Metallic nickel is a silvery, hard metal or a gray powder. It is not commonly found in nature. Nickel typically exists as a trace component of 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 hardness, strength, and resistance to corrosion and heat make it an ideal component in alloys.
Most nickel compounds are green to black in colour, turn yellow when heated, and dissolve easily in water. There are numerous other synonyms and product names for nickel and its compounds; see Hazardous Substances Data Bank (HSDB) for more information.
Nickel compounds were classified by the International Agency for Research on Cancer (IARC) as Group 1, carcinogenic to humans, with a definite link to lung, nasal, and paranasal cancer in humans. This evaluation was primarily linked to nickel compounds containing oxygen and sulphur, which are commonly encountered in nickel refining work. However, epidemiological evidence for soluble nickel was conclusive enough to classify nickel compounds in general as carcinogenic to humans. The Group 1 classification for nickel compounds was reaffirmed in the 2012 IARC review of Group 1 agents.
Metallic nickel and alloys were classified as Group 2B, possibly carcinogenic to humans. This classification is based on insufficient epidemiological evidence in humans and sufficient evidence for lung cancer in rats. Metallic nickel also caused local sarcomas after injection in rats and hamsters. Nickel alloys display limited evidence of carcinogenicity in animals.
Working with nickel (e.g. in nickel refining or welding) can cause chronic bronchitis and decreased lung function, as well as immunological and renal effects. 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. An estimated 10-20% of the population reports a reaction to nickel, usually from jewellery and other consumer products. Some people who are sensitized to nickel may have asthma that is related to their exposure.
stel = short term exposure limit (15 min. maximum)
ACGIH = American Conference of Governmental Industrial Hygienists
TLV = threshold limit value
Canadian Environmental Guidelines
Alberta Ambient Air Quality Objectives
1 hour: 6 µg/m3
Annual Average: 0.05 µg/m3
Manitoba Ambient Air Quality Criteria
24 hour: 2 µg/m3 MAC
Ontario Ambient Air Quality Criteria
24 hour (Ni in PM10): 0.1 µg/m3
24 hour (Ni in TSP): 0.2 µg/m3
Annual (Ni in PM10): 0.02 µg/m3
Annual (Ni in TSP): 0.04 µg/m3
µg/m3 = micrograms per cubic metre
MAC = maximum acceptable concentration
PM10 = particles less than 10 micrometers in diameter
TSP = total suspended particulate
Nickel and its compounds were not included in other Canadian government environmental guidelines reviewed.[12,13,14,15]
DSL – eight nickel compounds are included (already risk managed)
Schedule 1, paragraph 'a'
DSL = domestic substance list
CEPA = Canadian Environmental Protection Act
Nickel and its compounds were not included in other Canadian government chemical listing reviewed.
Nickel compounds are used in electroplating, various pigments, and nickel-cadmium batteries. They also act as intermediates in other reactions. The largest use of nickel worldwide is in stainless steel (65% of global usage) and other alloys (20% of usage). Pure nickel is also used as a catalyst and in magnets, electrical contacts and electrodes, spark plugs, machinery parts, and surgical and dental prostheses.
Canadian Production and Trade
In 2014, four Canadian provinces (Manitoba, Newfoundland, Ontario, and Quebec) had active nickel mines. Total production from those mines that year was over 218,000 tonnes, with the largest amount originating from the Sudbury area.
Production and Trade
10,124 t of 'nickel ores and concentrates'
128,678 t of 'unwrought nickel'
12,826 t of 'nickel ores and concentrates'
1,360 t of 'unwrought nickel'
t = tonne
The main routes of occupational exposure to nickel include inhaling particles and fumes, and dermal contact.
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 (working with stainless steel), followed by machine tool operators, construction millwrights, and industrial mechanics. Other occupations where exposure to nickel may take place include mechanics, dental technologists, painters and coaters, and workers in nickel refineries or nickel processing plants. Occupations that involve producing nickel alloy and stainless steel, welding, electroplating, grinding, and cutting operations may be exposed as well.
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 linked 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 that produce 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 emission source. CAREX Canada estimates that nickel concentrations in outdoor air (moderate data quality) and indoor air (low data quality) do not result in an elevated risk of cancer.
Searches of Environment Canada's National Pollutant Release Inventory (NPRI) and the US Household Products Database 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 (268 facilities)
Sent to off-site recycling
t = tonne
US Household Products 2015
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. Click here to learn more about policies specific to nickel in the Directory. For questions about this resource, please contact a member of the Prevention Team at the Canadian Partnership Against Cancer at firstname.lastname@example.org.