Indoor Air

TSCA Assistance Line

For further information on 

formaldehyde and consumer products, 

call the EPA Toxic Substance Control 

Act (TSCA) Assistance Line (202) 

554-1404.

Formaldehyde

Formaldehyde is an important chemical used widely by industry to manufacture building materials 

and numerous household products. It is also a by-product of combustion and certain other natural 

processes. Thus, it may be present in substantial concentrations both indoors and outdoors.

Sources of formaldehyde in the home include building materials, smoking, household products, 

and the use of un-vented, fuel-burning appliances, like gas stoves or kerosene space heaters. 

Formaldehyde, by itself or in combination with other chemicals, serves a number of purposes in 

manufactured products. For example, it is used to add permanent-press qualities to clothing and 

draperies, as a component of glues and adhesives, and as a preservative in some paints and 

coating products.

In homes, the most significant sources of formaldehyde 

are likely to be pressed wood products made using 

adhesives that contain urea-formaldehyde (UF) resins. 

Pressed wood products made for indoor use include: 

particleboard (used as sub-flooring and shelving and in 

cabinetry and furniture); hardwood plywood paneling 

(used for decorative wall covering and used in cabinets 

and furniture); and medium density fiberboard (used for 

drawer fronts, cabinets, and furniture tops). Medium 

density fiberboard contains a higher resin-to-wood ratio than any other UF pressed wood product 

and is generally recognized as being the highest formaldehyde-emitting pressed wood product.

Other pressed wood products, such as softwood plywood and flake or oriented strand board, are 

produced for exterior construction use and contain the dark, or red/black-colored phenolformaldehyde (PF) resin. Although formaldehyde is present in both types of resins, pressed 

woods that contain PF resin generally emit formaldehyde at considerably lower rates than those 

containing UF resin.

Contents

• Background

• Sources of Formaldehyde

• Health Effects

• Levels in Homes

• Steps to Reduce Exposure

• Additional Resources

• Proposed Rulemaking: Formaldehyde Emissions from Pressed Wood Products

Background

Since 1985, the Department of Housing and Urban Development (HUD) has permitted only the 

use of plywood and particleboard that conform to specified formaldehyde emission limits in the 

construction of prefabricated and mobile homes. In the past, some of these homes had elevated 

levels of formaldehyde because of the large amount of high-emitting pressed wood products used 

in their construction and because of their relatively small interior space.

The rate at which products like pressed wood or textiles release formaldehyde can change. 

Formaldehyde emissions will generally decrease as products age. When the products are new, 

high indoor temperatures or humidity can cause increased release of formaldehyde from these 

products.

During the 1970s, many homeowners had urea-formaldehyde foam insulation (UFFI) installed in 

the wall cavities of their homes as an energy conservation measure. However, many of these 

homes were found to have relatively high indoor concentrations of formaldehyde soon after the 

UFFI installation. Few homes are now being insulated with this product. Studies show that 

formaldehyde emissions from UFFI decline with time; therefore, homes in which UFFI was 

installed many years ago are unlikely to have high levels of formaldehyde now.

Sources of Formaldehyde

Pressed wood products (hardwood plywood wall paneling, particleboard, fiberboard) and furniture 

made with these pressed wood products. Urea-formaldehyde foam insulation (UFFI). Combustion 

sources and environmental tobacco smoke. Durable press drapes, other textiles, and glues.

Basic Information on Pollutants 

and Sources of Indoor Air 

Pollution

• Asbestos

• Biological Pollutants

• Carbon Monoxide (CO)

• Formaldehyde

• Lead (Pb)

• Nitrogen Dioxide (NO2)

• Pesticides

• Radon (Rn)

• Respirable Particles

Secondhand Smoke/ 

Environmental Tobacco Smoke

•

Stoves, Heaters, Fireplaces, 

and Chimneys

•

Volatile Organic Compounds 

(VOCs)

•

Proposed Rulemaking

Formaldehyde Emissions from Pressed 

Wood Products

EPA's Office of Chemical Safety and 

Pollution Prevention will issue rules to 

implement the 2010 Formaldehyde 

Standards for Composite Wood Products 

Act. Read more at 

www.epa.gov/opptintr/chemtest/...

Read "Care for Your Air: A Guide to 

Indoor Air Quality" 

An Introduction to Indoor Air Quality (IAQ)

Formaldehyde | Indoor Air Quality | US EPA Page 1 of 3

http://www.epa.gov/iaq/formalde.html 9/22/2011
Health Effects

Formaldehyde, a colorless, pungent-smelling gas, can cause watery eyes, burning sensations in 

the eyes and throat, nausea, and difficulty in breathing in some humans exposed at elevated 

levels (above 0.1 parts per million). High concentrations may trigger attacks in people with 

asthma. There is evidence that some people can develop a sensitivity to formaldehyde. It has 

also been shown to cause cancer in animals and may cause cancer in humans. Health effects 

include eye, nose, and throat irritation; wheezing and coughing; fatigue; skin rash; severe allergic 

reactions. May cause cancer. May also cause other effects listed under "organic gases." 

