india

Updated: Oct 29, 2019 01:06 IST

Thousands of people in the national capital violated time restrictions and burst banned firecrackers, defying appeals from health experts, political leaders, and the Supreme Court, who urged, coaxed and ordered them to celebrate an eco-friendly Diwali in the wake of Delhi’s annual air pollution crisis.

By midnight on Sunday, the noxious fumes pushed the level of PM2.5 ultra-fine particles, which take the heaviest toll on human health among all air pollutants, to almost 18 times of what is considered safe to breathe.

The pollution, while an improvement from last year’s Diwali — when the peak PM2.5 concentration was 26 times the safe level — could be correlated with firecracker use, according to experts and data analysed by HT, suggesting the problem may have been avoided by observing the festival of lights responsibly.

“Firecrackers were the sole reason for pushing Delhi’s air quality to ‘severe’ levels this year. Government agencies had all pre-emptive measures so that we could avoid this day. Every other source was controlled; it was all in the hands of people,” said Anumita Roychowdhury, executive director (research and advocacy), Centre for Science and Environment.

“Only two varieties of green crackers — anar and phuljhari — were available this time. But they don’t produce sound. So whatever cracker-related noise Delhi heard last night was illegal,” said a senior official of the Delhi environment department, asking not to be named.

The violation was also of the two-hour window — 8pm to 10pm — set by the Supreme Court for when people could set off fireworks.

The police, however, received just 940 complaints, registered a mere 315 cases, and arrested only 166 people from across the city on Sunday night, when people across the city reported hearing firecrackers well into the early hours of the next day.

“We were acting only in cases where we were receiving complaints, rather than acting on a suo motu basis. In several cases, by the time we reached the spot, we could not identify the violators,” a senior police officer said, asking not to be named.

According to an analysis of data from government-deployed air quality monitoring stations across the city, the average hourly PM2.5 concentration was the lowest at 4pm on Sunday but started rising steadily after sunset, with a significant spike coming around 9pm when it jumped from 195 μg/m3 to 335 μg/m3.

The hourly average peaked at midnight, when the concentration topped out at 581.8 μg/m3. During this time, according to figures released by the government, the peak concentration was recorded at 1,070 μg/m3.

Slightly larger PM10 particles rose in tandem, going from 185µg/m3 around 5pm to around 1,391 µg/m3 by midnight — roughly 14 times the safe level.

On Monday, the AQI in Delhi was 368, according to the Central Pollution Control Board’s (CPCB) 4 pm bulletin. It had risen to 399 by 11pm. The figure was 372 for Gurugram and 397 in Noida.

Data analysed by HT also showed that pollution was much higher in Delhi’s residential neighbourhoods in comparison to industrial areas. A few colonies such as Aya Nagar, Ashok Vihar and Dilshad Garden registered levels that were at least 14-15 times higher than the safe limit.

The Delhi government, which made significant attempts to encourage people to refrain from banned crackers, said that the situation was better than previous years.

“Delhi has come through again. While I agree pollution is still high and needs to be further brought down, the efforts by Delhiites in last few years has led to significant reduction,” said Delhi chief minister Arvind Kejriwal, whose administration organised a laser-light show in Connaught Place to mark Diwali celebrations without fireworks.

“If the people are resolute, we can make the impossible possible,” he said, referring to the fight against pollution.

Other indicators too suggested firecracker use was lower this year. Four major government hospitals designated for treating severe burn injuries had nearly 50% fewer burn-related hospital admissions on Sunday.

Experts said weather conditions may have helped disperse pollution this year quicker than it had last year. “The dispersion of pollutants was as fast as the build-up. This is because of the stronger winds this time compared to 2018 Diwali when it took much longer for pollutants to disperse,” said Roychowdhury.

But as the levels began to taper off on Monday, weather officials warned the situation may deteriorate. “Wind speeds are expected to be low and there is a forecast of shallow fog tomorrow (Tuesday) morning. There is a possibility of the daily AQI hitting the ‘severe’ category,” said a senior scientist at India Meteorological Department, asking not to be named.

Even in 2018, while the AQI had hit 390 on the day after Diwali, it had risen to 423 the following day.

The coming fortnight has been identified as the period when the pollution problem becomes acute, according to an analysis by scientists from the Indian Institute of Technology (IIT) Kanpur.

It is in this period, the scientists said, that smoke from farm fires in nearby states drifts into the National Capital Region (NCR), while the air becomes still and heavy as the weather turns colder — creating a toxic mix in an already polluted environment.

Exposure to high levels of PM2.5 has been linked to conditions such as asthma in the short-term and diabetes, cancer and cardiac issues over a longer duration. A World Health Organization report in 2018 estimated that Indians would have lived 4.3 years longer if the 2016 air quality met global standards.