Why do Smoker's Lung Look Black?

Extended exposure to airborne irritants, such as cigarette smoke, can cause lasting damage to the lungs and respiratory tract. Cigarette smoke contains impurities that, when inhaled, trigger an immune response from macrophage cells. Macrophage cells are responsible for engulfing and digesting foreign and harmful particles. In the lungs of smoker's macrophages trap tar and debris, making the lungs appear black. Smoking is the leading cause of chronic obstructive pulmonary disease (COPD) is an airflow-limiting condition that affects the lungs. Common symptoms of COPD include shortness of breath, fatigue, and coughing.