I have a health goal for the new year that doesn’t require me to get out of bed earlier or eat fewer cookies. I am an atmospheric chemist and will be committing to clean air at home.
People in the U.S. spend as much as 90% of their lives indoors. Overall, air pollution is responsible for approximately 135,000 premature deaths per year in the U.S. And levels of some chemicals can be two to five times higher in indoor air than outdoors.
Fortunately, there are some straightforward ways to improve your home’s air quality this year, in three major categories of activity.
Cooking
Cooking is a major source of indoor air pollution.
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Not all chemicals that cooking produces are bad, but some react to form other chemicals that like to clump together to form particulate matter. When inhaled, these particles enter the lungs and can then pass into the bloodstream, increasing people’s risk of heart disease and decreasing lung function.
The amount of particulate matter produced from your cooking depends on the food type, oil used and cooking temperature. High-fat-content foods, such as cheese, pork and bacon, emit the most particles, especially when cooked at high temperatures. Sunflower oil produces the least amount of particulate matter, followed by vegetable oil and then olive oil.
Cooking with a gas stove produces more particulate matter than with an electric stove, and the gas stove also emits other hazardous chemicals such as nitrogen dioxide and benzene.
Two simple and effective measures to keep kitchen air clean and prevent particulate matter from spreading through the home are using your range hood fan and opening nearby windows while cooking. The suction will move harmful chemicals out of your home and away from your lungs, and the fresh air will dilute what remains.
Personal care
In large cities such as Los Angeles and New York City, there are enough volatile organic chemicals from consumer products – paints, adhesives and personal care products – in the outdoor air to rival those produced by traffic and industry. Many of those products are first used indoors before they escape outside.

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Government regulations limit the amount of chemicals allowed in some kinds of consumer products, such as adhesives and construction materials, because of their contribution to smog, but personal care products that contain fragrances remain largely unregulated.
Many common options for shampoo, conditioner, mousse, body wash, deodorant, lotion, laundry detergent and dryer sheets contain fragrance mixes composed of several chemicals, with the sole purpose of providing a pleasant aroma to consumer products. Fragrances release volatile organic compounds such as limonene, linalool, galaxolide, eugenol and diethyl phthalate that can react to form particulate matter. In addition to health risks from particulate matter formation, strong fragrances can trigger headaches, difficulty breathing, skin irritation and other physical responses that warrant concern.
I’m not suggesting you be smelly or live an unscented life. But consider whether you could choose perhaps three products that have your very favorite scents, and for the others buy fragrance-free versions when you need to resupply. That would reduce the volatile organic compounds and the ensuing potential for particulate matter formation without really changing how you smell.
Cleaning
Cleaning your home can improve indoor air quality by temporarily reducing the amount of chemicals on surfaces that can find their way back into the air. For example, oleic acid from cooking, squalene from human skin and bisphenol A from hard plastics can remain on surfaces for years if undisturbed.

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But there’s a caveat: Cleaners are made of strong chemicals, designed to disinfect, degrease and eliminate odors, that may do more harm for air quality than good. To that end, the healthiest option may be found by carefully choosing the right cleaner for the job. For less intensive tasks like dusting or cleaning crumbs off the counter, consider avoiding strong disinfectants like bleach, hydrogen peroxide and a category of chemicals called quaternary ammonium compounds that can often be found in disinfectants, hair products and fabric softeners.
However, if you are cleaning the bathroom or a forgotten, moldy leftovers container, you may prefer a stronger disinfecting product. Be aware that studies have found bleach cleaners can produce harmful chlorinated byproducts, such as chloroform and carbon tetrachloride, which are possible carcinogens and worth avoiding altogether.
Still, nearly all commercially available cleaning products contain volatile organic compounds – like limonene for citrus scent, lactic acid for limescale and bacteria removal, and 2-phenoxyethanol for product preservation – that will increase chemical and particulate matter concentrations in the immediate area.
In this case, dilution is key to limiting your exposure. Increase ventilation while using these products by running the bathroom fan, opening windows while you clean, and using only as much of a cleaning product as is really required to do the job.
Overall improvements
Opening windows is an effective and often overlooked solution to improve indoor air quality. Chemicals that may be harmful to you in a closed space, where they are more concentrated, become less harmful when they are diluted and spread throughout the massive outdoor atmosphere. But avoid opening windows when smog, ozone or wildfire smoke levels are high outside, which would create an opportunity for outdoor air pollution to come indoors.
Luckily, your city or your neighbors are likely collecting outdoor air quality data that is publicly available to you, so you can track whether to open your windows.

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If air pollution is too high outside, an indoor air cleaner may be a better option. And you don’t have to shell out big bucks, either. Air quality engineers have shown that a homemade air cleaner using a box fan, four air filters and duct tape – all commonly available at hardware stores or online – can cost under $70 and be as effective at cleaning the air as factory-made appliances.
Overall, the best way to improve air quality is to put fewer harmful chemicals into the air in the first place. While scientists and policymakers can measure and regulate outdoor air quality, it’s up to us all to keep the air in our own homes clean and healthy.