Smoking is harmful to health, because what is the main thing in the smoke?

The smoke released by tobacco combustion contains more than 3,800 known chemical substances, most of which are harmful to human body, including alkaloids such as carbon monoxide and nicotine, amines, nitriles, drunkenness, phenols, alkanes, aldehydes, nitrogen oxides, polycyclic aromatic hydrocarbons, heterocyclic compounds, hydroxyl compounds, heavy metal elements, organic pesticides and so on. They have a wide range, and they have various biological functions and do various harm to human body. Nicotine, also known as nicotine, is a colorless and transparent oily volatile liquid with irritating smoke smell. Nicotine is the main source of addiction. It takes only 7.5 seconds to inhale nicotine from cigarette smoke to reach the brain, which makes smokers feel a mild and pleasant feeling, which can make the central nervous system excited first and then inhibited. The half-life of nicotine in plasma is 30 minutes. When nicotine is below a stable level, smokers will feel fidgety, unwell, nausea and headache, and they are eager to smoke to supplement nicotine. △ 1 Nicotine in cigarettes can kill 1 mouse. △ Nicotine in 25 grams of cigarettes can poison a cow. △ 40-60 mg of pure nicotine can poison a person. The content of nicotine in cigarettes varies with the quality of tobacco leaves and processing technology. Generally, each cigarette contains 1.5-3 mg. When smoking, about 25% of nicotine is destroyed by burning, 5% remains in cigarette butts, 50% diffuses into the space, and only 20% of nicotine is really absorbed by the human body, so some people will not be poisoned if they smoke a box of cigarettes a day. However, the stimulation and damage of nicotine to many human organs are increasing day by day. △ Nicotine can cause stomach diseases such as stomach pain; △ Nicotine can cause high blood pressure, rapid heartbeat and even arrhythmia, and induce heart disease; △ Nicotine damages bronchial mucosa and causes tracheitis; △ Nicotine poisons brain cells and can cause central nervous system symptoms of smokers; △ Nicotine can promote the formation of cancer. Carbon monoxide is a colorless and odorless gas. People often say that gas poisoning means carbon monoxide poisoning. The affinity of carbon monoxide with hemoglobin is 250 times higher than that of oxygen. When people inhale more carbon monoxide, carbon monoxide and hemoglobin combine to form a large number of carbon hemoglobin, while oxygenated hemoglobin is greatly reduced, leading to hypoxia in tissues and organs, which in turn damages many organs such as brain and heart. Each cigarette can produce 20-30 mg of carbon monoxide when burning. If many smokers gather in crowded and unventilated rooms, the concentration of carbon monoxide in the air can reach 0.05%, which is close to the concentration of gas poisoning. The hemoglobin concentration of normal people who don't smoke is about 0.5%, while that of heavy smokers is as high as 15%-20%. That is to say, 15%-20% hemoglobin loses the function of transporting oxygen, leading to hypoxia. Smoke tar is a brown viscous resin, commonly known as "smoke oil". Smoke tar contains many carcinogens. Moreover, it will adhere to the surface of the trachea, bronchi and alveoli of smokers, causing physical and chemical stimulation and damaging the respiratory function of the human body. Benzopyrene Benzopyrene is a strong carcinogen, which still exists in coal, oil and natural gas, but can be diluted by the atmosphere, while benzopyrene in cigarettes is directly inhaled or diffused indoors by smokers, with a high concentration. When burning a pack of cigarettes, 0.24-0.28 micrograms of benzopyrene can be produced. According to the survey results, every time the content of benzopyrene in the air increases, the incidence of lung cancer will increase by 5%- 1μg/ 1 000m3. Radioactive substance Cigarette smoke contains two radioactive isotopes, 2 10 aluminum and 20 1 polonium, which can be absorbed into the lungs and deposited in the body when smoking. They emit radiation continuously for a long time, damaging lung tissue. A person who smokes 20 cigarettes a day inhales the radiation of radioactive elements in one year, which is equivalent to 300 X-ray chest films taken by smokers 1 year. Irritating compounds Tobacco smoke contains a variety of irritating