Teaching Exercise 3.2: Air Pollution & Respiratory System The photos shows an used air filter from a home air filter that has been opened so that it is possible to see the effects of air pollution on the filter. The whiter areas are spots that did not come into contact with the air and are free of air pollutants.  Respiratory (Lung) and Air Pollution The lungs are exposed to the same levels of pollution that the air filter is exposed to. We are constantly breathing in a combination of natural pollutants, such as dust and pollen, and man-made pollutants, such as fine particles from the breakdown of material in residential homes. Areas in the country where there are higher levels of air pollution have higher levels of lung disorders.   Steam Inhalation Therapy - 3 Effects 1. Increase in moisture in the entire respiratory system as the steam condenses from vapor to liquid. 2. Has a temporary heating effect on the respiratory system which increases the metabolic activity of the cells. 3. Products can be added to the steam being  inhaled that are known to have a therapeutic effect on the system.