Pollution from gas stoves is responsible for over half of some Americans’ nitrogen dioxide (NO2) exposure, a toxin associated with asthma, according to a study in PNAS Nexus. This study offers the first nationwide estimates of residential NO2 exposure at the community level.
The research evaluated outdoor and indoor emissions, finding that stoves were the main source of indoor NO2 pollution. Gas stovetops, unlike furnaces or water heaters, often lack direct ventilation and depend on hoods that may not capture all emissions.
“This tiny appliance punches way above its weight when compared with bigger emitters like road traffic and power plants,” said Yannai Kashtan, the study’s lead author and air quality scientist at PSE Healthy Energy. Most of the study was conducted during his time as a Stanford University graduate student.
Nitrogen dioxide, a regulated pollutant under the Clean Air Act, is a reddish-brown gas emitted by burning fuel. According to the EPA, NO2 can irritate airways, aggravate respiratory diseases like asthma, and contribute to smog formation.
For those using gas or propane for cooking, stoves contribute around a quarter of average NO2 exposure. Frequent and prolonged use can push indoor exposure to over half of total NO2 exposure.
Kashtan and his team estimated average NO2 exposure for each U.S. zip code. They measured indoor NO2 levels in over 15 cities and paired these with outdoor concentrations from across the country. The research also analyzed data from 133 million residences and occupant behavior, such as stove usage and window ventilation.
The highest NO2 contribution from stoves was in cities with smaller living spaces, offering less room for the gas to disperse.
Kashtan’s team estimates that average NO2 exposure is 24 percent lower for residents with electric stoves. Approximately 22 million Americans would fall below the WHO’s recommended NO2 limit if they ceased using gas stoves.
The American Gas Association disputed the findings. Spokesperson Emily Ellis stated the study lacks new data or epidemiological evidence linking gas stoves to asthma.
Kashtan noted that the study uniquely estimates NO2 exposure attributable solely to gas stoves. A 2023 report by the Climate Investigations Center and NPR found the gas industry knew of health risks from gas stoves as early as 1970.
The AGA refuted claims of health risks from gas appliances, citing a response to NPR. Ellis emphasized research found insufficient evidence linking gas ranges to chronic health hazards.
Ellis referenced a 2024 study in The Lancet Respiratory Medicine, stating no significant link between gas and asthma. However, the study did note increased pneumonia risk from gas use.
The American Medical Association and American Public Health Association acknowledge NO2 emissions from gas stoves as a public health concern.
Research by Kashtan indicates high gas stove usage without proper ventilation increases cancer risk due to benzene emissions.
The AGA states that gas cooking appliances are a “minor source” of NO2, with outdoor air pollution as the principal indoor NO2 source.
Kashtan is confident in separating indoor and outdoor NO2 sources in the study and reiterated that stoves are a significant source of indoor NO2 for frequent gas stove users.
Nathan Phillips of Boston University, not involved with the study, noted the findings align with known connections between gas stove emissions and respiratory health.
Dylan Plummer from the Sierra Club called for regulatory action to mitigate gas appliance risks.
Some states have taken steps to address the issue. California regulators are considering new air quality guidelines. Governor Gavin Newsom vetoed a bill mandating health warning labels on new gas stoves.
In Colorado, Governor Jared Polis signed a similar labeling requirement law, now facing a lawsuit from the Association of Home Appliance Manufacturers.
Original Story at insideclimatenews.org