1 INTRODUCTION Smoking is a known risk factor for six of the eight major causes of death worldwide, and it is predicted that by 2030, the total number of deaths caused by smoking will exceed 8 million per year.1 Smoking increases deaths from lung cancer and chronic obstructive pulmonary disease (COPD) more than 20-fold.2 Cigarette contains more than 7000 chemicals in cigarettes, hundreds of which are toxic and have been shown by previous studies to affect almost all organ systems negatively.