TC Web Desk
Delhi has been ranked the most polluted city in the world as per a global analysis of air quality. The report, Air Quality and Health in Cities, released by US-based Health Effects Institute on Wednesday, analyses pollution and global health effects for more than 7,000 cities around the world, focusing on two of the most harmful pollutants, fine particulate matter (PM2.5) and Nitrogen Dioxide (NO 2).
Mumbai was ranked 14th. No other Indian city features in the top 20. In terms of the highest disease burden from a PM 2.5-related ailment, though, Beijing, with 124 attributable deaths per 100,000 people was the worst. Delhi came in at 6th, with 106 deaths per 100,000 and Kolkata at 8th with 99. Five Chinese cities were in the top 20.
Delhi and Kolkata were ranked first and second in the list of top 10 most polluted cities when PM2.5 levels were compared.
The report summarizes data on air pollution exposures and associated health impacts caused by these pollutants in 7,239 cities between 2010 to 2019. Of these, 1,503 are from South Asia. The report used data from satellite imagery and ground measurements.
A large number of global cities across the world exceeded the World Health Organization’s (WHO) norms for both PM 2.5 and NO2. The report found Delhi’s average PM 2.5 exposure to be 110 micrograms per cubic metres in 2019, which is 22 times the WHO benchmark of 5 micrograms per cubic metre. Kolkata had an average exposure of 84 micrograms per cubic metres.
Shanghai had average NO2 exposure of 41.6 micrograms per cubic metres, followed by Moscow in Russia (40.2 micrograms per cubic metres). The WHO standard for NO2 exposure is 10 micrograms per cubic metres. The report said in 2019, exposure to pollutants in 86% of the more than 7,000 cities included in the report exceeded WHO’s standard, therefore impacting around 2.6 billion people.
