Cigarette smoking affects the respiratory system in smokers through direct inhalation of gas and particulate from burning plant matter. The carcinogenic chemicals in cigarettes, such as nicotine and benzo[a]pyrene, can contaminate smokers' personal environments, where anyone can come into contact with them. Secondhand smoke itself also puts nonsmokers at risk for some related health problems, including cancer and obstructive diseases. The American Lung Association notes that these widespread risks have prompted new laws in many jurisdictions that restrict smoking in public areas.
Pneumonia
The Environmental Protection Agency or EPA reports that cigarette smoking and airborne particulate damage lung tissue. This makes people affected by tobacco smoke more prone to respiratory system illnesses in general and complications from infections such as pneumonia in particular.
Asthma
Respiratory systems that are already compromised by asthma may experience increasing symptoms under the effects of cigarette smoking and secondhand smoke, according to the EPA. The U.S. Department of Health and Human Services notes that children exposed to nicotine from secondhand smoke may have a higher risk for developing asthma.
Chronic Bronchitis
The American Lung Association or ALA reports that chronic bronchitis is one of two forms of chronic obstructive pulmonary disease or COPD, caused by cigarette smoking. Health problems associated with bronchitis include breathing obstruction resulting from excess mucus, which forms in an attempt to address toxic buildup.
Because the cilia of the bronchial airways no longer function properly, a chronic "smoker's cough" arises to clear this mucus from the bronchi. This may be ineffective amidst persistent inflammation, resulting in internal scarring and chronic shortness of breath.
Emphysema
Emphysema is the other form of COPD caused by tobacco smoking. Its extreme effects on oxygen exchange in the respiratory system can be fatal, and in fact, it is the fourth major cause of death in the United States, as the ALA notes.
Emphysema is a degenerative lung disease that causes holes in lung tissue, destroying the air sacs, or alveoli, and severely decreasing breathing ability and exercise tolerance. The ALA also points out that these health problems can increase the risk of heart failure.
Cancer
Lung cancer is the most common form of respiratory cancer contracted by smokers and nonsmokers as a result of contact with tobacco smoke. The American Cancer Society reports that lung cancer is the hardest cancer to treat, resulting in 90,000 total U.S. fatalities per year.
The Centers for Disease Control and Prevention reports that smoking accounts for 85 percent of all U.S. lung cancer deaths. Other health problems created by the carcinogenic chemicals in cigarettes include cancers of the mouth, lips, tongue, larynx and throat.
