Nagpur air pollution surged after Diwali, with PM2.5 and PM10 touching 500 and the AQI remaining in the poor category, doctors warned. One city crossed 300 and Pune’s reading is 2.5 times last year’s. Here’s the list, and why inland Maharashtra is. Nagpur: In January, the GPO observation station installed by the Maharashtra and Central Pollution Control Board recorded the highest pollution levels in Nagpur, with polluted air reported on 30.