Technician Colin Finnegan sampling pipeline gas from a stove in Menlo Park, Calif. Credit: Rob Jackson, Stanford University
Key points:
- Researchers showed gas stoves and ovens emit high levels of benzene
- Emissions were 10-50 times greater than those from electric stoves
- Benzene pollution is associated with blood cell cancers
A study by Stanford researchers found that gas stoves and ovens release high concentrations of benzene in homes. Benzene exposure has been linked to blood cell cancers including leukemia.
Experiments revealed that indoor concentrations of benzene emitted from flames in gas stoves can be higher than those in secondhand smoke, and are 10-50 times greater than emissions from electric stoves. Additionally, the authors found that benzene can drift to other rooms far from the kitchen and that residential range hoods are not always effective at reducing exposure.
Further tests showed that food such as salmon and bacon emit no benzene during cooking, demonstrating that all emissions come from gas combustion rather than cooking food. The researchers also detected zero benzene emissions from induction cooktops.
The study, published in Environmental Science & Technology, is the first to analyze benzene pollution from gas stoves and ovens in use. Previous Stanford-led research focused on the leaking of unburned gas from cooking appliances when they are turned off, which results in methane emissions with a climate impact comparable to carbon dioxide emissions from 500,000 gasoline-powered cars. These gas leaks also expose residents to nitrogen dioxide, which can trigger respiratory diseases like asthma.
However, gas combustion emits benzene concentrations hundreds of times greater than those found in unburned gas, according to the researchers.
“Benzene forms in flames and other high-temperature environments, such as the flares found in oil fields and refineries,” said senior author Rob Jackson, a professor of Earth system science at the Stanford Doerr School of Sustainability. “We now know that benzene also forms in the flames of gas stoves in our homes.”
In order to curb the health risks associated with gas stoves, the researchers recommend using induction cooktops and electric kitchenware when possible, and taking advantage of rebate and tax credit programs to offset the cost of replacing gas appliances.