Bengaluru’s annual PM2.5 levels exceed WHO guidelines by 6 times

Soumik Dutta | NT

Bengaluru: The average pollution levels in ten major South Indian cities far exceeds the latest World Health Organisation standards of 5 µg/m3, a study shows. A report by Greenpeace India analysing the Central Pollution Control Board’s data between November 2020 and November 2021 is a much-needed reminder that air pollution is a public health crisis that is not confined to cities only in North India.

Coimbatore, Bengaluru, Mangaluru and Amravati all saw annual PM2.5 (atmospheric particulate matter that has a diameter of less than 2.5 micrometres) levels exceed WHO guidelines of 5 µg/m3 by six to seven times. Air pollution data from ten cities – Bengaluru, Hyderabad, Chennai, Amravati, Vishakhapatnam, Kochi, Mangaluru, Puducherry, Coimbatore and Mysuru – was selected and analysed based on the availability of data, population and monitoring station networks.

The report found that despite pandemic-induced lockdowns and subsequent reduction in economic activities, the annual average values of PM2.5 and PM10 (particulate matter in the air with a diameter of 10 micrometres or less) exceeded WHO’s revised standards by many folds. While annual PM10 levels in Bengaluru exceeded the prescribed WHO standards of 15 µg/m3 by three to four times. The annual PM2.5 levels were found to be six times the WHO prescribed limit of5 µg/m3.

The primary contributors to worsening the air quality are fossil fuel powered infrastructural development, industries, transport, waste burning and construction activity, the report stated. Chronic exposure to air pollution increases the likelihood of asthma, low birth weight, depression, schizophrenia, diabetes, stroke, lung cancer and can cause premature deaths. The Karnataka State Pollution Control Board has stated that the biggest cause of PM2.5 in the Bengaluru air is due to the ongoing construction activities.

In Bengaluru, there are 10 monitoring stations under the guidelines of the Central Pollution Control Board (CPCB) and the Karnataka State Pollution Control Board (KSPCB), five in the commercial sectors of BTM Layout, Bapuji Nagar, Hombegowda Nagar, Jayanagar 5th Block and Saneguruvanahalli, and another five in the industrial sectors of Hebbal, Silk Board, Peenya and Kadubeesanahalli. The annual average values of PM2.5 and PM10 show that at all the locations, the values are higher than the WHO revised standards.

“We have to prioritise the immediate shift to clean energy and clean transport to stop more damage. If we look at Bengaluru’s PM10 data, the annual average in most stations is exceeding not only the WHO guidelines, but NAAQS levels too,” Avinash Chanchal, Campaign Manager of Greenpeace India said. “The pollution control boards must realise that no level of air pollution is safe and even the long-term exposure of lower levels of concentrations of air pollution can severely impact human health,” he added.

The Greenpeace report mentioned that the CPCB must revise the current national ambient air quality standards for all pollutants based on WHO’s proposed interim target, and gradually achieve the revised standards. On analysing the air quality data from the Berkeley Earth Project report, Bengaluru’s air quality is seen to have worsened by 3 per cent in 2021 compared to 2020. This leaves Bengaluru with air pollution levels six times higher than the WHO’s annual limit.

The data shows that 2021 Bengaluru air quality was worse across the whole year, except briefly in summer. Analysing the air quality data for the previous five years suggests that Bengaluru’s pollution levels start peaking in winter, with PM2.5 typically rising in October, and it remains high until March of the following year.

Despite being better than Delhi and Kolkata, Bengaluru’s PM2.5 exceeds the WHO’s annual limit every month of the year, even in the cleanest month. According to the Greenpeace report, particulate matter (PM) 2.5 had claimed 12,000 lives in Bengaluru alone in 2020. In Delhi, 54,000 lives were lost in the same year revealed by the Greenpeace Southeast Asia analysis of IQAir data from a live cost estimator.

The KSPCB stated that the biggest cause of PM2.5 is the ongoing construction activities. Despite Rs 279 crore being given to BBMP by the Ministry of Environment, Forest and Ecology and Climate Change (MoEFCC) under the National Clean Air Mission to mitigate air pollution, little can be seen on ground