Top 10 most polluted cities (with AQI) in the world 2025: Air pollution has become one of the most pressing environmental and public health concerns in recent years. The latest data from IQAir has revealed alarming air quality levels across several major cities worldwide, particularly in the Middle East and South Asia. According to IQAir data released on October 10, Baghdad, Iraq, currently ranks as the most polluted city in the world, with an AQI exceeding 170. Kolkata follows closely at the second spot, with PM2.5 concentrations pushing its AQI beyond 160—classified as “unhealthy.” Lahore, Pakistan, ranks fourth with an AQI of 160, while another Pakistani city, Karachi, records 157. In India, Delhi’s air quality has sharply deteriorated just ten days before Diwali, reaching an “unhealthy” AQI of 157 on the same day, according to IQAir. Experts attribute this rise to seasonal factors such as stubble burning in neighbouring states, combined with vehicular and industrial emissions. Other densely populated cities like Dhaka continue to face similar challenges, grappling with the combined effects of rapid urbanisation, traffic congestion, and poor emission control. Meanwhile, cities such as Detroit in the United States, Stockholm in Sweden, and Helsinki in Finland have maintained AQI levels below 20, making them some of the cleanest and least polluted urban areas in the world as of October 10. Top 10 most polluted cities in the world 2025: Rank City Country/Region AQI⁺ US 1 Baghdad Iraq 183 2 Kolkata India 170 3 Dhaka Bangladesh 162 4 Lahore Pakistan 160 5 Manama Bahrain 158 6 Kampala Uganda 158 7 Doha Qatar 157 8 Karachi Pakistan 157 9 Delhi India 155 10 Mumbai India 152 Note: Live AQI has been recorded as of October 10, 2025 (Friday) - 11:21 IST AM - on IQAir Air Quality Rankings. Stay updated with the latest – Click here to read more Top 10 exclusive reports!
