8. Lucknow, North India
> Population: 3.2 million
> Average annual PM2.5 pollution per cubic meter: 138.4 micrograms
> Average annual PM10 pollution per cubic meter: 254.9 micrograms
7. Delhi, North India
> Population: 25.7 million
> Average annual PM2.5 pollution per cubic meter: 143.1 micrograms
> Average annual PM10 pollution per cubic meter: 292.3 micrograms
6. Patna, East India
> Population: 2.2 million
> Average annual PM2.5 pollution per cubic meter: 144.3 micrograms
> Average annual PM10 pollution per cubic meter: 265.7 micrograms
5. Varanasi, North India
> Population: 1.5 million
> Average annual PM2.5 pollution per cubic meter: 146.3 micrograms
> Average annual PM10 pollution per cubic meter: 260.1 micrograms
4. Gaya, East India
> Population: 508,000
> Average annual PM2.5 pollution per cubic meter: 149.1 micrograms
> Average annual PM10 pollution per cubic meter: 274.6 micrograms
