Effects of Cd~(2+)、Pb~(2+) and Hg~(2+) on Colpoda inflata

The toxic effects of heavy metal ions,Hg2+,Pb2+ and Cd2+ on Colpoda inflata were studied.It is showed that the growth of C.inflata had been inhibited significantly under different concentrations of heavy metal ions.The acute toxicities of Cd2+,Pb2+ and Hg2+ to C.inflata were in the sequence of Hg2+,Pb2+,Cd2+.The results of joint toxicity showed that the types and magnitudes of joint actions were different at different solution compositions.The joint toxicity of Cd2+ and Pb2+ at the concentration proportion 1∶1 and toxic proportion 1∶1 were all antagonism.At the concentration proportion 1∶1,the joint toxicity of Pb2+ and Hg2+ was synergistic,and it changed from antagonism to synergistic at the toxic proportion 1∶1.The joint toxicity of Hg2+ and Cd2+ at the concentration proportion 1∶1 was synergistic,and it was antagonist at toxic proportion 1∶1.At the concentration proportion 1∶1∶1,the joint toxicity of Cd2+,Pb2+ and Hg2+ was synergistic,and it changed from antagonism to synergistic under toxicity proportion 1∶1∶1.