CHENNAI: Unlike in Delhi, emissions from the industrial clusters in Chennai’s hinterland are blown away by breeze. Therefore, Chennai stands smug in the belief that it will never be a Delhi. But then, pollutants from vehicle exhaust, domestic cooking, open waste burning, and road dust are formidable enough challenges for the city.
Chennai ranks third in India in terms of the number of motor vehicles, next only to Delhi and Bengaluru. In just the last four years, an astonishing one million new vehicles were added to Chennai’s roads, taking the number up to 47 lakh.
According to a five-year study conducted by the Ministry of Environment and Forests (MoEF), the transport sector contributes a whopping 35-48 per cent to air pollution in Chennai. The study covered five other cities—Delhi, Mumbai, Kanpur, Bengaluru and Pune—and Chennai topped them all.
Since vehicle exhaust is clearly a concern, environment activist Jawaharlal Shanmugam says Chennai should ban vehicles older than 15 years because they are heavy polluters. For example, sulphur dioxide emission from a Bharat IV compliant engine is just 50 ppm compared to 500 ppm from a Bharat II engine.
However, pollution researcher Sarath K Guttikunda of UrbanEmissions.info says a transport-only anti-pollution approach is myopic. “We have to recognise that pollution comes from many sources, and transport is only one of them. We ought to look at improving the efficiency of manufacturing industries as well, especially the brick kilns,” he says.
Chennai’s average monthly concentration of PM 10 pollutants falls in the range of 60-160 micrograms per cubic metre, which is higher than the national average of 60 micrograms per cubic metre and the WHO standard of 20 micrograms. And when it comes to PM 2.5 particulates, a study conducted by urbanemissions.info found that emissions in Chennai add up to 51,200 tonnes annually.
Clearly the drift of developments indicate the need for action. National Atmospheric Research Laboratory (NARL) director R Jayaraman says, “Chennai’s case is different from the trends observed in other mega cities where overall ambient air pollution is very high. But this must not breed complacency as available data point to a steady and rapid increase in pollution over time, high local impacts and high toxicity in Chennai’s air.”
No. of vehicles
2012: 37 lakh
2016: 47 lakh
Chennai’s 7 sources of pollution
Electricity generation and utilisation
Brick kilns and construction
Open waste burning