Q2 "It is harmless so that the Benzpyrene contained in the tar of tobacco is considered." There are those who say so. Is it true? A The risk of the healthy side about which it worries most by smoking is a lung cancer. This cancer is divided especially, is difficult to discover and is known as what also has a low rate of recovery. The greatest reason of those who decide prohibition of smoking is from the fear to a lung cancer. The ingredient which has carcinogenic in a cigarette is said that it is mostly. The typical substance is a Benzpyrene. A Benzpyrene is not the patent of only tobacco. It exists also in the burn at the time of cooking the atmosphere and food which were polluted. We will absorb a fixed quantity of a Benzpyrene only by leading everyday life. Even if nothing smokes, we cannot avoid the risk. Various contaminants to an extraordinary life are surrounding not only to a Benzpyrene but to ours. Many carcinogens exist in it. An example is the exhaust gas of a diesel car. Probably, there are also many people who looked at signs that black lead was sprinkled and thought was unpleasant from that abandonment mouth. If that gas is inhaled directly, there is likely to be a lung cancer risk of the more than which smoked some dozens of cigarettes. The carcinogen contained in the processed food is also severe. An antiseptic, a chemical seasoning, synthetic coloring matter, the oxidization prevention agent, etc. are contained so that it is called being also now. It is polluted by agricultural chemicals now until it results in vegetables, fruit, grain, and meat. Moreover, the carcinogen more than Benzpyrenes, such as trihalomethane, is contained in tap water. If such a situation is supposed, although we will suck one cigarette and 2 now and it will not inhale, there is a view which is not related in the body. It will become such reason if enclosed by the contaminant with which only this has carcinogenic. "It is the problem of fate to become cancer. If it becomes and is unavoidable, do we abandon and spread? " Moreover, it is clear that the Benzpyrene itself is a detrimental substance. But, the causal relationship of a lung cancer is not so clear as is regarded as general. A smoking person has many lung cancer persons statistically, and it only talks about the Benzpyrene as the cause. There is no direct proof that a Benzpyrene promotes development of symptoms of cancer certainly. A smoking addict also has many those who do not become cancer. Moreover, it is said that a hereditary element is also in cancer. "If a near relation person does not have a cancer patient, even if it smokes, there are few risks which become a lung cancer." It is supposed. The function to perform nonpoisonousization is in human beings' immunity organization by taking in the substance which opposes the development-of-symptoms substance of cancer. It is impossible to live, without any human beings taking in a carcinogen at all. Nevertheless, all of human beings do not show the symptoms of cancer. It is because an immunity system works effectively, development of symptoms is prevented or the cell which became cancerous is removed. The weak person of this system and those with a defect will show the symptoms of cancer. If such a matter is described, a smoking person may optimismize. But, we cannot discern in person whether it is feeble easily with strong immunity power to cancer. The person with hereditarily weak anti-cancer immunity power with many cancer patients is sane to a near relation person. But, although those who are not so have strong immunity power, they do not become precocious. There is no technology which measures immunity power with the present medicine level. There is a method of investigating the numbers of leukocytes and antibodies. But, it is not the conclusive factor except for a part of cancer whether it is effective. Moreover, an element more acquired than a native element commits immunity power strongly. It changes with a living environment or food a lot. If environment is bad, of course, the risk of cancer onset of a disease will become high. Smoking is the act in which immunity power is reduced certainly.