The smells we associate with newness and cleanliness — a fresh coat of paint, a new car, lemon-scented disinfectant — are not as harmless as they may seem. These odors are caused by the release of gases called volatile organic compounds (VOCs), and they come from more sources than you might expect. When these gases build up in indoor air, some of them can contribute to a wide range of health problems. Here, we dig into what VOCs are, where they can come from, and what you can do to remove them from your home.
What are volatile organic compounds?
Volatile organic compounds are a group of carbon-containing gases that can contribute to indoor air pollution. VOCs are often used in the manufacturing of household products, such as furniture, carpets and electronics. They can also be found in some cleaning supplies, paints, adhesives and other liquids. Some examples of VOCs commonly found in homes are formaldehyde, toluene, benzene, and tetrachloroethylene.
During the manufacturing process, VOCs often start out as solids or liquids. However, they have a high vapor pressure, meaning that they evaporate easily at room temperature. This evaporation is called off-gassing, and it represents a significant source of VOCs in the home.
Throughout the life of a product, the VOCs used during its manufacture will off-gas and affect the indoor air quality. This off-gassing can sometimes — but not always ? cause odors, such as the smell of a new piece of furniture, fresh carpeting or new electronics. However, VOC’s odor, or lack thereof, does not indicate its potential to cause harmful health effects.
Why should you be concerned about VOCs?
Though VOCs can be found outdoors, they are typically present at higher concentrations in indoor air. According to the Environmental Protection Agency (EPA), indoor levels of certain VOCs can be around two to five times the amount you would find in outdoor air. If you are using products that contain VOCs, such as paints and cleaning products, airborne concentrations can increase exponentially and remain elevated for long after you have stopped using the product.
VOCs are an air quality concern because of their potential to cause adverse health effects. The severity of these health effects depends on the length of exposure, the type of VOC, and the concentration of harmful VOCs in the air. For this reason, the EPA recommends taking steps to reduce the presence of VOCs in your home.
When inhaled, VOC molecules can enter the lungs, bloodstream and tissue within the body. Many different health effects are associated with VOC exposure, ranging from short-term irritation to long-term severe health problems. Children, older adults and individuals with respiratory conditions are the most at risk for adverse effects from inhaling VOCs. Symptoms of VOC exposure can include:
- Irritation or discomfort in the eyes, nose, or throat;
- Difficulty breathing;
- Nausea or vomiting;
- Allergic skin reactions;
Several VOCs are known or suspected carcinogens (cancer-causing substances). Many common household VOCs have been linked to cancer, such as:
Where do VOCs come from?
The best way to lower the concentration of VOCs in your home is to remove their source. However, finding and removing sources of VOCs is not always easy. As discussed above, one of the main ways that VOCs enter your home is through a process called off-gassing. During off-gassing, the VOCs used to make certain items start to evaporate and become a part of your indoor air.
Common sources of household product off-gassing include mattresses, furniture made from pressed wood (such as plywood or particle board), upholstery, curtains, carpeting, vinyl flooring, computers and printers.
Though it may not be practical to remove all the above VOC-emitting products from your home, there are a couple of steps you can take to reduce their effects on indoor air quality. First, you can allow new furniture to air out in a garage or shed before bringing it into your home. Second, you can increase ventilation in rooms with new furniture and flooring. Opening windows and doors can help bring in fresh air, and running exhaust fans can help vent some high-VOC air to the outdoors.
(Note: Secondhand furniture will typically cause less air pollution than new furniture because it has had more time to off-gas the VOCs from when it was made. If you are looking for new furniture, you can opt for solid wood pieces with low-VOC finishings and display pieces that have had time to air out in the store).
VOCs can also come from the use of other household items, such as:
- Cleaning chemicals;
- Paints and varnishes;
- Air fresheners;
- Permanent markers and other craft supplies;
- Nail polish remover;
- Personal care products.
