None of them. Epidemiological studies have SUGGESTED that tobacco MAY increase the RISK of developing cancer. Barbaric laboratory experiments on rats and dogs (try Googling "beagles smoking") have provided some further supporting EVIDENCE (and also contradictory evidence). Wouldn't the billions wasted be better spent researching a cure for cancer? Smoking rates are decreasing yet the incidence of cancer is increasing.
Tobacco.
The maiN ingredient is Tobacco .. Cigarettes contain over 4000 chemicals ....
Tobacco
You don't, the properties in tobacco, when steeped in an infusion, will make you sick to your stomach. Tobacco "tea" (an infusion made by steeping tobacco in water) is a main ingredient in natural or "green" insecticides.
The major ingredient in tobacco that gets you addicted is nicotine.
carcinogen
Formaldehyde is a chemical found in tobacco smoke and is also used in mortuaries. Formaldehyde is known to be a known carcinogen.
carcinogen is the main one.
Hops are used as an ingredient in perfume and occasionally as a tobacco or food flavoring. Their main food use and commercial value is in beer.
It is believed that Styrofoam can be hazardous to peoples' health. The main ingredient, styrene, is a carcinogen. Individuals should avoid drinks or food that have come in contact with heated Styrofoam, because the styrene leaks out of it when it is microwaved.
nicotine
Yes, tar is a known carcinogen. It is produced when tobacco is burned and is a major component of cigarette smoke. Prolonged exposure to tar can increase the risk of developing various types of cancers, particularly lung cancer.