Coal, diesel emissions bigger killers in New Delhi than dust

The emissions from diesel vehicles, thermal power plants and coal-based industries are much more deadly than the farm stubble or dust haze that has enveloped the national capital.

People commute through dense smog in New Delhi. | PTI

NEW DELHI: The emissions from diesel vehicles, thermal power plants and coal-based industries are much more deadly than the farm stubble or dust haze that has enveloped the national capital over the past few weeks.

According to a study done by the Environment Pollution (Prevention and Control) Authority (EPCA), a Supreme Court-appointed pollution watchdog, particles released by combustion of coal and diesel are more harmful than wind-blown dust as they can lead to an increase in heart disease-related deaths.

This week only, Delhi Lieutenant Governor Anil Baijal had withdrawn the ban on the entry of diesel trucks in the city.

Studies and research reports have underlined that it’s the chemical composition of ultrafine particulates PM2.5 or PM10, and not their volume, which is more crucial in determining the toxicity of air.

“Similarly, particles from diesel combustion are very toxic and have been classified by the World Health Organisation as Class I carcinogen for strong links with lung cancer, putting them in the same bracket as tobacco smoking and asbestos. This suggests that we must prioritise the more harmful particulates for action. Combustion sources --- vehicles, power plants and industry --- need more stringent and priority action,” the report says.

An Indian Institute of Technology-Kanpur report has also backed the EPCA’s latest report. IIT-Kanpur assessed the chemical composition of pollution from various sources in the city and concluded that combustion, vehicular and industrial alike, was responsible for the formation of PM2.5 in greater quantity.

Between PM2.5 and PM10, the most dominant pollutants in Delhi’s air, PM2.5 is deadlier owing to its tinier size – up to 30 times smaller than the width of a human hair. The ultrafine particles get lodged deep in the lungs and subsequently enter the bloodstream.

The EPCA’s latest report contradicts earlier studies done by various NGOs which had concluded that dust plays a bigger role in polluting Delhi air than vehicular emissions.