LUCKNOW, Nov. 25 -- Uttar Pradesh's Hapur district emerged as the most polluted city in India on Monday, registering an Air Quality Index of 416 in the Central Pollution Control Board's (CPCB) 4 PM bulletin. It was the only city to fall in the 'severe' category among 241 monitored locations, standing out as the darkest red spot on the national air map. Delhi, often among the country's worst performers, recorded a very poor 382, still below Hapur's reading. Meanwhile, Lucknow's air also worsened, slipping back into the 'poor' bracket with an AQI of 208, the city's fifth such day this month. The last poor reading was on November 16 at 227, while the highest this month was 254 on November 5. Monday's figure marked the third-highest level for November. Most monitoring stations in the city reported poor air. Except for the Talkatora District Industrial Centre station, which recorded a 'moderate' AQI of 184. Officials said pollution levels rose due to a mix of reduced wind speed, higher vehicular emissions, and seasonal biomass burning in nearby regions. "With winter setting in, the dispersal of suspended dust and fine particulate matter has slowed," said JK Maurya, regional officer, UPPCB, Lucknow. Environmental experts caution that further declines are likely if weather conditions fail to improve. As per CPCB, an AQI of 201-300 is poor, 301-400 very poor, and above 400 severe. Several districts across western UP and the NCR also saw sharp deterioration, with many slipping deeper into the very poor category....