Kolkata: In a rare and worrying development, Kolkata has overtaken Delhi in air pollution levels, with the city recording hazardous air quality on Tuesday night.

The Air Quality Index (AQI) at Victoria Memorial -- located in the city’s Maidan area -- stood at 342 (‘very poor’ to ‘hazardous’ range), significantly worse than Delhi’s reading of 299 (‘poor’).

The unusually high AQI in the heart of Kolkata has triggered concern among environmental experts, especially since Delhi is typically regarded as the country’s pollution hotspot.

Environmental technologist Somendra Mohan Ghosh attributed the city’s worsening air quality to four unchecked pollution sources in and around the Maidan.

Speaking to IANS, Ghosh identified biomass burning, ongoing underground metro construction, older vehicles above 15 years plying on the adjacent Maa flyover, and the use of coal and firewood by roadside food stalls in the nearby Esplanade bus stand area as key contributors to the pollution spike.

“This has happened due to negligence,” Ghosh said.

“Construction is underway around Victoria Memorial, but metro rail authorities have not adopted eco-friendly practices. Regular water-sprinkling should have been carried out to settle dust. Similarly, it is the state government’s responsibility to restrict old diesel vehicles on the Maa flyover. Dust emissions from these vehicles are settling over the Maidan and creating a pollution bubble,” Ghosh told IANS.

He further criticised the lack of enforcement over biomass burning on the Maidan and the continued use of coal and firewood by makeshift eateries, which have aggravated the situation.

“The state government needs to take a firm stand. This is a serious situation that demands urgent intervention,” Ghosh said.

“Sprinkling water on trees around Victoria Memorial will help them trap more dust during winter, preventing it from circulating freely. Special attention is needed because high pollution levels pose health risks to patients at the nearby SSKM Hospital. Moreover, Victoria Memorial is a heritage precinct that must be protected,” he said further.