Formaldehyde is a colourless, flammable, strong-smelling (pickle-like odour) chemical that is present both indoors and outdoors (occurring naturally). Formaldehyde is very volatile, and is gaseous at room temperature. It is released into the air from many products inside the home.
When an item gives off formaldehyde, it is released into the air through a process called off-gassing. High humidity and high temperatures can speed up and increase the release of formaldehyde from products and surfaces. In some spaces such as manufacturing and commercial buildings, formaldehyde vapours may reach dangerously high concentrations.
Indoor levels of formaldehyde should be as low as possible, if you cannot get indoor levels below background amounts (outdoor levels). Our data (thousands of tests from 2009-current), suggests the average level in homes of all types to be between 24-56 ppb.
There are no regulated standards for levels of formaldehyde in your home, although many organisations have developed recommended exposure levels.
EPA finalized a regulation to set limits on how much formaldehyde can be released from composite wood products and establish a program in which independent certifying organizations will verify that composite wood panel producers comply with the limits on formaldehyde releases. This regulation is a move in the proper direction, though it does not address the many other formaldehyde sources within the built environment.
Since formaldehyde has several natural sources (atmospheric chemical processes; combustion; plants, primarily wood, and animals; decomposition of plant and animal material), outdoor levels typically range from a few ppb in rural areas up to ~20 ppb in more urban areas. Indoor air usually has more formaldehyde than outdoor air, typically ranging from ~20 ppb to several hundred ppb depending on the circumstances. The World Health Organization (WHO) recommends formaldehyde in indoor air be kept below 100 µg/m3, or 80 ppb. Wood-based panels produced in the European Union must meet certain formaldehyde emission limits in-line with the EN13986 standard.
Formaldehyde levels are usually higher in summer than winter because of the higher temperature and humidity in the summer months.
Symptomatic irritations can occur with low levels of formaldehyde exposure, especially in people who are sensitive to the chemical compound.
Individuals vary in how they respond to formaldehyde. Some people have a natural allergic sensitivity to airborne formaldehyde and others may develop a sensitivity as a result of overexposure to formaldehyde or underlying health condition. Researchers have found that some individuals with asthma are more vulnerable to the effects of inhaled formaldehyde.
Some people are very sensitive to formaldehyde, whereas others have no reaction to the same level of exposure. High concentrations of formaldehyde can trigger asthma attacks. Formaldehyde is also considered a known human carcinogen (cancer-causing substance), classified as a Hazardous Air Pollutant (HAP) by the EPA.
How are you exposed to Formaldehyde?
The main route of exposure to formaldehyde is by inhalation. The liquid form (formalin) can be absorbed through the skin. People can also be exposed to small amounts by eating foods or drinking liquids containing formaldehyde.
Our bodies produce a small amount of formaldehyde naturally. When exposed to environmental formaldehyde (indoor or outdoor), enzymes in the body break down formaldehyde into formate (formic acid anion). Most inhaled formaldehyde is broken down by the cells lining the mouth, nose, throat, and airways, so that less than a third is absorbed into the blood.
According to the US Consumer Product Safety Commission, formaldehyde is normally present at low levels (less than 0.03 ppm or 30 ppb) in both indoor and outdoor air. Materials containing formaldehyde can release it as a gas or vapor into the air. Automobile exhaust is a major source of formaldehyde in outdoor air.
How can you DECREASE your EXPOSURE?
The best way to reduce your exposure is to avoid products that contain formaldehyde, and to not allow cigarette smoking in your home. Look for products that are labeled as ‘no’ or ‘low’ VOC or formaldehyde. When purchasing pressed wood products for your home, look for those that are labeled as compliant with the European E1 standard for formaldehyde emissions.
Furniture and pressed-wood board made with laminated surfaces release less formaldehyde and other VOCs. Where possible, use non-toxic alternatives to formaldehyde-containing products such as glue and adhesives.
Open windows or use exhaust fans to blow indoor air out and bring fresh air in. Make sure any combustion appliance has a separate exhaust to the outdoors. Remember to ventilate indoor spaces when using cleaners, cosmetic products like nail polish remover or most paints.
Many consumer products that emit formaldehyde, such as medium-density fibreboard (MDF), plywood, and particle board, release the highest concentrations when they are new. Open any packaging and air the product out before installing or bringing indoors.
Not smoking and prohibiting smoking indoors can reduce exposure to formaldehyde. Secondhand smoke contains many chemicals in addition to formaldehyde that can harm health.
Many permanent press or “Wrinkle-Free” clothing contains and emits formaldehyde. Although convenient, the exposure is greater for both inhalation and dermal routes. Simple laundering before wearing will help to reduce exposure.
Those who are concerned about formaldehyde exposure from personal care products and cosmetics can avoid using products that contain or release formaldehyde. Due to dermal exposure and close proximity to breathing zone, the impact of this formaldehyde exposure route should not be ignored.