Nickel (Ni) in urine

Nickel is a heavy metal whose compounds are toxic when accumulated in the body. It is normally present in humans in very low concentrations, but its physiological role has not been established.The main ways in which nickel enters the body are through water and food, which have higher concentrations of the metal. It is found in foods such as tea, coffee, chocolate, beans, tree nuts, cabbage, spinach and potatoes.  Every day a person consumes about 175 µg of nickel from food, which, however, is not enough to develop any symptoms of intoxication.  Another source of nickel is polluted air. A non-smoker inhales 0.1-0.25 µg of nickel per day (for metallurgical workers this figure may exceed 1 µg). Inhalation is the main route of intoxication at work. Smoking increases nickel intake by 0.0004 µg per day. Also important is the ingestion of this element through the skin and mucous membranes by prolonged contact with nickel-containing jewellery, coins, stainless steel objects. Elemental nickel does not penetrate through intact skin, but the absorption of nickel chloride and nickel sulphate is 77 %.