镉对异育银鲫的急性毒性

Acute Toxicity of Cadmium to Allogynogenetic Silver Crucian Carp

在水温(22.0±2.0)℃下,用纯度≥99%的分析纯CdCl_2·2.5H_2O配制成镉浓度为15.000～40.040mg·L^(-1)溶液,采用静态毒性试验法研究镉对平均体质量(34±0.2)g的异育银鲫Carassius auratus gibelio的急性毒性,观察异育银鲫染毒后的症状。结果表明:异育银鲫死亡率随镉离子浓度升高和暴露时间延长而增加,具有明显的剂量-时间效应关系;在24h、48h、72h、96h时,镉对异育银鲫的半致死浓度(LC_(50))分别为36.297 mg·L^(-1)、32.263mg·L^(-1)、28.677 mg·L^(-1)和26.510 mg·L^(-1),安全浓度(SC)为2.651 mg·L^(-1)。可见,镉对异育银鲫为低毒物质,异育银鲫对镉有较强耐受性。

The acute toxicity of cadmium at concentrations of 15.000 ~ 40.040 mg·L-1 prepared by AR CdCl2·2.5H2O(>99%)to allogynogenetic silver crucian carp Carassius auratus gibelio with average body weight of(34 ± 0.2) g was studied at water temperature of(22.0 ± 2.0)℃ by static toxicity test in order to explore the susceptibility of allogynogenetic silver crucian carp to cadmium and the toxic effect of cadmium on allogynogenetic silver crucian carp. The results showed that the mortality of allogynogenetic silver crucian carp was found to be increased with the increase in cadmium ion concentration and exposure time, with remarkable dose-time-effect. The median lethal concentration(LC50)was 36.297 mg·L-1 at 24 h, 32.263 mg·L-1 at 48 h, 28.677 mg·L-1 at 72 h and 26.510 mg·L-1 at 96 h, with safe concentration(SC)of 2.651 mg·L-1. The findings showed that cadmium is a poisonous substance to allogynogenetic silver crucian carp which has strong sensitivity to cadmium.