Tar, nicotine, carbon monoxide, as well as formadehyde, hydrogen cyanide and benzene, are all present in tobacco smoke. In many countries, tar and nicotine measurements are printed on cigarette packages and in several parts of the world, these components have regulated limits.
What is tar?
Cigarette smoke contains tiny particles that can be collected on a filter pad in a laboratory when a cigarette is smoked by a machine. Tar is usually defined as the weight of particulate matter collected in this way, after water and nicotine are subtracted. Tar is a complex mixture that includes substances which, in sufficient quantities, are thought capable of initiating and promoting cancer.
What is nicotine?
Nicotine occurs naturally in the tobacco plant and is a constituent of tobacco smoke. It is also found in other plants, but at much lower levels than in tobacco. Nicotine has unusual pharmacological properties; it has both a mild stimulant effect, though less than that of caffeine, and a mild relaxing effect. At high levels – far higher than in cigarette smoke – nicotine is toxic. Many public health authorities believe nicotine is responsible for causing addiction to smoking through its pharmacological effects.
What is carbon monoxide?
Carbon monoxide is a gas formed when plant materials burn. It can combine with haemoglobin in blood, reducing the blood’s capacity to carry oxygen. Health Canada, and other public health authorities, state that carbon monoxide in tobacco smoke is thought to be associated with the increased risk of heart disease from smoking.