Air purifiers are designed to remove particulate matter from indoor air. They have become a standard recommendation for people with allergies, asthma, and rhinitis.
There is considerable overlap between those disorders and eczema; in fact, they’re all part of the so-called “atopic march,” and having one predisposes a person to the others. Given this overlap, it’s reasonable to wonder: do air purifiers help with eczema?
“Heavy heaven” and the air we breathe
Air pollution has been a problem since the dawn of civilization. As human settlements grew denser, fumes from fires, agriculture, and metallurgy began to contribute to worsening air quality.
In ancient Rome, the thick, grey smoke that perpetually smudged the city’s sky was called gravioris caeli–”heavy heaven.” Noted philosopher Seneca mentioned in AD 61 that the city’s “poisonous fumes” sickened him, and in 535, Emperor Justinian declared that the right to clean air was “common to mankind.”
The advent of the Industrial Revolution saw entire cities covered in black palls of coal smoke. The famous “London fogs” from the 1800s inspired the scientific study of air pollution and established it as a public health concern.
In the post-World War I United States, the rise of the automobile intersected with industrial growth to create noxious blankets of smog in the major cities. At one point during World War II, unusually thick smog in Los Angeles raised a panic among Angelenos who thought that Imperial Japan had targeted their city for chemical warfare.
By the 1960s, Congress was forced to contend with the growing problem, enacting the first Clean Air Act in 1963 and imposing auto emissions standards two years later.
Air pollution is a nasty brew of toxic gases (such as ozone, carbon monoxide, and sulphur dioxide), volatile organic compounds (VOCs) such as formaldehyde, and particulate matter such as smoke, dust, and fine, microscopic particles. The World Health Organization (WHO) estimates that air pollution contributes to about 7 million premature deaths a year.
Air pollution isn’t just an outdoor concern. Around 4 million of yearly pollution-related deaths are caused by indoor pollution in homes, says the WHO.
A number of different sources contribute to indoor air pollution. Among these are fuel burned for heating and cooking, VOCs in paints, building materials and furnishings, and tobacco smoke.
Indoor pollution can also result from the introduction of outdoor pollutants–as anyone currently struggling with the smoke from the Canadian wildfires can attest.
According to the WHO, “pollutants in household air pollution inflame the airways and lungs, impair immune response and reduce the oxygen-carrying capacity of the blood.” This contributes to stroke, heart disease, lung disease, and certain cancers.
Indoor air quality refers to the overall health of the air we breathe indoors. Levels of carbon dioxide, carbon monoxide, ozone, volatile organic compounds (VOCs), mold, and particulate matter all factor in when measuring air quality, as do levels of bacteria and viruses.
Pollution, indoor air quality, and eczema: what you Should know
Multiple studies have established a strong connection between pollution and eczema. A 2015 study in China found that increases in air pollution levels corresponded with increased reports of doctor’s visits for eczema. A similar Korean study reached the same conclusions in 2022.
Air pollution influences the development of eczema primarily by damaging the skin barrier and triggering increased inflammation. Many cause oxidative stress in the skin cells, which damages proteins such as filaggrin that are critical to barrier function.
This pollution seeps through cracks around windows and HVAC units to diminish indoor air quality. Add some common household allergens, like pet dander, and you have a perfect storm for eczema sufferers.
Do Air Purifiers Help With Eczema
Most air purifiers work by using high-powered fans to draw air through a series of fine mesh filters. These filters “catch” small particles and keep them from being released into the air again.
Some studies show that a properly-used air purifier can remove up to 50% of airborne pathogens and 60% of particulate matter from indoor air.
Choosing the right air purifier
Not all air purifiers are created equal! Here are some things you should look for when you shop for an air purifier:
Choose one with a HEPA filter. HEPA stands for “high efficiency particulate air.” By Environmental Protection Agency (EPA) standards, a HEPA filter can remove 99.97% of airborne particles with a size of 0.3 microns (smaller than the width of a human hair)!
- Choose the right CADR. The Association of Home Appliance Manufacturers (AHAM) assigns a Clear Air Delivery Rate (CADR) to air purifiers it tests. The AHAM website explains it this way: “CADR indicates the volume of filtered air an air cleaner delivers, with separate scores for tobacco smoke, pollen and dust. The higher the CADR number for each pollutant, the faster the unit filters the air.”
In theory, a purifier with a CADR of 400 for tobacco smoke should add an equivalent of 400 square feet of fresh air every minute to dilute the smoke particles in a room. Choose the highest CADR score possible for your individual concern.
Air purifiers with an AHAM rating have had manufacturers’ claims about room size and CADR verified. If a company claims that its AHAM VerifideⓇ air purifier can handle a 400 square foot room with a CADR of 388 for tobacco smoke, you can trust it to do just that.
Some manufacturers choose not to pursue AHAM verification. This doesn't mean that they’re untrustworthy–just that you should research the product and see how its claims stack up against testing.
Some air purifiers claim to use ozone to purify the air. Ozone is a toxic gas. It’s hazardous to you, your pets…even your houseplants. Avoid these.
Ultraviolet (UV) germicidal purifiers claim to kill bacteria and viruses with ultraviolet lamps. If you’re considering one of these air purifiers, look for consumer testing reviews and scientific studies.
At the end of the day, a good, AHAM-certified air purifier with a HEPA filter is the best option for most of us.
To get the most from your air purifiers keep the air purifier as close to the center of the room as possible.
This doesn’t mean you have to obstruct the flow of traffic for a perfect, central placement; just don’t shove it into a far corner. It should have “room to breathe” for best results, so give it a few feet of clearance from walls, curtains, and furnishings. Here are some other tips:
Do Air Purifiers Help With Eczema - Answered:
Appropriate air purifiers can reduce indoor particulate matter and, in some cases, VOCs and toxic gases. If you or your child has eczema, consider getting an AHAM-certified air purifier with a HEPA filter.
Indoors or outdoors, poor air quality can contribute to eczema flares or worsen eczema symptoms. Pollutants harm the skin barrier by causing oxidative stress and moisture loss; some trigger inflammation. Indoor air pollution is of concern because we spend most of our time indoors. Remember, nothing will beat a good quality eczema cream with dealing with a flare, but paying attention to the air quality when you can, can help too.