A staggering 1.5 million deaths every year from 2009 to 2019 could be tied to long-term exposure to PM2.5 pollution, according to a study published in The Lancet Planetary Health journal.

Led by teams from Ashoka University in Haryana and the Centre for Chronic Disease Control in New Delhi, it was found that each citizen of India's 1.4 billion people lives in places with PM2.5 exposure exceeding the WHO-recommended five micrograms per cubic meter annually.

How bad is PM2.5 pollution in India?

PM2.5 is actually fine particulate matter measuring less than 2.5 microns in diameter. The size of such particles is so small that they could penetrate into the lungs as well as the bloodstream.

The study discovered that an estimated 82% of India's population, which translates to about 1.1 billion people, are exposed to even higher levels of PM2.5 than the Indian National Ambient Air Quality Standards set at 40 micrograms per cubic meter. The researchers underscored that long-term exposure to such high pollution levels significantly boosts mortality rates.

What did the study find?

The team analyzed district-level data on deaths between 2009 and 2019 using the Civil Registration System. To determine annual PM2.5 concentrations, they combined satellite data with information from over 1,000 ground-monitoring stations.

One of the most disturbing results was that a 10-microgram increase in PM2.5 per cubic meter was correlated with an 8.6% increase in annual mortality.

Where is pollution worst?

While PM2.5 pollution was found across the country, the severity varied. In 2019, the cleanest air was recorded in the Lower Subansiri district in Arunachal Pradesh at 11.2 micrograms per cubic meter. On the other end of the spectrum, Ghaziabad in Uttar Pradesh and Delhi reported the highest yearly pollution levels, reaching 119 micrograms per cubic meter in 2016.

Why is this study important?

The researchers pointed out that the evidence linking long-term air pollution exposure and deaths in India has been scarce, especially compared to other countries. This new data points to the urgency to address air pollution and its deadly impact on public health.

India's alarming PM2.5 pollution levels have well exceeded global recommendations and have reflected the health risks of millions of people on a daily basis. Countless lives could be saved and overall well-being could be improved by dealing with the issue.