Volatile organic compounds (VOCs) are noxious air pollutants, ten times more concentrated indoors than outdoors, with thousands of household products releasing them every day. Air purifiers are an effective way to remove contaminants from our air, and some types may be able to remove VOCs.
Air purifiers with activated carbon filters are most effective at removing volatile organic compounds (VOCs). The activated carbon removes VOCs from the air by adsorption, a process where VOCs, such as formaldehyde, adhere to the surface of the carbon filter. HEPA filters, air ionizers, and UV-C light filters are not effective in removing VOCs from indoor air.
In this post, we’ll explain VOCs, their sources, their health impacts, and the types of air purifiers that can or cannot remove indoor VOCs. We’ll also list four of the best air purifiers for removing VOCs.
What are Volatile Organic Compounds?
Volatile organic compounds are chemical compounds that evaporate quickly under normal indoor atmospheric pressure and temperature. The World Health Organization (WHO) classifies indoor organic pollutants as:
- Semi-volatile organic compounds (SVOCs)
- Volatile organic compounds (VOCs)
- Very volatile organic compounds (VVOCs)
Semivolatile organic compounds (SVOCs) are abundant in indoor air and are of great concern due to their potential adverse health effects. Examples of SVOCs include pesticides, such as DDT, and many fire retardants.
Volatile organic compounds (VOCs) constitute a small percentage of total indoor air and most of them are found mixed in liquids or solids or on surfaces such as building materials and furniture. Some of the most well-known VOCs include asbestos and radon.
Very volatile organic compounds (VOCs) are unstable compounds entirely found as gases in the air, such as butane, propane and formaldehyde, and are difficult to measure.
Common Indoors VOCs
The typical household VOCs are:
- Formaldehyde
- Benzene
- Ethylene glycol
- 1,3-butadiene
- Methylene chloride
- Xylene
- Tetrachloroethylene
- Toluene
Sources of VOCs
According to the EPA, common sources of household VOCs are:
- Building materials such as paint, caulks, adhesives, varnishes, vinyl flooring, upholstery, foam
- VOCs from various activities such as smoking, cooking, dry cleaning, photocopiers, and burning wood
- Home and Personal Care products such as cosmetics, aerosol sprays, fuel oil, cleaning products, gasoline, pesticides, automotive products, glues, and permanent markers
Health effects of VOCs
The health effects of VOCs vary depending on the nature of the chemicals, the concentration and the length of exposure. It is also important to note that most health-related impacts of VOCs are based on the studies of single chemicals, rather than a combination of chemicals.
People with allergies and respiratory disorders are at a higher risk of negative health effects after exposure to VOCs, even at low concentrations. For detailed toxicological profiles of individual VOCs, please visit the Agency for Toxic Substances and Disease Registry portal.
The American Lung Association advises that some VOCs can even cause cancer. However, all VOCs don’t have the same adverse health effects.
Symptoms of VOCs Exposure
The most obvious symptoms of VOC exposure include:
- Headache
- Nausea
- Visual impairments
- Eyes irritation
- Respiratory tract irritation
- Loss of coordination
- Damage to kidney and liver
Some lesser-known key signs associated with exposure to VOCs include:
- Epistaxis
- Dyspnea
- Fatigue
- Emesis
- Skin allergy
- Conjunctival irritation
- nose and throat discomfort
- Reduction in serum cholinesterase levels
Why you need to remove VOCs
According to the EPA, the levels of many contaminants in indoor environments are 2 to 5 times higher than outdoors, even worse is the concentration of VOCs – which are up to 10 times higher. A staggering number when you think of the health implications.
In fact, research shows that the indoor concentration of VOCs largely varies from 16.6–8150 μg m−3, and their prolonged exposure can raise serious health problems, particularly among people with sensitivities.
The removal of VOCs from our indoor environment is a pressing concern and one we should all be thinking about.
How air purifiers remove VOCs
Some air purifiers can remove volatile organic compounds. However, there are some types that can actually make a VOC problem worse. Air purifiers with activated carbon filters are the most efficient and chemical reaction-free means of removing VOCs from the air.
Activated Carbon Filters
Activated carbon filters contain granular activated carbon with a large surface area and tiny pores that collect and remove VOCs and small particles from the air. These filters remove VOCs through adsorption rather than absorption, which means that air pollutants become attached to the surface of activated carbon molecules and are removed from the air.
In air purifiers with an activated carbon filter, the air enters the purifying device, passes through the activated carbon filter, the small particles, and VOCs undergo adsorption, and the purified air is returned to the atmosphere. The activated carbon is inserted into the purifier, often with another filter, such as a HEPA filter.
HEPA Filters
Air purifiers with HEPA (High-Efficiency Particulate Air) filters can remove 99.97% of air pollutants (as small as 0.3 microns), including dust, pet dander, mold, pollen, and bacteria.
However, they are ineffective against VOCs.
