A recent controversy has emerged over the use of the gas stoves. Gas stoves are present in roughly 1/3 of United States homes and it has been observed that there may be an increased risk of asthma in children and other respiratory health risks linked to indoor air pollution from these appliances. A study published in the Journal of Environmental Science and Technology in October 2022, found that gas stoves can emit low levels of methane, carbon monoxide, formaldehyde and benzene. Two further lung irritant substances emitted from gas stoves are nitrogen dioxide and tiny airborne particles known as PM2.5 – both of which are lung irritants. 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.[i]
For a more in depth analysis of all of the indoor pollutants and the levels at which they produce health effects please see this VOX news article written by David Roberts.
In a further study published December in the International Journal of Environmental Research and Public Health, postulated that more than 12% of current childhood asthma cases in the U.S. can be linked to the use of gas stoves.
The controversy is made worse by the fact that these low levels can emit even when the stove is not in use. Given that people in the U.S. spend on average roughly 90 percent of their time indoors. With Covid -19, the average time spent indoors may be much higher.[ii]
Thus, we do most of our breathing inside but very little attention or regulation standards govern indoor air quality. Outdoor air is the subject of massive legal and regulatory legal wranglings going back decades. The six common air pollutants covered by the U.S. Clean Air Act — ground-level ozone, particulate matter, carbon monoxide, lead, sulfur dioxide (SO2), and nitrogen dioxide (NO2) — have fallen an average of 74 percent since the Act was passed in 1970.
This is a good thing, because a growing body of research suggests that those pollutants are even more harmful to humans, at lower exposures, than previously believed.
But the more ominous news is that the Environmental Protection Agency (EPA) warns that “studies of human exposure to air pollutants indicate that indoor levels of pollutants may be two to five times — and occasionally more than 100 times — higher than outdoor levels.”
Despite those risks, there are no federal standards or guidelines governing indoor pollution. A patchwork of state and local standards in the U.S. protects consumers, inadequately.[iii]
According to a David Roberts, four research and advocacy groups — the Rocky Mountain Institute, Mothers Out Front, Physicians for Social Responsibility, and the Sierra Club — released a literature review, assessing two decades worth of peer-reviewed studies. They find that “gas stoves may be exposing tens of millions of people to levels of air pollution in their homes that would be illegal outdoors under national air quality standards.” Like most issues involving health and environmental toxicants, the pro- lobbying groups, in this case the natural gas companies, have fought long and hard to fend off any regulatory standards being applied.
The controversy of a gas cooking health hazards began almost 50 years ago when researchers in England and Scotland showed that 5000 children were linked to a positive correlation between gas cooking and asthma symptoms. Since then, a slew of new studies has been published.
Use of a high-efficiency range hood that extracts indoor air contaminants and carries them outside appears to be of benefit. Opening windows may be of help and using a HEPA air filter ( which, if it extracts particles below 0.3 microns, will be of help in removing mold particles as well) may also be of use.
Environmentalists believe that switching to electric induction cooking is an important climate step. this is furthered by the awareness that there are cooking benefits to electric stoves- they allow you to cook faster. Chefs have commented that making the switch to induction may help increase production and improved employee mental health because the kitchens are not as hot as when using gas stoves.
It has been postulated by certain media outlets that U.S. federal regulators are considering a ban on gas stoves but the U.S. Consumer Product Safety Commission (CPSC) has commented that it is still figuring out the best way to tackle this issue. The CPSC are considering all approaches to regulation and has commented that any action would be a very lengthy process, implying that there are no eminent policy changes in the near future. It appears that the most likely move will be that, instead of having people physically remove gas stoves, the CPSC will require that new products comply with its regulations. This would mean that new homes be built with electric stoves or high-efficiency exhaust vents.[iv]
However, a very sensible article was written in Medscape by F. Perry Wilson Jan 24 2023[v] titled “The Gas Stove Debate Hinges on One Bad Word”. Here he points out the difference between association and causation. He makes the point, through deductive reasoning and math, that if all gas stoves were to be removed, there would very likely not be a reduction in the amount of asthma systems in children by 12%. The word “attributable” is the key word in his argument, bringing into focus the age-old conundrum of “association (or correlation), in studies, does not imply causation.” There are a host of other factors that may be playing a role in the gas -stove/asthma debate, such as the economics and living conditions of those with gas stoves versus those without. There are multiple causes of asthma.
As always, an open mind is required when drawing conclusions about many studies that are published these days. There are too many factors that come into play when attempting to make up one’s mind about conclusions reached such as these. See my blog on evidence-based studies for further insights to the limitations of certain publications here.
[iv] Time Magazine Jan 30th 2023.
[v] The Gas Stove Debate Hinges on One Bad Word (medscape.com)
Dr. Bruce Hoffman, MSc, MBChB, FAARM, IFMCP is a Calgary-based Integrative and Functional medicine practitioner. He is the medical director at the Hoffman Centre for Integrative Medicine and The Brain Centre of Alberta specializing in complex medical conditions. He was born in South Africa and obtained his medical degree from the University of Cape Town. He is a certified Functional Medicine Practitioner (IFM), is board certified with a fellowship in anti-aging (hormones) and regenerative medicine (A4M), a certified Shoemaker Mold Treatment Protocol Practitioner (CIRS) and ILADS trained in the treatment of Lyme disease and co-infections. He is the co-author of a recent paper published by Dr. Afrin’s group: Diagnosis of mast cell activation syndrome: a global “consensus-2”. Read more about Dr. Bruce Hoffman.