Evaluation of the toxic effect of Cd2+ and Cd(CN)2-4 ions on the growth of mixed microbial population of activated sludges.

The effect has been studied of Cd2+ and Cd(CN)2-4 ions on the growth and enzymatic activity of mixed microflora from activated sludges. Both ions tested significantly inhibited the growth of microorganisms, estimated by means of the optical density, and the inhibitory effect of Cd2+ was significantly greater than that of Cd(CN)2-4 at the same mass and molar concentrations. There was also inhibition of the maximum uptake rate of glucose, but in this case there were no statistically significant differences between the inhibitory effect of the corresponding mass and molar concentrations of Cd2+ and Cd(CN)2-4.