Metallic nickel is a silvery, hard metal or a gray powder not commonly found in nature. It typically exists as a trace constituent in many different minerals, particularly those containing magnesium and iron. In Canada, nickel is usually found in sulphide ores, especially pentlandite, together with copper, cobalt, gold and silver. Nickel’s properties of corrosion and heat resistance, hardness and strength make it an ideal component of alloys.
Most nickel compounds are green to black in colour, yellow when heated, and dissolve easily in water. There are numerous other synonyms and product names for nickel and its compounds; see HSDB for more information.
Nickel compounds were classified by IARC as Group 1, carcinogenic to humans, with a definite link to human lung, nasal, and paranasal cancer. This evaluation was primarily linked to the nickel compounds containing oxygen and sulphur that are commonly encountered in nickel refining work, but the weight of epidemiological evidence for the carcinogenicity of soluble nickel warranted classification of nickel compounds in general as carcinogenic to humans. In a recent IARC review of Group 1 agents, nickel compounds' Group 1 classification was reaffirmed.
Metallic nickel was classified as Group 2B, possibly carcinogenic to humans, due to insufficient epidemiological evidence in humans. Metallic nickel is a lung carcinogen in rats, however, and also caused local sarcomas after injection in rats and hamsters.
Working with nickel (e.g. in nickel refining or welding) can cause chronic bronchitis and decreased lung function, as well as immunological and renal outcomes. It is not clear if these effects are due entirely to nickel, since exposure to other substances (e.g. cobalt) also occurs in these settings. Nickel exposure is also a very common cause of allergic contact dermatitis. 10-20% of the population reports a reaction, usually from jewellery and other consumer products. Some people who are sensitized to nickel may have asthma that is related to their nickel exposure.
stel = short term exposure limit (15 min. maximum)
i = inhalable fraction
Canadian Environmental Guidelines
Nickel and its compounds were not included in the Canadian government environmental guidelines reviewed.[9-12]
DSL – eight nickel compounds are included (already risk managed)
Schedule 1, paragraph 'a'
Nickel and its compounds were not included in other Canadian government chemical listing reviewed.
Statistics from a large nickel producer, indicate that global nickel consumption in 2007 was distributed as follows: stainless steel production, 61%; nickel-based alloys, 12%; electroplating, 9%; casting and alloy steels, 9%; rechargeable batteries, 4%; coins, 2%; and other, 3%. Pure nickel is also used as a catalyst, in magnets, electrical contacts and electrodes, spark plugs, machinery parts, and surgical and dental prostheses.
Canadian Production and Trade
In 2007, Canada produced 15% of the world’s nickel, second only to Russia. There are 10 nickel producers at 6 different locations in Canada: central Ontario, northern Manitoba, northern Quebec, and Labrador. Further processing occurs in Sudbury, Ontario; Thompson, Manitoba; and Fort Saskatchewan, Alberta. Ontario mines produced 53% of all Canadian nickel in 2006.
Nickel is commonly recycled; in 2007, 47% of nickel used globally in the production of stainless steel was recycled.
Production and Trade
Export: Mainly to China
139 t of ‘nickel ores and concentrates’
Export: Mainly to US, China
88,304 t of ‘unwrought nickel’
Import: Mainly from Australia
20,281 t of 'nickel ores and concentrates'
Import: Mainly from Canada*, Norway
1,962 t of 'unwrought nickel'
Inhalation of particles and fumes and dermal contact are the main routes of occupational exposure. CAREX Canada estimates that approximately 117,000 Canadians are exposed to nickel in their workplace. The largest industrial groups exposed to nickel are commercial and industrial machinery and equipment repair and maintenance, motor vehicle parts manufacturing, and architectural and structural metals manufacturing.
The largest occupational groups exposed to nickel are welders, followed by machine tool operators, and construction millwrights and industrial mechanics. Other important occupations that may be exposed include mechanics, dental technologists, painters and coaters, workers in nickel refineries or nickel processing plants, as well as occupations involving alloy nickel production, stainless steel production, welding, electroplating, grinding and cutting operations.
The primary source of exposure to nickel for most Canadians is food and water. However, nickel is not carcinogenic via ingestion; inhalation exposure is the only pathway relevant to cancer.
Nickel is found naturally in soil and in meteorites. It is also released and transported in the environment from windblown dust and volcanic eruptions. Anthropogenic sources include nickel mining and industries producing alloys or nickel compounds. Oil and coal burning power plants and trash incinerators are additional sources. The type of nickel in the atmosphere depends on the source of emission. CAREX Canada estimates that nickel concentrations in outdoor air (moderate data quality) and indoor air (low data quality) are not likely resulting in elevated risk of cancer.
For more information, see CAREX Canada’s environmental exposure estimates for nickel. Searches of environmental and consumer product databases yielded the following results on current potential for exposure to nickel in Canada:
NPRI and US Household Products Database
Search term: 'nickel and its compounds'
Released into Environment
Petroleum refineries, power generation, nickel refineries, mining and foundries (293 facilities)
Sent to off-site recycling
US Household Products 2013
Electrical grease, batteries, and concrete colourant
Our team has performed a detailed scan of exposure control resources and assembled a compilation of key publications and resources. These are organized by type of exposure (environmental or occupational) and by specificity (general or carcinogen-specific). Please visit our Exposures Reduction Resources page to view.
We also recommend exploring the Prevention Policies Directory, a freely-accessible online tool offering information on policies related to cancer and chronic disease prevention. Providing summaries of the policies and direct access to the policy documents, the Directory allows users to search by carcinogen, risk factor, jurisdiction, geographical location, and document type. To learn more about policies specific to nickel on the Directory, click here. For questions about this resource, please contact Michelle Halligan, from the prevention team at the Canadian Partnership Against Cancer.