Every 10 microgram per cubic metre increase in PM2.5 concentration led to an 8.6 per cent increase in mortality, revealed a study conducted by researchers from five countries
Around 3.8 million deaths between 2009 and 2019 in India can be linked to air pollution, based on the country's threshold for acceptable limits of PM2.5 (40 micrograms per cubic metres), according to a recent study published by The Lancet Planetary Health.
The study, conducted by researchers from universities in India, Sweden, US, Israel and Italy, also said that if we were to go by the stricter guidelines set by the World Health Organisation (WHO), the number of deaths could rise to 16.6 million. This, the study notes, is almost 25 per cent of all mortality during 2009-2019.
According to one of the authors of the study, “every 10 microgram per cubic metre increase in PM2.5 concentration led to an 8.6 per cent increase in mortality." The study is based on data from 655 districts in India and analyses the link between PM2.5 particles and mortality over a ten-year period.
According to the researchers, 1.1 billion people or nearly 82 per cent of India's population live in areas where PM2.5 levels exceed the Indian National Ambient Air Quality Standards. However, going by WHO standards, 1.4 billion, or all of India, are exposed to the negative effects of air pollution.
What is even more alarming is that some regions recorded PM2.5 levels of up to 119 micrograms per cubic metres, significantly higher than what is considered safe by both WHO and national standards, during the same period.
“The results show that current guidelines in India are not sufficient to protect health. Stricter regulations and measures to reduce emissions are of utmost importance,” said Petter Ljungman, last author and researcher at the Institute of Environmental Medicine, Karolinska Institutet, Sweden.
“Our study provides evidence that can be used to create better air quality policies, both in India and globally,” Ljungman added.
The minimum concentration of PM2.5 levels was observed in the Lower Subansiri district in Arunachal Pradesh in 2019 and the maximum of 119 micrograms per cubic metres was observed in Ghaziabad in Uttar Pradesh and Delhi in 2016, said the report.
Air pollution consisting of particles smaller than 2.5 micrometres in diameter or PM2.5 can enter the lungs and bloodstream and is a major health risk in India. Despite several measures undertaken by the Indian government to mitigate air pollution and its harmful effects, poor air quality continues to be an ongoing concern. Year after year reports of cities and regions are affected by smog, health issues related to air pollution.
As far as policy measures are concerned, researchers of the study have called for reducing emissions locally while keeping in mind the long range of air pollution in the country.