One reason the debate over cooking pollution is so murky and easily confused is that cooking of any kind produces some pollutants that are harmful if not properly handled. Applying heat to food produces particles — tiny particles (PM10, or particulate matter 10 micrometers in diameter), tinier particles (PM2.5, or 2.5 micrometers in diameter), and even tinier “ultrafine” particles (100 nanometers in diameter) — that can exacerbate respiratory problems.
All cooking should be done in a properly ventilated space, and if your nose warns you something is up, you should open a window. Common sense is your guide.
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For one thing, even in the absence of any food, gas combustion produces PM2.5 (one of the deadliest air pollutants) — research suggests gas cooking produces about twice as much PM2.5 as electric. It also produces nitrogen oxides (NOx), including nitrogen oxide (NO) and nitrogen dioxide (NO2), carbon monoxide (CO), and formaldehyde (CH2O or HCHO). All of these pollutants are health risks if not properly managed.
CO is an invisible, odorless gas that, at high enough concentrations, causes dizziness, headaches, fatigue, disorientation, and eventually death. (In the US, 27 states require CO monitors by law.) Though research has found that the presence of gas stoves in the home is one source of elevated risk of CO poisoning, that generally only happens when something goes wrong: a gas stove with a pilot light, a poorly ventilated space, a burner left on, something like that. Among average people, symptoms start at around 70 parts per million (ppm).
