New Delhi: Delhi had the highest PM (Particulate Matter) 2.5 levels in the country in the month of October and has been experiencing a consistent upward trend since 2021, according to the Respirer Report. The report, on analysis of air quality over the past five years, said that while air pollution has increased in the country's four major cities, it has fallen in state capitals like Lucknow and Patna, according to a recent report.
It indicates that while Delhi, Mumbai, Hyderabad and Kolkata saw PM 2.5 levels higher in October 2023, compared to a year ago, Chennai saw a fall of over 23 per cent compared to a year ago.
The study analysed PM 2.5 concentrations between 2019 and 2023 in eight of India's major state capitals-- Delhi, Mumbai, Chennai, Kolkata, Bengaluru, Lucknow and Patna.
Lucknow and Patna
In Lucknow and Patna, October PM 2.5 levels dropped between 2022 and 2023, holding on to gains from previous years.
In Lucknow, PM 2.5 spiked between 2019 and 2020 by 55.2 per cent, dipped in 2021 by 53.4 per cent, went up again in 2022 by 6.2 per cent and fell again in 2023 by 0.9 per cent.
"In Patna, PM 2.5 fell between 2019 and 2020 by 14 per cent, dipped further in 2021 by 36.7 per cent, spiked significantly in 2022 by 47.7 per cent, then went down again in 2023 by 11.1 per cent," the report said.
Bengaluru and Chennai
In Bengaluru and Chennai, October PM 2.5 levels fell between 2022 and 2023.
In Bengaluru, PM 2.5 increased significantly between 2019 and 2020 by 72.1 per cent, fell slightly in 2021 by 5.8 per cent, went up again in 2022 by 29.6 per cent and dipped once again in 2023 by 11.6 per cent.
In Chennai, PM 2.5 increased between 2019 and 2020 by 43.2 per cent, fell in 2021 by 27.8 per cent, rose again in 2022 by 61.6 per cent and decreased in 2023 by 23.7 per cent.
Pollution in Mumbai
As per the report, Mumbai saw a steady increase in October PM 2.5 levels from 2019 to 2023, signalling a significant deterioration in air quality.
"In Mumbai, last month, pollution spiked by over 42 per cent compared to October a year ago. In earlier years, PM 2.5 shot up between 2019 and 2020 (by 54.2 per cent), fell slightly in 2021 (by 3 per cent) and 2022 (by 0.9 per cent)," the report said.
Hyderabad and Kolkata
In Hyderabad and Kolkata, October PM 2.5 levels went up in 2023 compared to 2022.
In Hyderabad, PM 2.5 increased between 2019 and 2020 by 59 per cent, dipped slightly in 2021 by 2.9 per cent and considerably in 2022 by 29.1 per cent, but went up again in 2023 by 18.6 per cent. In Kolkata, PM 2.5 dipped between 2019 and 2020 by 26.8 per cent, went up in 2021 by 51.7 per cent, decreased in 2022 by 33.1 per cent and rose again in 2023 by 40.2 per cent.
