“NEW DELHI — The toxic haze blanketing New Delhi was so severe on Tuesday that politicians announced plans to close schools, flights were delayed and the chief minister of Delhi state said the city had “become a gas chamber.”

For Arvind Kumar, a chest surgeon for more than three decades, the situation is adding to a growing health crisis in the region. “I don’t see pink lungs even among healthy nonsmoking young people,” he said in a telephone interview on Tuesday. “The air quality has become so bad that even if you are a nonsmoker you are still suffering.”

The thick, acrid fog is not new to Delhi, where it settles around this time every year, covering the capital in vehicle emissions and smoke from the burning of crops in neighboring states and from fireworks from Diwali, the Hindu festival of lights. But in recent years, the problem appears to have worsened.

On Tuesday, levels of the most dangerous air particles, called PM 2.5, reached more than 700 micrograms per cubic meter in parts of the city, according to data from the United States Embassy. Experts say that prolonged exposure to such high concentrations of PM 2.5 is equivalent to smoking more than two packs of cigarettes a day.

Officials have struggled to control pollution in the National Capital Region, which includes Delhi and is home to more than 45 million people. A ban on the sale of firecrackers before Diwali in October appeared to keep the problem in check, but the illegal burning of crops, which contributes significantly to pollution at this time of the year, has just started.

The situation prompted the state’s chief minister, Arvind Kejriwal, to say on Twitter: “Delhi has become a gas chamber. Every year this happens during this part of year. We have to find a soln [solution] to crop burning in adjoining states…” The New York Times. Read the full article on Delhiair.org.

Delhi, Blanketed in Toxic Haze, ‘Has Become a Gas Chamber’