Kolkata, 25 October 2026: An analysis of air-quality records has raised a warning for Kolkata before the winter pollution season even begins. Researchers with the Centre for Research on Energy and Clean Air (CREA), using Central Pollution Control Board monitoring data, calculated an average PM10 level of 76 micrograms per cubic metre (µg/m³) from 1 January to 16 October 2026. That compares with 72 µg/m³ during the equivalent period in 2025.
What does the PM10 benchmark mean?
India’s annual PM10 limit is 60 µg/m³. CREA’s calculation showed that Kolkata had accumulated sufficient particulate pollution by mid-October to breach the full-year annual benchmark even if PM10 exposure fell to zero for the remainder of the year. This is a cumulative calculation and should not be confused with a claim that today’s AQI is at any particular level.
PM10 refers to airborne particles with diameters up to 10 micrometres. Sources can include road dust, construction activity, industrial processes and combustion. Long-term exposure is relevant to respiratory and cardiovascular health.
Why winter brings added concern
As temperatures fall and atmospheric mixing weakens, pollutants can remain closer to street level. Researchers cautioned that the city is entering its traditionally more polluted months with an already elevated year-to-date average.
The World Health Organization’s annual PM10 guideline is 15 µg/m³, substantially tighter than India’s national standard. These standards are different reference points; neither is a personalised medical threshold for an individual.
What would help Kolkata?
Better road-dust control, enforcement at construction sites, cleaner vehicles, waste-burning prevention and transparent pollution-source monitoring are among the policies that merit attention. Residents with respiratory concerns can follow official daily AQI alerts and consult clinicians for individual precautions.
Mojo Pulse perspective: Air pollution cannot be judged by one spectacularly bad winter morning. A city’s accumulated exposure across the year is the bigger governance test.
Sources and reporting basis
Original Mojo Pulse reporting synthesis based on the sources cited below; developments may evolve.
