PATNA, Nov. 10 -- Air quality in Patna remained poor in the aftermath of Diwali, with the city's air quality index (AQI) recorded at 280 on Monday. Officials said this indicates continued pollution pressure despite a decline from the post-Diwali levels of previous years. Hajipur was among the country's 20 most polluted cities, ranking 16th. Its AQI of 335, the highest in the state, followed by Bettiah at 304 (ranking 27th nationally), was in the "very poor" category, according to Central Pollution Control Board (CPCB) data, shared by the Bihar State Pollution Control Board (BSPCB) at 9.20pm on Monday evening. Patna's AQI was the fifth highest among the 30 Bihar cities monitored in the post-Diwali assessment. Ara recorded an AQI of 290, while Muzaffarpur stood at 286 and Siwan at 256. The prominent pollutant in Patna and most of these cities was PM2.5, fine particulate matter that can penetrate deep into the lungs. The state-wide average AQI stood at 188, compared to 117 in 2025, marking a significant deterioration of air. P3...