Unburned gas leaking from kitchen stoves contains at least 21 hazardous air pollutants, according to a study by researchers at Harvard and Boston Universities published this morning in the journal Environmental Science & Technology. The EPA-defined hazardous air pollutants the researchers identified include benzene, toluene, ethylbenzene, xylene, and hexane. “We found that unburned natural gas delivered to homes contains numerous air toxics … that can cause cancer and other serious health effects,” lead author Drew Michanowics told the Boston Globe.

The researchers also found that gas leaks are often undetectable by smell to people living in homes with gas stoves, and that these leaks are unaccounted for in state or federal pollution inventories, suggesting a threat to both public health and the climate. The Boston study builds on research published in January by Stanford scientists, which found that gas stoves leak significant amounts of methane, including when the stoves are turned off, and on a 2020 analysis showing that gas stoves are a significant contributor to childhood asthma, and likely exposing tens of millions of Americans to air pollution levels that would be illegal if they were outside. (Boston Globe $, New York Times $, Stat, The Hill, Inside Climate News, WBUR, AirQualityNews.com)