A new study has found that using gas stoves can raise indoor benzene concentrations to levels exceeding those from secondhand smoke or even those found near oil and gas facilities. The research, published in a peer-reviewed journal and led by Stanford University scientists, measured benzene levels in 87 homes in California and Colorado.
Leaving a single gas hob on for 45 minutes increased benzene levels above benchmarks set by the World Health Organization and the US Environmental Protection Agency. Emissions from gas and propane stoves were 10 to 25 times higher than those from electric coil stoves, while induction stoves emitted no benzene at all. Even low-burning hobs or gas ovens released significant amounts of the chemical.
Benzene is a known carcinogen linked to lymphomas and leukaemia, damaging bone marrow even at low doses. The study found that elevated benzene levels can linger for up to six hours throughout a home after the stove is turned off. Jan Kirsch, an oncologist based in California, described benzene as a “very potent” cause of blood cell cancers, adding that people have likely died from exposure in their homes.
More than a third of US households use gas stoves, but many lack adequate ventilation. Range hoods often recirculate air rather than expelling pollutants, leading to indoor air hazards that rival outdoor pollution. Rob Jackson, a Stanford scientist and co-author, noted that gas stoves are the only common fossil fuel appliance that vents pollution indoors.
The findings add to decades of research highlighting dangers from gas stove emissions, including carbon monoxide and formaldehyde. A previous study linked gas stoves to over 12% of childhood asthma cases in the US. The Biden administration has proposed efficiency standards for new stoves, but around half of current models would fail. Some states, like New York, are phasing out gas appliances in new buildings, sparking political backlash from Republicans who oppose any ban.