compounds, including hydrogen cyanide, formaldehyde, acrolein and so on. For example, 1 filter-free cigarettes can produce 45 micrograms of acrolein and 100-400 micrograms of hydrogen cyanide, which destroys bronchial mucosa and weakens the function of alveolar macrophages, making the lungs and bronchi vulnerable to infection. Harmful Metals Tobacco contains harmful metals, such as arsenic, mercury, cadmium and nickel. Taking cadmium as an example, its harm is that △ cadmium can accumulate in the body, causing asthma and emphysema. △ Trace cadmium will kill sperm in vas deferens and affect fertility. △ A large amount of cadmium enters the bone tissue, which makes the bone decalcified, deformed and brittle and prone to fracture. 1 cigarette contains cadmium 1-2 micrograms, of which 5% is absorbed by human body. Other harmful substances Tobacco also contains a variety of harmful components, such as carcinogens-dimethyl nitrosamine, methyl ethyl nitrosamine, diethyl nitrosamine, nitrospyrrolidine, hydrazine, vinyl chloride, ethyl carbamate and so on. Cancer-promoting substances-methyl ethyl phenyl alcohol, fatty acids, etc. The harmful components in tobacco smoke can be called a terrible cold-faced killer. Every smoker should be vigilant, quit smoking as soon as possible and choose health. 2. Poisons and Harms in Tobacco and Smoke According to scientists' determination, tobacco contains hundreds of complex chemical components, most of which are harmful to human body, among which 40 kinds of tar, nicotine, phenols, alcohols, acids and aldehydes are toxic and carcinogenic. After the cigarette is lit, the smoke produced contains all the chemical components in tobacco, and at the same time, it also adds some harmful substances to tobacco itself, such as carbon monoxide and cigarette tar. This is because in the process of making cigarettes, in addition to the tobacco itself, some substances such as cocoa, licorice, sugar, glycerol and ethylene glycol are added to the raw materials. Although these additives are harmless in themselves, they have changed during combustion. For example, when the back of a mouse is coated with smoke oil produced by cocoa burning, skin tumors will grow. Glycyrrhizic acid in licorice. After combustion, it can be combined with other components to generate carcinogenic polycyclic aromatic hydrocarbons. When sugar is burned with tobacco, the tar content increases, and the products of sugar combustion are important carcinogens in tobacco. After burning, substances such as glycerol and ethylene glycol may not only make smokers suffer from bladder cancer, but also produce acrolein, which inhibits the discharge of tracheal and ciliary secretions from the lungs, thus increasing the chances of suffering from tracheitis and emphysema and aggravating the conditions of people suffering from these two diseases. Nicotine in cigarettes is the most abundant and toxic, and adults can die if they ingest 50 mg. A group in France held a smoking competition. A smoking champion smoked 60 cigarettes in a row and died of poisoning before receiving the prize. Nicotine is also the chief culprit of cardiovascular diseases. Doctors report that a puff of smoke contains 4 billion dust particles and hundreds of compounds. Including dozens of toxic substances and carcinogens. Therefore, smoking in public places and indoors is extremely harmful. If one person in the family smokes, all the men, women and children in this family will suffer and become "passive smokers". Someone investigated 9 150 non-smoking women over 40 years old and found that the incidence of lung cancer in women whose husbands smoked was significantly higher than that in women whose husbands did not smoke. Inhalation of smoke not only affects children's development, but also easily suffers from diseases such as bronchitis and pneumonia. Especially in families with babies, if the father smokes indoors, harmful substances such as nicotine in the smoke can easily enter the brain, which will affect the child's brain development over time. The content of tar and nicotine in smoke is twice that of smokers, four times that of carbon monoxide, two times that of 3,4 benzopyrene and 50 times that of ammonia and nitrosamines. If the air is not circulated, the concentration will be higher. If the wife is pregnant, she often inhales the smoke from her husband's smoking, which will poison the fetus. 