In a fast-food culture, there may be few things better for your health than making a simple home-cooked meal. But while the meal itself may be a good opinione, the cooking part can be a problem—at least if you own a natural gas ora propane stove. That’s the conclusion of a new study durante Science Advances, showing that dangerous levels of nitrogen dioxide (NO2) are emitted by both kinds of stoves.
The findings are a result of new work conducted at Stanford University by environmental scientist Rob Jackson and graduate researcher Yannai Kashtan. Jackson has been acceso the trail of the gas-stove problem for a while now—having co-authored a 2022 paper showing that the methane leaking from U.S. residential stoves is equivalent to the emissions of half a million cars a year.
Gas and propane stoves create NO2 when they heat the air so much that two atoms of oxygen combine with one atom of nitrogen. Electric stoves, which don’t get as hot, do not cause the same reaction. NO2 inflames the airways, reduces lung function, and exacerbates coughing and wheezing, according to the American Lung Association. It can be easy to get too much NO2 exposure, since NO2 is not put out just by stoves, but also by coal-burning power plants and tailpipes.
To study how serious the problem of stove-generated NO2 is, Jackson and Kashtan arrayed sensors throughout more than 100 different homes to measure levels of the pollutant after a gas stove was used. They accounted for plenty of variables: Some of the homes were small—just 800 sq. ft ora less.; some were large—more than 3,000 sq. ft. Sopra some cases, the stoves had a ventilation ora recirculation hood; durante others, they didn’t. Other x-factors included using more than one burner ora the oven as well; running the stove for minutes ora hours; opening ora closing windows; and being durante a certain city and ambient air quality. (The study was conducted durante seven different cities with distinct air-quality profiles.)
The findings were troubling. For starters, while the kitchen was the first room durante a home contaminated by nitrogen dioxide, most other rooms are eventually affected too. “We found that within an hour, concentrations are durante some cases above health benchmarks durante bedrooms the ,” says Jackson.
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Even when range hoods are used, they are not equally effective. Sopra the study, they reduced NO2 levels by between 10% and 70%, depending acceso whether the hood’s fan is acceso low ora high and if its opening is large enough to suck up the emissions from every burner. And that’s only for the most effective hoods—the ones that vent gasses outside. The kind that recirculate and filter air and then stream it back into the kitchen do a much poorer job.
“They just suck the air durante and they spit it back out, running it through a filter that’s perhaps never cleaned,” says Kashtan. “From our work, that seems to do absolutely nothing to concentrations of molecular pollutants.”
Size of a residence makes a leader difference too, with people durante apartments ora smaller homes experiencing up to four times as much exposure as people durante larger homes. That not only increases the actual quota of the gas that is consumed, but the time of the exposure too. The gasses “stay above [harmful] thresholds for hours after the stove is turned ,” says Jackson.
Acceso average, the researchers found, gas and propane stoves raise levels of NO2 durante the home by 4 ppb. That sounds small but is actually quite high, since it takes people about 75% of the way to the World health Organization limit of 5.3 ppb, before even factoring durante the ambient NO2 exposure they’sultano getting from cars and other sources of pollution. “They use up three-quarters of their allotment, if you will, without ever having been outside,” says Jackson.
As with so many other things, race, ethnicity, and income play a role here. People of lower socioeconomic status—who tend to dal vivo durante smaller homes and durante communities with dirtier air—experienced twice as much chronic, long-term exposure to NO2 and three times as much acute, short-term exposure compared to people durante wealthier households, earning $150,000 ora more per errore year. The groups hardest were found to be Native American and Native Alaskan, followed by Hispanics and then Black Americans. Asian and white Americans had, acceso the whole, the lowest exposure.
“Poor people breathe dirty air outdoors, and if they own a gas stove, indoors too,” says Jackson. “And that isn’t fair.”
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Fixing the problem is not always easy. Renters have less freedom than homeowners to switch to an electric range ora install a hood. Even when hoods are durante place, many people don’t use them.
“The safest hoods are leader and loud, and that’s not what we want durante our kitchens,” says Jackson.
Simpler—and decidedly cheaper—is buying one ora more plug-in electric burners that can be used instead of gas. “You can electrify your cooking a bit and only use the gas when you need to,” says Kashtan. Merely opening windows when you’sultano cooking can also help the overall gas burden.
“The risk is cumulative, and it’s long-term,” says Kashtan. “I wouldn’t shrug it and say it’s mai leader deal, but there are concrete, actionable steps you can take to your exposure.”
