CHENNAI: In one way, the lockdown has been a boon for Chennai as air pollution levels saw a sizable reduction with residents of the city breathing better than their counterparts in the other southern metros of Bengaluru and Hyderabad.
According to a study by Greenpeace India, using the Central Pollution Control Board data, in April this year, PM 2.5 reduced in the city by 55.56 percent and the concentration of NO2 (nitrogen dioxide) reduced by 23.86% in comparison to last year.
The city’s PM 2.5 levels were 17.79 μg/m3, while the NO2 levels were 8.52 μg/m3.
Chennai's pollution levels were much less than in Bengaluru, whose PM 2.5 levels were 24.72 μg/m3 and NO2 concentration were 12.00 μg/m3, and Hyderabad, whose PM 2.5 levels were 30.38 μg/m3 and NO2 levels were 12 μg/m3 during the same period.
Bengaluru had recorded a 51 percent reduction in PM 2.5 levels, marginally lower than Chennai, while NO2 reduced was 64.02 percent. Whereas, in Hyderabad, there was just an 18.35 percent decrease in PM 2.5 levels while NO2 levels were down by 63.99 percent.
Avinash Chanchal, Senior Campaigner at Greenpeace India, said that it is very important to address long-term air quality problems that require ambitious policies.
"We experienced a massive reduction in air pollution and breathed cleaner air during such a difficult time and it indicates that human activity is the source of air pollution and if we can take necessary steps, a future with better air quality is possible,’’ he told The New Indian Express.
Studies have also highlighted that higher exposure to PM 2.5 leads to an increase in the COVID-19 mortality rate.
According to a Harvard University study, COVID-19 death counts were collected for more than 3,000 counties in the United States (representing 98% of the population) up to April 22, 2020 from Johns Hopkins University, Center for Systems Science and Engineering Coronavirus Resource Center.
“An increase of only 1 μg/m3 in PM 2.5 is associated with an 8% increase in the COVID-19 death rate,’’ said the study.
Similarly, according to the ‘Toxic Air: The Price of Fossil Fuels’ report, NO2 is linked to roughly 350,000 new cases of asthma in children each year with approximately 1,285,000 children in India living with asthma due to exposure to it from fossil fuels.
“We need to ensure strict implementation and inclusion of all non-attainment cities like Chennai under the National Clean Air Program (NCAP), increase the use of public transport, cycling and walking and put an effective waste management system in place,’’ added Chanchal.