Air pollutants can be categorized as either primary or secondary. Primary pollutants such as particulate matter, carbon monoxide, hydrocarbons, sulphur dioxide, and nitrogen oxides are emitted directly into the air. Secondary pollutants like photo chemical smog and acid rain are formed when primary pollutants interact chemically in the atmosphere.

1. Air Pollutants

2. Types of Air Pollutants
Primary Secondary

3. Types of Air Pollutants
Examples
Primary : Particulate matter, Carbon monoxide,
Hydrocarbons Sulphur Dioxide, Nitrogen oxides
Secondary : Photo chemical smog, Acid rain