When smoking most of the nicotine escapes in the air while a fifth of it gets into the lungs. Smoking a pipe produces slightly more nicotine than smoking a cigar. The stronger the fire of the burning surface the more nicotine to gets into the system. Therefore the more rapidly you smoke the more nicotine you breathe, the shorter the stub gets, the greater the amount of nicotine you inhale.
Pure nicotine is a very powerful poison. A drop of it on the skin of a rabbit causes an immediate shock. If you smoke a packet of 20 cigarettes every day you inhale 400 mg of nicotine more or less per week. If this quantity was injected instantly it would kill you like a gunshot.
In the respiratory tract there are various substances that cause health damage, irritating substances like hydro cyanic acid, acrolein, formaldehyde and ammonia. Our respiratory system is provided with a "cleaning system" made up of many cells acting as a barrier for dust, germs and toxic substances, which it uses when we inhale. But irritating substances contained in smoke can easily damage this "cleaning system" and make it easier for damaging substances to get into the lungs. By smoking you are not just damaging your lungs but also increasing your exposure to smog and other polluting agents that are no longer blocked through the cleaning system.
The typical smoker's cough and catarrh is a sign and lack of efficiency of the lung cleaning system, which causes an excess of mucus, chronic bronchitis and emphysema. Among the substances deposited inside the lung many increase the risk of lung cancer, which in 85-90% of cases is caused by cigarette smoke. Smoking causes other types of cancer along the respiratory tract also, especially in the oral cavity, in the pharynx and in the larynx, circulatory system and heart.
The substances that damage the circulatory system are basically CARBON OXIDE and NICOTINE. Carbon oxide reduces the quantity of oxygen available for the entire system; heart, brain, muscles, etc. Together with nicotine, carbon oxide speeds up the formation of arteriosclerosis patches in blood vessels thus increasing the risk of MYOCARDIUM INFARCTION and STROKE.
Other damage occurs also such as; risks of cancer affecting numerous other organs apart from the lungs and the respiratory tract, bladder, esophagus, kidney, pancreas, neck and body of the uterus, hair loss, bad breathe, spots on skin and teeth, damaged skin etc.
Smoking reduces athletic performance remarkably. Today all professional athletes are non-smokers.