重金属离子对裸体方格星虫的急性毒性试验

目的]研究Cu2＋和Hg2＋对裸体方格星虫的急性毒性。方法]采集裸体方格星虫于实验室暂养3～4 d后,选用健康和规格一致个体进行试验。分别选用Cu2＋浓度为0.350、0.408、0.477、0.556和0.649 mg/L,Hg2＋浓度为0.400、0.480、0.576、0.691和0.829 mg/L进行急性毒性试验。结果]裸体方格星虫对Cu2＋和Hg2＋的耐药性均随试验时间延长而缓慢降低。Hg2＋对裸体方格星虫24和48 h半致死浓度分别为0.615和0.374 mg/L,Cu2＋对裸体方格星虫24和48 h半致死浓度分别为0.497和0.407 mg/L。结论]Cu2＋和Hg2＋均对裸体方格星虫具有毒性效应。

Experimental Evaluation of Acute Toxicity of Heavy Metal Ions on Sipunculus nudus

Objective] To investigate the toxic effects of two kinds of heavy metal ions(Cu2+ and Hg2+) on Sipunculus nudus.Method] After Sipunculus nudus individuals were cultured for 3-4 d,the healthful individuals(3.636±0.569 g in mean total weight) were sampled and then subjected to the experiment where acute toxicity testing of Cu2+ and Hg2+ were tested.The concentration levels of Cu2+ set in the present experiment were 0.350,0.408,0.477,0.556 and 0.649 mg/L,respectively.The concentration levels of Hg2+ were 0.400,0.480,0.576,0.691 and 0.829 mg/L,respectively.Result] It was found that the resistance of Sipunculus nudus against the two heavy metals decreased slowly as the experiment time lasted.The LC50 of Cu2 + and Hg2+ were 0.497 and 0.615 mg/L after 24 h and 0.407 and 0.374 mg/L after 48 h,respectively.Conclusion] That Cu2+ and Hg2+ had high toxicity effects on Sipunculus nudus.