The air quality in Chennai, Tamil Nadu, deteriorated sharply this week, with the Air Quality Index (AQI) downgrading air quality in the city from "satisfactory" on Tuesday to "poor" on Wednesday and "very poor" on Thursday.
According to reports, the rapid deterioration of the air quality started around 7pm and online indicators of the pollution monitoring stations showed Delhi suffering "very poor" air quality on Diwali night.
Of course, in certain parts of Delhi, the levels were much higher, with PM2.5 and PM10 crossing 800 and 1,000 micrograms per cubic metre around the same time in RK Puram.
On Thursday evening, UoH recorded a PM 2.5 level of 105, while Zoo Park recorded a PM 2.5 level of 98.10, against the prescribed level of 60 microgram per metre cube.
"Mumbai also saw increased pollution levels as SAFAR data found the AQI to be 204 ('poor" category) due to emissions from firecrackers and changing weather patterns, according to Hindustan Times.
In Mumbai, areas like Colaba and Bhandup had better air quality even at the end of the day compared to areas of western suburbs like Andheri and Borivali which had AQI of 253 and 229 respectively.
The AQI this year even at "very poor", is an improvement from last year's "severe", noted Business Today.
Meanwhile, across south Indian cities, as well as in Kolkata, the pollution was declining by October 20. "Last year, we had recorded 113 decibels but this time we have recorded readings of 104 decibels so far".
As per an official of central government agency SAFAR, which monitors air pollution, burning of paddy stubble in Haryana and Punjab, meteorological conditions and recent fire breakouts at Ghazipur landfills are some of the major reasons behind the alarming level of air pollution in the national capital.
The New Indian Express reported that a thick blanket of smog had entered homes as pollution levels hit an all-time high posing serious health hazards.
An AQI reading of "very poor" essentially means that people may suffer from respiratory illnesses on a prolonged exposure to such air. United States consulate, which records PM2.5 count across the globe, found sudden spike in pollution after a long period of satisfactory ambient air quality. It was Delhi's worst Diwali in three years in terms of air quality as a deadly cocktail of harmful pollutants and gases engulfed the city in thick smog. Initially, Diwali got off to a much quieter start with much lesser noise and smoke till about 6 pm, compared to the previous years.
As many as 2.51 million people in the country have died prematurely that year due to diseases linked to air, water and other forms of pollution.