The impacts of physical activity levels on the deposition and transportation of air pollutants of different sources in the human lungs

The effects of air pollutants on the human lungs' health are significant and are becoming increasingly alarming in megacities. The most common pollutants are dust, traffic emissions, and smoke. In this paper, the deposition and transportation of these pollutants of sizes ranging from 2 μm to 10 μm under various physical activity levels in a realistic human lung model are investigated numerically. Three realistic breathing profiles representing three physical activity levels, Eupnea (rest), Walking, and Hyperpnea (exercise), are investigated. It is revealed that, in addition to the pollutant size and type, the physical activity level is vital in determining the deposition rate and location of the pollutants in the upper respiratory tract (URT). For instance, the deposition rate of 7 μm dust is 70 % under the Hyperpnea condition; however, this value is 23 % under the Eupnea condition. This study presents a clear picture of how and to what extent the physical activity levels can affect the damage from the pollutants of different sizes and types to the human lungs. The outcomes of the presented research can benefit the preventive actions in reducing the damage to individuals' lungs and the prognosis of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD).