Revealed: 'Bengaluru, Chennai have breached safe air limits every year since 2021'

Bengaluru: An analysis of PM10 pollutant levels across Indian cities from 2021 to 2024 has revealed that Bengaluru and Chennai, though better off than northern cities, consistently breached the national air quality standard of 60 micrograms per cubic metre.

Researchers from Respirer Living Sciences flagged alarmingly high levels — exceeding 150 micrograms per cubic metre — in Delhi and several other cities, noting the absence of a consistent downward trend despite years of intervention at both the national and city levels.

The study identified PM10 pollution as a persistent environmental and health hazard. The four-year analysis aimed to pinpoint critically affected regions, assess contributing factors, and propose data-driven solutions.

All 11 cities analysed surpassed the permissible annual PM10 average. As expected, Delhi topped the list at 214.3 micrograms per cubic metre, followed by Patna (189.1), Chandigarh (136.9), Lucknow (118.8), and Ahmedabad (108.2).

"Seasonal variations had a major impact, with pollution levels spiking in winter due to temperature inversions and increased biomass burning. Summer months typically saw lower PM10 levels, thanks to improved atmospheric dispersion,” the study noted.

Among southern metros, Bengaluru (71.3) recorded higher pollution than Chennai (63.2), but fared better than Hyderabad (75.8), Mumbai (90), and Pune (86.8). Kolkata, though still high at 91.6, showed signs of improvement alongside Mumbai and Hyderabad.

In Bengaluru, traffic snarls on IT corridors, rampant construction, open waste burning, and dry weather were the main contributors.

Monitoring stations at Silk Board, RVCE-Mailasandra, City Railway Station and Kasturi Nagar consistently recorded high PM10 levels, while residential pockets like BTM Layout and Hombegowda Nagar also failed to meet safe annual averages over four years.

"Bengaluru’s air quality challenges have been quietly escalating, and the data now makes it undeniable. Despite its favourable climate, the city hasn’t recorded a single year of safe air. Its 'clean city' image needs a serious reality check,” said Ronak Sutaria, Founder and CEO of Respirer Living Sciences.