Cigarette smoke contains over 4000 chemicals including well characterized toxicants and carcinogens (EPA, 1992). These chemicals stimulated affect on developing tissue and organisms (Melkonian, 2003). Many studies showed that smoking is an important risk factor for cancer, especially lung cancer and other diseases (Tominaga, 1988). Cigarette smoking
has caused of about 85% of the deaths due to lung cancer, and more than 40% of smokers have been dead in terms of smoking related-diseases (AIM, 1986).
In the U.S there has been a steeper rise of the people who got the lung cancer from smoking. Since 1950 percentage of all cigarettes filter cigarettes sold increased from 0.56 to 92% in 1980 and to 97% in 1990 (Blizzard, 2002). For lung cancer it was observed that non-filter smoker had more risk than filter smoker. The incidence of lung cancer of non-filter smoker was more than 50% higher than that of filter cigarette smokers (Rimington, 1981). So some reduction in lung cancer rates might be expected, because risk of lung cancer was reduced for smokers who switched to filter cigarettes. But recently many studies have not produced consistent results, and many people with the highest-age adjusted rates of cancer smoke filtered cigarettes (Blizzard, 2002).