Nickel is a hard, naturally-occurring silver-white metal, with a chemical symbol of Ni and an atomic number of 28. It is the fifth most common element found on Earth, where it is mostly found in the Earth’s crust and core. It is highly resistant to corrosion and oxidation and can be fully recycled. Nickel is classed as a Class 1A carcinogen, as it is known to show cancer in humans. [1,2]
Nickel is used across multiple industries in varying capacities. It is primarily used in the making of alloys—mainly in stainless steel, but also in other metal alloys. Nickel alloys are used in many applications: from toasters and desalination plants, to turbine blades. It is also used in electroplating and in welding and soldering. Nickel is used in batteries and in many of the U.S. coins, including the nickel, dime and quarter. In Australia, all the silver coins (5c, 10c, 20c and 50c) are made from a copper/nickel alloy.
Routes of Exposure [1,4]
The primary route of exposure to nickel is via inhalation
Occupational exposure is common in workplaces where are mining, smelting, casting, grinding and welding nickel.
The general population are exposed to low levels of nickel in their food, water, air and tobacco smoke.
Nickel-plated materials—such as coins, jewellery and stainless steel utensils and cooking materials—could expose those who are using or wearing them.
Nickel poisoning affects a range of systems including the integumentary and respiratory systems.
Acute Effects 
Severity of symptoms depend on the level and type of exposure.
Skin contact with nickel can result in allergic contact dermatitis.
Acute exposure to the metal could cause asthma, cancer of the nasopharynx and lung, or bronchitis.
Nickel exposure could result in nausea, vomiting, headache, weakness, rash or itching on the hands or forearms, and decreased lung function.
Chronic Effects [1,5]
Nickel is toxic to multiple body systems. Long-term exposure to the metal could result in asthma, nasal septum perforations, rhinitis, sinusitis and chronic bronchitis. It can also cause inflammation and cancers of the lungs, noses and sinuses. The latter most often occurs in people who have breathed in the metal dust, while working in nickel refineries and nickel-processing plants.
~h2First Aid Measures 
- Ingestion: DO NOT INDUCE VOMITING. Immediately contact a medical professional.
- Skin contact: Immediately wash affected area with plenty of water for at least 15 minutes. Remove contaminated clothing; do not re-wear until it has been thoroughly de-contaminated. Immediately contact a healthcare professional.
- Eye contact: Check for and remove contact lenses if easy to do so. Rinse eyes for at least 15 minutes; don’t forget to wash under the eyelids. Immediate medical attention is required.
- Inhaled: Take victim to the nearest fresh air source and monitor their breathing. If they are not breathing (and you are qualified), perform CPR with the aid of a pocket mask or one-way valve. Contact a medical professional immediately.
- General: Never administer anything by mouth to an unconscious, exposed person.
Exposure Controls/Personal Protection 
Engineering controls: Emergency eyewash fountains and safety showers should be accessible in the immediate area of the potential exposure. Ensure there is adequate ventilation. Whenever possible, material should be handled in a laboratory, underneath a fume hood.
- Personal protection: Safety glasses, protective and dustproof clothing, glove, an apron and an appropriate mask. For specifications on PPE, check regulations in your jurisdiction.
The Occupational Safety and Health Administration (OSHA) has set an 8-hour time weighted average (TWA) concentration for nickel of 1mg/m3.
Safe Work Australia has set an 8-hour time TWA for nickel of 1mg/m3.