Cooking with gas indoors has been linked to 12.7 percent of all childhood asthma cases in the United States, a new study has found, comparing its effect on health to that of second-hand smoking.
The research prompted calls, including from US Energy Secretary Jennifer Granholm, for more Americans to use electric and induction stovetops, as well as criticism from the gas lobby.
Around 35 percent of American kitchens have gas stovetops, which previous research has shown have higher levels of nitrogen dioxide that has in turn been linked to higher asthma rates.
The environmental think tank Rocky Mountain Institute (RMI) led the peer-reviewed study, which was published last month in the International Journal of Environmental Research and Public Health.
The study's lead author Talor Gruenwald, a data scientist at electrification advocacy group Rewiring America, said the findings suggested that around 650,000 children in the US "are suffering from asthma who might not otherwise if they weren't exposed to gas stoves".
Pointing to a comparable asthma risk from second-hand smoke, he told AFP that "using a gas stove is pretty much like having a smoker living in your home".
The study used the same method as 2018 research which attributed 12.3 percent of childhood asthma in Australia to gas stoves.
It used a 2013 meta-analysis of 41 previous studies to determine the risk of asthma for children in homes with gas cooking, and combined that information with 2019 census data from nine US states.
- Growing calls for action -
The American Gas Association, a lobby group, lashed out at the study as an "advocacy-based mathematical exercise that doesn't add any new science".
The group said in a statement that the study's "authors conducted no measurements or tests based on real-life appliance usage, emissions rates, or exposures."
Gruenwald dismissed the lobby's statement as a "boilerplate response" that did not point to any research that might challenge their findings.
The study comes amid growing calls in the US for action on the hazards of gas cooking.
"We can and must FIX this," Energy Secretary Granholm tweeted in response to the study.
She added that President Joe Biden's giant Inflation Reduction Act "would give Americans greater access to electric and induction cooktops".
Last month a commissioner from the US Consumer Product Safety Commission said that his agency would issue a formal request for information from the public on the hazards of gas cooking.
The commissioner, Richard Trumka Jr, said in a video that "we ought to keep the possibility of a ban in mind".
Twenty Democratic Senators, including Elizabeth Warren and Bernie Sanders, also signed a letter last month calling on the agency to take action on the issue.
Asthma is the most common chronic disease among children, affecting an estimated 262 million people globally and causing 455,000 deaths in 2019, according to the World Health Organization.