
The objective of this study was to assess the effect of chemical particle present in cigarette smoke on ventilatory functions on smokers to analyse the extent of impairment in the airways. Parameters recorded were PEFR, FEV1, FVC, FEF25-75% and FEV1/FVC%. For each participant chest X-ray was also taken. We have done comparison of ventilatory functions in non-smokers and smokers. It was observed that the values PEFR, FEV1, FVC, FEF25-75% and FEV1/FVC% significantly decreased in smokers (p value<0.001) when compared to non-smokers. Smokers are at high risk of developing obstructive lung disease. Tobacco smoke contains abundant reactive oxygen “Free radical” which deplete antioxidant mechanism thereby inciting tissue damage. Activated neutrophils also added to the pool of reactive oxygen species in the alveoli. The free radical causes inflammation which results in narrowing of airways.