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25. Tianjin, China -

At number 25 in the rankings is the northern Chinese city of Tianjin. Here the average PM2.5 is 44.9 µg/m3. That's 1.2 times above the recommended limit.

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24. Baghdad, Iraq -

Baghdad, the capital city of Iraq, also has a PM2.5 of 44.9 µg/m3.

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23. Taiyuan, China -

Taiyuan, the capital and largest city of China's Shanxi province, has a PM2.5 of 45.2 µg/m3.

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22. Chandigarh, India -

The PM2.5 of the northern Indian city of Chandigarh is 45.8 µg/m3.

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21. Visakhapatnam, India -

Despite being located on the coast, Visakhapatnam, the largest and most populous city in the Indian state of Andhra Pradesh, has a PM2.5 of 46.8 µg/m3.

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20. Dubai, United Arab Emirates -

The PM2.5 in Dubai is 47.8 µg/m3. The most populous city in the UAE is also currently the most polluted of the country's seven emirates.

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19. Kathmandu, Nepal -

Its location in a low valley on a high plateau means Kathmandu, the capital city of Nepal, tends to trap polluted air, edging the PM2.5 up to 48.5 µg/m3.

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18. Shijiazhuang, China -

Shijiazhuang, the capital and most populous city of China's Hebei province, has a PM2.5 of 48.6 µg/m3.

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17. Lanzhou, China -

Located on the banks of the Yellow River in northwestern China, Lanzhou, the capital and largest city of Gansu province, currently records an PM2.5 of 49.5 µg/m3.

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16. Xinxiang, China -

A city undergoing exponential growth, Xinxiang's PM2.5 is 51.6 µg/m3. It's located in China's northern Henan province.

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15. Lucknow, India -

The capital and the largest city of the Indian state of Uttar Pradesh, Lucknow has a PM2.5 of 53.1 µg/m3.

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14. Zhengzhou, China -

A major hub of China's domestic and international transportation network, Zhengzhou, in Henan province, has a PM2.5 of 53.3 µg/m3.

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13. Ghaziabad, India -

Ghaziabad is the largest city in western Uttar Pradesh. Its PM2.5 is 53.5 µg/m3.

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12. Dushanbe, Tajikistan -

Tajikistan's capital Dushanbe has a PM2.5 of 53.8 µg/m3. The city is a hotspot of polluting industries such as coal power plants and waste-burning sites. The pollution serves as a blanket over the valley in which Dushanbe is situated, trapping tainted air.

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11. Anyang, China -

Another city in China's Henan province blighted by air pollution, Anyang has a PM2.5 of 54.6 µg/m3.

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10. Peshawar, Pakistan -

The capital of the province of Khyber Pakhtunkhwa, where it is the largest city, Peshawar's PM2.5 is 56.2 µg/m3.

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9. Xuchang, China -

And China's Henan province is again cited by the AQI as a region with high air pollution levels, with Xuchang recording a PM2.5 of 57.0 µg/m3.

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8. Xi’an, China -

Xi'an, the capital of Shaanxi province, has an unhealthy PM2.5 of 57.9 µg/m3.

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7. Muzaffarnagar, India -

The industrial city of Muzaffarnagar in Uttar Pradesh edges the PM2.5 to a worrying 62.4 µg/m3.

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6. Urumqi, China -

Urumqi in China's far northwest has an average PM2.5 of 63.4 µg/m3. As well as being the largest city in Central Asia in terms of population (approximately four million), Urumqi is the most remote city from any sea in the world, according to Guinness World Records.

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5. New Delhi, India -

The capital city of India faces a concerning PM2.5 concentration of 64.0 µg/m3. Recently, New Delhi's 24-hour AQI reached 491, classified as "severe plus," marking the highest level of pollution recorded this season, according to India's pollution control authority.

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4. New Delhi, India -

AQI levels at several stations across Delhi surpassed 500, with others hovering between 490 and 500. Around 35 million people live in the city, a place known for its high levels of harmful air pollution.

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3. Patna, India -

The third most polluted city in 2024 is Patna, the capital and largest city of the Indian state of Bihar. Patna's PM2.5 is 67.0 µg/m3.

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2. Lahore, Pakistan -

Lahore, the second largest city in Pakistan, after Karachi, is also the world's second most polluted city, averaging a PM2.5 of 95.1 µg/m3.

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1. Dhaka, Bangladesh -

And the world's most polluted city  according to the Air Quality Index project is Dhaka, the capital and largest city of Bangladesh. The PM2.5 here averages a noxious 114.5 µg/m3, which is perhaps not surprising as Dhaka is widely considered to be the most densely populated built-up urban area in the world.

Sources: (WHO) (AQI) (United Nations Environment Programme) (IQAir) (Statista) (Guinness World Records)  

See also: How air pollution is interfering with bee pollination

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