Delhi world's most polluted major city on eve of Diwali, Swiss group says

Delhi has been deemed the world's most polluted major city on Saturday morning, as reported by Swiss environmental monitoring group IQAir. The Indian capital is bracing for severe air quality conditions a day before Diwali, the Hindu festival of lights. In response to the impending pollution, schools in and around Delhi have been urged to provide online classes, while authorities have encouraged residents to work from home.

According to IQAir's live ranking, Delhi secured the top spot among major cities at 10:35 a.m. (0505 GMT) with an US Air Quality Index reading of 581. This figure is double that of Lahore, Pakistan, which scored 285. It is important to note that IQAir's reading, which is based on concentrations of air pollutants, is not directly comparable to India's official index. The latter utilizes a distinct scale and methodology.

On Friday, Delhi's air quality index was recorded at 363, placing it in the "very poor" category, according to India's Central Pollution Control Board. Local media sources have highlighted that Friday's air quality in Delhi was the worst pre-Diwali air in eight years, based on official data. Pollution is a recurring issue in several regions of northern India during the onset of winter.

As the cold, heavy air becomes trapped, it concentrates vehicle emissions, construction dust, and smoke from the burning of crop waste, exacerbating the air quality crisis.