Influence of cadmium on Tetrahymena pyriformis in axenic culture.

Growth of Tetrahymena pyriformis (Gl) was studied in axenic culture in the presence of cadmium. The maximum growth rate is not affected by concentrations of cadmium below 1.5 mg/l (1.3×10 M). The concentration reducing the growth rate to 50% of its initial value is 2.6 mg/l (2.3×10 M) and the lethal dose is 5 mg/l (4.5×10 M). The mean cell volume, mean cell dry weight, mean cell protein content, yield and respiration rate were compared at 0, 0.2 and 2.0 mg/l Cd. No significant differences were detected for these parameters between control and treated groups. [ABSTRACT FROM AUTHOR]