Warning as Gas Stoves May Kill 19,000 Americans Each Year

Having a gas stove in your home is bad for your health, researchers have found, and it could kill thousands of people across the country every year.

People living in homes with a gas or propane stove breathe unhealthy amounts of nitrogen dioxide or NO₂, one of the pollutants from car exhaust, according to a paper in the online journal Science Advances. Long-term exposure to this NO₂ could trigger asthma in hundreds of thousands of people, as well as killing as many as 19,000 people annually.

This finding comes as the U.S. Department of Energy announced new energy-efficiency guidelines for gas and electric stoves earlier this year, which has brought a backlash.

Gas stoves work by burning gases, usually natural gas—a mixture of hydrocarbons but mostly methane—or propane. This burning can release byproducts, including harmful gases like carbon monoxide and nitrogen oxides like NO₂.

NO₂ primarily affects the respiratory system. It can cause or worsen respiratory diseases, particularly asthma, leading to symptoms like wheezing, coughing, colds, flu and bronchitis. Prolonged exposure can decrease lung function and increase the risk of respiratory infections.

There is also some evidence that NO₂ can exacerbate existing heart conditions, leading to increased hospital admissions and even premature death. Long-term exposure to NO₂ may also affect the development of the lungs in children.

Around 38 percent of U.S. households have gas stoves, according to the federal Energy Information Administration, although certain states have much higher numbers of gas stoves than others.

Pollutant gases from gas and propane stoves may be responsible for as many as 200,000 current childhood asthma cases, 25 percent of which are due to NO₂ alone, the paper said.

"We found that just how much gas you burn in your stove is by far the biggest factor affecting how much you're exposed. And then, after that, do you have an effective range hood—and do you use it?" said study co-author Yannai Kashtan, a Ph.D. student in Earth system science at Stanford University, in a statement.

The researchers also found that long-term exposure to the NO₂ in American households with gas stoves may lead to 40 percent as many deaths as those caused by secondhand smoke, which comes to around 19,000 people each year. This estimate doesn't even factor in the short bursts of NO₂ that are often seen in homes with gas stoves.

"I didn't expect to see pollutant concentrations breach health benchmarks in bedrooms within an hour of gas stove use and stay there for hours after the stove is turned off," study author Rob Jackson, a professor in Earth system science at Stanford, said in the statement. "It's the whole family's problem."

Using a gas or propane stove in the home increases exposure to NO₂ by an estimated 4 parts per billion on average during a year, which is about three-quarters of the way toward the NO₂ exposure level classified as unsafe in outdoor air by the World Health Organization.

"That's excluding all outdoor sources combined, so it makes it much more likely you're going to exceed the limit," said Kashtan.

The paper also reveals that smaller homes are more at risk of these effects, with people in small two-bed apartments being exposed to around twice as much NO₂ as the national average and four times that of people living in homes over 3,000 square feet.

"Electric stoves emit no nitrogen dioxide or benzene. If you own a gas or propane stove, you need to reduce pollutant exposures using ventilation," Jackson said.

The effect of home sizes means that there is a major trend in NO₂ exposure among those with low incomes as well as racial and ethnic groups. The paper found that American Indian and Alaska Native households had a 60 percent higher exposure to NO₂ than average, while Black and Hispanic or Latino households had a 20 percent higher exposure than average. This also is compounded by the fact that these communities may be exposed to higher levels of NO₂ from other sources, including vehicle exhaust.

"People in poorer communities can't always afford to change their appliances, or perhaps they rent and can't replace appliances because they don't own them," Jackson said. "People in smaller homes are also breathing more pollution for the same stove use."

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