PM2.5 exposure reducing lifespan in Gurugram by 8.8 years, finds study

Exposure to PM2.5 — the most prominent pollutant in the city air — is potentially reducing the lifespan of the average citizen in Gurugram by 8.8 years, showed a

Exposure to PM2.5 — the most prominent pollutant in the city air — is potentially reducing the lifespan of the average citizen in Gurugram by 8.8 years, showed a recently updated study by the University of Chicago’s Energy Policy Institute. However, the interactive report (known as the Air Quality Life Index or AQLI) also showed a reduction in the annual concentration of PM2.5 in Gurugram between 2016 and 2018, leading to a relatively favourable outcome for life expectancy.

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The AQLI was first published in 2018, using available data till two years prior, i.e. til 2016. Hindustan Times had reported, on November 25, 2018, that the average reduction in life expectancy in Gurugram (due to exposure to PM2.5) was about 8.7 years. However, updated figures released on Tuesday, showed that the reduction in average lifespan at the time of the first publication of the report was, actually 11.6 and not 8.7 years. This when compared to the present estimate of 8.8 years, indicates an improvement in the life expectancy between 2016 and 2018.

The AQLI also found a 23% reduction in the annual average concentration of PM2.5 in Gurugram, from 124.7ug/m3 in 2016, to 99.4ug/m3 in 2018. Across Haryana, this figure reduced from 113ug/m3 in 2016 to 91.4ug/m3 in 2018, as per the AQLI. Nationally, too, India recorded a 10.7% reduction in the average annual concentration of PM2.5 pollutants.

As per the updated numbers, the national average reduction in lifespan due to PM2.5, according to the AQLI is 5.2 years for every Indian, while across Haryana the reduction in life expectancy is eight years.

“The AQLI converts particulate air pollution into perhaps the most important metric that exists: its impact on life expectancy,” read a press release issued along with the report. Experts said the report is an advancement from a standard Air Quality Index, which analyses air toxicity, but does not quantify its impact on human health.

In the case of Gurugram, an average lifespan reduction of 5.8 years was first calculated as per India’s National Ambient Air Quality Standards, in which the annual average safe level of PM2.5 is 60ug/m3. This number, 5.8 years, also indicates the potential gain in life expectancy if PM2.5 is brought to under 60ug/m3. In other words, Gurugram residents would add 5.8 years to their lives if the national average safe level of PM2.5 is maintained.

However, according to international standards prescribed by the World Health Organization (WHO), life expectancy in Gurugram district has more accurately reduced by 8.8 years, the AQLI suggests. Therefore, if PM2.5 was brought to a level under 10ug/m3 (the international safe limit), then citizens could potentially add 8.8 years to their lives.

Dr Piyush Goel, a city-based pulmonologist, explained that PM2.5 particles are minute enough to enter the alveoli in human lungs, where the exchange of respiratory gases takes place. “When this alien material, which comes from vehicles, construction and many other sources, enters the alveoli, the body begins to secrete mediating enzymes which cause destruction of lung tissue,” he said. These particles can even be tiny enough to pass through the alveoli and enter the blood stream, from where they get deposited in other organs, making them degenerate prematurely.

“On the whole, inhalation of PM2.5 leads to a gradual degeneration of various parts of the body, which results in accelerated aging. This is why we’re seeing younger people having chronic obstructive pulmonary disorder (COPD), heart attacks and similar other ailments,” Dr Goel said, cautioning that citizens should take care and avoid going outdoors when PM2.5 level is high, or equip themselves with appropriate protective gear, such as masks, when doing so.

Niranjan Raje, a city-based air quality expert and former member of the Supreme Court-appointed Environmental Pollution (Prevention & Control), said, “I cannot confirm the efficacy of the findings, as I am unaware of the methodology or the assumptions made in correlating PM2.5 data with life expectancy. However, India has taken several steps towards reducing particulate matter pollution in the past two years, by launching the National Clean Air Programme and enforcing Bharat Stage-6 emission norms for vehicles. If there has been an improvement, that’s a good sign. But a reduction of 8.8 years life span per person, on average, is akin to a public health crisis and means that there is a lot more work to be done.”

“Though the threat of coronavirus is grave and deserves every bit of the attention it is receiving — perhaps more in some places — embracing the seriousness of air pollution with a similar vigor would allow billions of people around the world to lead longer and healthier lives (sic),” Michael Greenstone, one of the authors of the report, from the Energy Policy Institute at the University of Chicago said in a statement.

“The reality is, no shot in the arm will alleviate air pollution. For a country like India, the solution lies in robust public policy. The AQLI tells citizens and policymakers how particulate pollution is affecting them and their communities, and can be used to measure the benefits of policies to reduce pollution,” Greenstone said.