Delhiites lose nearly 12 years of their lives to air pollution, says report

Delhi’s annual average PM2.5 level in 2021 was found to be 126.5 µg/m3, which is more than 25 times the World Health Organization (WHO) guideline of 5 µg/m3, according to the report. In 2020, this figure was found to be a little lower at 107 µg/m3.

On account of the number of people that high particulate matter levels affect in India, the country faces the greatest health burden from air pollution among all the countries in the world. In South Asia, as in India, PM2.5 levels have seen an uptick, said the report.

“In South Asia, particulate pollution has increased 9.7 percent from 2013 to 2021…In India, PM2.5 levels rose 9.5 percent; in Pakistan 8.8 percent; and in Bangladesh, levels rose by 12.4 percent over this same time interval,” the report noted.

According to PM2.5 data for 2021 derived from satellites, pollution in India has increased from 56.2 µg/m3 in 2020 to 58.7 µg/m3 in 2021. This is more than 10 times the WHO guideline of 5 µg/m3.

The report said particulate matter pollution is also the biggest threat to human health in India in terms of lowering life expectancy, beating cardiovascular diseases and child and maternal malnutrition. While particulate pollution takes 5.3 years off the life of the average Indian, cardiovascular diseases reduce life expectancy by about 4.5 years, and child and maternal malnutrition reduces life expectancy by 1.8 years.

“The average Indian resident is set to lose 5.3 years of life expectancy if the WHO guideline is not met,” the report stated.

It identifies the northern plains (comprising Bihar, Chandigarh, Delhi, Haryana, Punjab, Uttar Pradesh, and West Bengal) as the most polluted region of the country, where the average resident could lose around 8 eight years of life expectancy if these pollution levels persist.

What could happen if PM2.5 levels are reduced?

If the PM2.5 level in Delhi is reduced to meet the WHO guideline of 5 µg/m³ as an annual average, a resident in Delhi could gain 11.9 years in life expectancy. If the PM2.5 concentration is reduced from what is the 2021 level to the national standard of 40 µg/m³, which is well below the WHO guideline, a Delhi resident could gain 8.5 years in life expectancy, the report noted.

Similarly, in India, reducing the PM2.5 level from the 2021 level to the WHO guideline could mean an increase of 5.3 years in life expectancy, while the gain would be 1.8 years if the country’s annual average PM2.5 level was lowered to meet its own standard of 40 µg/m³.

The report added: “In 2022, the Government of India revamped its NCAP (National Clean Air Programme) goal, aiming to achieve a 40 percent reduction in particulate pollution levels by 2026 in 131 non-attainment cities. Achieving and sustaining such a reduction for the 131 non-attainment cities would increase India’s national average life expectancy by 7.9 months, and by 4.4 years for residents of Delhi–the most polluted non-attainment city, underscoring the massive potential benefits.”

The AQLI, a pollution index, is based on peer-reviewed research that quantifies the relationship between long-term exposure to particulate pollution and life expectancy.