People buy posters of Hindu god and goddess ahead of Diwali festival at a market in Amritsar on November 10, 2020. Photo: AFP/Narindar Nanu

As the world’s most polluted capital and India’s city worst affected by Covid-19, New Delhi faces grave health risks just as the nation prepares for its main festival of Diwali marked by firecrackers and mingling with friends and relatives.

Delhi’s daily Covid cases rose to a record 7,745, the single biggest count from an Indian city, as the virus infected 37,500 more people nationally. The compact Delhi state has the third-highest number of active cases, at 39,750, trailing only Kerala’s 79,528 and Maharashtra’s 96,437.

With Delhi’s Air Quality Index worsening to a severe category, the National Green Tribunal imposed a ban on firecrackers used to celebrate Diwali, the festival of lights, until the end of November. Many of these explosives are packed with chemicals that emit pollutants found to be extremely dangerous for the lungs and heart.

The National Capital Region (NCR) of Delhi, flanked by Noida, Ghaziabad, Gurugram, Faridabad and Sonipat among other urban clusters, has the highest level of pollutants in the world, according to IQAir. The capital has been on and off the dubious global top spot over the past five years.

The high level of pollution, which can cause severe breathing problems, bronchitis and other lung-related ailments, is now posing a serious threat of becoming a conduit for the Covid-19 virus, which Delhi’s health minister says is in a “third wave.’’

Ironically, the numbers of daily cases, fatalities and active cases are rising in Delhi just as they have been dropping significantly over the past month over the rest of India. Medical experts and administrators have been cautioning against the risk of another wave which could be more severe compared with earlier cases, citing global experience.

People walk along Rajpath near India Gate under heavy smog conditions in New Delhi on November 9, 2020. (Photo by Sajjad HUSSAIN / AFP)

As winter sets in north India and people crowd the bazaars for Diwali shopping, medical experts have been cautioning against a resurgence of the infection. Celebratory crackers typically add significantly to the pollution.

Research by the Chest Research Foundation in Pune showed that firecrackers commonly used by children often increase particulate matter, or PM, from 200 to 2,000 times the safe limits. The New Delhi-based Central Pollution Control Board (CPCB), recorded India’s capital Air Quality Index (AQI) value 481 of PM2.5 and PM10 at 3:00 pm local time on November 10.

The World Health Organization describes AQI of less than 50 as good air quality and less than 100 as satisfactory. Levels higher than 400 can cause severe pollution, which according to CPCB affects healthy people and seriously impacts those with existing diseases.

Over 20 million people flocking in and around NCR Delhi have been breathing toxic air for the past two weeks or so.

According to IQAir, July 4 celebrations in the United States pushed up PM2.5 across major cities. It compared air quality between July 1 and 3 and again between July 5 and 8 from 2016 through 2019 and found the increase by 915% in Las Vegas, 452% in Los Angeles, 394% in New York, 387% in Chicago and 317% in Washington.

In a landmark decision, the National Green Tribunal on November 9 banned the setting off of all kinds of firecrackers in NCR Delhi until the end of the month.

Delhi joins Rajasthan, Sikkim, Odisha, Karnataka, West Bengal and Chandigarh to ban firecrackers. India’s commercial capital Mumbai, too, has banned them, except in open, public spaces during the day of the festival and specific timings.

The state of Haryana, which borders Delhi on three sides, initially imposed a ban but later relaxed it, probably fearing a backlash.

A worker arranges firecrackers at a stall ahead of Diwali, the Hindu festival of lights, in Hyderabad on November 9, 2020. (Photo by NOAH SEELAM / AFP)

To control the runaway pollution, the tribunal recommended minimizing the use of personal transport and using more public transport, restricting travel and encouraging work from home.

It also directed the municipality to avoid burning garbage and ensure lower pollution at construction sites. The city has installed scores of water sprinklers and anti-smog guns, and has discouraged the use of coal in industries.

The key recommendation is the ban on firecrackers and the burning of stubble after crops have been harvested. Many hope the tribunal’s order can help lift the haze from the air before the festival of lights is celebrated on Saturday.