How cooking with gas releases harmful air pollution in the home

Nitrogen dioxide, normally associated with diesel exhausts, is among pollutants released by using gas cooker and hob

The transition away from gas cooking envisaged by the UK’s Climate Change Committee will mean big improvements to air pollution in many homes.

Most of us spend about 90% of our time indoors but relatively little is known about the air we breathe at these times.

Just before Covid restrictions were introduced in 2020, Dr Felix Leach of the University of Oxford took delivery of 16 air pollution monitors. With his project suddenly on hold, he set about testing the instruments in his own home and garden.

He quickly found that the greatest air pollution in his home aligned with cooking. He also discovered that the home laser-printer was another source.

Nitrogen dioxide, a pollutant normally associated with diesel exhausts, was on average three to 12 times higher indoors than outside. It was greatest in the kitchen from using the gas cooker and hob. This pollution persisted for hours, and often overnight until the outside door was opened in the morning.

Leach, who normally studies propulsion systems and air pollution, said: “The pollution in my home is way higher than the bit I have been worrying about professionally. Energy efficiency and ventilation are in tension, at least in my house, and I still haven’t got it right. As soon as my finances allow, I will be replacing my gas hob with an induction one.”

Leach is not alone in having these problems. Each year about 40,000 people in the UK and Europe are thought to die early from the long-term effects of nitrogen dioxide from gas cooking at home. It is also harming the health of those with chronic obstructive pulmonary disease.

Data is now emerging from the Ingenious project, which is working with families living in 310 homes in Bradford.

Prof Nic Carslaw, from the University of York, who leads the Ingenious project, said: “Air pollutants are emitted as you cook including a wide variety of compounds that lead to the aromas we associate with our favourite meals. The highest emissions of particles are produced by frying meat at a high temperature.”

Cover photo:  Average particle pollution in kitchens using gas was nearly twice that of electric, one study found. Photograph: Danny Lawson/PA