Poorer Americans and racial and ethnic minority groups are disproportionately exposed to harmful gas stove pollutants, scientists at Stanford University, Harvard University and the Central California Asthma Collaborative found.

Previous studies have shown gas stoves emit nitrogen dioxide and carbon monoxide — pollutants that can cause respiratory issues — at levels deemed unsafe by the US Environmental Protection Agency and the World Health Organization. The new findings in Science Advances are the first to measure gas stove nitrogen dioxide (NO2) pollution across home types, race, income and cooking habits, and then calculate the cost of preventable childhood asthma cases.

To conduct the study, the researchers constructed a model to estimate gas stove NO2 concentrations combining a federal indoor air quality model with field measurements collected from over 100 homes of varying sizes in five US states. They then applied their model to 7,632 houses with gas, propane and mixed-fuel stoves included in the US Energy Information Administration’s 2020 Residential Consumption survey. After dividing those homes into 24 distinct groups based on floor plans ranging from studios to multi-bedroom homes, they estimated the intensity of NO2 exposure.

The researchers found that American Indian and Alaska Native households face the most long-term exposure to NO2, at levels 60% greater than the national average. Black, Hispanic and Latino households follow, suffering 20% more exposure than the average. Stoves alone expose each of these groups to more NO2 pollution than is safe, according to WHO.

Households making under $10,000 per year experience double the exposure to gas stove pollution compared to households making more than $150,000, the study found. The race- and income-based disparities are due in part to differences in home size. However, the scientists noted there could be other relevant factors not measured in their model, including social differences in cooking behavior, ventilation and time spent indoors. 

Using established epidemiological relationships, the researchers also estimated that gas and propane stoves contribute to as many as 19,000 adult deaths annually in the US, as well as 200,000 childhood asthma cases and $1 billion in societal harm.

“Most of us spend 90% of our time or more inside,” said Rob Jackson, professor of earth system science at the Stanford Doerr School of Sustainability and the study’s principal investigator. “We need to take ownership and act to clean up people’s air because it’s the air most people breathe and we’ve ignored it for decades.”

Annie Carforo, climate justice campaigns manager at the Manhattan-based group WE ACT for Environmental Justice, said the findings are in line with what the group observed during a study of gas stove pollution in New York City public housing. She said people of color and low-income individuals are more likely to live in smaller, older apartments that have poor ventilation, ineffective or broken range hoods and dated appliances that leak more gas. 

“This is a massive injustice that builds on itself, and that’s why you see much higher rates of asthma in communities of color and low-income communities,” Carforo said. She added that the new research “gives us more leverage to call for interventions and programs and policies that are going to intervene in low-income households first.”

The study’s authors said removing gas and propane stoves is the best solution for individuals. Those who cannot afford an immediate replacement or do not have the option as renters can buy a portable induction burner, use an air filter, open windows when they cook and use range hoods that circulate the kitchen air outdoors. But they also acknowledged cost can be a barrier.

While tax credits in the Inflation Reduction Act can help reduce the price of an electric stove, the researchers said stronger regulations are needed to help households switch and keep gas out of new buildings. Gas stove bans have fueled a culture war in the US, though.

“Our biggest problem is the political unreality of the whole situation,” said Kevin D. Hamilton, a registered respiratory therapist and senior director of government affairs at the Central California Asthma Collaborative. “All we can do is hope that researchers provide as much hard data as we possibly can to get some sanity into the conversation.”