Cadmium biological half-life, humans

Cadmium is a cumulative toxicant with a biologic half-life of up to 30 years in humans. More than 70% of the cadmium in the blood is bound to red blood cells accumulation occurs mainly in the kidney and the liver, where cadmium is bound to metallothionein. In humans the critical target organ after long-term exposure to cadmium is the kidney, with the first detectable symptom of kidney toxicity being an increased excretion of specific proteins. 

Cadmium has a long biological half-life, 10 to 12 years in humans thus low-level chronic exposure will eventually result in accumulation to toxic concentrations. 

Cadmium is a highly cumulative poison with a biologic half-life estimated at about 20 to 30 years in humans. About half of the body burden of cadmium is found in the liver and kidneys. The total body burden reaches a plateau in humans around age 50. Cigarette smoke is a source of cadmium, and the body burden of cadmium is about 1.5 to 2 times greater in smokers than in nonsmokers of the same age. 

Cadmium is accumulated extraordinarily strongly in the human body. In newborn infants, the total cadmium amount is usually approximately 1 pg and by the 50th year of life the total amounts may be as high as 20 to 30 mg. In man, the value of the cadmium biological half-hfe ranges between 10 and 30 years. The kidneys, liver, lung and testes are the critical organs... 

The excretion of cadmium via the urine and feces is very low in normal human beings and the biological half-life is probably between 10 and 30 yr for the total body. ... 

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