Kolkata: Kolkata bucked West Bengal’s broader trend of improving air quality in the first half of 2026, recording a rise in fine particulate pollution even as Howrah, Asansol, Durgapur and Barrackpore registered significant declines, finds an analysis by an independent research organisation, Centre for Research on Energy & Clean Air (CREA).The city’s average PM2.5 concentration remained above India’s prescribed standard through Jan-June (H1 period). More significantly, the concentration increased from 43.6 µg/m³ during the same period of 2025. The rise interrupts Kolkata’s longer-term improvement. Its H1 PM2.5 average was 51.9 µg/m³ in 2022, suggesting that pollution levels have declined over four years.An analysis of Central Pollution Control Board data covering 272 Indian cities found that 142 cities, breached the PM2.5 standard during Jan-June 2026. Against that national backdrop, Bengal offered a mixed picture. Howrah recorded an average PM2.5 concentration of 45.4 µg/m³, down from 51.9 µg/m³ in H1 2025 and 60.3 µg/m³ in 2022. The turnaround was sharper in the industrial belt. Asansol’s PM2.5 concentration plunged from 60.1 µg/m³ in H1 2025 to 44.4 µg/m³ this year, while Durgapur improved from 50.2 to 40.8 µg/m³. Barrackpore crossed to the cleaner side, falling from 52 µg/m³ last year to 39.6 µg/m³. Haldia recorded 38.3 µg/m³, while Siliguri was at 38 µg/m³.Kolkata’s station-level data, however, reveal large variations and help explain why its overall PM2.5 average continues to remain elevated. The Rabindra Bharati University monitoring station recorded 56.1 µg/m³, the city’s highest among the stations analysed and a sharp increase from 42.4 µg/m³ in H1 2025. Jadavpur recorded 50.5 µg/m³, Victoria 50.4 µg/m³ and Ballygunge 49.2 µg/m³. Fort William was relatively better at 41.1 µg/m³.In contrast, Bidhannagar remained below the benchmark at 38.6 µg/m³, while Rabindra Sarobar was the cleanest at 34.3 µg/m³. Conditions were much worse at some locations just across the Hooghly. Ghusuri in Howrah recorded 63.8 µg/m³, the highest PM2.5 concentration among the Bengal monitoring stations.Coarser particulate pollution remains another concern. Howrah recorded an average PM10 concentration of 101 µg/m³, followed by Siliguri at 88.8 µg/m³ and Kolkata at 88 µg/m³.“For Bengal, the first-half numbers show progress in several industrial and urban centres, but also expose how uneven those gains are. Kolkata is concerning because its PM2.5 concentration increased even as several other state cities improved,” said CREA lead analyst Manoj Kumar.Durgapur/ 50.2/ 40.8/ ↓ ImprovedSiliguri/ —/ 38.0/ Below standard
