Cooking smoke kills millions every year. Here’s what the world can do about that.

For billions of people across the developing world, particularly children and women, mealtime starts by firing up a kerosene stove, lighting a charcoal grill or setting some logs ablaze.   The problem: much of this cooking happens inside and the smoke it produces is laced with toxic particles. This type of household air pollution led to 3.1 million premature deaths in 2021 and is part of a larger crisis driving climate change and biodiversity loss.   “Household air pollution is one of the world’s greatest public health threats and it is particularly harmful for children,” says Martina Otto, Head of Secretariat of the Climate and Clean Air Coalition of the United Nations Environment Programme (UNEP).  “But the good news is that cleaner cooking technology is plentiful, relatively inexpensive, and already helping to save lives. The challenge now is to get this technology into the hands of more people.”  Yet, household air pollution is still the most underinvested health and environmental problem in the world.   On 7 September, International Day of Clean Air for blue skies takes place, which is designed to raise awareness about the dangers of air pollution. Ahead of the Day, here’s a closer look at the causes of household air pollution, and how cleaner cooking methods can save lives, counter climate change and slow biodiversity loss. How widespread is household air pollution?  Worldwide, nearly one in three people cook on inefficient stoves or over open fires, breathing in harmful smoke from so-called solid fuels such as wood, charcoal and animal dung. The problem is especially acute in Africa, where nearly four in five people are exposed to household air pollution. That is part of a larger air pollution crisis. Some 99 per cent of the world breathes household or outdoor air that the World Health Organization considers unsafe.   What exactly is household air pollution? There are many types of indoor air pollutants, including mould, asbestos and carbon monoxide. But when experts refer to household air pollution, they’re talking specifically about the contaminants that arise from inefficient stoves and open fires. Among the most damaging of these are microscopic specs of dirt, dust, smoke, soot and black carbon known as fine particulate matter.   What does household air pollution do to the human body?  Fine particulate matter less than 10 microns in size – which is less than the width of a human hair – can enter the lungs and bloodstream. From there, it can cause serious health problems, including pneumonia, heart disease, stroke and lung cancer, low birthweight and stillbirths.   Who suffers the most from household air pollution?   Household air pollution is devastating for everyone. It led to the premature deaths of an estimated 3.1 million people in 2021. Children are especially vulnerable because they breathe at a faster rate than adults – meaning they inhale more pollutants – and their immune systems are still developing, leaving them less able to fight off disease. In 2021, household air pollution led to the deaths of 237,000 children under five. Household air pollution also disproportionately affects women, as they are most often doing the cooking. In Africa, women and children account for 60 per cent of early deaths related to smoke inhalation and household air pollution, according to the International Energy Agency.  What is clean cooking?  The most common definition of clean cooking is any fuel and stove combination that meets World Health Organization’s guidelines for indoor air quality. That usually includes stoves powered by electricity, biogas, ethanol and liquid petroleum gas, which are cleaner and more efficient than their solid fuel cousins. It can also include stoves that use high-efficiency charcoal and biomass pellets; these devices produce less smoke than traditional biomass stoves. Related Story Seven things you should know about household air pollution