Blog 19 June 2024
Air pollution remained a leading cause of death in 2021, resulting in 8.1 million deaths and millions of healthy years of life lost worldwide, according to the new State of Global Air 2024 report.
The State of Global Air is a research and outreach initiative providing reliable, meaningful information about air quality around the world. A collaboration between the Health Effects Institute, the Institute for Health Metrics and Evaluation’s Global Burden of Disease project and UNICEF, the initiative provides access to high-quality, objective information about air pollution and its health impacts for over 200 countries. All data and reports are free and available to the public.
There is good news: we are witnessing a reduction or stabilisation in levels of ambient particulate matter pollution (PM2.5) in many countries. However, air pollution remains the single largest environmental health risk factor with significant public health, societal and economic implications. Below, are three key findings from the 2024 report.
Children around the world continue to experience poor health due to exposure to air pollution
In 2021, air pollution was the second leading risk factor for death among children under 5, after malnutrition. Exposure to air pollution was linked to 700,000 deaths in children under 5, approximately 15% of all global deaths in children under 5. The silver lining is that the global burden of disease for children under 5 years attributable to air pollution has dropped steadily in the last few decades: since 2000, the death rate linked to air pollution decreased by more than 50%. It’s clear that addressing air pollution is an essential step achieving the UN Sustainable Development Goal of substantially reducing under-5 mortality.
Air pollution contributes significantly to the global noncommunicable disease burden
Nearly 90% of the deaths from air pollution in 2021 were due to noncommunicable diseases. When inhaled, air pollution can cause inflammation not only in the lungs, but also throughout the body, causing oxidative stress and damaging vital organs like the heart. These health impacts can lead to noncommunicable diseases (NCDs), such as stroke and heart disease, largely due to the stress caused by air pollution.
In areas where air pollution exposure is high, people breathe in more pollution, more regularly, increasing their risk of disease. In 2021, air pollution accounted for:
- 48% of global deaths from COPD
- 28% from ischemic heart disease
- 27% from stroke
- 19% from lung cancer
- 18% from type 2 diabetes
Many of these deaths were linked to exposure to particulate matter pollution (PM2.5), both outdoors and in households.
Significant regional differences underlie the global averages. High-income countries such as Finland, Norway, Australia and Canada see less than 10% of ischemic heart disease deaths attributed to air pollution. But attributed deaths increase to over 40% in parts of East, West, Central, and Southern Africa and South Asia, including Nigeria, Kenya and Bangladesh. Similarly, in countries including Kuwait, Nepal, Egypt, Pakistan, China, Rwanda and Tajikistan, 1 in 5 deaths due to Type 2 diabetes is linked to exposure to air pollution.
As the connection between air pollution and NCDs grows stronger, policymakers around the world are using NCDs as a lens to look at how air pollution impacts health across populations. By understanding the connection between air pollution and risk of diseases like stroke and cancer, air pollution can be integrated into public health planning and programmes. For example, the European Union has included reducing environmental pollution as an important part of its Beating Cancer Plan.
Levels of ozone are increasing
Ozone is an air pollutant and a greenhouse gas that exacerbates climate change. 93% of the world’s population lived in areas with peak seasonal ozone levels higher than the World Health Organization’s (WHO) guidelines for peak season ozone (60 µg/m3 or 31 ppb). Furthermore, the proportion of population experiencing high ozone exposures is increasing in many regions of the world.
In 2021, exposure to ambient ozone was linked to an estimated 489,000 deaths and 8.7 million healthy years of life lost worldwide. Since 2010, the total numbers of deaths attributed to ozone have increased by 20% with significant impacts in low- and middle-income countries. Countries with the highest average ozone exposures are in the Middle East (Qatar, Bahrain, Kuwait, Saudi Arabia, and Iraq), South Asia (Nepal, India, Bangladesh, and Pakistan), and East Asia (Republic of Korea).
As we write this, parts of the United States are under severe heat warnings. In the last two months, countries including India, Pakistan, Nigeria and the Philippines have experienced record-breaking heatwaves with temperatures reaching 50°C in some locations. Heat waves can worsen ozone pollution, threatening human health and crop yields. In fact, recent studies have reported spikes in ozone pollution during heatwave events in China and Europe. These data further highlight the need for integrated action on air pollution and climate change.
Data for trends in exposures as well as health impacts for countries is available via the State of Global Air data app.
