There are natural factors (such as forest fires and volcanic eruptions). ) and human factors (such as industrial waste gas, domestic coal burning, automobile exhaust, etc. ), and the latter is the main factor, especially caused by industrial production and transportation. The main process consists of three links: pollution source discharge, atmospheric transmission and human suffering.
Extended data:
Air pollutants refer to substances discharged into the atmosphere due to human activities or natural processes, which have harmful effects on the environment or people. Air pollutants can be divided into two categories according to their existing state:
One is aerosol pollutants, and the other is gaseous pollutants; It can be divided into primary pollutants and secondary pollutants according to the formation process. Main pollutants refer to pollutants directly discharged by pollution sources.
Secondary pollutants are new pollutants whose physical and chemical properties are completely different from those of primary pollutants through chemical or photochemical reactions, and their toxicity is stronger than that of primary pollutants.
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