The small town of Byrnihat is the most polluted city in India with an AQI of 128.2µg/m³ with Delhi coming in close second with an AQI of 108.3µg/m³. Byrnihat in Meghalaya is a small town with a population of 5,444, according to the 2011 Census, and is an industrial area.
Six of the 10 most polluted cities in the world are in India for the year 2024. The quality of air continued to deteriorate in Delhi and Bengaluru. While Hyderabad, Kolkata, Mumbai had better air quality than that in 2023, Chennai’s air quality remained constant with an AQI of 28(μg/m³). The data about air quality was released by IQAir, a Swiss-based air quality technology company on Tuesday.
Even with improved air quality, Hyderabad, Kolkata, Mumbai and Chennai, remain in the red zone by exceeding World Health Organisation (WHO) PM2.5 guideline by five to seven times.
The report notes the challenges faced by the nation: “India saw a 7% decline in PM2.5 concentration in 2024, averaging 50.6 µg/m³ compared to 54.4 µg/m³ in 2023. Yet, six of the world’s 10 most polluted cities are in India. The capital, New Delhi, maintained consistently high pollution levels, with an annual average of 91.6 µg/m³, nearly unchanged from 92.7 µg/m³ in 2023.”
However, India has improved air quality over the last one year with the ranking of fifth most polluted country in the world, down from third the previous year.
“However, the World Air Quality Report had a pat for the country noting the investment in infrastructure to monitor and share air quality data. India continues to lead the region in government monitoring infrastructure, operating more than half of the total stations. Despite this, many areas in India remain under-monitored, particularly in smaller cities and rural regions,” says the report noting that more than half of the monitoring stations in Central and South Asia are in India.
Published – March 11, 2025 08:00 pm IST