The Surgeon General's report of 1982 states that cigarette smoking is the single major cause of cancer death and that one in five of all deaths are the result of tobacco use. It is not difficult to understand why these statements are true when you understand what is contained in tobacco smoke. According to Help with Smoking.com, tobacco smoke contains over 4,000 chemicals that are inhaled into the body, more than 60 of which are known to cause cancer. The Environmental Protection Agency has classified tobacco smoke as a Class A carcinogen, meaning that it is well understood that it causes cancer in humans.
Nicotine
Nicotine is one of the chemicals found in cigarette smoke that is responsible for many of the immediate physiological effects that smoking has on the body. It is a stimulant in humans and causes alertness, sharpness, reduced appetite and raised metabolism. Nicotine also damages the cells that line the blood vessels, and according to the American Heart Association, smokers have two to four times the risk of developing coronary artery disease than non-smokers do. Nicotine acts on receptors in the brain and is the substance in cigarette smoke that makes it highly addictive. Many smokers find their dependence on nicotine a very difficult thing to break.
Tar
Tar is a term for all of the particulate matter found in cigarette smoke. It is deposited mainly in the lungs, causing damage to the cilia of the airways that are responsible for blocking and removing debris from the lungs. Since tar actually remains in the body, it can clog lung air passages and lead to diseases that make it difficult to breathe, such as emphysema and chronic bronchitis. The body recognizes tar as a foreign substance and sets off an immune response that leads to mucous production. Tar is a known carcinogen and is responsible for much of the lung cancer caused by smoking. According to the National Cancer Institute, lung cancer is the leading cause of all cancer death in the United States.
Carbon Monoxide
Smoke from cigarettes produces a byproduct called carbon monoxide. This gas has a greater affinity for hemoglobin in the blood than does oxygen, causing the blood to become saturated with carbon monoxide and reducing its ability to deliver oxygen to the body. According to Physicians for a Smoke-Free Canada, carbon monoxide causes impaired motor function, headaches, decreased heart function, decreased exercise tolerance and reproductive damage.
Other
Among the many other substances found in cigarette smoke are formaldehyde, which is also used to embalm bodies, arsenic, which is a deadly poison, acetone, which is used to remove nail polish, ammonia, found in many cleaning products, and benzene, which is a solvent in fuel. There are many other chemicals found in smoke, and many are cancer causing.
