Environmental tobacco smoke
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Environmental tobacco smoke is made up of the smoke released by the cigarette between puffs (85%) and the smoke exhaled by the smoker (15%). The gaseous fraction is predominant (90-95%). Due to a lower combustion temperature, the smoke from burning cigarettes, known as second-hand smoke, is more toxic and more irritating than the smoke inhaled by the smoker. Tobacco smoke contains some 4,700 substances, including numerous irritants, toxicants and 43 carcinogens. Tobacco smoke is the most dangerous source of domestic air pollution, not only because of its high concentration of toxic products, but also because people are exposed to it at all ages and for much longer periods than those exposed to outdoor air pollution. The main toxicants in tobacco smoke are combustion products (leading to the formation of carcinogenic compounds such as tars), carbon monoxide (which binds to the blood's hemoglobin instead of oxygen, thus greatly reducing tissue oxygenation) and nicotine. The latter is responsible for the physical dependence on tobacco and also has an effect on the cardiovascular system (increased blood pressure, heart rate, vasoconstriction). |
updated on 4/28/24
