Formaldehyde is a flammable and colourless gas with a pungent odour. It may also be referred to as formalin or methanal. There are numerous other synonyms and product names; see the Hazardous Substances Data Bank (HSDB) for more information.
Formaldehyde is classified by the International Agency for Research on Cancer (IARC) as Group 1, carcinogenic to humans, on the basis of sufficient evidence of carcinogenicity in humans and experimental animals. Epidemiological studies reviewed by IARC demonstrated consistently strong evidence that formaldehyde causes nasopharyngeal cancer in humans; strong, but not sufficient evidence that occupational exposure to formaldehyde causes leukemia; and limited evidence that formaldehyde exposure causes sinonasal cancer. A recent IARC review of Group 1 carcinogens reaffirmed this classification, with new, sufficient evidence for leukemia.
Additional health effects of exposure to formaldehyde include respiratory and eye irritation and contact dermatitis.
Agreement Respecting the Great Lakes Basin Ecosystem
Listed as a “Hazardous Polluting Substance”
DSL = domestic substance list
CEPA = Canadian Environmental Protection Act
Formaldehyde was not included in other Canadian government chemical listings reviewed.[17,18]
Formaldehyde is used primarily to produce chemical intermediates (i.e. urea-formaldehyde resins, phenolic resins, etc.) for adhesives and binders in the wood products, pulp and paper, and synthetic vitreous fibre industries. Formaldehyde-based resins are used to make oriented strand board and other wood products in the wood industry. It is also used to produce plastics and coatings, to finish textiles, and to manufacture various industrial chemicals.
As an aqueous solution, formaldehyde is an effective disinfectant and preservative that may be used in hospital wards, pathology labs, and funeral homes (as an embalming fluid). It is also used as a germicide, insecticide, and fungicide. As an antibacterial agent, formaldehyde is found in soaps, shampoos, hair preparations, deodorants, lotions, cosmetics, mouthwash, and nail products.
Canadian Production and Trade
Production and Trade
5,065 t of ‘methanal (formaldehyde)’
5,122 t of ‘methanal (formaldehyde)’
t = tonne
Inhalation is the main route of exposure for formaldehyde. However, lower levels of exposure may occur via dermal absorption or ingestion.
CAREX Canada estimates that approximately 152,000 Canadians are exposed to formaldehyde in their workplaces. Currently, the three most important sources of formaldehyde exposure include decomposition of formaldehyde-containing resins, emissions from solutions (e.g. embalming fluid), and combustion sources (e.g. vehicle exhaust).
Although exposure to formaldehyde has decreased over time, exposure still occurs in a wide variety of occupations and industries. The wood product manufacturing and hospital industries are among the largest exposed industrial groups in Canada. In terms of occupations, the largest groups of workers exposed to formaldehyde are furniture and fixture assemblers.
In wood panel manufacturing, formaldehyde is released when heating adhesives, which can expose press operating and maintenance workers. In furniture manufacturing, formaldehyde is released when preparing and applying varnishes or paints (especially when applied with a spray gun), and drying. Therefore, painters, manual labourers working at dryers, and maintenance workers can also be exposed.
Other occupations with acute exposure to formaldehyde include cooks, embalmers, pathology lab workers, wood, and pulp and paper processing workers. Health care professionals (nurses, dentists, and pharmacists) may also be exposed while using or cleaning up medical products and equipment.[2,20]
Workers involved in producing resins, man-made vitreous fibres, and plastic products are potentially exposed to formaldehyde. Levels are expected to be low, however, because of improved ventilation and the development of resins that release less formaldehyde.
The biggest sources of environmental formaldehyde are combustion and combustion by-products from power plants, incinerators, refineries, wood stoves, kerosene heaters, cigarettes, photochemical oxidation of hydrocarbons and other formaldehyde precursors, and forest fires.[2,20]
Other sources include vent gas and wastewater from formaldehyde production, vehicle exhaust, and off-gassing from formaldehyde-containing products (e.g., fumigants, soil disinfectants, embalming fluid, leather tanning agents, building material resins, wood products and building materials, and resin-treated fabrics and paper).[2,20]
CAREX Canada estimates that formaldehyde levels in outdoor air do not result in an increased risk of cancer (low data quality). However, these estimates show that formaldehyde levels in indoor air do result in an increased risk (low to moderate data quality).
Historically, the use of urea formaldehyde foam insulation (UFFI) resulted in potentially high concentrations of formaldehyde in homes. UFFI was banned in Canada in 1980.
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 formaldehyde in Canada:
NPRI and US Household Products Database
Substance name: ‘Formaldehyde'
Released into Environment
Wood product manufacturing, meat product manufacturing, resin and synthetic rubber and fibre manufacturing, oil and gas extraction (139 facilities)
Sent to off-site recycling
US Household Products 2016
Adhesives, insulations, baby and pet shampoos, hand soap, body wash, aquatic plant fertilizers
t = tonne
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 formaldehyde in the Directory. For questions about this resource, please contact a member of the Prevention Team at the Canadian Partnership Against Cancer at email@example.com.