The internet has been ablaze in recent days over gas stoves, especially over the fact that they are harmful to human health and may or should be banned in the United States. But this is not a new problem.
Scientists have long known that gas stoves emit pollutants that irritate human airways and can cause or exacerbate respiratory problems. The recent furor appears to have been sparked by comments recently made by Richard Trumka, Jr., a commissioner of the Consumer Product Safety Commission (CPSC), a government agency that addresses the risk of illness and injury from various products. Speaking about the commission’s plans to potentially regulate gas stoves, Trumka told Bloomberg News that “any option is on the table. Products that cannot be made safe can be banned.”
In response, conservative politicians (And Democratic Senator Joe Manchin) strongly opposed what they perceived as an attempt to ban gas stoves. House Republicans even introduced legislation to ban the CPSC from outlawing popular cooking appliances. The CPSC chairman recently clarified that the commission is not planning any kind of ban but is seeking public comment to make gas stoves safer.
American scientist spoke to several experts about the health and environmental risks posed by gas stoves. The answers below are based on their responses.
Do gas stoves produce emissions harmful to human health?
Gas stoves burn natural gas, which generates a variety of invisible by-products. The greatest concern for human health is nitrogen dioxide (NO2). This gas is produced when natural gas is burned at high temperatures in the presence of nitrogen in the atmosphere, according to Josiah Kephart, assistant professor in Drexel University’s department of environmental and occupational health. “We’ve known that for a long time [nitrogen dioxide] it has many detrimental health effects,” he says.
The Environmental Protection Agency regulates outdoors NO2 emissions, setting standards for their safe exposure limit. But there are no similar standards for indoor exposure. However, studies dating back decades have shown harmful effects of NO2 in gas stoves.
“Our knowledge of the health impacts of NO outdoors2 has grown dramatically over the past 10 years, and we’ve found that it poses a much greater health risk than perhaps we previously thought,” says Kephart. And the impacts of breathing NO2 indoors are no different than outdoors. “It has the same effect on your body,” she says.
Studies have also found that unburned natural gas escapes from stoves and this gas contains benzene, a known carcinogen. Also, cooking in general creates fine particulate matter with a diameter of 2.5 microns or smaller (PM2.5), a known irritant that can cause or exacerbate respiratory problems.
What are the known health effects of NO2 exposure?
In a 1992 meta-analysis of studies on this topic, scientists at the EPA and Duke University found that exposure to nitrogen dioxide, comparable to that from a gas stove, increases the chances that children will develop a respiratory disease of about 20%. Since then, numerous other studies have documented the effects of gas stove exposure on respiratory health. A 2013 meta-analysis of 41 studies found that gas cooking increases the risk of asthma in children and that NO2 the exposure is related to currently having wheezing. Most recently, a study released last December found that 12.7 percent of childhood asthma cases in the United States can be attributed to gas stove use. (This result was essentially obtained by multiplying a previously reported measure of the risk of developing asthma from exposure to gas stoves by the proportion of children living in households with gas stoves.)
The American Gas Association (AGA), a natural gas industry group, released a statement rejecting the December 2022 study that linked gas cooking with asthma. The statement said the study authors had not conducted measurements of real-life appliance use and were ignorant of some of the scientific literature on this topic. The AGA cited a separate study that found no evidence of a link between gas cooking and asthma diagnostic symptoms.
American scientist it also reached out to the American Public Gas Association, a nonprofit trade association, for comment but had not received responses to questions as of press time.
Most studies on the health effects of cooking gas are based on observation because it would obviously be unethical to intentionally expose children to environmental hazards, she says Ulrike Gehringassociate professor at the Institute for Risk Assessment Sciences at Utrecht University in the Netherlands and co-author of the 2013 meta-analysis. However, some previous studies have measured NO2 concentrations in various indoor environments and have shown that people with asthma experience more severe symptoms when exposed to higher levels of the gas. Although observational studies cannot prove that cooking with gas causes asthma, Gehring says, taking into account other risk factors such as parental asthma and secondhand tobacco smoke “boost our confidence” that it does.
