Cadmium

Cadmium (Cd) is a heavy metal widely used within industry. It currently has no known biological role. Acute ingestion of cadmium salts can cause nausea and vomiting and inhalation of cadmium fumes develops a ‘metal fume fever’; a pneumonitis with cough, dyspnoea and also myalgia. Cadmium is transported to the liver by plasma proteins where it is bound to metallothionein. This complex is then transported to the kidneys, where the cadium-metallothionein complex dissociates leading to proximal renal tubular damage. Tobacco contains significant concentrations of cadmium, such that smokers may have blood cadmium concentrations that are 4–5 times greater than those of non-smokers. The preferred sample for the measurement of cadmium is whole blood. Cadmium can also be measured in urine but should only be undertaken when blood cadmium indicates significant exposure.