When indoor air pollution makes the news in Western countries, it often feels like a local concern. One week, the focus is on wood-burning stoves. Another, it is gas cookers or whether people should open their windows more often during winter.
In developing countries, indoor air pollution is usually framed as a development problem, linked to people cooking and heating with wood, charcoal or other solid fuels, often in homes with limited ventilation.
These two debates rarely intersect. Our new study, which analyses air-pollution-related mortality risk across 150 countries, suggests they are in fact describing the same public health challenge.
We find that air pollution, including exposure inside homes, contributes substantially to premature death worldwide – deaths that occur earlier than expected because air pollution increases the risk of disease. While exposure levels and pollution sources vary widely, indoor air pollution consistently adds to national mortality risk across all income levels.
When indoor air pollutants are inhaled, they can trigger inflammation and place long-term strain on the heart and respiratory system. The same biological processes occur whether pollution comes from a wood stove in a rural village or from a poorly ventilated cooker in a modern urban flat.
Our study does not measure household-level behaviour or individual exposure. Instead, we take a broader perspective, analysing country-level patterns and examining how access to clean cooking fuels, electricity, healthcare and wider socioeconomic conditions relate to air-pollution mortality risk.
The results show a clear and consistent pattern. Countries such as the UK, with widespread access to clean household energy and strong health systems, experience much lower mortality risk linked to air pollution. By contrast, countries including Benin, Cameroon, Guinea, Sierra Leone and Togo – where energy deprivation remains widespread – face far higher risks.
Most existing research on indoor air pollution focuses on rural households and communities. This work is essential, but it often misses the larger structural picture. Our research reveals the global pattern and shows that the same broad drivers influence risk across regions and income groups.
At a macro level, access to clean fuels and reliable electricity lowers air-pollution mortality risk, while higher healthcare spending further reduces it. Larger rural populations and limited access to household energy increase risk.
These patterns help explain why air-pollution deaths remain concentrated in emerging and developing economies, while advanced economies experience far fewer deaths, even though air pollution has not disappeared. They also show that indoor and outdoor air pollution cannot be treated as separate issues, because both reflect how energy is produced, used and regulated.
Reducing indoor air pollution often requires modest changes, such as using extractor fans, ventilating homes regularly and maintaining heating appliances. In developing countries, however, meaningful reductions depend on access to clean cooking fuels, rural electrification and stronger healthcare systems.
Overall, our findings underline the central role of clean household energy and robust health systems in reducing deaths linked to air pollution. Indoor air pollution is best understood not as two separate problems, but as one shared global health challenge with common causes and consequences.
The Conversation