University of Saskatchewan chemist says it might be the time to let go of gas stoves

Gas stoves became the latest inflection point in the culture war this week after a U.S. study linked them with an increased risk of asthma in children.

"The study suggested almost 13 per cent of all childhood asthma cases can be attributed to gas stove use, which is a lot," said Tara Kahan, a chemist at the University of Saskatchewan chemist.

"It seems obvious that gas stoves should be going away."

The peer-reviewed study, published in the International Journal of Environmental Research and Public Health, added fuel to the budding debate over the potential threats that gas stoves pose to public health.

Kahan has been involved in previous study of what gas stoves do to their environment. In 2017 and 2018, she took pollution readings inside homes that had used a gas stove. She and her colleagues were surprised by how high the levels of nitrogen oxides were and how long they lasted.

Exposure to nitrogen oxides, produced when gas is burned, is linked to respiratory problems such as asthma and decreased lung function, especially in children. A 2013 meta-analysis of 41 studies found that children living in a home that used gas for cooking had a 42 per cent increased risk of having asthma.

Kahan's measurements found that not only did the pollutants often linger for a couple of hours, but also that the levels of nitrogen oxide pollutants sometimes exceed Health Canada guidelines for a one-hour exposure.

In December, a member of the Consumer Product Safety Commission, an agency entrusted with protecting the public from potentially dangerous household products in the U.S., said that the commission will consider regulating indoor air pollution from gas stoves, including imposing a possible ban.

This soon riled many in Washington, particularly Republicans who supported gas stoves, a staple in millions of U.S. kitchens. Presently, the American regulators have no plans to ban gas stoves.

"The levels of nitrogen dioxide in our lab is 24 parts per billion, which is well below the 90 parts per billion as suggested by Health Canada," Kahan, an associate professor and Canada Research Chair in environmental analytical chemistry, said.

"But if we had a gas stove in the lab for example, those levels would go up and quite possibly exceed those limits."

Kahan said nitrogen dioxide can be associated with making respiratory diseases like asthma worse and, especially in children, can trigger asthma if there is a prolonged exposure.

She said multiple studies have shown levels of nitrogen dioxide produced by gas stoves exceed, Health Canada guidelines, in some cases by many times.

She has personally applied the knowledge to her own life by switching from a gas stove to electric induction, and advises others to do the same.

"Our instruments measured every 10 seconds, so we could see levels from being nice and flat to suddenly really high. It's almost like seeing the air change colours. That's really gross."

According to SaskEnergy, there are approximately 18,800 gas stoves or ranges in Saskatchewan – the equivalent of about four per cent of all stoves/ranges in the province.

"According to Health Canada, cooking on an electric or gas stove can affect indoor air quality. Ventilation is the easiest and most effective way to mitigate the impact," the utility company said in a written statement.

SaskEnergy said a properly installed range hood can reduce exposure to cooking-related pollutants by more than 80 per cent.

Kahan said kitchen spaces should be equipped with range hoods that vent to the outside, instead of recirculating the unhealthy air inside.