EPA's Integrated Risk Information System profile on Formaldehyde: 

www.epa.gov/iris/subst/0419.htm

•

Levels in Homes

Average concentrations in older homes without UFFI are generally well below 0.1 (ppm). In 

homes with significant amounts of new pressed wood products, levels can be greater than 0.3 

ppm.

Steps to Reduce Exposure

Use "exterior-grade" pressed wood products (lower-emitting because they contain 

phenol resins, not urea resins).

•

Use air conditioning and dehumidifiers to maintain moderate temperature and reduce 

humidity levels.

•

Increase ventilation, particularly after bringing new sources of formaldehyde into the 

home.

•

Ask about the formaldehyde content of pressed wood products, including building materials, 

cabinetry, and furniture before you purchase them.

If you experience adverse reactions to formaldehyde, you may want to avoid the use of 

pressed wood products and other formaldehyde-emitting goods. Even if you do not 

experience such reactions, you may wish to reduce your exposure as much as possible by 

purchasing exterior-grade products, which emit less formaldehyde. 

For further information on formaldehyde and consumer products, call the EPA 

Toxic Substance Control Act (TSCA) assistance line (202) 554-1404

•

Some studies suggest that coating pressed wood products with polyurethane may reduce 

formaldehyde emissions for some period of time. To be effective, any such coating must 

cover all surfaces and edges and remain intact. Increase the ventilation and carefully follow 

the manufacturer instructions while applying these coatings. (If you are sensitive to 

formaldehyde, check the label contents before purchasing coating products to avoid buying 

products that contain formaldehyde, as they will emit the chemical for a short time after 

application.)

Maintain moderate temperature and humidity levels and provide adequate ventilation.

The rate at which formaldehyde is released is accelerated by heat and may also depend 

somewhat on the humidity level. Therefore, the use of dehumidifiers and air conditioning to 

control humidity and to maintain a moderate temperature can help reduce formaldehyde 

emissions. (Drain and clean dehumidifier collection trays frequently so that they do not 

become a breeding ground for microorganisms.) Increasing the rate of ventilation in your 

home will also help in reducing formaldehyde levels.

Additional Resources

Proposed Rulemaking: Formaldehyde Emissions from Pressed Wood Products

On July 7, 2010, President Obama signed the Formaldehyde Standards for Composite 

Wood Products Act (PDF, 9 pp., 135 K, about PDF) into law. This legislation, which adds a 

Title VI to TSCA, establishes limits for formaldehyde emissions from composite wood 

products: hardwood plywood, medium-density fiberboard, and particleboard. The national 

emission standards in the Act mirror standards previously established by the California Air 

Resources Board for products sold, offered for sale, supplied, used or manufactured for 

sale in California. Congress directs EPA to promulgate final regulations implementing the 

Act by January 1, 2013. Learn more at www.epa.gov/opptintr/chemtest/formaldehyde/ .

An Update on Formaldehyde: 1997 Revision (CPSC document #725)

Formaldehyde | Indoor Air Quality | US EPA Page 2 of 3

http://www.epa.gov/iaq/formalde.html 9/22/2011
Last updated on Tuesday, February 15, 2011

http://www.epa.gov/iaq/formalde.html

This booklet to tell you about formaldehyde found in the indoor air. This booklet tells you 

where you may come in contact with formaldehyde, how it may affect your health, and how 

you might reduce your exposure to formaldehyde.

• HTML | PDF (12 pp., 37 K, )

• CPSC Website

ToxFAQsTM for Formaldehyde (Formaldehido) (June 1999) U.S. Dept. of Health and Human 

Services, Agency for Toxic Substances and Disease Registry (ATSDR) 

www.atsdr.cdc.gov/tfacts111.html

Safety and Health Topics: Formaldehyde U.S. Dept. of Labor, Occupational Safety and Health 

Administration (OSHA) www.osha.gov/SLTC/formaldehyde/

American Lung Association www.lungusa.org Search "formaldehyde" for 

resources

Asthma

Mold

Radon

IAQ Tools for Schools

Indoor airPLUS Program

IAQ Design Tools for Schools

Smoke-free Homes and Cars

IAQ Tribal Partners Program

Partnership for Clean Indoor Air

Carbon Monoxide

Floods

CIAQ

Ice Arenas

Air Cleaners

www.flu.gov

Formaldehyde | Indoor Air Quality | US EPA Page 3 of 3

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