水中铜离子对颤蚓的毒性效应研究

测定了铜对颤蚓的半数致死浓度(LC5)0、生物富集系数(BCF)、超氧化物歧化酶(SOD)活性的影响。实验结果表明随着铜浓度的增大,颤蚓的死亡率明显升高,铜对颤蚓毒性有明显的剂量—效应关系;铜对颤蚓的24h-LC50、48h-LC50、72h-LC50分别为237.8、212.2、174.3μg/L,表明染毒时间越长,铜对颤蚓的毒性越大;浓度为12.5μg/L、25μg/L的铜对颤蚓的BCF分别为25.3和36.8,表明暴露浓度越大,生物富集程度越高;暴露于浓度为0、5、10、15、20、25μg/L的铜溶液24h后,颤蚓体内SOD活性的变化呈现降低-升高-降低的趋势。实验表明颤蚓对铜的耐受能力较强且具有一定的生物富集作用。

Toxic Effect of Copper Ion on Tubifex

50% length rate concentration(LC50),biological concentration factor(BCF)and effect of copper on superoxide dismutase(SOD)activity were studied.Mortality rate of Tubifex was significantly raised gradually along with increase of copper concentration,indicating that there was a dose-effect relationship of the toxic of copper ion to Tubifex.24h-LC50,48h-LC50 and 72h-LC50 of copper ion to Tubifex were 237.8μg/L,212.2μg/L and 174.3μg/L respectively,which suggested that toxic effect of copper to Tubifex and exposed concentration was a direct-proportion relationship.With the copper ion concentration of 12.5μg/L and 25μg/L,BCF of copper ion to Tubifex were 25.3 and 36.8 respectively,which showed that BCF increased accompany with the expose concentration.Determent of SOD activity to Tubifex exposed for 24h in copper solution with concentration of 0μg/L,5μg/L,10μg/L,15μg/L,20μg/L and 25μg/L tended to decrease-increase-decrease.The experiment showed that Tubifex had strong copper toxic-resistant capability and could biological accumulate copper.