In 1995, a study published by the World Bank had concluded on the basis of 1992 data that 863 people were died prematurely due to air pollution in Chennai every year. Chennai had a population of about two million then. Now, just seven years down the line, a new study estimates that more than 200 people are dying prematurely every year, in just one small municipality of North Chennai called Thiruvottiyur, which has a population of 0.211 million living in an area of 21.42 square km.

Researchers at the Chennai-based Sri Ramachandra Medical College and Research Institute conducted the analysis. They found that particulate matter of size less than 10 micron (PM10) poses one of the greatest risk to public health. More than 80 per cent of the people studied had been exposed to 100 microgramme per cubic metre (