In addition to acute effects such as asthma symptoms, long-term exposure to nitrogen dioxide has also been linked to chronic lung disease and increased mortality in general.
Are the effects visible in both children and adults?
While most of the relevant research has focused on children, there have been a few studies on adults. Some of these investigations have found a stronger association between gas stove use and respiratory symptoms in women, suggesting they may be exposed to more nitrogen dioxide, perhaps while cooking, Gehring says.
If I already have a gas stove, what precautions can I take to reduce the risks?
If you have the means, you can replace your gas stove with an electric one. The Inflation Reduction Act provides discounts of up to $840 on the purchase of new appliances, including stoves and cooktops. (Eligibility varies by state and income level.)
But if you can’t afford to buy a new stove or if you rent an apartment and can’t change appliances, experts note that there are still things you can do to reduce your risk of exposure.
If your stove has a top vent, you should use it every time you cook, and ideally it should vent to the outside. “You should always turn on the exhaust fan whenever you use the stove, it doesn’t matter if you’re just boiling water,” says Eric Lebel, senior scientist at PSE Healthy Energy, a nonprofit policy and research institute in Oakland. California “Even if what you’re cooking doesn’t smell, if that flame is on, you should have the exhaust on to help reduce exhaust gas concentrations, or those [nitrogen oxide] by-products, in the kitchen.”
Unfortunately, many people don’t use vents. They work best when they’re running at full volume, which can be quite loud, and the filter should be changed about every three months, Kephart says. And some overhead vents simply recirculate the air in a room. If you don’t have a “range hood” that vents to the outside, you can open a window and run a fan to increase ventilation, says Lebel. Portable air purifiers can help too, says Kephart, although they don’t completely remove NO2.
You can reduce the operating time of the stove by using electric kettles and pressure cookers. You can also buy an electric hob; some are available for around $100 or less.
Do gas stoves produce emissions that are harmful to the climate?
Yes. Burning natural gas produces carbon dioxide, the most common greenhouse gas. And unburned natural gas contains another potent culprit: methane. A 2022 study by Lebel and his colleagues found that gas stoves leak this unburned methane, which isn’t directly harmful to human health but builds up in the atmosphere, where it traps heat and contributes to climate change. Lebel and his team found that methane emissions from gas stoves in US homes could have the same impact on the climate as half a million cars.
And the problem isn’t just our stoves themselves. “We have known for years that there are methane leaks in the [natural gas] distribution system, especially in East Coast cities, where the infrastructure is much older,” Lebel says. “And then, even further upstream than that, there are transmission and manufacturing losses.” All of these losses add up. and contribute to the climate impact of the natural gas supply chain, he adds.
What about the other gas appliances?
Gas water heaters, furnaces and dryers also produce emissions and may be leaking methane as well, Lebel says. People may not be exposed to these emissions as directly as they are when cooking on a stove, but these appliances still produce pollution. The only way to completely prevent it is to use electrical appliances, says Lebel.
Should gas stoves be regulated? And if so, how?
Existing gas stoves are unlikely to be banned altogether, so if you have a gas stove and want to keep it, you can. But regulatory bodies could, for example, try to set requirements for all gas stoves to be sold with a range hood that vents to the outside, or for pipes to be better fitted to prevent leaks. And some cities, including New York and several California cities, have already passed legislation requiring gas stoves and other gas appliances to be phased out in some types of new construction.
But I like my gas stove. Doesn’t it cook better?
This is a common response among people who like to cook on gas. But in some cases, this view can be influenced by paid promotions from the gas industry. Gas stoves heat up faster than conventional electric ones. But induction stoves, a type of electrical appliance that heats food by inducing an electromagnetic field, are also very fast and more energy efficient.
If you love your gas stove, you don’t necessarily have to get rid of the appliance. But it’s a good idea to take some precautions to reduce the risks to you and your family.