World
India
Thirteen of the world’s 20 most polluted cities are in India, with Byrnihat in Assam emerging as the most polluted globally, according to the World Air Quality Report 2024 released on Tuesday by Swiss air quality technology firm IQAir.
The report also revealed that Delhi remains the world’s most polluted capital city. While India’s overall air pollution levels declined in 2024, the country still ranks as the fifth most polluted nation globally—an improvement from its third-place ranking in 2023.
India Sees a Marginal Decline in PM2.5 Levels
India witnessed a 7% drop in PM2.5 pollution levels, with the annual average concentration falling from 54.4 micrograms per cubic metre in 2023 to 50.6 micrograms per cubic metre in 2024. Despite this improvement, six of the world’s ten most polluted cities are in India.
Delhi, which has long battled severe air pollution, recorded an annual PM2.5 concentration of 91.6 micrograms per cubic metre in 2024—showing little change from 92.7 micrograms per cubic metre the previous year.
The 13 Indian cities ranked among the world’s top 20 most polluted include Byrnihat, Delhi, Mullanpur (Punjab), Faridabad, Loni, New Delhi, Gurugram, Ganganagar, Greater Noida, Bhiwadi, Muzaffarnagar, Hanumangarh, and Noida.
Health Crisis: Pollution Cuts Life Expectancy by 5.2 Years
The alarming pollution levels in India continue to pose a significant health hazard, reducing life expectancy by an estimated 5.2 years. A study published in The Lancet Planetary Health last year estimated that between 2009 and 2019, approximately 1.5 million deaths in India annually were potentially linked to prolonged exposure to PM2.5 pollution.
PM2.5 particles—airborne pollutants smaller than 2.5 microns—pose severe health risks as they can penetrate deep into the lungs and bloodstream, leading to respiratory diseases, cardiovascular issues, and even cancer. Key sources of PM2.5 pollution include vehicle emissions, industrial output, and the burning of biomass and crop residue.
Most Polluted Countries In 2024
Chad and Bangladesh recorded the highest levels of air pollution in 2024, with average PM2.5 concentrations exceeding WHO guidelines by more than 15 times.
The WHO recommends PM2.5 levels not exceeding 5 micrograms per cubic meter, a standard achieved by only 17% of cities worldwide.
Efforts to combat air pollution face new challenges following the U.S. State Department’s decision to end its air quality monitoring program due to budget constraints. This move has removed over 17 years of data from the U.S. government’s official air quality site, airnow.gov, significantly affecting Africa’s ability to track pollution levels.
