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Formaldehyde causes cancer

What you may have heard

Exposure to formaldehyde can cause cancer.

What science tells us

Formaldehyde is a colorless, flammable, strong-smelling chemical that is used in building materials and in the production of many household products. It is used in pressed-wood products (such as plywood and fiberboard), glue, adhesives, permanent-pressed fabrics, paper product coatings, insulation, fungicide, germicide, disinfectant, and as a preservative in mortuaries and medical laboratories. Exposure to formaldehyde mainly occurs by inhaling the gas or absorbing liquids containing formaldehyde through the skin. Short-term health effects of exposure are watery eyes; burning sensations in the eyes, nose, and throat; coughing; wheezing; nausea; and skin irritation. Industrial workers who produce formaldehyde or formaldehyde-containing products, laboratory technicians, healthcare professionals, and mortuary employees may be exposed to higher levels of formaldehyde than the general public.

Epidemiological Evidence

Myeloid leukemia and cancers of the paranasal sinuses, nasal cavity, and nasopharynx are all associated with formaldehyde use(NCI). The general population is exposed to formaldehyde from car exhaust emissions, pressed-wood products in the home, cigarette smoke, unvented field-burning appliances (such as gas stoves, wood-burning stoves, and kerosene heaters) (ACS).

Laboratory Evidence/Supporting Evidence

Studies conducted on rats explain how the inhalation of formaldehyde causes leukemia and nasal cancer. Another study on rats examined the ingestion of formaldehyde which also resulted in the presence of stomach cancer (ACS).

IARC Carcinogen Classification: Group 1 (Carcinogenic to humans).

How to reduce your risk

The Occupational Safety and Health Administration (OSHA) established a federal standard that reduced the amount of formaldehyde to which workers can be exposed over an 8-hour workday from 1 part-per-million (ppm) to 0.75 ppm (NCI). The Environmental Protection Agency (EPA) recommends use of “exterior-grade” pressed-wood products to limit formaldehyde exposure in the home. Formaldehyde levels can also be reduced by ensuring a home has adequate ventilation, moderate temperatures, and reduced humidity levels (NCI).  Vaping/e-cigarettes may contain formaldehyde, so avoiding this exposure may reduce cancer risk.

Bottom line

Formaldehyde is a known human carcinogen. Exposure to formaldehyde should be reduced or avoided entirely when possible.

American Cancer Society (ACS): Known and probable human carcinogens
National Cancer Institute (NCI): Formaldehyde and cancer
National Cancer Institute (NCI): Formaldehyde


Published: June 30, 2021
Verified/updated: August 22, 2022