Kol’s PM2.5 count improved by 21.5% over 5 years, shows study
Times of India | 8 January 2025
12 Kolkata: The city has achieved a 21.5% reduction in PM2.5 levels over the past five years, with annual averages improving from 57.1 µg/m³ in 2019 to 44.8 µg/m³ in 2024, according to the report ‘Toward Cleaner Skies: An In-Depth Analysis of Air Quality Improvements in Indian Cities (2019-2024)' released on the sixth anniversary of the National Clean Air Programme (NCAP).
The progress notwithstanding, challenges like seasonal pollution spikes during winter and localised hotspots in industrial and densely populated areas continue to pose significant obstacles to sustained air quality improvement.
The report, published by Respirer Living Sciences, an environment and climate-tech start-up using data from the AtlasAQ Platform, highlights Kolkata as one of the top-performing metropolitan cities under NCAP, with air quality trends demonstrating the effectiveness of targeted interventions. Yet, winter months remain a concern, with PM2.5 levels often exceeding 90 µg/m³ due to low wind dispersion, increased emissions from heating, and traffic congestion.
Kolkata's strides in reducing pollution reflect the impact of stricter industrial regulations, expanded public transport options, and green initiatives, yet high population density and unregulated emissions remain persistent challenges, according to Ronak Sutaria, founder of Respirer Living Sciences. "While Kolkata's consistent improvements are commendable, localised hotspots and seasonal patterns must be addressed to ensure long-term progress," he said.
In 2024, Kolkata outperformed many metros, maintaining its position in the ‘moderate pollution' category. Compared to Delhi's average PM2.5 level of 107.0 µg/m³ and Mumbai's 36.1 µg/m³, Kolkata's 44.8 µg/m³ was a significant achievement. However, the city's dense urban environment and industrial zones, like Howrah and Topsia, experienced recurring pollution spikes, with PM2.5 levels in some areas surpassing 65 µg/m³.
Under NCAP, Kolkata's air quality improvements were supported by stricter industrial regulations, expanded public transport, and urban afforestation. But to achieve the 40% reduction target by 2026, further measures are necessary, particularly during winter and in pollution-prone areas, the report said.
Recommendations for sustained progress include strengthening localised emission control by enforcing stricter regulations in pollution hotspots, addressing winter pollution through measures like stricter vehicular regulations, enhanced public transport options, and public advisories during high-pollution months, promoting the adoption of cleaner fuels and technology across residential and commercial sectors to reduce overall emissions, and increasing public awareness through campaigns focused on educating citizens about waste management practices and their critical role in improving air quality.