09-05-2025
- Health
- San Francisco Chronicle
Gas stoves nearly double children's cancer risk, Stanford study shows
A new study from Stanford University found that children living in homes with frequent gas stove use and poor ventilation face nearly twice the lifetime cancer risk from benzene exposure compared to adults.
The study, published in the Journal of Hazardous Materials, is the first to evaluate cancer risks from benzene generated during gas stove combustion and to estimate leukemia cases attributable to these emissions.
Researchers measured benzene levels in 87 homes across Colorado and California, simulating a range of cooking scenarios. They then modeled how the chemical spreads through different types of housing.
Benzene, a known carcinogen also found in gasoline and cigarette smoke, is released during the use of natural gas or propane stoves.
The findings showed that children's lifetime cancer risk from this exposure is 1.85 times higher than that of adults.
'Children generally breathe faster and take in more air — and therefore more pollutants — relative to their smaller body size,' the researchers noted.
Risk levels were highest in smaller residences, such as apartments and manufactured homes, where benzene concentrations were found to travel from kitchens into living spaces and bedrooms, areas where people spend the most time.
In worst-case scenarios involving poorly ventilated homes and the highest-emitting stoves, children's lifetime cancer risk ranged from 1.92 to 12.03 cases per million. Adults in similar conditions faced risks between 0.94 and 5.89 per million, both well above the World Health Organization's benchmark of one in a million.
The act of igniting a gas stove releases other harmful chemicals, including nitrogen dioxide, a respiratory irritant that has been linked to higher rates of childhood asthma.
While using high-efficiency vent hoods or opening windows can reduce exposure, the study found that ventilation alone does not fully eliminate the risk.
'This study underscores the importance of effective ventilation and highlights the need for policies and strategies to mitigate benzene exposure from gas stoves, particularly for vulnerable populations such as children,' the authors said.
Roughly 40% of U.S. households — and more than 70% of California households — use a natural gas cooking appliance, according to a 2023 estimate from the U.S. Energy Information Administration.
Growing concern over health and environmental impacts has prompted action in several states. In California, lawmakers passed AB2513 last year, which would have required warning labels on gas stoves sold in stores starting in 2026. Gov. Gavin Newsom, however, vetoed the bill.
The measure was intended to expand upon Proposition 65, California's landmark toxic chemical disclosure law passed in the 1980s, which mandates warnings on products that may cause cancer, birth defects or reproductive harm.
Previous research has linked gas stove usage to increased risks of childhood asthma, and one 2023 Stanford study found that gas stoves can emit benzene at levels higher than secondhand cigarette smoke.
California has taken further steps to curb pollution from gas appliances, including a plan to ban the sale of gas heaters by 2030.
Local efforts, such as Berkeley's ordinance banning natural gas hookups in new buildings, have faced legal challenges. A federal court ruled the Berkeley law conflicted with national regulations, prompting the city to repeal the ordinance.
