Bodily Defenses Image Map


 Air Pollution

Everyday hundreds of toxic chemicals are released into the environment.  Many of these chemicals are hazardous to our health and cause adverse reactions. Our body has some defense against these pollutants, but it is important to remember that we should do our best to avoid them.  Let's find out why.

What is air pollution?

  • Air pollution is a general term for a substance that contaminates the environment.  For example, the exhaust emitted from cars contaminates the environment because it releases excessive amounts of ozone, carbon monoxide, nitrogen oxides, and lead.  
  • Pollution can come from gases, particles, or liquids.  Many times, these pollutants are man-made, but sometimes they can come from the environment.  For example, pollen which is released by trees and plants, can become very abundant in the air we breathe and irritate those people who are allergic. 

Why is air pollution so bad for your lungs?
Humans are a collection of organ systems all working together to keep the body in good working order.  The body must maintain a balanced environment for the organ systems to function properly.  When the body is exposed to pollutants, this balance can be disturbed.  For example, when carbon monoxide, a deadly gas found in cigarette smoke and automobile exhaust, is inhaled into the lungs, it interferes with the bloods ability to take up oxygen.  Click here to see how.  

  • Some natural pollutants like pollen, ragweed, and molds trigger allergies in the body.  Hay fever is a condition characterized by allergic reactions to these natural pollutants.  
  • As the body is exposed to allergens, or allergy-causing substances, it begins to build up a defense.  Once the body builds up a defense against a substance, it will release defensive substances like histamine to help protect the natural balance the body needs.
  • The release of histamine and other defensive substances can trigger itching, sneezing, tissue swelling, and sinus problems.  While these may not be deadly, they are often inconvenient and can aggravate other conditions that may be present, like asthma.  
  • Asthma is a condition where allergens like pollen, dust, or other kinds of pollution can cause the airways to become more narrow, and reduce airflow to the blood vessels in the lungs where gas exchange is taking place.


How can air pollution be prevented?

  • Air pollution cannot be prevented, but it can be reduced.  Air pollution comes from many sources, some natural and others are man-made.  
  • Automobile pollution is the largest contributor to air pollution in the United States.  This can be reduced by increasing the use of public transportation systems, car pools, and reducing the amount of pollution vehicles cause.
  • Recycling is also a great way of helping reduce pollution.  Recycling means that the factories which make goods for us, do not have to make as many products for us, and do not create as much waste which can pollute our environment.  

Where is air pollution found the most?

  • Pollution is generally highest in large cities and industrial centers.  

  • Pollution from natural sources like pollen from trees is a problem in the eastern and Midwestern United States. 

  • Ragweed, which is the most common cause of hay fever, is found in most parts of the United States.

Pollution can also be an indoor problem.  Some allergens like dust or cat and dog hair can build up inside homes and work places and cause extreme discomfort for individuals that are allergic to them. Another source of indoor pollution occurs from chemicals in new or remodeled buildings.

  • "Sick building syndrome" is a result of the build up of chemicals that are continuously released from new furniture, fabrics, detergents, paints, building materials.

  • "Sick building syndrome" is increasing in prevalence because buildings are becoming more efficient at heating and cooling the air in a building, by not circulating clean air from the outside into the building.

  • As chemicals build up in a building they can reach toxic levels and cause illness.

  • "Sick building syndrome" can be avoided by maintaining a clean environment with adequate circulation of air from the outside.   It is also important to store hazardous chemicals properly.  Buildings should also be inspected to make sure that the building materials used are safe to live or work in.  Air vents and filters must be cleaned regularly to help reduce the number of airborne pollutants.

  • Click here for more info.

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