The method of analyzing tar substances is to use a smoking machine that simulates human smoking according to national standards. Inhale once, 2 seconds, once every minute, 35ml each time. Smoke passes through a glass fiber filter to intercept particles, and the total particles (wet tar) obtained by subtracting water and nicotine from the smoke are dry tar (that is, tar contained in cigarettes). This tar contains 20% carcinogens and 0.4% carcinogens. Therefore, the higher the tar content, the greater the harm to human body.
The conclusions are as follows: (1) It is best not to smoke; (2) If you must smoke, don't poison others; (3) Don't smoke in public places; (4) Pay special attention to tar content when purchasing cigarettes, and choose cigarettes with tar content below 15mg.
There are more than 4000 substances in tobacco, one of which is called tar, which actually contains five or six compounds. Generally, those below 7 mg are called low tar, 7- 15 mg are medium tar, and those above 15 mg are high tar. From July 2005 1, China can no longer sell cigarettes with tar content above 15 mg. At first, a China scholar found that coating tar on rabbit ears could induce cancer. According to the conclusion of our laboratory, it is inferred that the tar in cigarettes may cause lung cancer, so the concept of reducing tar and harm is put forward, which reduces the tar content of cigarettes by 60%.
It is generally believed that if you can't quit smoking, you can smoke low tar, which is not so harmful to your health.
However, tar is reduced, and nicotine in cigarettes is also decreasing. Nicotine is an addictive substance that won't make smokers lose their pleasure. Maybe they smoke more. In addition, people who smoke low tar think smoking is a safe cigarette, and it is more difficult to quit smoking.
In fact, there are many carcinogens in cigarettes. According to the precancerous substances extracted from smokers' urine, the levels of high tar, medium tar and low tar in smoking are the same, so the carcinogenicity has not decreased. Several large population studies have found that the cancer risk of low tar smokers has not decreased.
Studies have shown that smoking cigarettes with low tar content will not reduce the risk of lung cancer, and there is no significant difference in the proportion of people who smoke cigarettes with medium tar content and those who smoke cigarettes with low tar content who die of lung cancer. The propaganda of tobacco companies about reducing the harm of low tar tobacco is unfounded, unscientific and irresponsible. For smokers, the best way to protect health and prevent lung cancer is to stay away from tobacco.
Why can't the reduction of tar content in tobacco reduce the harm of tobacco? Because tobacco companies don't tell smokers the correct posture to hold cigarettes, smokers are actually still affected by nicotine and tar. Besides tar, there are many other carcinogens in tobacco.
The increase of smokers' smoking and the incorrect posture of smokers are the main reasons that lead to the harm of low tar cigarettes. The so-called low tar content is usually achieved through the side holes in the cigarette filter. Only when the side holes are unblocked can the tar content in diluted tobacco be guaranteed. However, when smokers smoke, the side hole is often covered by fingers or lips, and the protective effect of the side hole on the filter tip is lost. Therefore, for most smokers, the tar content of inhaled tobacco has not actually decreased.
In addition, as smokers switch to low-tar tobacco, the increase in the number of cigarettes and the deepening of smoking intensity are also important reasons why low-tar tobacco is harmful to health. When smokers choose low-tar cigarettes instead of ordinary cigarettes, they tend to smoke deeper with each puff, thus inhaling more nicotine and harmful substances in tobacco.
Tobacco companies attract many smokers under the banner of low tar cigarettes. According to the data, 60% smokers believe that low-tar cigarettes are harmless to health, and 50% smokers believe that low-tar cigarettes can help them quit smoking faster. From a global perspective, the output of low tar tobacco has been on the rise since the 1930s and 1940s, which is not only the success of the marketing strategy of tobacco companies, but also the dead corner of tobacco health promotion.