Nickel is a silvery white metal that takes on a high shine. It belongs to the transition metals, and is hard and ductile. It occurs most commonly in combination with sulfur and iron. It is used in coins, for plating iron, brass, etc., for chemical apparatus, and in certain alloys, such as German silver. It is magnetic, and is very frequently accompanied by cobalt, both being found in meteoric iron. It is chiefly valuable for the alloys it forms, especially many super alloys, and particularly stainless steel. Nickel and compounds can be inhaled or ingested, and often cause a contact reaction.
Nickel is a naturally occurring silvery metal found in the earth's crust in the form of nickel-containing minerals. Elemental nickel is recovered from mined ore and from scrap metal. Nickel is ubiquitous in industry. It is used in the manufacture of steel and many alloys, dyes, paints, and magnetic tapes. It is also found in diesel fuel. Nickel is used in electroplating, in nickel-cadmium batteries, and in ceramics and jewelry manufacture.1
Sources
Cigarette smoke, tobacco, meats and
seafood, vegetation, drinking water, coins, magnets, stainless steel,
jewelry, manufacturing facilities (multiple alloys).
Physiological Effects
An allergic skin reaction is the most
common adverse health effect in people who are sensitive to nickel. Once
a person is sensitized to nickel, further contact with nickel will
produce a reaction, most commonly a skin rash at the site of contact
(dermatitis). Less frequently, some sensitized persons may have asthma
attacks following exposure to nickel. Some people may react when they
eat nickel in food, drink it in water, or breathe dust containing it.
The most serious health effects occur when nickel is inhaled. This can
result in: an increased risk of respiratory cancer due to chronic
inhalation of fumes or fine particles when the exposure is to known
carcinogenic forms like nickel oxide; asthma, nasal and sinus problems.
1 - http://www.mdguidelines.com/toxic-effects-nickel-and-inorganic-compounds
