Researchers have estimated that around 12-13% of childhood asthma cases in countries like Australia and the United States can be attributed to the use of gas stoves for cookingSource: Nationalasthma.org.au
*Stanford University researchers measured emissions for 53 stoves while on and off. *
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Seventy-six percent of unburned methane leaked out through pipes and fittings when stoves were off.
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A gas stove also pollutes when it is off. A 2022 study found that gas stoves, even when not in use, can leak as much benzene, a carcinogen, as secondhand cigarette smoke. Another study that analyzed natural gas samples found that 95 percent of them contained benzene, for which there is no safe level. That study also found 21 hazardous air pollutants in unburned gas, including hexane and toluene, which can affect the nervous system, liver, and kidneys.