One in three people worldwide are breathing in household air pollution, researchers warn

Household air pollution still kills millions of people every year, even as exposure levels fall worldwide, a new study has found.

In 2021, household air pollution – which occurs when people cook with open fires or stoves fuelled by kerosene, coal, wood, crop waste, or animal dung – contributed to 3.1 million deaths worldwide, with most deaths in lower-income countries, according to the analysis published in The Lancet medical journal.

Household air pollution contains small particles that can get into the bloodstream through the lungs.

It is linked to a slew of health issues, including lung cancer, stroke, heart disease, type 2 diabetes, chronic obstructive pulmonary disorder (COPD), respiratory infections, cataracts, and neonatal disorders.

It can also have deadly consequences for children, contributing to more than 500,000 deaths among children under the age of 5 in 2021, according to the study. That is about 11 per cent of all under-5 mortality.

“The high level of paediatric burden estimated in this study is a major cause for concern,” said the study authors from the US-based Institute for Health Metrics and Evaluation (IHME).

They added that the health effects can be “fatal and long lasting and have not received adequate attention from researchers and policy makers”.

Regional differences

Between 1990 and 2021, the percentage of people exposed to household air pollution from solid cooking fuels worldwide plummeted from 56.7 per cent to 33.8 per cent, the estimates show.

But the actual number of people exposed only fell by 10 per cent – or about 350 million people – reaching 2.67 billion people exposed in 2021.

That’s due to population growth in places like sub-Saharan Africa, where 78.8 per cent of people were exposed to household air pollution from solid cooking fuels, the study authors said.

Between 1990 and 2021, the number of pollution-related deaths rose from 685,000 to 741,000 in the region, IHME said.

South Asia had the next highest rate, with 53.2 per cent of people exposed in 2021.

Meanwhile, in central and eastern Europe and in central Asia, that rate was 7.5 per cent. In high-income countries, it was just 0.4 per cent.

The researchers said the results underscore the importance of helping “under-resourced communities” transition to cleaner energy sources. That could include research and development for new technologies, subsidising appliances that use clean energy, enforcing emissions restrictions, incentivising private sector investment, and public awareness campaigns.

“Such initiatives are crucial for mitigating health risks and promoting sustainable development, ultimately improving the quality of life and health outcomes for millions of people,” the study authors said.