暴露时间增加而升高。暴露48 h时,幼参的死亡率与Mn^7＋的浓度呈极显著正相关（P〈0.01）,Mn^7＋浓度高于0.5mg/L时即对幼参表现出明显的急性毒性作用,其安全浓度（SC）为0.31 mg/L,Mn^7＋对幼参的急性毒性作用强于Mn^2＋。随着水体中Mn^2＋与Mn^7＋浓度的增加,幼参体内Mn元素含量和累积速率均逐渐升高,但富集系数变化存在较大差异。Mn^7＋在幼参体内的富集作用强于Mn^2＋。

Using static bioassay test,the acute toxicity of Mn^2＋ and Mn^7＋ on behavior and survival of juvenile sea cucumber Apostichopus japonicas was studied,furthermore,the accumulation in Ap. Japonicas was also analyzed. The results showed that at 96 h of exposure,the mortality rates of Ap. Japonicas were 0. 0 % in all groups of Mn^2＋treatment,no significant acute toxicity of Mn^2＋was found within the experimental concentration range of 0. 8 ～ 16 mg / L;However,when exposed to Mn^7＋within the range of 0. 1 ～ 6. 5 mg / L,the mortality rate increased with the Mn^7＋ concentration and exposure time. At 48 h of exposure,the mortality rate of larval Ap. Japonicas showed a significant positive correlation with Mn^7＋ concentration（ P〈0. 01）. Mn^7＋ at concentrations higher than 0. 5 mg / L showed the significant acute toxicity,and its safety concentration（ SC） for the juvenile sea cucumber was 0. 31 mg / L. Therefore,Mn^7＋ had the stronger acute toxicity than Mn^2＋ to Ap. Japonicas. With increasing concentrations of Mn^2＋ and Mn^7＋,the Mn content and accumulation rates in juvenile bodies gradually increased,but changes in bioconcentration factor differed between Mn^2＋ and Mn^7＋.