While industries, power plants, mines and vehicles are blamed for increasing exposure to air pollution, there are many lesser-known sources which are significantly poisoning the quality of air. VirendraSethi, professor at Centre for Environmental Science and Engineering, Indian Institute of Technology, Bombay, whose 40 research papers have been published in various international journals, talks about what really is adding to rural and urban air pollution.
Q. Which are the unaddressed factors that cause urban air pollution?
A. It is easy to blame industries or vehicles because we see those releasing pollutants. But there are other unseen sources too. Pollution caused due to smoke emitted from a truck is less than that caused when it raises suspended dust particles on road. In a movie theatre, the air-conditioner keeps recirculating the same air, shooting up the carbon dioxide levels. Same happens in case of split ACs. Suspended dust particles, burning of agricultural waste, burning garbage at landfill sites, use of solid fuels are contributing immensely in urban air pollution.
Q. Are practices like Delhi's odd-even plan or diesel-free vehicles useful?
A. Odd-even formula did help in reducing air pollution. When number of vehicles is decreased, it will naturally bring down the carbon footprints. Switch over from diesel to Compressed Natural Gas (CNG) has also helped in improving air quality. But before taking decisions like banning diesel vehicles, it is important to scientifically study their contribution to air pollution. Not much research is being done on these lines.
Q. Is indoor air pollution more worrisome? How is it taking a toll on rural health?
A. By the time smoke released from chimneys reach us, it gets diluted with clean air. But in a typical rural household where women use stoves in closed kitchens, the situation is far more serious as they are directly exposed to high emissions. The smoke remains suspended in the small rooms and people actually sleep in highly polluted air. This is why a large percentage of rural population suffers from respiratory problems and other diseases.
Q. Are agencies like state pollution control board doing enough to curb pollution?
A. Their intention is good but they don't have the capacity and resources to deal with problems. Rigorous and detailed studies are need of the hour.
Q. Despite having less population density, some two-tier cities are highly polluted. Nagpur too was ranked as the sixth most polluted city of the state and 49th in the country by WHO.
A. It is a myth that pollution is completely dependent on population or number of vehicles in a city. There are various other factors that degrade a city's ambient quality of air. In case of Nagpur, it is surrounded by thermal power stations in Koradi, Khaparkheda, Butibori, Mauda and industries in Hingna and Butibori. Depending on the wind direction, pollutants from all these sources come in the city, this increasing it pollution levels
