‘Most polluted capital’ tag for Delhi again, India 3rd among countries: Report

Delhi has again earned the unenviable distinction of being the most polluted capital city in the world while Bihar’s Begusarai has emerged as the world’s most polluted metropolitan area, according to a report for 2023.

The World Air Quality Report 2023 by Swiss organisation IQAir reveals that three countries in the subcontinent had the worst air quality in 2023, with India coming third after Bangladesh and Pakistan.

Subcontinent chokes

While India had an average annual PM2.5 concentration of 54.4 micrograms per cubic metre, Bangladesh topped the list of countries with 79.9 micrograms per cubic metre and Pakistan came second with 73.7 micrograms per cubic metre.

In 2022, India was ranked as the eighth most polluted country with an average PM2.5 concentration of 53.3 micrograms per cubic metre.

Begusarai stood out as the most polluted metropolitan area globally with an average PM2.5 concentration of 118.9 micrograms per cubic metre. The city did not even figure in the 2022 rankings.

Delhi’s undesirable record

Delhi’s PM2.5 levels worsened from 89.1 micrograms per cubic metre in 2022 to 92.7 micrograms per cubic metre in 2023. The national capital was ranked the most polluted capital city in the world four times on the trot starting 2018.

It is estimated that 1.36 billion people in India experience PM2.5 concentrations exceeding the annual guideline level of 5 micrograms per cubic metre recommended by the World Health Organisation (WHO), the report said.

Also, 1.33 billion people in India — 96 per cent of its population — experience PM2.5 levels more than seven times the WHO’s annual PM2.5 guideline. This trend is reflected in city-level data, with more than 66 per cent of the country’s cities reporting annual averages greater than 35 micrograms per cubic metre.

How data was collected

IQAir said the data utilised to create this report was aggregated from the global distribution of more than 30,000 regulatory air-quality monitoring stations and low-cost air quality sensors operated by research institutions, governmental bodies, universities and educational facilities, non-profit non-governmental organisations, private companies and citizen scientists.

The 2022 World Air Quality Report included data from 7,323 locations in 131 countries, regions and territories. In 2023, those numbers have grown to include 7,812 locations in 134 countries, regions and territories.

Causing an estimated one in every nine deaths worldwide, air pollution is the greatest environmental threat to human health. According to the WHO, air pollution is responsible for an estimated seven million premature deaths worldwide every year.

Exposure to PM2.5 air pollution leads to and exacerbates numerous health conditions, including but not limited to asthma, cancer, stroke and lung disease. Exposure to elevated levels of fine particles can impair cognitive development in children, lead to mental health issues, and complicate existing illnesses, including diabetes.

(With agency inputs)