The Blue Flame is a Health Risk We Can’t Ignore
The views expressed in this post are those of the author and not necessarily of CACHE leadership and its members.
Photo by KWON JUNHO on Unsplash
You might not realize it, but your gas stove is a serious hazard to your health. That familiar electric blue propane leaks a carcinogenic mix of methane, nitrogen dioxide (NO2) and other volatile organic compounds (VOCs). Breathing in these pollutants not only exacerbates asthma attacks and causes cancer but has the potential to stunt lung development in children. Researchers from the Harvard T.H. Chan School of Public Health and Central California Asthma Collaborative estimate that the mix of irritants coming from gas and propane stoves may be responsible for as many as 200,000 current childhood asthma cases. Professor Rob Jackson of the Stanford Doerr School of Sustainability notes: pollution from gas stoves is “the whole family’s problem.”
What are the main health risks associated with gas stoves?
When your gas stove is on, it releases NO2 gas and very small airborne particles called PM2.5. The World Health Organization (WHO) defines the harmful level of NO2 exposure at 5.2 parts per billion(ppb). The average NO2 exposure in homes with a gas stove is around 22 ppb according to WHO – 4 times the healthy threshold. According to Wynne Armand, MD of Harvard Medical School, almost 2 million cases worldwide of childhood asthma were estimated to be due to NO2 pollution. As explained by Professor Jackson, “Pollutant concentrations breach health benchmarks in bedrooms within an hour of gas stove use and stay there hours after the stove is turned off.” Even when gas stoves weren’t on, they leaked significant levels of methane gas. Because methane has no smell, most leaks proliferated without being noticed. Leaks typically occurred on pipe fittings located in the kitchen itself. Long-term exposure above the WHO limit to NO2, methane, and other VOCs is known to increase rates of lung cancer, heart disease, and childhood asthma.
Contribution to climate change, and developing health policy
In addition to the exacerbation of respiratory illness, natural gas stoves also contribute to global climate change. Stanford researchers have discovered that methane leaking from gas-burning stoves inside US homes has a climate impact comparable to the carbon dioxide emissions from 500,000 gas-powered cars. Home methane leaks contribute to a third as much warming as the carbon dioxide generated by combustion of the stove’s natural gas, directly exposing children and families to emissions that can trigger asthma, coughing, wheezing and other respiratory issues. It is important to note that methane and natural gas are fossil fuels, attributed to threatening air quality by increasing tropospheric ozone. Researchers at Stanford predict that methane exposure “causes an estimated 1 million premature deaths annually worldwide due to respiratory illnesses.” A gap persists between research on natural gas-burning cooking appliances compared with larger-scale natural gas pipeline leaks. Developing this research is imperative as more than 40 million American homes cook with gas and lack the ventilation needed to reduce the concentration carcinogenic indoor pollutants.
As the health and climate effects of natural gas burning gas stoves become widespread, a growing number of US cities and states have tried to ban natural gas connections and gas stoves. In doing so, lawmakers and activists have been met with pushback. During Berkeley, California’s quest to become first electrified city in the US, lawmakers passed the first natural gas ban. This effort was met with wave of controversy. In particular, the California Restaurant Association filed a lawsuit against the City of Berkeley as part of an effort to protect local restaurants from bearing the brunt of higher energy costs and energy security risks. Berkeley’s natural gas ban was overturned by a federal appeals court in April 2023.
On the other hand, federal officials have tried to encourage homeowners to swap out gas stoves for electric stoves through various financial incentives outlined in the 2022 Inflation Reduction Act. A variety of rebates were offered, from $840 full-rebates for low-income households to $420 partial-rebates for middle-income households, to encourage families to transition to cleaner electric stoves. In 2023, Richard Trumka Jr., the former US Consumer Product Safety Commissioner, previously stated that gas stoves are a “hidden hazard.” This statement and popular political discourse motivated the US Department of Energy to finalize new energy efficiency standards for gas and electric stoves to be put in effect January 2028. The new standards would require a small portion of stove models to make improvements to their energy efficiency, which were projected to save Americans around $1.6 billion on their utility bills over 30 years. However, the US federal appeals court set aside the Department of Energy’s new efficiency standards after states filed adverse comments.
How to protect yourself against indoor carcinogens
Photo by Annie Spratt on Unsplash
While discourse regarding gas stoves still stands, significant legislation addressing adverse health and climate impacts has yet to pass. To mitigate your exposure to carcinogenic indoor pollutants emitted from gas stoves, pay close attention to the size of your house and kitchen, and monitor your time spent in the kitchen. Smaller kitchens concentrate NO2 and methane, elevating exposure. As you cook, prioritize ventilation by turning on your range hood exhaust, or using an air purifier post-cooking. You can even crack open the window! The most effective way to mitigate risk is to switch out your gas stove with an electric. If that isn’t possible, Magali Blanco, PhD, assistant professor in the Department of Environmental and Occupational Health Sciences at the University of Washington suggests using more electrical appliances such as a kettle, microwave or pressure cooker to lower NO2 gases.
Making the switch to electric or simply increasing kitchen ventilation are both great ways to mitigate exposure to NO2, methane, and VOCs released from your gas stove. Before switching to full electric, consider a single burner induction as an “in-between” before a full switch from gas to electric. Induction cooktops do not have any open flames, generating heat directly into the pan unlike gas stovetops. A gas burner loses 50-60% of its heat to the surrounding air before heating a pan, with larger stoves emitting higher rates of nitric oxides. On the other hand, induction stoves produce zero combustion gases, saving you and your family from unwanted carbon monoxide and nitrogen dioxide gas waste. Taking measures to reduce your exposure to carcinogenic pollutants is imperative as you protect you and your family’s health. Through integrating strategies to mitigate gas exposure, you can help lessen indoor air pollution and decrease global greenhouse gas emissions.
