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Tag: indoor air quality

  • Do Houseplants Really Clean Indoor Air?

    Do Houseplants Really Clean Indoor Air?

    Evidence: Strong

    Key takeaways

    • The idea that houseplants clean indoor air mostly comes from sealed-chamber experiments, not real homes.
    • A 2019 review estimated you’d need roughly 10 to 1,000 plants per square meter to match the air exchange a building already gets from ventilation.
    • Ventilation, cutting pollution at the source, and HEPA air purifiers do far more for indoor air.
    • Houseplants are still great for mood and decor, just not as air purifiers.

    You’ve probably seen lists of the “best air-purifying plants.” But do houseplants really clean indoor air? The research says: not in any meaningful way in a normal home. Here’s why, and what actually works.

    Where the myth started

    Much of the claim traces back to a NASA study from 1989 that tested plants in small, sealed chambers. In those chambers, plants did reduce some chemicals over many hours. But a sealed box is very different from a home, where air is constantly exchanged with the outdoors.

    What newer research shows

    In 2019, researchers Bryan Cummings and Michael Waring reviewed decades of plant studies in the Journal of Exposure Science & Environmental Epidemiology. They converted the results to real-world terms and estimated that it would take between 10 and 1,000 plants per square meter of floor space to match the air cleaning a typical building already gets from ventilation. In other words, a few plants on a shelf make essentially no measurable difference.

    Why we rated this “Strong”: A peer-reviewed review analyzed many studies and found consistent results, and it matches the EPA’s guidance that ventilation and source control are the most effective ways to improve indoor air. How we rate evidence

    What actually improves indoor air

    1. Reduce sources: choose fragrance-free products and skip air fresheners. See cleaner home-cleaning swaps.
    2. Ventilate: open windows when outdoor air is good and run kitchen and bathroom exhaust fans.
    3. Filter: use a portable air cleaner with a HEPA filter sized for the room, as recommended in the EPA’s guide to air cleaners.
    4. Upgrade HVAC filters to a higher-efficiency filter your system can handle.
    5. Avoid ozone generators, which can produce a lung irritant.

    Cleaner swaps to try

    We may earn a commission if you buy through links in our product picks. It never affects our ratings.

    • Portable HEPA air purifier sized for your room
    • Higher-efficiency HVAC filter
    • Fragrance-free cleaners
    • Houseplants, for beauty and mood rather than air cleaning

    The bottom line

    Keep your plants: they can brighten a room and lift your mood. But for cleaner indoor air, focus on fewer pollution sources, better ventilation and a HEPA air purifier. More ideas in Swaps and our Avoid List.

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    Sources

    1. Cummings BE, Waring MS. Potted plants do not improve indoor air quality: a review and analysis of reported VOC removal efficiencies. J Expo Sci Environ Epidemiol. 2020;30:253-261.
    2. U.S. Environmental Protection Agency. Guide to Air Cleaners in the Home.
  • Cleaner Home-Cleaning Swaps That Actually Work

    Cleaner Home-Cleaning Swaps That Actually Work

    Evidence: Moderate

    Key takeaways

    • Many cleaning products release fumes that can irritate the lungs, especially in small or poorly ventilated spaces.
    • Simple ingredients like soap, baking soda and vinegar handle most everyday cleaning.
    • Never mix bleach with vinegar or ammonia. It creates toxic gases.
    • When you buy cleaners, the EPA’s Safer Choice label is a useful shortcut.

    You don’t need a cabinet full of harsh sprays to keep a clean home. Many everyday jobs can be handled with a few simple ingredients, and switching to non-toxic cleaning options can cut down on fumes and fragrance in the air you breathe. Here’s what works, what doesn’t, and the one safety rule everyone should know.

    Why switch to cleaner cleaning products?

    According to the American Lung Association, many cleaning products can release chemicals that irritate the eyes, nose and throat, and some can worsen asthma. Fragranced products and aerosol sprays add to indoor air pollution. Using simpler products and ventilating while you clean reduces your exposure.

    The cleaner cleaning toolkit

    • Liquid castile soap or mild dish soap: lifts grease and dirt from most surfaces
    • Baking soda: a gentle scrub for sinks, tubs and stovetops, and a deodorizer
    • White vinegar: cuts mineral buildup and soap scum; good for glass
    • Microfiber cloths: trap dust and grime with just water
    • A spray bottle and a scrub brush

    Simple swaps that actually work

    All-purpose cleaner

    Mix warm water with a small squirt of dish soap or castile soap in a spray bottle. It handles counters, tables and most sealed surfaces.

    Glass and mirrors

    Equal parts white vinegar and water, wiped with a microfiber cloth, leaves fewer streaks than many commercial sprays.

    Sinks, tubs and stovetops

    Sprinkle baking soda, scrub with a damp brush or sponge, then rinse. For stubborn spots, make a paste with a little water and let it sit.

    Shower soap scum and hard-water spots

    Spray undiluted vinegar, let it sit for 10 to 15 minutes, then scrub and rinse.

    Air freshening

    Open windows, run the exhaust fan, and use baking soda in the fridge and trash. Skip plug-ins and aerosol fresheners. See what “fragrance” on a label can hide.

    What simple cleaners can’t do

    Vinegar and baking soda are great cleaners, but they aren’t registered disinfectants. When you need to kill germs, such as after handling raw meat or when someone in the house is sick, use a product registered as a disinfectant and follow the label’s directions, including how long the surface must stay wet. Vinegar also shouldn’t be used on natural stone like granite or marble, because its acid can damage the finish.

    The safety rule: never mix these

    • Bleach + vinegar (or other acids): releases chlorine gas
    • Bleach + ammonia: releases toxic chloramine gases
    • Different drain cleaners with each other

    Store cleaners in their original containers, keep them away from children and pets, and ventilate whenever you clean.

    Why we rated this “Moderate”: Respiratory irritation from cleaning chemicals and the dangers of mixing bleach are well documented. The benefits of switching to simpler products for the average healthy household are reasonable but less directly measured, so we rate this Moderate. How we rate evidence

    Buying cleaners? Look for Safer Choice

    If you’d rather buy ready-made products, the EPA’s Safer Choice program certifies products whose ingredients meet the agency’s safety criteria. Look for the Safer Choice label, and choose fragrance-free versions when available.

    Cleaner swaps to try

    We may earn a commission if you buy through links in our product picks. It never affects our ratings.

    • Microfiber cloth set: cleans most surfaces with just water
    • Unscented castile soap: the base for most DIY cleaners
    • Safer Choice-certified, fragrance-free cleaners for when you want ready-made
    • Glass spray bottles for homemade mixes

    The bottom line

    Soap, baking soda, vinegar and a microfiber cloth handle most household cleaning, with fewer fumes and less fragrance. Use a registered disinfectant when you truly need to kill germs, never mix bleach with acids or ammonia, and look for the Safer Choice label when you buy. More cleaner ideas in Swaps.

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    Sources

    1. American Lung Association. Cleaning Supplies and Household Chemicals.
    2. U.S. Environmental Protection Agency. Safer Choice.