High particulate matter reducing Delhi life expectancy by 8.2 years: Report

The 2025 report is based on an analysis of pollution data from 2023. While Delhi’s annual PM2.5 concentration in 2023 was 88.4µg/m3, it was 41µg/m3 for the entire country

Hazardous levels of finer particulate matter (PM2.5) is bringing down, on average, life expectancy of Delhi residents by 8.2 years, according to a report released on Thursday. It said that the loss could be mitigated by adhering to the World Health Organization’s (WHO’s) standard of 5 micrograms per cubic metre (µg/m3), whereas adhering to the national limit of 40µg/m3 still reduces life expectancy by 4.7 years.

The study said that the loss could be mitigated by adhering to the World Health Organization’s (WHO’s) standard of 5 micrograms per cubic metre. (Representative photo/HT Archive)

Across the country, high PM2.5 levels are bringing down life expectancy by 3.5 years, it said. The report, which shares the Air Quality Life Index (AQLI) of residents of different cities across the world, is released by the Energy Policy Institute at the University of Chicago (EPIC) every year.

The 2025 report is based on an analysis of pollution data from 2023. While Delhi’s annual PM2.5 concentration in 2023 was 88.4µg/m3, it was 41µg/m3 for the entire country.

“According to the latest satellite-derived PM2.5 estimates, in 2023, particulate concentrations in India were higher than in 2022. These levels are more than 8 times higher than the WHO guideline, and reducing them to permanently meet the WHO Guideline would add 3.5 years to the average life expectancy of Indians,” the report said, highlighting that Delhi was the worst-impacted city in India.

The AQLI quantifies the causal relationship between long-term human exposure to air pollution and life expectancy, which is based on a pair of peer-reviewed studies. By comparing two subgroups of the population that experienced prolonged exposure to different levels of particulate air pollution, the studies were able to plausibly isolate the effect of particulate air pollution from other factors that affect health.

After the Capital, the biggest loss in life expectancy is in Bihar (5.4 years), Haryana (5.3 years) and Uttar Pradesh (5 years), the report said. In the northern plains, 544.4 million residents or 38.9% of the country’s population could gain an average life span of 5 years, adhering to WHO standards, or 1.6 years by adhering to the national standard.

The report said that the entire 1.4-billion Indian population is affected by higher PM2.5 levels. “This means that even people living in the cleanest regions of India could live 9.4 months longer if particulate concentrations in these regions were reduced to meet the WHO guideline,” the report said.

The report highlighted that 46% of the population lived in areas where the pollution exceeded the annual national standard of 40 µg/m³. “Reducing particulate concentrations in these regions to meet India’s national standard could add 1.5 years to the life expectancy of people living in these regions,” it said.

Tanushree Ganguly, director of Air Quality Life Index and co-author of the report, said the data and findings were particularly stark for Delhi.

“Consistent exposure to the levels seen in Delhi over the past five years suggests that residents could lose up to 8 years of life if such conditions persist. Pollution reduction in Delhi must therefore be guided by strict concentration reduction targets,” she said.

“To meet India’s national standard of 40 µg/m³, the city would need to cut particulate concentrations by more than 50%. Doing so could add over 4.5 years to the life expectancy of the average Delhiite. Research shows that about 50% of Delhi’s pollution comes from local sources and controlling these sources alone could therefore help meet national standards,” she said.

Assessing only the National Capital Region (NCR), the report said a drop in pollution by 26% was needed to meet the national standard, which would add 1.4 years to life expectancy. The NCR districts would have to reduce their PM2.5 levels by 44% to meet the WHO standards, which would add 4.8 years to the average life expectancy of residents.

Last year’s annual AQLI report, based on 2022 readings, found life expectancy reduced by 7.8 years, based on then PM2.5 reading of 84.3µg/m3.