Dust, smoke and air pollution
The emission of dust and soot directly leads to the increase of the content of suspended particulate matter in the atmosphere. Generally, atmospheric particles, also known as floating dust, are solid or liquid particles in the atmospheric environment.
According to the causes, it can be divided into primary particles and secondary particles. The air pollutants caused by road dust, construction dust, industrial dust and kitchen smoke and some air pollutants existing naturally are collectively referred to as primary particles. The air pollutants formed by the continuous chemical reaction between particles and other air pollutants in the environment are secondary particles.
At present, sulfate particles, nitrate particles and photochemical smog have had a serious impact on the environment. The components of these secondary particles are very complex. Because they are porous, they can adsorb small molecular substances in the environment. If the adsorbed substances contain heavy metal elements such as lead, chromium and arsenic, they will cause serious harm to human respiratory system and gastrointestinal system.
Particles larger than 10 microns in diameter cannot pass through the nose and throat, stay in cilia and mucus, and are finally discharged from the body; PM10 can pass through the first barrier of the human body to the bronchus and alveoli, PM2 It has stronger penetration, can reach the bronchial wall and affect the gas exchange in the lung, causing damage to the human respiratory system and cardiovascular system, causing cough, asthma, dyspnea, pulmonary failure, chronic bronchial disease and even heart disease.
Because particles also contain carcinogens such as polycyclic aromatic hydrocarbons and benzene, the risk of human cancer increases. The heavy metals in the particles that breathe into the human body are gradually enriched in the human body, and finally endanger the health of human organs.
2. Sulfur dioxide air pollution
The sulfur dioxide discharged into the atmosphere forms sulfuric acid mist and sulfate aerosol through complex physical changes. These are important substances that cause acidification of the environment, which are also important components that cause acid rain.
Relevant studies have shown that when the concentration of sulfur dioxide in the atmosphere reaches 0.5mg/L, it begins to affect the human body. When the concentration reaches 1-3mg/L, people can obviously feel irritation. When the concentration reaches 400-500mg/L, the human respiratory tract will appear. Ulcers and lung edema can even lead to death. At the same time, because sulfur dioxide and the smoke and dust in the environment can have a synergistic effect, when the concentration of environmental air pollutants is low, it can have an adverse effect on people, increase the incidence of respiratory diseases, and aggravate the condition of patients with chronic respiratory diseases.
After entering the respiratory tract, sulfur dioxide will be blocked and absorbed by the mucous membrane in the respiratory tract, forming sulfurous acid, sulfuric acid or sulfate, thereby irritating the respiratory tract. In addition, sulfur dioxide also has a cancer-promoting effect, which can strengthen the carcinogenic effect of benzo(a)pyrene. Sulfur dioxide also has the effect of causing vitamin C metabolism disorders and affecting the body's enzyme activity, causing the growth and development of the body to be affected.
