While many big Indian cities saw higher PM 2.5 levels in October, 2023, compared to the same period last year, Bengaluru saw a fall in PM 2.5 levels in October 2023 compared to the same period last year, according to an analysis by Respirer Reports.
It has found that while four cities -- Delhi, Mumbai, Hyderabad and Kolkata -- saw PM 2.5 levels higher in October, 2023, compared to a year ago, four State capitals saw a fall in October PM 2.5 levels between 2022 and 2023. They are Lucknow, Patna, Bengaluru, and Chennai. Respirer is a leading climate tech start up.
Eight state capitals
The study also analysed PM 2.5 concentrations between 2019 and 2023 in eight of India’s major State capitals which face air pollution challenges. These are Delhi, Mumbai, Chennai, Kolkata, Bengaluru, Lucknow and Patna.
“While some cities witnessed rising pollution levels, others, like Lucknow, Patna, Bengaluru, and Chennai, managed to reduce PM 2.5 levels, demonstrating the potential for successful air quality improvement efforts,” States the study.
The study found that in Bengaluru, PM 2.5 increased significantly between 2019 and 2020 (by 72.1%), fell slightly in 2021 (by 5.8%), went up again in 2022 (by 29.6%), and dipped once again in 2023 (by 11.6%).
The report found that Chennai was the least polluted, with a fall of over 23% compared to a year ago. Chennai’s PM 2.5 increased between 2019 and 2020 (by 43.2%), fell in 2021 (by 27.8%), rose again in 2022 (by 61.6%), and decreased in 2023 (by 23.7%).
Constant rise in Delhi
Delhi, the report states, has been experiencing a persistent upward trend in air pollution since 2021. “Delhi’s PM 2.5 level in October, 2023, was higher than a year ago, continuing a rising trend since 2021. It was the most polluted of the eight cities analysed here,” it added.