Forty three per cent of the children in urban Kolkata suffer from respiratory disorders. In rural Kolkata the figure dips to 14 per cent. A study conducted by analysing the effect of air pollution on lungs of 153 children from urban Kolkata and 116 children from rural areas of the metropolitan gave these results. Chittaranjan National Cancer Institute and the Environmental Biology Laboratory of the department of Zoology, Calcutta University, had carried out the study between 1997 and 1999.

Nineteen per cent of the children were found sufferring from cough and allergic rhinitis (inflammation of the mucous membrane of the nose) was prevelant in 10 per cent cases. In rural Kolkata the figures were three per cent for cough and two per cent for allergic rhinitis (inflammation of nasal cells).

Researchers studied cells called alveolar macrophage (AM