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Main image: Heating molten bronze for the manufacturing of ship propellers in Bangladesh, the most polluted country in 2023
The sixth Annual World Air Quality Report reveals troubling details of the world’s most polluted countries, territories and regions in 2023.
For this year’s report, data from more than 30,000 air quality monitoring stations across 7,812 locations in 134 countries, territories and regions were analysed by IQAir’s air quality scientists.
Seven countries met the WHO annual PM2.5 guideline (annual average of 5 μg/m3 or less): Australia, Estonia, Finland, Grenada, Iceland, Mauritius and New Zealand.
According to the World Air Quality Report, the top five most polluted countries in 2023 were:
A total of 124 (92.5%) out of 134 countries and regions exceeded the WHO annual PM2.5 guideline value of 5 μg/m3.
Africa remains the most underrepresented continent, with a third of the population still lacking access to air quality data.
Climate conditions and transboundary haze were major factors in Southeast Asia, where PM2.5 concentrations rose in nearly every country.
The region of Central & South Asia was home to the top 10 most polluted cities in the world.
Begusarai, India was the most polluted metropolitan area of 2023. India was home to the four most polluted cities in the world.
The most polluted major US city was Columbus, Ohio. Beloit, Wisconsin was the most polluted city in the US.
Las Vegas, Nevada was the cleanest major city in the US.
For the first time in the history of this report, Canada was the most polluted country in Northern America, with the region’s 13 most polluted cities located within its borders.
70% of the real-time air quality data in the region of Latin America & Caribbean comes from low-cost sensors.
While the number of countries and regions with air quality monitoring has steadily increased over the past six years, there remain significant gaps in government-operated regulatory instrumentation in many parts of the world.
Low-cost air quality monitors, sponsored and hosted by citizen scientists, researchers, community advocates and local organisations, have proven to be valuable tools to reduce gaps in air monitoring networks across the world.
‘A clean, healthy, and sustainable environment is a universal human right. In many parts of the world the lack of air quality data delays decisive action and perpetuates unnecessary human suffering. Air quality data saves lives. Where air quality is reported, action is taken, and air quality improves.’
FRANK HAMMES
Global CEO, IQAir
These independent air quality monitoring stations reveal disproportionate exposure to harmful air pollution among vulnerable and underrepresented groups.
Glaring gaps in air quality monitoring data, where pollution is likely poor, further underline the need to expand air quality monitoring coverage worldwide.
‘IQAir’s annual report illustrates the international nature and inequitable consequences of the enduring air pollution crisis. Local, national and international effort is urgently needed to monitor air quality in under-resourced places, manage the causes of transboundary haze, and cut our reliance on combustion as an energy source.
‘In 2023 air pollution remained a global health catastrophe, IQAir’s global data set provides an important reminder of the resulting injustices and the need to implement the many solutions that exist to this problem.’
AIDAN FARROW
Sr Air Quality Scientist, Greenpeace International
States must safeguard children’s rights from climate change and environmental damage.
More than a third of fertiliser use is breaking government emissions thresholds.
New data reveal the social impact of air pollution – with 48% of young people considering leaving cities in search of cleaner air.
New report reveals only 5% of countries meet WHO PM2.5 pollution guideline.
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