Recently I’ve found myself embroiled in debate about the effects of indoor air pollution on children’s health, particularly with regard to the use of unventilated gas stoves for cooking. It’s easy to be dismissive of the subject, because, after all, many of us have grown up around gas stoves or polluted environments and are still around to talk about it. And because this is a topic only lightly explored until the past decade, you might find it subject to skepticism or dismissed as excessive concern over a seemingly trivial matter.
The science however suggests strongly otherwise. Particularly if you are a parent, I urge you to consider the following excerpts and citations on the subject before forming any opinion. Because the quality of the sources are important, I’ve provided the citations inline. Most everything herein is from peer-reviewed research journals or summaries thereof, and has been cited in turn by many larger pollution and environmental studies.
In making this brief compilation for my own use, I realized it would be helpful to pass it along for the benefit of others. Some relatively small changes around the home, such as installing a vented range hood with outdoor exhaust, would clearly be worth the investment in the protection it affords your child.
Scope of the Hazard
First, from a New York Times interview of a Berkeley Lab engineer, let’s get an idea of the size of the problem relative to other concerns:
“Emissions of nitrogen dioxide in homes with gas stoves exceed the Environmental Protection Agency’s definition of clean air in an estimated 55 percent to 70 percent of those homes, according to one model; a quarter of them have air quality worse than the worst recorded smog event in London. Cooking represents one of the single largest contributors, generating particulate matter … at concentrations four times greater than major haze events in Beijing.
“Because we’re used to the smell, we don’t think of it as an issue,” said Jennifer M. Logue, 32, an air quality engineer at the Berkeley Lab. “When you live in a small building, you cook a lot and don’t use your range hood … then you’re probably going to have a problem with pollutants from cooking.”
Recently Dr. Logue estimated the long-term health effects expected from hundreds of chemicals found in average homes. Her 2012 study, published in Environmental Health Perspectives, used a common epidemiological metric known as disability-adjusted life-year to show that the population-wide health impact of indoor pollutants is on a par with that of car accidents, and greater than that of traditional concerns like secondhand smoke or radon.
“It’s well over violence,” she said. “It’s not a small risk.”
“Emissions from gas stove burners can reach potentially harmful levels if the cook does not use a venting hood. … The model predicted that when homes did not use venting range hoods, household exposures frequently exceeded benchmarks the authors set based on federal and state health-based standards.” “Clearly we have unhealthy situations indoors since we exceed outdoor standards in homes.”
“Cooking Up Indoor Air Pollution: Emissions from Natural Gas Stoves” https://ehp.niehs.nih.gov/doi/10.1289/ehp.122-a27 (National Institutes of Health, 2014).
It’s also worth noting that pollutant types vary by type of food and cooking method to the extent that baking, broiling, or roasting can even exceed emission levels brought about by frying.
https://www.arb.ca.gov/research/indoor/cooking/0-Cover-TOC-Exec-Summary.PDF (California Air Resources Board, 2001).
Asthma and Respiratory Issues
“In homes where a gas stove was used without venting, the prevalence of asthma and wheezing is higher than in homes where a gas stove was used with ventilation,” said Ellen Smit, an associate professor in the College of Public Health and Human Sciences at OSU and one of the study’s authors. “Parents of all children should use ventilation while using a gas stove.” (emphasis added). Specifically, where “ventilation such as an exhaust fan was used when cooking”, children were less likely to have asthma, bronchitis, and wheezing, by 32%, 38%, and 39% respectively.
“Childhood asthma linked to lack of ventilation for gas stoves.” www.sciencedaily.com/releases/2014/09/140929180523.htm (Oregon State University via ScienceDaily, 2014).
“In homes that used gas stoves, children whose parents reported using ventilation when operating their stove had higher lung function and lower odds of asthma, wheeze, and bronchitis.”
“A cross-sectional study of the association between ventilation of gas stoves and chronic respiratory illness in U.S. children enrolled in NHANESIII” https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-13-71 (Environmental Health, 2014).
Raised White Blood Cell Counts
“The strongest effect estimates for chronic inflammation were found for those children likely to have been exposed at higher levels, that is when stoves had no fans, in smaller homes, and for children spending more time indoors.” (Obviously children in colder climates are at greater risk.)
“Gas cooking, respiratory health and white blood cell counts in children”. https://www.sciencedirect.com/science/article/pii/S143846390470005X (Science Direct, 2000).
Effect On Mental Development
“Gas cooking was related to a small decrease in the mental development score compared with use of other cookers independent of social class, maternal education, and other measured potential confounders. This decrease was strongest in children tested after the age of 14 months and when gas cooking was combined with less frequent use of an extractor fan.” (emphasis added)
“Indoor air pollution from gas cooking and infant neurodevelopment.” https://www.ncbi.nlm.nih.gov/pubmed/22082993 (NIH, 2014).
Less Studied Harms
Nitrogen dioxide is one of the main pollutants from gas stoves, which is also one of the primary components of traffic pollution. A multitude of recent studies have linked children’s exposure to nitrogen dioxide to increased incidence of everything from autism, behavioral and mental health issues, and later in life, Alzheimer’s.
See generally, “Air pollution and detrimental effects on children’s brains. The need for a multidisciplinary approach to the issue complexity and challenges.” https://www.frontiersin.org/articles/10.3389/fnhum.2014.00613/full (Frontiers in Human Neuroscience, 2014).
“Childhood autism spectrum disorders and exposure to nitrogen dioxide, and particulate matter air pollution: A review and meta-analysis.” https://www.sciencedirect.com/science/article/pii/S0013935116303176 (Environmental Research, 2016).
What Experts Recommend
“The burden of asthma associated with gas stoves could be reduced … were all homes with gas stoves fitted with high efficiency range hoods that vented outdoors.”
https://www.mja.com.au/journal/2018/208/7/damp-housing-gas-stoves-and-burden-childhood-asthma-australia (Medical Journal of Australia, 2018).
“The first tip is to ventilate when you cook, and to ventilate more the more you cook. Range hoods are the most effective way to do this, if your range hood actually moves air out of the kitchen. If you have a range hood that just recirculates air back into the kitchen, you need to use another exhaust fan — for example, from a nearby bathroom — or open windows. You also need to use your hood or exhaust fan regularly. Based on several surveys, many people only occasionally use them.”
https://scopeblog.stanford.edu/2018/03/06/use-your-range-hood-for-a-healthier-home-advises-indoor-air-quality-researcher/ (SCOPE, Stanford University, 2018).
“It’s also important to select an effective range hood, use the vent on its highest setting, and to cook on the back burners when possible.”
The self-cleaning cycle of the gas stove produces the “highest pollutant levels by far”. “Use the self-cleaning oven cycle only when the house is not occupied and is well ventilated, especially during the first hour or two.”
https://www.arb.ca.gov/research/indoor/bcooking.pdf (Air Resources Board, 2001).
We are bombarded with info from more sources than ever, and it’s certainly not possible to be fully aware of every health-related development. While indoor air pollution awareness is relatively new, it’s also not based on the latest “study du jour”; it’s established science now. And if you’re a parent aware of this hazard, it’s not even an “err on the side of caution” rationale behind considering what changes might be in order in your home — rather, as with any baby-proofing checklist, it’s incumbent on you to do so.