PM 2.5 level improves, Kol April air 3rd cleanest among Indo-Gangetic cities
Times of India | 9 May 2025
123 Kolkata: Kolkata was found to have the third best air quality among million-plus cities in the Indo-Gangetic Plain (IGP) city in April, calculated on the PM2.5 concentration in the ambient air.While the city recorded 29 µg/m³ PM 2.5 concentration, Ghaziabad emerged as the worst polluted city with 80 µg/m³ PM 2.5 level, followed by Delhi (77 µg/m³) in April, revealed an analysis by the Centre for Research on Energy and Clean Air (CREA), an independent research organisation working on trends, causes,health impacts of air pollutionand their solutions.The study shows that in April, Kolkata's air quality improved notably over the past six years. Operation SindoorOperation Sindoor: Several airports in India closed - check full listDid Pak shoot down Indian jets? What MEA saidIndia foils Pakistan's attack on Jammu airport: What we know so farThe city recorded 13 ‘good' days, when the PM 2.5 concentration in the air remained in the range of 0 µg/m³-30 µg/m³, a positive reversal from zero ‘good' days in 2024. Kolkata air in April saw 22 ‘good' days in 2020 and 21 ‘good' days in 2022. Gadag in Karnataka was India's cleanest city, with a monthly PM2.5 average of 6 µg/m³.The top 10 cleanest cities included four from Karnataka, two from Tamil Nadu and one each from Mizoram, Tripura, Andaman and Nicobar Islands and Uttar Pradesh.The number of Kolkata's ‘satisfactory' April days, with the PM 2.5 concentration in the range of 31 µg/m³-60 µg/m³ days, was 17, which is, however, fewer than 2024's 28. But this figure was consistent with the pattern in cleaner years of 2023 with 20 ‘satisfactory' days and 2021 ‘satisfactory' days. This year, April saw more ‘good' days than ‘satisfactory' days, signalling a shift towards cleaner air. Also, unlike in 2024 and 2021, this April witnessed no ‘moderate' days (61 µg/m³-90 µg/m³). In 2024, there were two ‘moderate' days and three in 2019. The data, said experts, showed that the figures did not match the exceptional levels of air quality in 2020 and 2022, but this April represented a strong recovery. This April was also the third-cleanest since 2019. But the analysis underlined the lax national ambient air quality standards, compared to the stringent World Health Organisation (WHO) standard. Manoj Kumar, an analyst at CREA, said, "India must update its National Ambient Air Quality Standards to reflect the latest scientific findings and better align with WHO's interim targets. The current standards, established more than a decade ago, are lenient and continue to contribute to significant health impacts and economic losses."Kolkata remains well within the national ambient air quality standard (NAAQS) of 40 µg/m³, yet it overshot the WHO standard by 14 µg/m³ in April.