Nickel

Nickel is a shiny silver-white element and is a ferromagnetic heavy metal. It has the atomic number 28 in the periodic table of elements. Nickel was named after mining spirits ('nickel goblins') who fooled the medieval miners into believing that the then worthless nickel ore was silver. It is the 21st most abundant element on the earth's surface. It is known that the Chinese were already using nickel-copper compounds in the year 2000 BC. It was discovered by the Swedish mineralogist and chemist Frederick Cronstedt (1722-1765) in 1751. Nickel only occurs as a pure metal in meteorites that have reached the earth. Otherwise it is found as magnetic pyrite (pyrrhotite), white nickel pyrite (cobalt nickel arsenide), red nickel pyrite (nickel arsenide) or yellow nickel pyrite (nickel arsenide). In the technical industry, it is mainly used to refine steel. Nickel is also used in the production of coins and is contained in dishes and laboratory instruments. Nickel is vital (essential) for many organisms. Whether the same applies to humans has not yet been clearly established. However, nickel could be important for some enzymes and the metabolism of certain hormones and could be involved in the formation of nucleic acids in the cell nucleus. Nickel also appears to play a role in the storage of glycogen in the liver.

Functions in the body

The body of an adult with an average body weight of 70 kg contains a few milligrams of nickel, which is mainly found in hormone-producing glands, lungs, liver and kidneys. Nickel is a component of a number of enzymes such as urease. Urease breaks down urea into carbon dioxide and ammonia. The enzymes that process or stabilize DNA and RNA also contain relatively high levels of nickel.

Deficiency symptoms

A lack of nickel leads to a disruption of the respiratory chain (citric acid cycle) because nickel is a component of some of the enzymes involved. It can also lead to metabolic disorders during glucose breakdown. Due to the involvement of nickel in urease, the enzyme that breaks down urea, nickel deficiency may lead to uremia, i.e. an increased concentration of urea in the blood.

Safety and side effects

Nickel is safe and harmless for most adults in quantities of up to 1 mg per day. More than 1 mg per day may not be safe and harmless. Taking amounts slightly higher than 1 mg per day could increase the risk of adverse side effects. High doses are toxic.

Nickel allergy is relatively common. It is assumed that up to 10% of women and around 1% of men have an allergic-inflammatory reaction to skin contact with nickel compounds, resulting in contact dermatitis. Triggers are usually watches and jewelry containing nickel. The metal buttons of pants, especially jeans, also frequently contain nickel. Studies on people who work in nickel-processing plants or refineries show a much higher incidence of lung and nasal cancer. Nickel has also been found in tobacco. It is possibly one of the cancer-causing (carcinogenic) components in tobacco smoke. As with all heavy metals, extreme overdose, which is very rare, can lead to various severe symptoms of poisoning.

Precautions and warnings

Pregnancy and breastfeeding: Nickel is safe and harmless for pregnant and breastfeeding women when taken in amounts below the upper tolerated level of 1 mg per day. Nothing is known about the safety of higher amounts.

Children: Nickel is safe for children at levels below the upper tolerated level of 0.2 mg per day for children 1 to 3 years of age, 0.3 mg per day for children 4 to 8 years of age, and 0.6 mg per day for children 9 to 13 years of age. Use of larger amounts may not be safe and harmless.

Kidney disease: People who suffer from kidney disease may not tolerate nickel as well as other people. It is best to avoid nickel supplements if you suffer from kidney disease.

Nickel allergy: People who are allergic to nickel, which includes people who have a history of skin rashes when exposed to nickel-containing jewelry, nickel-containing coins, stainless steel, medical implants or nickel-containing dental instruments, may develop allergic reactions when taking nickel orally. These people should not take nickel supplements.

Interactions

Care should be taken when combining nickel with the following medications:

Need

The nickel requirement depends on individual circumstances and is a maximum of 50 µg per day. Foods rich in nickel are cocoa (chocolate), nuts and pulses.