PM 2.5 levels: Kolkata achieves 21.5 per cent reduction since 2019
Kolkata: Kolkata has achieved a 21.5 per cent reduction in PM 2.5 levels since 2019 with the city’s PM 2.5 levels dropping from 57.1 µg/m³ in 2019 to 44.8 µg/m³ in 2024.
The city recorded an annual average PM 2.5 level of 44.8 µg/m³ in 2024, making it one of the best-performing metropolitan areas in India under the National Clean Air Programme (NCAP) framework, according to a recent report. Kolkata’s air quality in 2024 was better than Delhi (107.0 µg/m³) and Mumbai (36.1 µg/m³), reflecting the success of target interventions.
“Kolkata has demonstrated one of the strongest performances among metropolitan cities, aided by initiatives such as improved compliance with emission norms for industries in and around Kolkata, investments in public transport, including Metro expansions, have reduced vehicular emissions, urban afforestation initiatives and the preservation of wetlands have contributed to better air quality,” said an official in the state Environment department.
According to the report ‘Towards Clear Skies 2025’ using data from the AtlasAQ Platform, by Respirer Living Sciences, on the sixth anniversary of the NCAP, regional hotspots and seasonal spikes during winter months underscore the need for continued efforts to sustain this progress.
“Kolkata’s consistent improvements demonstrate the impact of stricter industrial regulations and enhanced public transport, but the city’s high population density and seasonal pollution spikes remain areas of concern,” said Ronak Sutaria, Founder of Respirer Living Sciences.
However winter months, particularly December and January, saw PM 2.5 levels frequently exceeding 90 µg/m³, driven by low wind dispersion and increased emissions from heating and transport stressing the need for addressing localised hotspots and seasonal patterns to ensure sustained air quality improvements.
Kolkata remained in the “moderate” pollution category, performing significantly better than other cities. However, localised challenges and season spikes during winter months continue to pose issues, particularly in densely populated and industrial areas.
In Howrah and surrounding industrial areas, high industrial density and vehicular congestion resulted in PM 2.5 levels frequently exceeding 65 µg/m³, well above the city’s average. Urbanisation and unregulated waste burning contributed to pollution spikes, impacting the air quality in surrounding neighbourhoods of Topsia and East Kolkata Wetlands while heavy traffic congestion during peak hours caused periodic spikes, particularly during weekdays in central business districts like Esplanade and Dalhousie.
The report has called for localised emission controls like strengthening, monitoring and enforcement in pollution hotspots like Howrah and industrial zones, addressing winter spikes by implementing targeted measures during winter months, including stricter vehicular regulations and public advisories, promoting clean technologies through encouraging the adoption of cleaner fuels and technologies across residential and commercial sectors.
