Calcutta tops the country in exposure to toxic vehicular pollution, according to the findings of a study that transport experts from India and other south Asian countries discussed in Delhi on Thursday.
The findings of the study — conducted by Apte, Bombrun, Marshall, & Nazaroff — were reported in the paper “Global intra-urban intake fractions for primary air pollutants from vehicles and other distributed sources”, published in the journal Environmental Science and Technology in 2012.
Calcutta’s exposure to toxic vehicular pollution — measured as grams of pollution inhaled per gram of pollution emitted — was found to be 150.
The higher the value, the greater is the exposure. The next in line is Delhi (100).
India’s national average is 51, against the global average of 39. China, infamous for its poor air, has an average exposure factor of 45.
“Calcutta fares poorly when it comes to exposure to toxic vehicular pollution. It’s unthinkable that the city is banning non-motorised vehicles like cycles when the vehicular pollution exposure is skyrocketing,” said Sunita Narain, the director of non-profit Centre for Science and Environment (CSE).
Anumita Roy Choudhury, a transport expert associated with the CSE, pointed out that Calcutta’s public transport was in poor state despite some pluses like “proactive parking strategy”, “popular” waterways and trams.
“The combination of consistently high level of fine particulate matter and nitrogen oxides, mainly emitted by diesel-powered and ill-maintained commercial vehicles, is the city’s bane,” Roy Choudhury told Metro.
Calcutta was better placed than several other cities in green air criteria following the 2008 high court ban on two-stroke autos and commercial vehicles 15 years or older.
“But the situation is back to square one because of complete inaction in enforcing the court order over the past three years. Not a single auto was replaced or an old commercial vehicle withdrawn during this period,” said environment activist Subhas Dutta.
Findings of a study by the Central Pollution Control Board and CSE, also presented at the Delhi meeting, show how Calcuttans are suffering because of high level of exposure to vehicular pollution.
Scientist Manas Ranjan Roy of Chittaranjan Cancer Hospital in Calcutta, who has been studying the effects of vehicular pollution on humans, said studies have shown that toxic air pollutants affect the lungs, heart, liver, kidney, neuro-system and immunity as a whole.
“It’s a killer cocktail,” said Roy.
During the programme, the CSE released a book —Good News, Bad News: Clearing the Air in Indian Cities — that highlights the reasons for the particulate pollution level in 78 per cent of cities in the country exceeding the national average.