Pollutants order changes post Covid pandemic: Cooking, industry emissions on PM2.5 rogue list
Times of India | 6 June 2025
1234 Kolkata: On the occasion of World Environment Day, the West Bengal Pollution Control Board (WBPCB) released a comprehensive report revealing how Kolkata's air pollution sources had significantly shifted in the years following Covid-19 pandemic. The analysis, drawing on two landmark studies — NEERI's pre-pandemic source apportionment study (2019) and TERI's recent post-pandemic study (2025) — shows a perceptible change in sectoral contribution to two key pollutants: PM10 and PM2.5. Significantly, only these two pollutants breach the national ambient air quality standard (NAAQS).Earlier, releasing the report, Bengal environment minister Chandrima Bhattacharya, WBPCB chairman Kalyan Rudra, additional chief secretary of the environment department Roshni Sen, former VC of Bengal Engineering and Science University (BESU) Ajay Roy, and WBPCB member secretary J P Meena emphasised how plastic pollution plays havoc with our lives and biodiversity. WBPCB chairman Kalyan Rudra declared an award for students for collecting and responsible disposal of plastic wastes through its network of 5,000-plus schools in Bengal.According to the findings, coarse particulate matter (PM10) in the city saw a decrease in dust-related emissions, from a dominant 57.3% in 2019 to 43% in 2025, suggesting possible improvements in street cleaning and construction regulation. However, this was offset by rising contributions from household cooking (from 13.3% to 18%), industry (5.9% to 12%), and vehicular tailpipe emissions (8% to 13%). Notably, refuse burning and secondary sources, which were negligible in 2019, emerged as more prominent contributors in 2025.Fine particulate matter (PM2.5), which poses graver health risks due to its ability to penetrate deep into the lungs, now sees an increased contribution from industrial emissions (7% to 21%) and cooking (27.9% to 29%). Dust emissions halved (from 24.7% to 12%), while secondary aerosols — a complex mixture formed through chemical reactions involving vehicle, industrial, and power plant emissions — came into sharp focus, now accounting for 13% of PM2.5. This rise suggests a growing influence of chemical pollutants in the city's atmosphere.The report also notes that while policies such as the introduction of BSVI vehicles and the uptake of electric mobility helped reduce PM2.5 from tailpipes (23.5% to 20%), older vehicle fleets continue to be significant emitters of PM10.