12 Things That Pollute the Air Inside Your Home

Updated: Jan. 27, 2021

Levels of air pollution indoors can exceed what's outside. Follow these steps for pollution prevention and your lungs will thank you.

The polluted air in your home

People tend to focus on the dangerous particles in the outdoor air—and for good reason: Air pollution can have seriously detrimental effects on your body. But the air in your house can be up to five times more polluted than what you’re breathing outdoors, according to the Environmental Protection Agency. And don’t forget you spend up to 90 percent of your time indoors, reports the American Lung Association. That’s a lot of exposure to potentially contaminated air.

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What’s in your air

Now that energy-efficient buildings keep air leakage to a minimum, there’s a big uptick in the concentration of air pollutants, says Ian Colbeck, PhD, professor in the school of biological sciences at the University of Essex in the UK. Pollutants that should pique your concern include tobacco smoke, nitrogen dioxide, carbon monoxide, particulate matter agents, formaldehyde, volatile organic compounds (VOCs), and radon, he says. Here are 15 ways to decrease indoor air pollution in your home.

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The risks of indoor air pollutants

The sneaky sources of pollution you find indoors can trigger asthma attacks, heart disease, strokes, and some cause lung cancer, says Janice Nolen, assistant vice president of national policy at the American Lung Association. “There are significant risks for anyone, particularly children and the elderly,” she says.

Paint cans and brushes top view


After slapping on a couple coats, you might store nearly empty paint cans in your garage. “The cans can give off VOC gases in the garage, causing problems with indoor and outdoor air quality that impacts breathing,” says Nolen. Some of these VOCs cause cancer. Look for low-VOC paints. Here are 7 things that cause lung cancer that aren’t smoking.

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Aerosol sprays

Sometimes the products inside your home are not only damaging indoor air, but contributing to outdoor pollution as well. A surprising study in 2018 in Science concluded that household items like aerosols, including cleaning and personal care products, make up half of outdoor VOC emissions in cities. Decrease this pollution load by avoiding using aerosol sprays whenever possible.

Cleaning products

You may love when your home “smells” clean, but many cleaning supplies are also a big source of VOCs in your air. For instance, the presence of bleach in household cleaners combined with a common citrus ingredient called limonene can increase harmful airborne particles as you clean, according to research from the journal Environmental Science & Technology. To reduce the amount cleaners release, Nolen recommends using unscented products and cleaning with basic, natural things like water and vinegar or baking soda. “These are really good cleaning tools and can be helpful in reducing your exposure indoors,” she says. These are the toxic kitchen products you should definitely watch out for.

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Electronic cigarettes

They might not give off any smoke, but using an e-cigarette releases vapor into the surrounding environment when you exhale. E-cigarette vapor can contain ultra-fine particles at greater concentrations than conventional cigarettes and carcinogenic chemicals, per the American Nonsmokers’ Rights Foundation. As such, they’re banned in smokeless areas in 19 states–and that’s a good thing when it comes to your lungs. It’s not just your lungs. Here are the other ways e-cigarettes harm your body.

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Their divine smell and ambiance are nice, but candles release a lot of trouble. “Candles can be substantial sources of ultra-fine and fine particles that contribute substantially to the exposure to indoor particulate matter, which is associated with inflammation in lungs,” says Colbeck. What’s more, scented candles can also emit harmful formaldehyde. If you really like to use candles, look for beeswax or soy options, he says. Another warning: if you have asthma, candles can be especially troublesome for triggering an attack.

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3D Printers

Now that 3D printers are rising in popularity and are available for home use, you should evaluate their safety before bringing one in. In a 2019 study in Environmental Science & Technology,  researchers found that 3D printers emit particles that can be inhaled and harm your lungs. What’s more, when certain plastic filaments inside the machine get super hot, they spew out more of these dangerous compounds. When in use, keep your distance from printers and use them in a ventilated area.

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Air fresheners

Some people looking for a pleasant-smelling abode turn to air fresheners. “These can emit over 100 different chemicals; some of these can react to form a new set of pollutants,” explains Colbeck. The cocktail can trigger migraines, asthma attacks, and breathing troubles. To keep air smelling clean, the Environmental Working Group suggests a simple solution: Open a window or run a fan. You might also consider using an air purifier or getting an air-cleaning plant.

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Your humidifier

To score smooth skin in the winter, you may crank up your humidifier. But keep it below 50 percent humidity, recommends Nolen. Any higher encourages mold formation and dust mites to flourish, two huge sources of indoor allergens that can impact your ability to breathe.

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Granite countertops

Granite countertops can produce radon, a naturally occurring radioactive gas. Radon is the second leading cause of lung cancer in the United State. But you can breathe easy here: The EPA notes that indoor granite doesn’t significantly increase indoor radon. The main source is through cracks in your home, like in walls and the foundation. Rather than replacing your countertop, focus your efforts on plugging up these areas in your home. First, check if your home has radon by ordering a radon test kit. You can also hire a professional to test your house.


Wood-burning fireplaces

Lighting a fire in your home may make things cozy, but it can also muck up your air. Burning wood and cleaning up the ash later can create high levels of particulate pollution and carbon monoxide exposure in your home, says Colbeck. (He notes that the amount depends on factors like the size of the room and how well ventilated it is.) Here are other ways your fireplace can be toxic.

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Your stove

Attention, home chefs: Gas stoves may whip up Pinterest-worthy meals, but the flame creates nitrogen oxide emissions, and cooking itself produces particles, says Nolen. “You’re not going to give up cooking, but be sure to use an exhaust fan to get rid of these things,” she says. While the vent above the stove is a good first start, that’s usually not enough unless you know it’s ventilating the air outside your home. (Some simply move the air to another part of the kitchen, she says). A second option: Crack a window while you cook.

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Your air purifier

If you can believe it, some air filtration systems will make your air worse. “Avoid anything that generates ozone, which some are marketed to do,” says Nolen. “Indoors, ozone can be harmful to your health,” she adds. If you are buying a filtration device, look for a model that has a HEPA filter, she says, although preventing pollutants entirely—skipping this type of purifier—is your best bet for cleaner air indoors.

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You can’t get everything out of your home

A normal existence leads to an increase in some indoor air pollutants—walking, cleaning, or cooking can all add to the load, says Colbeck. You can’t avoid doing those things, and you shouldn’t. Just take a few measures to keep the air inside safer, he recommends: Use a vacuum with a HEPA filter, open windows when you’re using pollutant-releasing products, and take your shoes off at the door. Your lungs will thank you. Watch out for more ways your house may secretly be making you sick.