Bangladesh has been ranked as the second most polluted country in the world for 2024, following Chad, with smog levels soaring more than 15 times higher than the World Health Organization’s (WHO) recommended safety threshold. The findings were released in a report by Swiss company IQAir on Tuesday.
Chad topped the global pollution rankings, with air pollution levels reaching 18 times the WHO’s safe limit for fine particulate matter (PM2.5), particles smaller than 2.5 microns in diameter. The WHO sets a safe level for PM2.5 at no more than 5 micrograms per cubic meter, a standard that was met by only 17% of cities globally in 2024.
IQAir’s report also highlighted the increasing impact of climate change on global air quality. Chester-Schroeder, IQAir’s Air Quality Science Manager, warned that climate change is contributing to the worsening pollution levels.
Pakistan ranked third in the pollution index, followed by the Democratic Republic of Congo and India. India remained a major contributor to global air pollution, with its capital, New Delhi, listed as the world’s most polluted capital. Bangladesh’s capital, Dhaka, came third in the global ranking of the most polluted capitals, after N’Djamena in Chad.
Despite some improvements, India continued to dominate the rankings for the most polluted cities. The industrial town of Byrnihat in India was the world’s most polluted metropolitan area of 2024, with PM2.5 concentrations averaging 128.2 micrograms per cubic meter—more than 25 times the WHO’s recommended limit. Overall, air quality across India showed an average PM2.5 level of 50.6 micrograms per cubic meter, ten times higher than the safe standard.
South Asia’s air quality deteriorates significantly in the winter months, with cities in India, Pakistan, and Bangladesh seeing alarmingly high pollution levels. In January, Baddi in Himachal Pradesh recorded PM2.5 levels of 165 micrograms per cubic meter—33 times the safe limit.
The IQAir report, based on data from over 40,000 air quality monitoring stations in nearly 9,000 locations across 138 countries, also revealed that Oceania was the cleanest region globally, with 57% of its cities meeting WHO standards. In contrast, Bosnia was the most polluted country in Europe, followed by North Macedonia and Serbia, where Novi Pazar was the most polluted city.
Only seven countries—Estonia, Iceland, Australia, New Zealand, the Bahamas, Grenada, and Barbados—had air pollution levels that fell below the WHO guidelines. The report noted a slight improvement in 2024, with 17% of cities worldwide meeting WHO’s air quality standard, up from 9% in 2023.
Air pollution remains a significant global health risk, responsible for an estimated 8.1 million premature deaths in 2021, according to the “State of Global Air 2024” report by the Health Effects Institute.
