India, Pakistan, and Bangladesh experienced the poorest air quality in 2023, with Bangladesh surpassing the World Health Organization’s (WHO) safety guidelines by nearly 16 times on average, to claim the top spot on the list of the world’s most polluted countries.
Average concentrations of PM2.5, which are small airborne particles damaging to the lungs, reached 79.9 micrograms per cubic meter in Bangladesh and 73.7 micrograms in Pakistan in 2023, far exceeding the WHO recommendation of no more than 5 micrograms.
“Because of the climate conditions and the geography (in South Asia), you get this streak of PM2.5 concentrations that just skyrocket because the pollution has nowhere to go,” said Christi Chester Schroeder, air quality science manager at IQAir, a Swiss air monitoring organization.
“On top of that are factors such as agricultural practices, industry and population density,” she added. “Unfortunately, it really does look like it will get worse before it gets better.”
Bangladesh was ranked fifth and India was eighth on the list of countries with the worst air quality in 2020.
Md Firoz Khan, an air pollution expert at Dhaka’s North South University, said that about 20% of premature deaths in Bangladesh are attributed to air pollution, with related healthcare costs amounting to 4% to 5% of the country’s GDP.
Pollution levels in India also surged last year, with PM2.5 levels approximately 11 times higher than the WHO standard. New Delhi, India’s capital city, ranked as the worst-performing capital with PM2.5 levels at 92.7 micrograms.
“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,” states Frank Hammes, Global CEO, IQAir.
In 2023, China experienced a 6.3% increase in PM2.5 levels, rising to 32.5 micrograms, marking a reversal after five consecutive years of decline.
Top five most polluted countries in 2023 were
- Bangladesh (79.9 µg/m3) more than 15 times higher than the WHO PM2.5 annual guideline
- Pakistan (73.7 µg/m3) more than 14 times higher than the WHO PM2.5 annual guideline
- India (54.4 µg/m3) more than 10 times higher than the WHO PM2.5 annual guideline
- Tajikistan (49.0 µg/m3) more than 9 times higher than the WHO PM2.5 annual guideline
- Burkina Faso (46.6 µg/m3) more than 9 times higher than the WHO PM2.5 annual guideline
Out of 100 most polluted cities 83 are in India
Nine of the top 10 most polluted cities are in India, compared with six cities the previous year. Additionally, 42 cities out of the top 50 are in India, up from 39, and a remarkable 83 cities out of the top 100 are Indian, rising from 63 and 65 in 2022 and 2021.
Delhi has been ranked as the most polluted capital of the world for the fifth time in the last six years. Its PM2.5 level has averaged over 102 micrograms per cubic meter, an increase of 10 units from the previous year, far exceeding the WHO’s safe guideline of just 5 micrograms.
Pakistan ranked second most polluted country in 2023
Pakistan maintained the second worst air quality with an average PM2.5 concentration of 73.7 micrograms per cubic meter (μg/m³).
According to the report, PM2.5 levels in Islamabad reached their highest-ever recorded levels in the city’s seven-year history, at 42.4μg/m³.
Lahore, previously labeled the world’s most polluted city in March 2023, also experienced a significant increase in PM2.5 levels, exceeding 20μg/m³, with levels reaching 99.5µg/m³. The city’s monthly average PM2.5 level peaked at 251µg/m³ in November last year, prompting courts to direct the government to declare a “smog emergency” in the provincial capital.
“Every city in Pakistan included in the 2023 report measured concentrations above 30µg/m3, at least six times the recommended WHO annual PM2.5 guideline,” the report said.
Key findings from the 2023 World Air Quality Report
- The region of Central & South Asia was home to the top ten most polluted cities in the world.
- Australia, Estonia, Finland, Grenada, Iceland, Mauritius and New Zealand were the only countries that met WHO standards in 2023.
- The most polluted major U.S. city was Columbus, Ohio. Beloit, Wisconsin was the most polluted city in the U.S.
- Las Vegas, Nevada was the cleanest major city in the U.S.
- For the first time in the history of the IQAir report, Canada was the most polluted country in Northern America, with the region’s 13 most polluted cities located within its borders.
