Zhong Nanshan, academician of China Academy of Engineering and director of Guangzhou Institute of Respiratory Diseases, once pointed out at a forum that in the past 30 years, the smoking rate of the public in China has been declining, but the prevalence of lung cancer has increased more than four times. This may be related to the increase in haze days.
Zhong Nanshan emphasized that foggy weather with very low visibility will have an impact on human health. The composition of smog is very complex, including hundreds of atmospheric particles. Among them, aerosol particles with a diameter less than 10 micron are the main hazards to human health, which can directly enter and adhere to the upper and lower respiratory tract and lung lobes of human body, causing rhinitis, bronchitis and other diseases, and can also induce lung cancer in this environment for a long time.
Besides cancer, smog is also a heart killer. Studies have shown that when pollutants in the air deteriorate, the mortality rate of patients with cardiovascular diseases will increase. Particulate pollutants on cloudy days will not only cause myocardial infarction, but also cause myocardial ischemia or injury.
When the smog is shrouded, the air pressure is low and the oxygen content in the air drops, which makes it easy to feel chest tightness. Wet and cold fog and haze can also cause cold stimulation, leading to vasospasm, blood pressure fluctuation and increased heart load. At the same time, some pathogens in smog can cause headaches and even induce diseases such as hypertension and cerebral hemorrhage. People with cardiovascular diseases, especially the elderly and infirm, should never go out in foggy days to avoid accidents.
"The heavily polluted air is low in cleanliness and contains a lot of dust, pollutants and microorganisms, which will stimulate people's respiratory tract." Professor Lin Jiangtao, an expert in respiratory medicine at China-Japan Friendship Hospital, said. Fog has a very strong adsorption force, which can adsorb a large number of toxic acids, alkalis, salts, amines, phenols, pathogenic microorganisms and other substances, and then form a very large fog core, which is easily absorbed by people. These harmful substances will stimulate sensitive parts of the human body and easily induce or aggravate some allergic diseases such as tracheitis, pharyngitis and conjunctivitis.