The Air Quality Life Index (AQLI) reveals the immense toll air pollution can have on life expectancy. India is the second most polluted country in the world and air pollution is shortening an average Indian life expectancy by 5 years, relative to what it would be if the World Health Organization (WHO) guideline fine particulate pollution (PM_2.5) of 5μg/m³ was met.

Some areas of India fare much worse than average, with air pollution shortening lives by almost 10 years in the National Capital Territory of Delhi, the most polluted city in the world. This week, we will be bringing to you 5 easy-to-digest charts that uncover the most compelling findings from India.

#1 – Five Indian states with the greatest increase in PM_2.5 pollution from 2016 to 2020

Of all the countries in the world, India faces the highest health burden of air pollution due to its combination of high PM_2.5 particulate pollution concentrations and large population. This burden has only continued to rise from 2016 2020. The Indo-Gangetic Plains of North India are the most polluted region in the country. Still, between 2016-2020, states in West and Central India experienced the most significant increase in particulate pollution concentration, as shown in this chart. Even though PM_2.5 concentration at the national level increased by approximately one µg/m³ between 2016 and 2020, in the same period, it increased by around 5 to 7 µg/m³ in Gujarat, Sikkim, Madhya Pradesh, Rajasthan, and Chhattisgarh. The increase of 9.5% to 21.1% in the particulate pollution experienced by the residents in these states translates to approximately six months more lost in life expectancy in 2020 compared to 2016.

#2 – Five Indian states with the greatest decrease in PM_2.5 pollution from 2016 to 2020

As of 2020, India’s national average particulate matter concentration was 55.7 µg/m³, roughly 11 times higher than the World Health Organization (WHO) guideline. North India, home to over half a billion people, or about 40 percent of the country’s population, remained the hotspot of air pollution. However, some states have shown to improve air quality levels.

India’s national capital happens to be one of the top five states which have made the maximum progress in reducing air pollution levels between 2016-2020. The states shown in this chart have experienced a reduction of approximately 5 to 10 µg/m3 in PM_2.5 concentration levels, which translates to six months to one year gained in life expectancy compared to 2016.

#3 – Life years lost to pollution in top 5 most polluted districts, not touched by NCAP*

In recent years, policymakers and citizens have recognized air pollution’s health threats, and the government is beginning to respond. In 2019, the Government of India launched its National Clean Air Programme (NCAP). The goal of NCAP is to reduce particulate pollution in non-attainment cities¹ by 20 to 30 percent relative to 2017 by 2024.

This figure spotlights 2020 pollution levels in the most polluted districts that are not currently covered in NCAP, and all did not meet national ambient particulate standards in 2020. The districts in this figure lie in the states of Uttar Pradesh and Bihar, two of the most populous states in India; as a result, their populations bear some of the most significant health burdens due to particulate pollution. If cities within these districts were included in the NCAP and pollution reduced by 20 to 30 percent relative to 2017, the residents of these cities could gain between 1.8 to 3.8 years in life expectancy on average.

#4 – PM2.5 pollution and life years lost in India’s top 5 most populated districts, not touched by NCAP*

Considering the growing challenge of air pollution, the Government of India rolled out the National Clean Air Programme to reduce particulate pollution in non-attainment cities by 20 to 30 percent relative to 2017 by 2024.

This figure shows 2020 pollution levels in the top five most populated districts not touched by NCAP, and all these districts did not meet national ambient particulate standards in 2020. The districts in this figure lie in the states of Bihar and West Bengal, two of India’s most densely populated states. If cities within these districts are included in the NCAP, and their 2020 pollution levels are reduced by 20 to 30 percent relative to 2017, the residents of these cities could gain between 1.5 to 3.2 years in life expectancy on average.

#5 – Pollution and life years lost in all regions lying North/South of the Tropic of Cancer

This chart displays average life years lost in North vs. South India using a partition based on the Tropic of Cancer, which cuts through India at 23.5° north of the equator. As per 2020 pollution levels, on the northern side of the partition, Indian citizens lose an average of 6.6 years of life expectancy. In comparison, those who live to the south of the line lose 3.3 years – a staggering difference of 3.3 years in average life expectancy between those who live north and south of the line. While the populations on either side of the Tropic of Cancer partition are similar, some of the poorest states in the country are found on the northern side of the line.