Delhi tops the most polluted cities list, followed by Kolkata

According to a new report released on August 17, 2022, Delhi and Kolkata have the highest and second-highest levels of pollution in the world in terms of Particulate Matter (PM) 2.5, respectively. According to the report titled Air Quality and Health in Cities, the national capital had a ‘annual exposure level’ of 110 micrograms per cubic metre (g/m3), while Kolkata came in second with 84 g/m3. Mumbai came in 14th place. There are no other Indian cities in the top 20. However, Beijing had the highest disease burden from a PM 2.5-related ailment, with 124 attributable deaths per 100,000 people. Delhi ranked sixth, with 106 deaths per 100,000 people, and Kolkata ranked eighth, with 99.The report was released by HEI’s State of Global Air Initiative and published by the US-based research organisation Health Effects Institute (HEI).The study looked at data from 7000 cities between 2010 and 2019 and focused on two of the most dangerous pollutants: fine particulate matter (PM2.5) and nitrogen dioxide (NO2).Residents in India, Nigeria, Peru, and Bangladesh are exposed to PM2.5 levels that are several times higher than global averages in the 20 cities with the highest PM2.5 exposures, according to the report.In 2019, only four of these cities met the WHO annual PM2.5 Air Quality Guideline of 5 microgrammes per cubic metre (g/m3), with none in India.According to the report, while exposure to PM2.5 pollution is higher in cities in low- and middle-income countries, exposure to NO2 pollution is high in both high- and low-income cities.

By Subhechcha Ganguly