A new analysis shows that pollution levels remained above permissible limits in Lucknow and Delhi despite lockdown-induced dips. The study by a climate communications initiative Climate Trends says researchers compared the Central Pollution Control Board (CPCB) air quality data for Delhi, Lucknow, Mumbai and Kolkata over the three months of March, April and May in 2019 – when there was no lockdown and 2020 and 2021 – when there was complete lockdown in these cities.
Though Delhi’s average PM 2.5 concentration for the three months dipped from 95.6 ug/m3 in 2019 to 69 ug/m3 in 2020, it went up to 95 ug/m3 in 2021.
The study revealed that except Mumbai, all cities showed a dip in the average PM 2.5 levels during the three months in 2020. Mumbai, however, has seen a gradual increase in pollution over the years, the study revealed.
The safe upper limit for PM 2.5 (particulate matter measuring less than 2.5 microns) as prescribed by the CPCB is 40 micrograms per cubic metre (ug/m3).