This is how the earth is laid!
Pollution comes from two different categories:
Gases and vapours
Most types of pollutants can be assigned to one or more categories.
Gases and vapours:
Low Ozone Level
These pollutants require activated carbon filters to absorb them.
Asbestos dust from brake linings
Black smoke from exhaust emissions
Any other material that is solid in nature
There are two types of dust:
Inhalable and Respirable
Inhalable dusts: are large enough to be trapped in the nasal hairs and mucous membranes at the back of the throat.
Respirable dusts: are particles that pass the nasal hairs and mucous membranes of the throat and enter the lungs and then the blood barrier. These dusts can carry carcinogenic substances found in petrol (benzene, pyrene, etc.) into the blood barrier.