First, the health effects of secondhand smoke.
1, chemical composition of environmental smog?
Compared with the mainstream smoke formed by anoxic pyrolysis, it contains more combustion products. Carbon monoxide and sidestream smoke are five times as much as mainstream smoke, tar and nicotine are three times, benzopyrene is four times and nitrosamine is 50 times. ?
2. Secondhand smoke and lung cancer?
The excess risk of lung cancer when non-smokers marry smokers is 24%(95%C 1= 13%, 36%). After adjusting for the potential bias and confounding factors caused by diet, this estimate remains unchanged. Secondhand smoke is one of the causes of lung cancer.
3. Secondhand smoke and coronary heart disease
Coronary heart disease is the leading cause of death in the United States and other industrialized countries. In many developing countries, deaths caused by coronary heart disease have increased rapidly and become the primary cause of death. Active smoking is one of the most important and clear risk factors of coronary heart disease. ?
4. Secondhand smoke and childhood diseases
At present, it is generally believed that the harm mainly includes the following aspects: (it can cause bronchitis and pneumonia. In childhood, lower respiratory tract infection or other diseases caused by secondhand smoke can further develop into asthma, aggravating the severity of existing asthma. There is causal relationship between children's exposure to secondhand smoke and middle ear diseases.
5. Other health effects?
For healthy adult non-smokers, secondhand smoke can also cause respiratory symptoms, such as cough, secretions and decreased lung function. In addition, in addition to direct health hazards, most non-smokers will feel uncomfortable because of exposure to second-hand smoke.