3. Air Pollution Caused by Cigarette Smoke People all over the world are very concerned about air pollution, because many surveys and scientific research data prove that air pollution is an important environmental factor for the growth of people's respiratory diseases and cardiovascular diseases. From the source analysis of air pollution, cigarette smoke is also an important air pollution besides industrial smoke and waste gas pollution, domestic fuel pollution such as coal burning and automobile exhaust pollution. This is not only that smokers are polluting themselves, but also that non-smokers are passively polluted by cigarette smoke. The chemical composition of cigarettes is complex, about 1 0,200 kinds. There are many kinds of harmful substances in cigarette smoke, among which more than 30 kinds are obviously harmful to human health. In cigarette smoke, there are more than a dozen polycyclic aromatic hydrocarbons with cancer risk. The content of benzopyrene in 1000 cigarettes can be as high as 122 micrograms, and domestic cigarettes are no exception. If a person smokes more than 20 unfiltered cigarettes every day, he can inhale more than 700 micrograms of benzopyrene every year. This figure is sometimes higher than the amount of benzopyrene inhaled by everyone from urban polluted air every year. Many investigation reports believe that smoking is an important reason for the increase of lung cancer in urban residents. Through population epidemiological investigation, it is estimated that the risk of lung cancer death of smokers is about 8 ~ 15 times that of non-smokers. In some occupations, such as workers exposed to asbestos and uranium mines, smokers are at greater risk of lung tumors than non-smokers. Lung cancer is related to smoking and benzopyrene pollution, which has been confirmed by many scientific research data. There are carcinogens in cigarette smoke, besides carcinogenic polycyclic aromatic hydrocarbons such as benzopyrene, there are nitrosamines and azo impurities. Three diseases that threaten human life and health: cerebrovascular disease, heart disease and cancer are all related to smoking. These three diseases are the three major causes of human death. It can be seen that it is an urgent problem to strengthen research and eliminate the environmental factors of these diseases. There are reports of acute poisoning death caused by smoking at home and abroad. In China, there are also cases where people who smoke too much get drunk and spit yellow water and die. To this end, Emperor Chongzhen once ordered a ban on smoking. It is also reported abroad that a young man in the former Soviet Union smoked 1 cigarette for the first time and died after smoking 1 cigar. A 40-year-old healthy man who has been smoking for a long time in Britain smoked 14 cigars and 40 cigarettes overnight because of a very important job. He didn't feel well in the morning and died after being rescued by the doctor. A French club held a smoking competition. The winner smoked 40 cigarettes and died before receiving the prize. Other contestants are dying and go to the hospital for rescue. So why do some people smoke a lot but not get poisoned? Many people smoke a box of cigarettes (20 cigarettes) every day, among which the nicotine content greatly exceeds the lethal dose of people, but few people die of acute poisoning. The reason is that smoking usually does not inhale all the toxic substances in cigarettes into the lungs at once. About 50% of nicotine diffuses into the air with smoke, some of which is neutralized by formaldehyde in smoke, 5% is thrown away with cigarette butts, and 25% is destroyed by burning. Smoking poisons inhaled into the body can be destroyed by about 80% after liver detoxification. In addition, most people don't smoke continuously, nicotine slowly enters the body intermittently, and long-term smoking makes the body tolerant. Therefore, although smoking heavily for a long time, acute poisoning does not occur. It is worth noting that the poison in smoke is harmful to human body gradually, and some people ignore this point. In fact, nicotine is a bait that leads people to the grave. The real killer is the synergistic effect of carbon monoxide in smoke and various toxic substances, which is the cause of disease death. The general rule is that the higher the smoking index, the greater the harm.