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What is it?

Formaldehyde is a colorless, flammable gas or liquid. It is naturally produced in small, harmless amounts in the human body.

Formaldehyde is released into the air by burning fossil fuels such as wood, kerosene, or natural gas; from vehicle exhaust; and from smoking tobacco products.

Formaldehyde is used as a tissue preservative in medical laboratories and as an embalming fluid in mortuaries. It is used as a preservative in some foods, and is in some cosmetics, cleaning liquids, paints and varnishes, medicines, permanent press fabrics, carpet cleaners, and wood products.

See also: Factories Healthcare Services Homes Air Pollution Brownfield Asthma and other Lung Diseases Cancer

Where is Formaldehyde found?

  • Consumer products – cigarettes, cosmetics, dishwashing liquids, medicines, carpet cleaners, and wood products
  • Food – some dried foods, cheese, preserved fish
  • Air – cigarette smoke, secondhand smoke, emissions from burning fuels, and vehicle exhaust

How can I be exposed to Formaldehyde?

Formaldehyde commonly enter(s) the body through:

Ingestion (swallowing)
  • Swallowing food that contains formaldehyde
Inhalation (breathing)
  • Smoking cigarettes; breathing cigarette smoke, secondhand smoke, vehicle exhaust, fuel emissions, or emissions from paints and carpets
Skin contact
  • Touching formaldehyde or products that contain formaldehyde

What happens when I am exposed to Formaldehyde?

Exposure to breathing formaldehyde can cause:

  • Irritation of the nose, eyes, and throat
  • Neurological effects
  • Headache
  • Nausea
  • Increased risk of asthma and allergies

Skin contact with formaldehyde can cause:

  • Skin irritation and eczema

Swallowing formaldehyde can cause:

  • Gastrointestinal irritation


  • Long-term exposure to formaldehyde can cause:
  • Cancer
  • Bronchitis
  • Shortness of breath

Who is at risk for exposure to Formaldehyde?

  • Consumers
    • Some consumer products and foods contain formaldehyde. Certain wood products and paints give off formaldehyde at low levels.
  • Cigarette smokers
    • Cigarette smoke and secondhand smoke contain formaldehyde.

Reduce your risk

If you think your health has been affected by exposure to formaldehyde, contact your health care professional. 

Always wash your hands thoroughly after handling chemicals. For poisoning emergencies or questions about possible poisons, please contact your local poison control center at 1-800-222-1222.

  • Do you, or does anyone in your household, smoke tobacco products?
  • Do you use a fireplace or wood-burning appliances?
  • How frequently are you exposed to vehicle exhaust or gas stations?
  • Do you live near a busy highway?
  • Open windows and use fans to bring fresh air indoors regularly, especially after bringing new sources of formaldehyde into the home.
  • Increase ventilation during painting projects. Use low-emitting paints.
  • If you smoke, quit. Avoid secondhand smoke.
  • Limit your time near idling cars, trucks, or buses.
  • Do not use unvented heaters.
  • Clean chimneys and wood-burning appliances.
  • Buy solid wood furniture or be sure unfinished manufactured wood surfaces and pressed wood products are sealed.
  • Let new furnishings “off-gas” before bringing them indoors.
  • Wash new permanent press clothing before wearing it.
  • Don’t let children play near gas stations, idling cars, or busy highways.
  • Keep children away from products that may contain formaldehyde.
National Library of Medicine Resources and Databases
Additional Resources
  • Formaldehyde. ToxFAQs (Agency for Toxic Substances and Disease Registry)

    Factsheet with answers to most frequently asked questions about formaldehyde exposure, and its effect on human health, developed by a federal public health agency that protects communities from harmful health effects related to exposure to natural and man-made hazardous substances.

  • Formaldehyde and Cancer Risk (National Cancer Institute)

    Information on formaldehyde exposure and associated health risks, including developing research on the relationship between formaldehyde exposure and cancer, and links to relevant organizations.

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