7.5 Indoor Air Pollutants

2 min readjanuary 8, 2023

Joshua Nielsen

Joshua Nielsen

AP Environmental Science ♻️

252 resources
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  • Asphyxiant
  • Carbon Monoxide
  • Radon-222
  • Formaldehyde
  • Asbestos
  • Sick Building Syndrome
Indoor air pollutants are substances that are present in the air inside buildings and homes and can be harmful to human health. These pollutants can come from a variety of sources, including tobacco smoke, building materials, household products, and outdoor air that enters the building.

Carbon Monoxide - the Silent Killer


Image Courtesy of Pixabay

When incomplete combustion occurs, carbon monoxide is one of the gasses released. If you have a fireplace, it is important to open the flue or your house will fill with the smoke and CO. Burning fossil fuels also creates CO, this includes your car. 
Your blood cells easily take in O2 in order for you to live. However, CO is absorbed by your cells faster. Your body is not able to use the CO. This causes you to pass out due to asphyxiation. Never leave a vehicle running in a closed garage. The carbon monoxide is colorless and odorless and will accumulate in the air. 


Radon-222 is the chemical name for the radioactive material that is found in the Earth’s crust. As uranium decays, radon is produced. This radioactive gas can leach through the soil and enter basements, foundations, or crawl spaces under a house. It has also been found dissolved in well water.
Since it is a radioactive material, radon can cause certain cancers. The radon can be inhaled or ingested (drinking contaminated well water) thus releasing the radiation internally. There is also radon in cigarettes. 

Image Courtesy of Pixabay


Inside many homes are sources of air pollutants that were purchased intentionally. Volatile organic compounds are found in many household items. Formaldehyde is often referred to as the nasty smelly odor during high school dissections. It is commonly used in upholstery, furniture, and carpets. That ‘new car/carpet/chair smell’ is a VOC. 


This material was commonly used in ceilings and insulation for its fire-retardant properties. Unfortunately, if small fibers were inhaled, it could cause forms of lung cancer. Today, it takes trained professionals to seal or remove asbestos from a home or building. It is treated as a hazardous material.

Sick Building Syndrome

In an effort to reduce heating and cooling costs, offices and homes try to seal the space from the outside air. This may be done with door and window stripping and keeping windows closed. This creates a problem as any indoor pollutant has no means of escape and can cause the illness: Sick Building Syndrome. One cause of this is the build-up of ozone in an office building from the use of copier machines.
In many cases, sick building syndrome can be alleviated by opening a window and allowing a breeze to circulate through the air. There are also a variety of plants that can absorb various chemicals from the air thus cleaning it.
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