The 2024 World Air Quality Report by IQAir reveals alarming levels of pollution in several countries, with Chad, Bangladesh, and Pakistan ranking among the most polluted in the world.
The report, based on data from over 40,000 air quality monitoring stations across 138 countries, territories, and regions, underscores the urgent need for action as air pollution continues to threaten public health and the environment on a global scale.
Key Findings from the 2024 Report
- 17% of Global Cities Meet WHO Air Quality Standards: Only a small fraction of the world’s cities—17%—comply with the World Health Organization’s (WHO) air pollution guidelines, which recommend that annual PM2.5 levels should not exceed 5 µg/m³.
- Byrnihat, India, is the Most Polluted City in the World: The industrial town of Byrnihat in India recorded a staggering annual PM2.5 concentration of 128.2 µg/m³, more than 25 times the WHO’s safe level.
- Oceania leads with the Cleanest Air: Oceania was the world’s cleanest region, with 57% of cities meeting WHO’s PM2.5 guidelines. Cities in countries like Australia, New Zealand, and Papua New Guinea contributed to the region’s better-than-average air quality.
- Los Angeles, California, was the most polluted city in the U.S., whereas Seattle, Washington, was the cleanest major city in the United States.
- Wildfires in the Amazon rainforest impacted vast areas of Latin America in 2024, with PM2.5 levels in some cities across Brazil’s Rondônia and Acre states quadrupling in September.
- Progress and Gaps in Monitoring: Over the past year, there has been progress in expanding air quality monitoring, with the introduction of low-cost air quality monitors by citizen scientists, researchers, and local organizations. However, significant data gaps remain, especially in regions like Africa, where one monitoring station serves an average of 3.7 million people.
World’s Most Polluted Countries
in 2024, Chad reclaimed the position of having the world’s highest annual average pm2.5 concentration. Chad was followed by Bangladesh, Pakistan, the Democratic Republic of the Congo, and India as the top five most polluted countries in 2024.
The five most polluted countries in 2024 were:
- Chad: 91.8 µg/m³ (more than 18 times higher than WHO’s guideline)
- Bangladesh: 78.0 µg/m³
- Pakistan: 73.7 µg/m³
- Democratic Republic of the Congo: 58.2 µg/m³
- India: 50.6 µg/m³
Which countries have the best air quality?
Australia, the Bahamas, Barbados, Estonia, Grenada, Iceland, and New Zealand all met the WHO air quality guidelines. The cleanest city globally was Mayaguez, Puerto Rico, with an annual PM2.5 concentration of just 1.1 µg/m³.
Oceania, including Australia, New Zealand, and smaller Pacific islands, had the cleanest air, with 57% of cities meeting WHO standards. Overall, 17% of cities globally met the guidelines, a notable increase from just 9% in 2023.
Health Risks of Air Pollution
Air pollution continues to be one of the greatest global threats to public health. According to the WHO, exposure to PM2.5 particles, which are less than one-twentieth the width of a human hair, can penetrate the lungs and enter the bloodstream, causing severe respiratory issues, strokes, heart disease, and even cancer.
Air pollution is the second leading global risk factor for death, and the second leading risk factor for deaths among children under five,
following malnutrition. In 2021 alone, air pollution was responsible for 8.1 million deaths globally, and exposure to fine particulate matter contributed to over half of those fatalities.
IQAir CEO Frank Hammes emphasized the gravity of the situation: “Air pollution remains a critical threat to both human health and environmental stability, yet vast populations remain unaware of their exposure levels.” He added: Air quality data saves lives. It creates much needed awareness, informs policy decisions, guiding public health interventions, and empowers communities to take action to reduce air pollution and protect future generations.”
Role of Schools in addressing the crisis
The report highlights the disproportionate impact of air pollution on children, who face long-term health consequences from exposure to polluted air. Aidan Farrow, Senior Air Quality Scientist at Greenpeace International, remarked, “By highlighting the disproportionate risk posed to young people by air pollution, the report reminds us that a failure to act today will be felt by future generations.”
IQAir’s new Schools4Earth initiative aims to leverage the role of educational institutions in tackling the global air quality crisis. By providing over 1 million schools with low-cost air quality monitors, IQAir hopes to expand access to real-time, hyper-local pollution data. Currently, only 21% of the world’s population has access to such data. This initiative could provide air quality monitoring to over 94% of the global population, potentially saving millions of lives.
“Schools are at the center of communities, making them ideal locations for air quality monitoring,” said Hammes. “By outfitting schools worldwide with air quality monitors, we can create a global movement for cleaner air.”
Call for Collective Action
The 2024 report calls for urgent international efforts to reduce pollutant emissions, with a particular focus on activities like coal burning and deforestation, which significantly contribute to air pollution. With global air pollution levels continuing to rise, the report urges policymakers to take decisive actions to protect public health and the environment.
“The World Air Quality Report should be a rallying call for urgent and concerted international efforts to cut pollutant emissions. Air quality, climate change, and the world that will be inherited by our children are inextricably linked,” Aidan Farrow concluded.
While the data presented in the 2024 World Air Quality Report is sobering, it also presents a critical opportunity for countries, organizations, and individuals to take action. Expanding air quality monitoring, enforcing stricter emissions regulations, and increasing public awareness about the health impacts of pollution are essential steps in combating the global air quality crisis
What can governments do?
Reduce Emissions
- Integrate WHO air quality guidelines into future standards.
- Commit to decarbonization and expand renewable energy use.
- Promote clean energy in public transport systems and clean vehicles.
- Strengthen vehicle and industrial emission limits.
- Prohibit agricultural and biomass burning.
Support Sustainable Infrastructure
- Invest in pedestrian-friendly infrastructure and green spaces.
- Offer financial incentives for clean transport and renewable energy projects.
- Foster responsible forest management to prevent wildfires.
Expand Monitoring Framework
- Increase government-operated air quality stations.
- Support community-driven monitoring efforts through financial incentives.
What can citizens do?
Advocate for Air Quality
- Support local and national air quality initiatives.
- Back policymakers prioritizing clean air.
Limit Exposure
- Use apps like IQAir for real-time updates.
- Reduce outdoor activities on high pollution days.
- Wear masks during unhealthy air quality periods.
Reduce Personal Footprint
- Walk, bike, or use public transport.
- Cut energy consumption and recycle.
- Opt for eco-friendly heating and cooking methods.
Key Takeaways
- 17% of global cities meet WHO air quality standards.
- The five most polluted countries in 2024 are Chad, Bangladesh, Pakistan, the Democratic Republic of the Congo, and India.
- Byrnihat, India, recorded the highest levels of pollution, with PM2.5 concentrations 25 times above WHO standards.
- Oceania has the cleanest air, with 57% of cities meeting WHO guidelines.
- Over 90% of countries exceed WHO’s PM2.5 guidelines, with notable gaps in monitoring in regions like Africa.
- IQAir’s Schools4Earth initiative aims to expand air quality monitoring in schools worldwide to improve public health responses.