India’s Supreme Court is calling on Delhi authorities to swiftly address alarming air pollution levels that it deems as harmful as “smoking 20 cigarettes in a day.”

“Take immediate control measures. Tell us how immediately we can reduce [the Air Quality Index (AQI)] by 200 points,” Chief Justice NV Ramana told the country’s solicitor general.

Though an AQI measurement above 50 is considered harmful to human health, Delhi reached levels between 400 and 500 in almost every part of the city. Following the Supreme Court’s ruling, India’s federal administration and several northern states have 48 hours to submit plans for reducing the AQI.

“If required, think of a two days lockdown or something,” Navana said. “How will people live?”

A “thick blanket” of smog has covered the city for more than a week now, and the Supreme Court reported the judges were forced to wear pollution masks indoors, even in their own homes. The persistent smog is largely a result of cold, still conditions that allow the air pollutants to “settle in” until a wind picks up to blow them away.

The smog comes from several sources. After farmers violated bans on burning crop stubble on farms and residents used firecrackers to celebrate Diwali, AQI levels shot up as high as 627 in some areas. But the air pollution is part of a much larger problem that also traces back to India’s heavy reliance on burning fossil fuels for energy, reports Bloomberg Green. 

Taken as a whole, India’s toxic air pollution levels draw attention to the country’s climate risks, and to Prime Minister Narendra Modi’s COP 26 pledges to bring its emissions to net-zero by 2070.

“India has also committed to adding 500 gigawatts of non-fossil electricity capacity, half of energy, from renewable sources by 2030, and to increasing its carbon intensity reduction goal—measured as carbon dioxide emissions per unit of gross domestic product—from 35% to 45%, by the end of this decade,” writes Bloomberg.

The judges were critical of a Delhi administration decision to open schools earlier this month in spite of risks to children’s health. They also rebuked the solicitor general’s attempt to deflect responsibility onto farmers for agricultural crop burning, while persistently pressing the city to address its own emissions.

“Eighty per cent of pollution in Delhi is due to causes apart from stubble burning,” asked Justice Surya Kant. “What’s being done for that?”