Hypocalcaemia in experimental cadmium poisoning.

Renal stones, hypercalciuria, and radiological bone changes have been found in workers exposed to compounds containing cadmium. In the present experiments the effect of cadmium chloride injections on the serum calcium levels of rabbits has been studied. Repeated subcutaneous injections over a period of two weeks at a dosage of up to 0·04 mmole/kg. body weight produced a slight but consistent fall in the serum calcium level by about 2 mg./100 ml. Vacuolation of the parathyroids occurred in a few animals. Single intravenous injections of cadmium chloride, at dosages of 0·01, 0·015, and 0·02 mmole/kg. body weight, produced falls of between 2 and 4 mg./100 ml. in the serum calcium level measured six hours later. In animals which survived the level was still low at 24 hours, after which the serum calcium returned to normal levels. The degree of hypocalcaemia was proportional to the dose of cadmium used. It is suggested that this fall in the serum calcium level may have been due to increased renal excretion.