Mutagenic properties of cadmium sulfate were analyzed by the method of sister chromatid exchanges (SCEs) in lymphocytes of human peripheral blood taken from 4 donors. No significant increase was found in the mean frequency of SCEs in lymphocytes exposed to 1.6 X 10(-3) mM, 3.1 X 10(-3) mM and 6.2 X 10(-3) mM CdSO4 in culture.