The Center for Disease Control and Prevention has cited smoking as the major cause of lung cancer, chronic bronchitis and emphysema, with "cigarette smoking being the number one preventable cause of death in the United States." Smoking also causes oral and esophageal cancer and contributes to heart disease and stroke. However, more than the dismal statistics is the suffering and decreased quality of life that smokers face because of the nature of these progressive diseases.
Significance
Tobacco smoke kills epithelial cells that clear debris from the lungs. Chemicals in cigarette smoke paralyze the hair-like projections called cilia that line and protect the airways. Smoking also alters lung enzyme activity, destroying air sacs in the lungs, which leads to emphysema. Emphysema damages the alveoli, ultimately merging to form fewer and larger air sacs. This process causes a decrease in the lung's surface area and less efficient transfer of oxygen and carbon dioxide in the bloodstream. Emphysema is usually the result of cigarette smoking, and the damage is irreversible.
Diminishing Function
Nicotine diminishes the lung's capacity to exchange oxygen and carbon dioxide, the major function of respiration. It is also the substance in tobacco smoke that makes smoking addictive. Although nicotine is less damaging than other poisons in cigarette smoke, according to the National Heart Lung and Blood Institute, this substance is a co-carcinogen--meaning that nicotine works in combination with other substances in cigarette smoke to cause cancer.
Tar is the sticky brown residue that forms when tobacco burns. It consists of hundreds of different chemicals, primarily hydrocarbons. This sticky substance clogs the tiny air sacs called alveoli making oxygen exchange difficult, as well as causing an inflammatory response. Hydrocarbons can cause gene mutations and are potent carcinogens. According to the Centers for Disease Control and Prevention, research has shown that tar is a direct cause of lung cancer
Chemical Identification
Other chemicals in tobacco smoke include arsenic, ammonia, formaldehyde, lead, benzene and vinyl chloride to name a few. These poisons stimulate excessive mucus production that clogs the alveoli and small and large airways. This obstruction makes the smoker cough and causes inflammation and bronchitis, as well as numerous other lung disorders.
Side Effects
Research conducted by the Centers for Disease Control and Prevention has shown that the side-effects from second-hand smoke, or inhaling other people's smoke proves a serious health hazard. Smoke emitted from the burning end of a cigarette contains higher concentrations of toxins, such as nicotine and cancer-causing nitrosamines, than the smoke inhaled through a cigarette by the smoker. According to the Centers for Disease Control and Prevention, the Surgeon General has determined, "There is no risk-free level of exposure to secondhand smoke: even small amounts of secondhand smoke exposure can be harmful to people's health."
Misconceptions
Misconceptions abound that if a person smokes either a cigar or pipe that they become immune from the side-effects of smoking. According to the Centers for Disease Control and Prevention, the only difference between cigar and pipe smokers and a cigarette smoker is that usually these individuals inhale less smoke making their overall death rates much lower. However, all smokers remain at equal risk of death from cancers of the mouth, larynx and esophagus. According to the National Heart Lung and Blood Institute, "the smoke from cigars and pipes contain the same harmful chemicals as the smoke from cigarettes." Individuals who smoke a pipe or cigar also have an increased risk of heart disease.
References
- Centers for Disease Control and Prevention: Adult Cigarette Smoking in the United States: Current Estimate (2007)
- Centers for Disease Control and Prevention: Highlights: Smoking Among Adults in the United States: Respiratory Health
- U.S. Department of Health and Human Services: The Health Consequences of Involuntary Exposure to Tobacco Smoke
- National Heart, Lung and Blood Institute: Smoking and Your Heart
- Centers for Disease Control and Prevention: Smoking and Tobacco Use
