Diesel cars driving air quality downhill in Hyderabad

HYDERABAD: The city is seeing a boom in diesel cars. Notwithstanding the spurt in high-end diesel cars for personal use in the last five years, what is staggering is the steep rise in the models of diesel variants introduced in the city. From a mere 11 diesel engine variants in 2005, a whopping 1,300 variants (approximately) were rolling on the city’s roads in 2018. That the diesel variants have set a scorching pace on city roads was corroborated by none other than the State Road Transport Authority itself. The RTA said that around 1,200 vehicles (both petrol and diesel) were being added to the streets every day.



But, what is worrying is the rise in air pollution levels which environmentalists are warning will have a serious impact on the city. The burgeoning cab industry — with as many as 3,000 to 6,000 diesel cabs added to the fleet every year — has only made matters worse.

Intermittent shooting up of all pollutants, including ground-level ozone, which is mainly caused due to vehicular emissions from diesel vehicles, has prompted the Telangana State Pollution Control Board (TSPCB) to sound an alarm. “A rise in diesel vehicles can be harmful as it indicates presence of primary pollutants like carbon monoxide, nitrogen oxide and hydrocarbons in the air,” explained R Ravinder Reddy, joint chief environmental engineer (JCEE), TSPCB.

Environmentalists said that any increase in the number of diesel vehicles will have a direct impact on particulate matter (PM), ammonia and nitrogen dioxide. “Exhaust from diesel vehicles is a major source of outdoor air pollution in the city. Emissions from diesel vehicles are of the worst kind because diesel contains more impurities and combustion percentage is less compared to petrol vehicles,” Ravinder said.

A recent study by researchers of the International Council on Clean Transportation (ICCT) had shown that 50% of pollution deaths were linked to diesel vehicles. They estimated that vehicle emissions were linked to 3,61,000 deaths worldwide in 2010, a figure which jumped to 3,85,000 by 2015.

Experts said diesel pumps out noxious oxides of sulphur and nitrogen inthe air because of its long molecular structure. Petrol engines, on the other hand, pump less of these oxides. Arun Krishnamurthy of Environmental Foundation of India (EFI) said it was hight time to discard old vehicles. “Old vehicles, both petrol and diesel, should not be allowed and pollution checks should be tightened,” Krishnamurthy said.