With the National Green Tribunal (NGT) banning more than 10-year-old diesel vehicles from plying in the city, environment experts in the national Capital feel that if diesel cars are affecting the air health so much why is the ban imposed only in the CapitalIJ
“It is a knee-jerk judgment by NGT. The green panel is just taking care of the health of capital residents. But what about the health of people who are living far from National Capital Region (NCR),” said Gopal Krishna, Environmentalist, Anti-Toxic Watch Alliance (ATWA).
Krishna added that diesel-related pollutants are either already very high or rapidly increasing in Delhi’s air and in other Indian cities. “Both particulates and nitrogen dioxides have emerged as pollutants of concern in Indian cities, the issue is not just reserved up to NCR boundary,” said Krishna.
In a recent study of Centre for Science and Environment (CSE), total numbers of diesel cars in 1995 were 20,000 which escalated to 12,00,000 in 2006.
When asked how diesel vehicles contribute more in polluting the air of the city, he said that the contribution of diesel emissions to fine particulate matter, oxides of nitrogen and other carcinogens like polycyclic hydrocarbons should not be underestimated. “Sulphur dioxide (SO2) and nitrogen oxides from diesel vehicles also contribute significantly towards the build-up of secondary particulates and Ozone. And this has been scientifically proved that the particulate emissions from uncontrolled diesel engines, which are six-ten times greater than those from petrol engines,” he added.
According to the CSE report on carcinogens elements, the extremely tiny diesel particles go deep into the lungs and are also very toxic. Notably, diesel vehicles emit lower carbon monoxide (CO) and hydrocarbons (HCs) compared to petrol vehicles.
The air quality data from the Central Pollution Control Board (CPCB) shows that more than half of cities monitored in India have recorded critical levels of Particulate Matter (PM) 10 levels. While in the Capital, the daily levels of tiny particles less than 2.5 micron size have reached more than 800 microgram per cubic meter in October and November month.
Not only the PM, but the levels of nitrogen dioxides (NO2) have been increasing in the city to dangerous levels (reaching up to 300 micro gram per cum), which is a clear sign of pollution from vehicles.
The CSE report further stated that the ground level Ozone, known to be extremely hazardous for human health, is poorly assessed in India. But limited data indicates higher number of days violating the WHO guidelines in summer of this year in Delhi.