VOCs are much smaller gas molecules and are able to easily pass through HEPA filters. In fact, most VOC molecules are thousands of times smaller than the HEPA filter’s trapping capacity.
UV Light Filters
Air purifiers with UV light filters use short-wave ultraviolet light (UV-C light) to kill various airborne pathogens and microbes, including bacteria, viruses, and molds.
The air is forced into the purifying device and passed through a UV lamp that uses radiation for germicidal action, and the disinfected air is distributed back into the atmosphere. UV-C air purifiers are ineffective against VOCs.
Stand-alone UV-C air purifiers are uncommon because they require an additional filtration system to improve indoor air quality.
Air Ionizers
An air ionizer emits negatively charged particles that stick to large air pollutants and weigh them down. This causes the pollutants to settle onto the ground and surrounding furniture, leaving purified air for breathing, but they have no effect on small particles and gases, including VOCs.
How to choose the right air purifier
To choose the best air purifiers effective against VOCs, you need to consider the following:
Filter Type: Choose a stand-alone purifier with an activated carbon air filter or one that combines an activated carbon with another filter (e.g., True HEPA filter).
Coverage Area: Ensure the coverage capacity of the air purifier is suitable for the size of your space. An air purifier that is too small for your room will be unable to effectively remove VOCs.
Best Air Purifiers for Removing VOCs
Here’s four of the best air purifiers for removing indoor VOCs (available on Amazon).
1. Afloia Kilo Air Purifier
The Afloia’s Kilo air purifier features a 3-in-1 purification system with a prefilter, a HEPA filter, and an activated carbon filter to efficiently remove 99.99% of air pollutants as small as 0.3 microns.
The activated carbon filter removes VOCs.
2. PureZone Air Purifier
Pure Enrichment’s PureZone air purifier comes with a three-stage filtration system with an activated carbon filter, true HEPA filter, and UV-C light for efficiently removing 99.97% of air contaminants as small as 0.3 microns, including VOCs.
This model can cover spaces of up to 200 sq. ft.
3. Alen BreatheSmart Classic Air Purifier
The Alen BreatheSmart Classic Air Purifier comes with a ‘FreshPlus’ filter containing the True HEPA filter with 0.6 pounds of activated carbon to efficiently remove VOCs, allergens, smoke, and other toxins larger than 0.1 microns.
These air purifiers can cover large areas up to 1100 sq. ft every 30 minutes.
4. hOmeLabs True HEPA Air Purifier
The hOmeLabs True HEPA Air Purifier removes 99.97% of airborne particles as small as 0.3 microns.
Three stages of purification, including a pre-filter, True HEPA filter and activated carbon filter ensure both large and dust sized lead particles are efficiently removed along with other particulate contaminants and VOCs.
Each HEPA filter provides almost 3 months or 2100 hours of pure air when set on the low to medium fan mode.
How can I reduce the VOCs in my house?
To reduce VOCs in your home the EPA recommends:
- Increasing the ventilation when using products that can emit VOCs.
- Always try to meet the label precautions.
- Reduce pesticide usage by using integrated pest management techniques.
- Avoid mixing household care products with other daily use products
- Don’t store unused paints or varnish material near the living room or bedroom.
- Buy VOC emitting products in limited quantities only or as required so that you don’t have to store the leftovers in your home.
- Reduce formaldehyde, the most common VOC, by identifying and measuring its level. Try to get rid of its source if possible; if not, use sealant on all exposed surfaces to reduce direct exposure.
Air purifiers can effectively remove formaldehyde – this article has more information on formaldehyde.
- Reduce benzene, a potential carcinogen, by providing ventilation and plenty of fresh air during painting, eliminating smoke inside the home, and discarding fuel and paint supplies that are not to be used readily.
- Minimize exposure to perchloroethylene emissions from newly dry-cleaned materials. To do this, avoid accepting improperly dried clothes with strong chemical odors or try a different cleaner.
How long do VOCs stay in air?
VOCs are often the result of ongoing off-gassing from a product, rather than from a single event. These products emit VOCs continuously until off-gassing is complete. This process varies depending on the material, for example, pressed-wood products can release formaldehyde (a VOC) for 10 months into the surrounding air.
However, there is no precise expert information on how long VOCs remain in the air. According to the EPA, all VOCs are released during the use of products responsible for off-gassing and, to a lesser degree, when stored.
In fact, the EPA’s Total Exposure Assessment Methodology (TEAM) Study, showed elevated concentrations of organic compounds persists long in the air even after the activity has been completed.
This means VOCs can remain in the air throughout a lengthy period of time. Air purification and ventilation can help reduce and remove the VOC concentration in the air.
Should I Close the Door When Using an Air Purifier?
Doors should be closed when using an air purifier. To avoid further air contamination, close the doors and windows. Your air purifier will then effectively improve air quality by removing air pollutants, including VOCs in a short time.
