Mumbai has an average annual PM 2.5 concentration more than four times the World Health Organisation (WHO)’s limit and is the 169th most polluted city in the world, says a new report published on Tuesday.
According to the IQAir AirVisual’s World Air Quality Report, 21 of the 30 most polluted cities in the world are located in India with Ghaziabad in the National Capital Region ranked the world’s most polluted. However, Indian cities have shown improvement in air quality over the past year, the report says.
Among countries, India is the fifth most polluted country in the world. Bangladesh tops the list, followed by Pakistan, Mongolia and Afghanistan.
The majority of the most polluted cities and countries are in the South Asia region, the report says.
Mumbai’s annual PM 2.5 concentration — particles smaller than 2.5 microns in diameter, smaller than human hair — is 45.3 micrograms/cubic metre, when it should be 10 micrograms/cubic metre according to WHO’s PM 2.5 standards.
While cities in India, on average, exceed the WHO target for annual PM 2.5 exposure by 500 per cent, national air pollution decreased by 20 per cent from 2018 to 2019 with 98 per cent of cities experiencing improvements. As compared to 2018, every city in India except Nagpur saw a decrease in PM 2.5 levels in 2019, the report says.
The data for Mumbai reveals that January 2019 saw the highest monthly average concentration of PM 2.5 at 104.5 micrograms/cubic metre. The lowest monthly average concentration of PM 2.5 in Mumbai was recorded in September at 12.6 µg/m3.
However, these improvements may not be fully representative of the “very recent but promising” National Clean Air Programme and the introduction of cleaner fuel Bharat VI, but are more indicative of a slowing of the marketplace, the report says.
The report’s conclusions are based on PM 2.5 data collected from global monitoring stations in 2019.
The data represented has been aggregated primarily in real-time by IQAir AirVisual platform along with historical datasets.
Some PM 2.5 data has also been compiled from thousands of initiatives run by people, communities and companies through validated low-cost sensors. Many of these stations represent the only available, real-time air quality information for their area, the report says.
📣 The Indian Express is now on Telegram. Click here to join our channel (@indianexpress) and stay updated with the latest headlines