Bihar’s Begusarai has been identified as the world’s most polluted metropolitan area, while Delhi retains its title as the capital city with the poorest air quality, according to a recent report.
India ranks third globally in terms of air pollution, with an average annual PM2.5 concentration of 54.4 micrograms per cubic meter in 2023, trailing behind Bangladesh (79.9 micrograms per cubic meter) and Pakistan (73.7 micrograms per cubic meter). This data comes from the World Air Quality Report 2023, compiled by the Swiss organization IQAir. In 2022, India held the eighth position, with an average PM2.5 concentration of 53.3 micrograms per cubic meter.
Begusarai, previously unranked, now stands out as the most polluted metropolitan area worldwide, recording an average PM2.5 concentration of 118.9 micrograms per cubic meter. Meanwhile, Delhi’s PM2.5 levels worsened from 89.1 micrograms per cubic meter in 2022 to 92.7 micrograms per cubic meter in 2023. The national capital has consistently held the title of the world’s most polluted capital city since 2018.
The report highlights that approximately 1.36 billion people in India are exposed to PM2.5 concentrations exceeding the World Health Organization’s (WHO) recommended annual guideline level of 5 micrograms per cubic meter. Moreover, 1.33 billion people, constituting 96 percent of the Indian population, experience PM2.5 levels more than seven times the WHO annual PM2.5 guideline. This trend is mirrored in city-level data, with over 66 percent of the country’s cities reporting annual averages greater than 35 micrograms per cubic meter.
IQAir compiled this report using data from over 30,000 regulatory air quality monitoring stations and low-cost air quality sensors worldwide, operated by various entities including research institutions, governmental bodies, universities, non-profit organizations, private companies, and citizen scientists. The 2023 report encompasses data from 7,812 locations in 134 countries, regions, and territories, compared to 7,323 locations in 131 countries, regions, and territories in 2022.
Air pollution remains a critical global health threat, causing an estimated one in every nine deaths worldwide. The World Health Organization attributes approximately seven million premature deaths annually to air pollution. Exposure to PM2.5 air pollution contributes to and exacerbates various health conditions, such as asthma, cancer, stroke, and lung disease. Additionally, exposure to elevated levels of fine particles can impede cognitive development in children, trigger mental health issues, and complicate existing illnesses like diabetes.