Gas stoves raise indoor levels of cancer-causing benzene, study finds

Using gas-powered stoves and ovens can raise the levels of the cancer-causing chemical benzene in a home, according to a new study. 

The study, published in the journal Environmental Science and Technology, looked at 87 stoves in California and Colorado. Researchers found that gas and propane stoves and ovens emitted significantly more benzene than electric alternatives. 

Long-term exposure to benzene can cause blood cancer, according to the Centers for Disease Control and Prevention. Gas stoves have previously been found to leak benzene and have also been linked to childhood asthma. 

Whether to regulate gas-powered appliances has been a topic of debate in Washington, particularly after one regulator floated a ban earlier this year. Many Republicans have been particularly staunch advocates against bans or regulations on gas stoves, while the White House has also said that it opposes a ban.

Looking at a subset of 17 homes with 33 distinct burners or ovens, the researchers found that setting the gas or propane burners on high or the ovens to 350 degrees Fahrenheit for 45 minutes raised benzene levels in all kitchens.

They also found that in 29 percent of cases — judging each burner or oven as an individual case — kitchen benzene concentrations were found to be above the chemical levels found in secondhand tobacco smoke. 

That’s not to say that the health impacts are the same as secondhand smoke, however, since tobacco has a different makeup. Tobacco smoke contains a number of other carcinogens such as arsenic and formaldehyde. 

Nevertheless, lead author Yannai Kashtan said that the findings do suggest that there could be an elevated cancer risk.

“If you’re breathing in benzene you’re at an elevated risk,” said Kashtan, a graduate student at Stanford’s Doerr School of Sustainability. “The World Health Organization says that from a cancer point of view there is no totally safe level of exposure.”

The study also looked at bedrooms in six of the homes. After setting ovens to 475 degrees fahrenheit for 90 minutes and measuring for several hours afterwards, the researchers found elevated concentrations also in the bedrooms. 

Asked for comment, a leading gas industry group said that it is reviewing the study. 

“As we have with every study related to the use of natural gas and the health and safety of customers and communities, we are taking the time to evaluate this study to understand its methodology and the merits of its findings,” said Karen Harbert, CEO and president of the American Gas Association, in a written statement. 

“Customers deserve access to transparent information and sound science to help make decisions about the health and safety of their families, and the natural gas industry continues to contribute objective, thorough and meticulous scientific analysis,” Harbert added.