The effects of smoking on the respiratory system include acute infections and chronic diseases. These conditions aren't limited to tobacco users, but extend to people who breathe their secondhand smoke. For this reason, many employers and managers of public buildings have restricted cigarette smoking to outdoor areas.
Even outdoor airborne smoke is harmful, however, especially to individuals with already weakened respiratory systems. The cumulative effects of tobacco smoke on the human body, and the lungs in particular, can create potentially fatal medical conditions.
Acute Respiratory Symptoms
Young smokers, developing children and tobacco users themselves experience short-term respiratory irritation after inhaling first- or second-hand smoke. The Centers for Disease Control and Prevention (CDC) note that smokers and children who inhale smoke get infectious bronchitis more frequently than is normal. These symptoms include coughing, wheezing, phlegm and shortness of breath, and they may become chronic.
Severe Asthma and Allergy Attacks
Children and those with compromised respiratory systems are at risk for heightened symptoms from existing conditions. The U.S. Surgeon General's 2006 report on second-hand smoke relates that asthma and allergy attacks are exacerbated by contact with smoke. Severe asthma reactions suppress breathing ability and can be fatal.
Pneumonia
In 2004, the surgeon general's office added pneumonia to the list of lung diseases caused by cigarette smoking. Again, children who are exposed to secondhand smoke are vulnerable, as are teenage and adult tobacco users. The CDC notes that the risk is raised when damage from smoke affects the immune system, allowing lung infection to take hold.
Chronic Bronchitis
Chronic bronchitis is a type of chronic obstructive pulmonary disease (COPD) that typically affects smokers in a relatively short time in the course of their habits. Cigarette smoking damages the airways, producing a "smoker's cough" to dislodge the excess mucus that accumulates in the lungs and bronchi. According to the American Lung Association, this condition weakens the lungs and invites bacterial infection. It also eventually scars the bronchi, making more serious breathing obstructions likely.
Emphysema
Emphysema is a form of COPD associated with long-term tobacco use. The American Lung Association reports that, in this stage, the tissue damage from early-stage bronchitis compounds, causing collapse in the walls of the lung air sacs. These holes in lung tissue are irreversible and severely degrade breathing ability as less and less oxygen is transferred to the blood and to the rest of the body's cells.
Respiratory System Cancers
Smokers and adults and those who breathe secondhand smoke risk carcinogenesis from the compounds in tobacco smoke. Lung cancer affects both groups, according to the CDC. Cigarette smoking may also cause mouth, throat and larynx cancers in those who ingest it firsthand.
