The effect of heavy metals on vitamin A metabolism

Three kinds of divalent ions were injected subcutaneously to rats. Copper at the total dose of 6.2 mg/kg and zinc at the total dose of 12.6 mg/kg did not alter the plasma or liver vitamin A (VA) concentrations. The liver concentration of both had returned to control levels by 2 weeks after the final injection. Cadmium, at the total dose of 6.2 mg/kg, decreased significantly the plasma level of VA, although the liver VA content was not affected. This effect persisted till 2 weeks after the final injection.