Tobacco

Tobacco is a tall, leafy annual plant, originally grown in South and Central America, but now cultivated throughout the world, including southern Ontario. There are many species of tobacco; Nicotiana tabacum, or common tobacco, is used to produce cigarettes.

About 90% of the content of cigarettes is plant matter. The remaining 10% is a combination of chemicals and other additives. Nicotine is a powerful central nervous system stimulant found naturally in the tobacco leaf. It is classified as a drug. In higher doses, nicotine is extremely poisonous. It is commonly used as an insecticide.

Tobacco leaves can be burned and inhaled (in the form of cigarettes, cigars, pipes, smoke, etc.) or absorbed through the mouth in the form of spit tobacco, chew, or snuff. The membranes in the nose, mouth and lungs act as nicotine delivery systems - transmitting nicotine into the blood and to the brain. Smokers usually feel dizzy and sick when they first inhale the nicotine in tobacco, but gradually build up tolerance to its effects.

Nicotine is highly addictive. Stopping use can produce unpleasant withdrawal symptoms including depression, irritability, anxiety, and craving for nicotine.

Manufacturers also add compounds like ammonia to cigarettes. These compounds are commonly referred to as additives, or flavourings.

"Tar" - a short name for the solid particles found in tobacco smoke - is made up of the natural by-product of burning tobacco and chemical additives. Cigarette smoke contains about 4,000 known poisons and cancer-causing substances, including cyanide, benzene, vinyl chloride, and formaldehyde.

Tobacco may be a natural substance - but it is anything but harmless. When used exactly as intended by manufacturers, tobacco kills.