These products can cause a significant increase in indoor VOC concentrations when in use. However, in some cases, they can still off-gas fumes even when they are stored in sealed containers. To help reduce the VOCs you bring into your home, try to buy as little as possible when it comes to high-VOC products like paint, adhesives, caulks and solvents.
If you have some of these products left over between uses, store them in a shed or detached garage if possible. This can help decrease the VOCs that leak into your home. Also, try to keep unused chemicals from sitting in your garage or house. Instead, when you are finished with a project, dispose of any leftover materials according to your local hazardous waste disposal guidelines.
Another way to remove VOCs at the source is to choose low- or no-VOC options when shopping for household items. To learn more about the VOC content of different products, you can search for them in the Consumer Product Information Database (CPID).
Do air purifiers work on VOCs?
While source control is the best way to lower the presence of VOCs in your home, it is virtually impossible to rid your home of all VOCs. Increasing the ventilation in your home by opening windows and doors can have a significant positive impact on air quality, especially during high-VOC activities such as painting or laying down a new carpet. However, it may not always be the best way to reduce VOC concentrations in your home.
For example, opening your windows during high-pollen days may bring allergens into your home that were not there before. Plus, precipitation and extreme outdoor temperatures may sometimes make it impractical to keep windows open. Though helpful, increasing ventilation is often only a temporary solution.
Air purifiers, on the other hand, can be used all day and night. In fact, it is recommended that you keep your air purifier on twenty-four-seven. Air purifiers work best when they can continuously turn over the air in a room, removing contaminants as they increase air circulation. However, not all air purifiers are equipped to capture airborne VOCs. In fact, there are only two types of air purification technologies that can handle VOCs: carbon filters and Photo Electrochemical Oxidation (PECO).
Carbon filters and VOCs
Air purifiers with carbon filters are designed to remove gaseous pollutants from indoor air. These filters use a process called adsorption to capture VOCs and other harmful gases. As air passes through the filter, gaseous pollutants stick to the outside of the carbon particles in the adsorption area. Typically, the carbon in the adsorption bed has a lattice structure with many tiny open holes that increase the surface area that VOCs can stick to.
As the filter removes more pollutants from the air, the available surface area on the adsorption bed decreases. When the filter becomes saturated with pollutants, it is no longer effective at removing them from the air. Furthermore, the air passing through the filter may dislodge some of the trapped pollutants and reintroduce them into the air. To help avoid this, you should change your carbon filters regularly according to the manufacturer’s recommendations.
(Note: VOCs are not the only type of pollutant that can be found in indoor air. While carbon filters may trap gaseous pollutants, their lattice structure makes them ineffective against other types of pollution, including dust, allergens, and mold spores).
PECO technology and VOCs
PECO air purification technology uses a light-activated catalyst to destroy VOCs at the molecular level. When organic compounds in the air (such as VOCs) pass through the PECO filter, they come into contact with the catalyst and cause it to create powerful chemicals called hydroxyl radicals. These hydroxyl radicals then react with VOCs in the air to destroy them at the molecular level. Because PECO technology destroys VOCs instead of merely trapping them, there is no chance of them breaking free from the filter and being released back into the air.
The ability of PECO technology to remove VOCs from the air has been proven in laboratory settings on multiple occasions. Recently, Intertek, a Nationally Recognized Testing Laboratory (NRTL), performed an independent lab test on Molekule Air and found that it effectively removed the VOCs formaldehyde, toluene and limonene from the air. The same lab tested both Molekule Air Mini and Air Pro and found similar results.
Unlike carbon filters, Molekule devices can handle more than just gaseous pollutants. The above laboratory tests also verified their ability to remove particle pollution from the air, including smoke, dust and pollen.
With the wide range of products that can contribute to VOC concentrations in your home, it may seem like VOCs are an unavoidable part of life. While that may be partly true, it is still possible to keep them from building up to harmful levels in your home. By removing sources of toxic air pollutants and taking steps to protect your indoor air quality, you can reduce household VOC exposure for you and your loved ones.