The most common malady experienced by people who come into contact with nickel is a skin rash called contact dermatitis. This condition can be caused by direct handling of nickel-containing objects common in most households.
Coins, plumbing fixtures, certain shampoos and detergents, pigments and jewelry can contain small amounts of nickel that can be absorbed through the skin. Over time, direct skin contact with these objects may cause a person to become sensitized to the metal and to experience an allergic reaction to nickel.
For example, wearing earrings made from metal containing nickel could sensitize an individual to the element. Scientists believe that nickel in the jewelry dissolves in sweat absorbed into the skin. A skin rash at the site of contact is the most common result of such a reaction. In more acute cases, asthma attacks have been reported. Once a person has become sensitized to the substance even nickel ingested through food may trigger allergic symptoms.
For this reason allergists recommend that severe nickel allergy sufferers lower their dietary intake of nickel by avoiding certain foods, shown in the box below. Like most environmental agents, the toxic effect of any metal is related to the way it gets into an organism or, in the language of toxicology, its route of exposure.
Nickel has three main routes of exposure. It can be inhaled, ingested or absorbed through the skin. When nickel is inhaled, gaseous nickel compounds like nickel subsulfide or small particles of nickel dust specifically, PM In the case of inhalation exposure, scientists have found the form of nickel and its solubility is a key determining factor in the resulting toxicity mechanisms.
Water-soluble nickel compounds can be absorbed by the lungs into the bloodstream and eventually removed by the kidneys. Poorly soluble nickel compounds, however, can build up in the lungs, over time and cause complications such as pulmonary fibrosis, a buildup of scar tissue in the lungs as well as bronchitis and lung cancer. The mechanism that enables nickel to cause or contribute to cancer is still very poorly understood.
Certain forms of nickel are carcinogenic, or cancer-causing, but these forms are not likely to be encountered outside of industrial settings, such as factories where metals are processed, particularly where nickel ore is refined and where stainless steel is produced. Other workers who may be exposed to these forms of nickel are welders, electroplaters, battery makers, jewelers, spray painters, paint makers and varnish makers. Workers in metal industries who were exposed daily to nickel dust in the form of nickel carbonyl or nickel subsulfide have been found to have a higher incidence of nasal, sinus and lung cancers.
Inhalation exposure to nickel dust can also result in chronic bronchitis, acute respiratory distress syndrome and pulmonary fibrosis.
Levels of nickel dust and nickel compounds in the air at industrial facilities processing nickel ores and alloys prior to the s were , to 1 million times greater than typical background levels found in the air throughout the United States. Environmental Protection Agency has since determined that nickel refinery dust, nickel subsulfide and nickel carbonyl are human carcinogens in these occupational settings.
The Occupational Safety and Health Administration OSHA drafts and enforces federal regulations related to nickel and other toxic substances to protect workers from harmful exposures such as these. OSHA has determined that nickel levels in air at the workplace may not exceed 1 microgram per cubic meter. These policies have helped to lower nickel dust exposure among workers in metal industries. What is Nickel? What are the uses of Nickel?
Is Nickel Necessary for Health? Schlag was an auto stylist for General Motors. An American explorer designed his own boat Captain Meriwether Lewis drew up the plans for the keelboat shown on the Keelboat nickel. The foot keelboat was built in Pittsburgh, Pennsylvania. It could be sailed, rowed, poled like a raft, or towed from the riverbank. It's the only U. The rest is copper. The portrait on nickels made before was based on a marble bust by the French sculptor Jean-Antoine Houdon.
The sculpture was completed in , while Jefferson was still alive, and is said to look just like him. The President got the first Jefferson nickel The coin, issued on November 6, , was presented to President Franklin D.
Total daily dietary intakes of nickel vary depending on the amount of plant and animal foods consumed. Diets high in plant foods, such as the ones listed above, supply about micrograms daily of nickel. Nickel intake in the United States ranges from 69 to micrograms daily. A daily dietary requirement of 25 to 35 micrograms has been suggested.
END Nickel may be found in prepared foods tinned foods at markedly higher concentrations than the safe threshold laid down for hypersensitive patients.
Some foodstuffs cooked in stainless-steel utensils react with the metal and thus contain much more nickel than when enamel or aluminium saucepans are used. Among the natural organic acids, which may be responsible for dissolving stainless-steel, oxalic acid is the most active at equivalent concentrations. Source: Contact Dermatitis. Nickel in food: the role of stainless-steel utensils.
The normal daily intake of nickel by American adults is about 0. The nickel content of food is partially determined by the components of the soil in which the food was grown, pesticides used on it and the equipment used in the handling of the food. Nickel in food may vary considerably from region to region.
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