History

• Although the cancer-causing effects of cigarette smoke started to become known as early as the 1940s and '50s, cigarette companies engaged in an infamous marketing campaign that both denied these findings and tied smoking to images of glamor and success. "Big Tobacco" has since earned one of the worst reputations of any industry. But tobacco companies did actually attempt to develop "safer" cigarettes through the 1960s and 1970s--only to balk at the legal challenges inherent in introducing a safe' version of a product already advertised as safe. In the 1990s, a series of lawsuits asked the tobacco industry to pay for the damages incurred by their products. The next decade saw a groundswell of public opposition against cigarette smoke, with an increasing number of cities and even whole countries enacting smoking bans.
  
  

Function

• Inhaling cigarette smoke provides for the near-immediate absorption of chemicals into the body. An average cigarette contains anywhere from one to two milligrams of nicotine, an addictive stimulant which travels from the lungs to the brain in as little as seven seconds. The effects of cigarette smoke can vary, however, depending on how it is inhaled. Quick puffs of smoke provide a stimulating effect, whereas deeper puffs can induce a sense of relaxation.
  
  

Types

• Smoking a cigarette results in two types of smoke: side-stream smoke, produced by the cigarette's burning end, and mainstream smoke, inhales by the smoker. Second-hand smoke (also known as environmental smoke, or passive smoke) results from the combination of mainstream and side-stream smoke. And in January 1993, the Environmental Protection Agency (EPA) deemed secondhand smoke to be a "human lung carcinogen" in its own right.
  
  

Effects

• Cigarette smoke is a veritable smorgasbord of chemical agents: of the 4,000 substances that have been identified, dozens are classified as carcinogenic. These agents have a range of effects. For example, the carbon monoxide found in cigarette smoke can bind to hemoglobin, thereby preventing red blood cells from transmitting a full load of oxygen. Chronic exposure to cigarette smoke can promote atherosclerosis, advance the aging process, and reduce the body's ability to repair damaged cells.
  
  

Significance

• Smoking-related illnesses result in hundreds of thousands of deaths each year, and hundreds of billions of dollars in lost productivity. Cigarette smoke stands as the leading cause of cancer in men and women alike, in not only the lungs but also the larynx, esophagus, and even bladder. And each year in the United States alone, secondhand smoke is blamed for the deaths of 3,000 non-smokers, and 300,000 lower respiratory tract infections in children eighteen months old or younger. Despite the health impacts, however, global smoking rates have continued to rise. Estimates suggest that a billion people smoke worldwide, particularly in the developing world.