Inhaling cigarette smoke irritates the tissues along the trachea, according to Healthline. Known as the respiratory mucosa, this tissue creates mucus when irritants contact it. Over time, the mucus catches tar coming from cigarettes, and the gunk hinders the filtration of debris out of the airways.
The tar and mucus along the lining of the trachea keep the cilia from moving like they normally would. These are tiny hairlike objects that cover the surface of all of the airways and normally get objects out of the airways. However, they lose their mobility because of the tar and mucus gathered around them. Because the mucus can't move out of the way, the person develops the classic "smoker's cough," which the body uses to try to get the toxins and mucus out of the throat, reports Healthline.
While tracheal cancer is rare, smoking is the primary risk factor for the most frequently appearing type of tracheal tumor, squamous cell carcinoma. This cancer generally grows in the lower trachea, and as the tumor grows, it goes through the airway wall, eventually causing bleeding and ulcers inside the trachea. Symptoms include difficulty breathing, wheezing, a musical sound called stridor during inhalation, and coughing with or without blood, according to Memorial Sloan Kettering Cancer Center.