The main pollutants that pollute the air

Nowadays, the global air pollution problem is attracting more and more attention from human beings. Outdoor air pollutants are mainly composed of nitrogen oxides, dust, inhalable particulate matter, carbon monoxide, etc. Indoor air pollutants are mainly composed of formaldehyde, kitchen fumes, and smoke from burning tobacco. Air pollution, also known as atmospheric pollution, has become an invisible killer that endangers human health. We should actively protect the earth's air environment, drive less when going out, and eat barbecue less often.

1. Suspended particulate matter

Suspended particulate matter refers to particles with a diameter of less than 100 microns that are suspended in the air. It mainly comes from burning coal and dust on the ground. Dust with a diameter of 0.5-5 microns can directly enter the human lungs, deposit in the alveoli, and may enter the blood and be transported throughout the body. It accumulates in various parts of the body and can cause disease over time. Suspended dust often adsorbs harmful substances such as lead, cadmium, pesticides, and benzopiperidin, which can cause disease and endanger human health. The burning of coal in power plants and sandstorms are its main sources.

2. Carbon Monoxide

Carbon monoxide is a colorless, odorless, toxic gas. If there is a lot of carbon monoxide in the air, exceeding a certain concentration, it will cause a decline in consciousness, reduced central nervous system function, weakened heart and lung respiratory function, and even cause death over time. The main sources are chemical companies, incomplete combustion of coal, etc.

3. Sulfur dioxide

Sulfur dioxide is a common and important air pollutant. It is a colorless and irritating gas. Sulfur dioxide mainly comes from the combustion of sulfur-containing fuels (such as coal and oil); the smelting of sulfur-containing ores (especially non-ferrous metal ores with high sulfur content); and the production processes of chemical industries, oil refineries and sulfuric acid plants. Sulfur dioxide is a colorless but irritating gas. People can often smell sulfur dioxide in the air. It mainly comes from pollutants such as coal burning, especially when air convection is weak or there is an atmospheric inversion. When people inhale excessive amounts, it mainly causes respiratory diseases and is corrosive, which is extremely harmful to human health. In summer, it is the main substance causing acid rain, which is a harmful substance that endangers health and crops. Sulfur-containing chemical industry and the combustion of coal are its main sources.

4. Nitrogen oxides

Nitrogen oxides refer to NO and NO2 in the air. NO is a colorless, non-irritating, inactive gas that can be oxidized to NO2. NO2 is a brown gas that strongly irritates people's respiratory organs and can easily cause acute asthma. Nitrogen oxides mainly come from coal burning and automobile exhaust emissions. NO2 and hydrocarbons can generate secondary pollutants (photochemical smog) under sunlight, which will cause greater harm to human health. Among nitrogen oxides, nitrogen dioxide is the most toxic, 4-5 times more toxic than nitric oxide. Nitrogen oxides in the atmosphere mainly come from automobile exhaust and exhaust from the combustion of coal and oil.

5. Volatile organic compounds VOCs (such as benzene, hydrocarbons, formaldehyde), photochemical oxides (such as ozone O3)

6. Greenhouse gases (such as carbon dioxide, methane, and chlorofluorocarbons).