Health and Environment

Hazards

Because it is highly reactive, water soluble and rapidly metabolized, people may experience toxic, irritating and sensitizing effects at the site of contact.  Inhaled formaldehyde is readily absorbed by the upper respiratory tract and is rapidly metabolized by almost every cell in the body.

Acute (Short-Term) Health Effects

  • Acute exposure to formaldehyde causes throat, nose, eye and skin irritation. People with asthma may be more sensitive to the effects of inhaled formaldehyde.
  • Skin contact results in severe irritation and burns and some formaldehyde may pass through the skin.
  • When inhaled, formaldehyde causes narrowing of the bronchi resulting in coughing, wheezing, chest pains, and bronchitis. At high levels, formaldehyde can cause fluid build-up in the lungs and can result in death.

Chronic (Long-Term) Health Effects

  • In 2006, IARC changed the formaldehyde classification from Group 2A (probable human carcinogen) to Group 1 (carcinogenic to humans). This classification was based on “sufficient evidence of nasopharyngeal cancer in humans, strong but not sufficient evidence of leukemia in humans, and limited evidence of sinonasal cancer in humans.” In 2009, IARC reaffirmed the Group 1 classification and also concluded that there was sufficient evidence of leukemia in humans.
  • Studies conducted by the National Cancer Institute (NCI) found an increased risk of lung and nasopharyngeal cancers and leukemia among funeral industry workers, such as embalmers in mortuaries, from occupational exposure to formaldehyde.
  • The Association of Occupational and Environmental Clinics (AOEC) lists formaldehyde as an occupational asthmagen. The Collaborative on Health and the Environment (CHE) states that there is good evidence for an association between formaldehyde and the onset of allergic asthma. Studies indicate that repeated prolonged exposures may result in sensitization of the individual, who are then more likely to experience contact dermatitis and asthma attacks.
  • Formaldehyde exposure has been associated with reproductive effects such as spontaneous abortions, congenital malformations, low birth weights, infertility and endometriosis.

Exposure Routes

The primary route of exposure is through inhalation.  Occupational and consumer exposure can, however, also include dermal exposure, especially to formaldehyde in solution.

Worker Health

The primary sources of occupational exposure to formaldehyde are:

  • Industrial production (resins, molding compounds, fertilizer, paper, wood products, furniture, laminates, plastics, pesticides, chemical manufacture, rubber, leather tanning, iron foundries, photographic film, textiles, scientific supply and cosmetics)
  • Agriculture (sugar production, grain and seed preservation)
  • Oil extraction (well-drilling fluids)
  • Funerary work (embalming fluid)
  • Hospitals, laboratories and schools (preserved tissue and specimens)
  • Construction (manufactured wood products)
  • Transportation and energy (product of combustion)
  • Beauty salons (sanitizers, hair products and cosmetics)

Public Health

  • A widely used chemical, especially in building products, and a byproduct of combustion, formaldehyde is ubiquitous in urban areas and buildings at low levels. Formaldehyde is regarded as a common indoor air contaminant.  Contained in many construction products and home furnishings (including plywood, particleboard, medium density fiberboard, oriented strand board, insulation, carpets, other flooring, and related adhesives), unreacted formaldehyde off-gases into the air. Off-gassing is highest for new products and decreases over time. Tobacco smoke is another source of formaldehyde exposure in indoor environments.
  • Manufacturing facilities and combustion sources are major sources of formaldehyde in outdoor air.  Additional sources include automobiles, power plants, incinerators, and refineries which create formaldehyde as a byproduct of incomplete combustion.
  • Formaldehyde is formed when sunlight breaks down ozone and nitrogen oxides, and is therefore found in smog in the lower atmosphere.
  • Consumer products such as antiseptics, medicines, cosmetics, hair care products, permanent-press clothing, fabric softeners, shoe-care agents, carpet cleaners, glues and adhesives, lacquers, paper and plastics can contain formaldehyde.

Environmental Fate

Formaldehyde is a natural component of the environment and the human body.  It biodegrades readily in air, water and soil under both aerobic and anaerobic conditions.  In the air, formaldehyde breaks down in sunlight to form carbon monoxide and formic acids, a component of acid rain.  It is not commonly found in drinking water and only in limited quantities in foods such as cheeses and grains where it occurs naturally and is also added to kill pathogens.  Formaldehyde is not bioaccumulative.

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