What’s in the gas?
Gas stoves have long become popular in many countries, with the advantage that they can be used even in the event of a power outage and are suitable for cooking at high temperatures. You just need to turn it on and the flare can be easily adjusted. But gas produces a wide variety of byproducts, some that are relatively benign and some that are not too benign to human health.
The natural gas supplied to appliances such as gas stoves is almost entirely methane, with trace amounts of other hydrocarbons such as ethane, some nitrogen and carbon dioxide (CO₂). Natural gas has a very good combustion effect, as you can see from a blue, smoke-free flame on the stove top. Combustion releases CO₂ and water, along with traces of other gases.
For every 1,000 grams of CO₂ produced by burning natural gas, 34 grams of carbon monoxide, 79 grams of nitrogen oxide and 6 grams of sulfur dioxide are released. Some studies have found that formaldehyde is also released, but there aren’t any studies that show how much of it is.
The gas also releases tiny soot particles, commonly known as PM2.5 (matter particles less than 2.5 micrometres in diameter). Cooking with a gas stove produces twice as much PM2.5 as an electric stove. However, gas is clearly much cleaner than coal. Coal burning typically produces 125 times more sulfur dioxide than gas, and about 700 times the PM2.5 level.
There is a link with childhood asthma
However, while gas stoves are much less polluting than coal stoves, some emissions can still accumulate indoors and have the potential to have a significant effect on health. Nitrogen dioxide and PM2.5 particles in particular have adverse effects on health. PM2.5 particles can go deep into the lungs, and the toxins carried on them are absorbed into the bloodstream.
It is not clear whether gas stoves are the cause of significant health problems, given the fact that households have many other potential sources of pollution in their homes. Many homes use gas heaters, which generate the same emissions as stoves, or have multiple sources of formaldehyde in addition to burning natural gas (such as furniture, adhesives, and carpets). .
However, because nitrogen dioxide and the PM2.5 particles have a marked effect on respiration, a large amount of research has been directed towards asthma.
Evidence shows that use of gas stoves is linked to an increased risk of asthma in children.
First, the effects of gas stoves on asthma in adults are not clear.
But there is clearer evidence of effects on children’s health. A population study in the Netherlands found that cooking with gas is linked to an increased risk of asthma in children. This study uses meta-analysis, a form of statistical analysis that combines the results of multiple scientific studies to improve the detection of associations. The authors concluded: “Tliving in a home with a gas stove increases the current risk of asthma by 42%, a 24% increase in the lifetime risk of asthma and a 32% increase in the risk of asthma both now and in life.
Another US study found that gas stoves increase indoor nitrogen dioxide levels and increase the likelihood of children with asthma using an inhaler at night. But the paradox is that there is no increase in asthma symptoms. A 1980 study of children in six US cities found a strong association with indoor smoking and respiratory problems, but no association with gas stove use.
But an Australian study in the Latrobe valley, where 80 households with children between the ages of 7 and 14 years old, found an association between gas stove use and asthma. Children in households with gas stoves are twice as likely to be diagnosed with asthma as children from households without gas stoves. However, this study cannot show whether use of gas stoves causes asthma. The authors suggest that exposure to nitrogen dioxide may increase susceptibility to allergens.
In 2018, another study in Australia, the country with the highest prevalence of asthma in the world, determined that 12.3% of children here have asthma, possibly due to exposure to gas stoves. However, the results of this analysis cannot conclude whether exposure to gas stoves inevitably causes asthma or exacerbates existing cases.
How to reduce risk?
Almost certainly, good ventilation will reduce the levels of nitrogen dioxide and PM2.5 particles in your home.
Most modern homes are better insulated than shabby homes, but better insulation means more indoor pollutants build up. Fortunately, many modern homes also have modern kitchens with hoods. If properly installed, this will reduce the amount of nitrogen dioxide and PM2.5 particles.
When used, a hood can be effective in reducing particles released from gas cooking.
A 2018 study on the popularity of gas cooking in Australia found that using a high efficiency hood can reduce the risk of asthma in children due to gas stoves from 12.8% to 3 , 4%. However, the report also shows that 44% of people in the city of Melbourne who own a hood do not use them regularly.
Even if you don’t have a hood, improving natural indoor airflow will not only reduce products from gas burning, which is associated with asthma, but also reduce pollutants. Other in the family and bring benefits to overall health.
And when it’s time to change the stove, consider a non-gas device as it will have less of an impact on your health and reduce your family’s carbon footprint.