تسجيل الدخول

تسجيل

Cadmium

المؤلف:  Sue Jickells , Adam Negrusz (Editors)

المصدر:  Clarkes Analytical Forensic Toxicology

الجزء والصفحة:  105

2026-09-22

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Cadmium

Cadmium and its salts and alloys are used in the manufacture of nickel–cadmium batteries, pigments and special alloys. Many of the risks associated with occupational and environmental exposure to cadmium have been known for many years. These include emphysema from the acute inhalation of cadmium fumes and, more long term, renal impairment (Jarup et al. 1988). Water supplies contaminated with industrial cadmium in Japan led to accumulation of the metal in rice and other dietary sources with subsequent human poisoning on a vast scale.

Those affected developed renal damage, skeletal deformities caused by disturbances of calcium and phosphate metabolism, and severe back and leg pain (Friberg et al. 1971). This painful condition became known as itai-itai (ouch-ouch) disease. For those not occupationally exposed, the major source of cadmium remains the diet, although it is absorbed poorly from the gut. Inhalation of tobacco smoke is another source of cadmium exposure, as the bioavailability of cadmium via the lung is very high and heavy smokers may have blood cadmium concentrations at the limit of current occupational guidance values. Following absorption, cadmium is stored mainly in the liver and kidney, where it is bound to metallothionein and stays in the body for decades. The most important toxic effect is on the kidney, with proximal renal tubular necrosis; this can be detected by a characteristic increase in the excretion of low-molecular weight proteins. Individuals who have a long history of excessive occupational cadmium exposure can have a high body burden, which persists into old age (Mason et al. 1999). Elevated blood and urine cadmium concentrations may be observed many years after the cessation of exposure in such individuals. Blood cadmium concentrations in non-smokers are <2 μg/L and in smokers <6 lg/L. Urine concentrations are generally below 1 μg/L in both smokers and nonsmokers. Cadmium-induced renal tubule impair ment is generally related to urine cadmium concentrations >15 μg/L.