|MadSci Network: Medicine|
The issue is not so much "what cigarettes are made of", but "what do cigarettes turn into when you burn them". You can extract cancer-causing chemicals from tobacco, but the real problem comes from what tobacco turns into when it is burned.
Although I cannot find any specific information, I suspect that if you burned any kind of plant material and inhaled the smoke over a long period of time you would risk getting lung cancer. On the other hand, firefighters, who are exposed to smoke on a regular basis, do not have a dramatically increased risk of lung cancer.
When cigarette smoke is analyzed, thousands of chemicals can be identified, many of which are known mutagens and/or carcinogens. The list includes:
The best source of information on smoking and cancer is probably the 1982 report on "Smoking and Health" from the US Surgeon General's Office.
Medical College of Wisconsin
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