Introduction Lung is a particularly important organ because of its interface with the environment. The environmental pollutants and endogenous reactive oxygen metabolites from inflammatory cells exert substantial pathological effects on the lung cells [1]. Oxidative stress (OS) is a major factor that plays a significant role in lung cancer (LC) [2], chronic obstructive pulmonary disease (COPD) [3] and obstructive sleep apnea syndrome (OSAS) [4, 5]. The current evidence suggests that OS takes part in the mechanisms involved in initiation, promotion and progression of respiratory diseases. The major exposures that cause OS can be summarized as smoking, and ambient air pollution that contains particulate matter smaller than aerodynamic diameter of 2.5 µm [6-8]. Epidemiological and clinical studies showed that the overall outcome of pulmonary OS is increased mortality due to increased incidence of respiratory diseases [9].