New Delhi: About 41 cities, mostly in north and central India, experienced “poor” to “severe” air quality on November 8, 2018, a day after Diwali, according to government data.

Seven cities, including Noida, Faridabad, Patna and Lucknow, recorded worse air than Delhi, according to the Air Quality Index (AQI) bulletin, which records a 24-hour average and is released every day at 4 pm by the Central Pollution Control Board (CPCB). AQI is a number used by governments to communicate to the public how polluted the air is. AQI of 100 is considered acceptable in India.

The plunging air quality after Diwali also took on religious overtones, with some arguing that a Hindu festival was being unfairly criticised and smoke from firecrackers is not the reason for Delhi's increased air pollution, and there is no evidence that the smoke had any long-term effects.

"This is absolute nonsense and away from reality," Arvind Kumar, chairman of the Centre for Chest Surgery at New Delhi's Sir Ganga Ram Hospital, told IndiaSpend. "There are ample data and literature to prove that every time there is a spike in PM 2.5 it leads to increased respiratory and cardiac mortality."

"The air in Delhi is unfit for human living," said Kumar. "OPDs (out patient departments) are flooded with people with breathing problems and irritation in their throats. The number of casualties coming in because of heart failures has increased. It is not only the lung that is damaged by polluted air. There is ample literature available to confirm all of this, and if anybody is saying otherwise, they don't understand the subject and are driven by commercial, political or religious interests. These interests have blinded them."

Indeed, studies suggest that exposure to even brief spikes in pollution could increase mortality.

Short-term exposure to air pollution was seen to cause premature deaths among the elderly, IndiaSpend reported on January 19, 2018. For each 10 µg/m3 daily increase in PM 2.5, the daily mortality rate increased by 1.05%, according to this December 2017 study by the Harvard T H Chan School of Public Health at Harvard University.

Delhi, currently regarded the world’s most polluted city, recorded “very poor” air with an AQI of 390, as per the CPCB bulletin.

Wazirpur in central Delhi was the most polluted area in the city with particulate matter (PM) 2.5 readings crossing 4,000 µg/m3 at 2.05 AM on November 8--66 times the national safe air standard of 60 µg/m3. PM 2.5 are air-borne particles 30 times finer than a human hair and can sicken or kill people by entering human lungs.

Firecrackers worsen already toxic air

Firecrackers on Diwali evening added to already deteriorating pollution levels across Delhi. In many areas of India’s capital, monitors showed pollution levels peaking between 8-10 pm, during which time the Supreme Court allowed firecrackers.

About 5 million kg of firecrackers were estimated to have been burnt in Delhi this Diwali, despite a Supreme Court ban. The city has not seen a single day of safe air for more than a month, as per IndiaSpend’s analysis of air quality data of Delhi’s 37 automatic air quality monitoring stations between October 1-November 6, 2018.

In terms of 24-hour averages, about 41 cities in India recorded poor-to-severe level AQIs.

Faridabad recorded the worst air with the 24-hour average AQI reaching 455, followed by Noida with an AQI of 432. Lucknow, Patna and Ghaziabad recorded “severe” air with the AQI at 412, 427 and 422, respectively. An AQI of 100 is considered acceptable.

Source: Central Pollution Control Board

Source: Central Pollution Control Board

Northern cities will continue to have poor air quality

Most of the North Indian cities we mentioned are not likely to breathe safer air over three days to November 11, according to an-all India forecast of PM 2.5 levels by Urban Emissions, a non-profit research group. The air will clear up only after November 10, 2018, according to the forecast.

Update: This story has been updated to incorporate the view of Arvind Kumar, Chairman of the Centre for Chest Surgery at New Delhi's Sir Ganga Ram Hospital.

(Tripathi is a principal correspondent with IndiaSpend.)

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