We often hear about air quality and air pollution, but what do we know about pollution? How does one categorize air as polluted or unpolluted?
There are several types of pollution: the type that consists of toxic gases, the type that consists of particulate matter, acid rain, and ozone pollution. Human activity is one of the major sources of all primary outdoor pollution. Chemicals that are released by some sort of human activity include:
- Carbon monoxide (vehicular exhaust)
- Carbon dioxide (greenhouse gas released during any type of combustion)
- Nitrogen oxides (high temperature combustion)
- Sulphur oxides (coal and petroleum combustion)
- Chlorofluorocarbons or CFCs (from aerosols – banned currently)
- Volatile organic compounds (VOCs) – (industrial sources)
- Toxic heavy metals (lead, copper, cadmium, etc….much from electronics)
- Particulates – (burning fossil fuels and industrial processes)
- Ammonia – (agricultural processes)
- Radioactive particles – (natural radon and nuclear accidents/explosions)
- Noxious fumes – (usually from industry and sewage)
Secondary pollution is pollution that is caused by the reaction of a primary pollutant with the atmosphere. These sources include:
- Ozone at the ground level – (combustion of fossil fuels)
- Particulate matter – (light + primary gas pollutants)
- Peroxyacetyl nitrate – (VOCs + nitrogen oxides)
Other hazardous chemicals found in the atmosphere that are attributable to human activity include formaldehyde, chloroform, acetaldehyde, carbon tetrachloride, benzene and 1,3-butadiene.
We tend to take for granted that the air we breathe indoors is filtered and safe. But there are potential dangers that we must understand in order to create a safe working and living environment for ourselves and for our families.
- More and more states are passing laws banning smoking inside public buildings. Secondhand smoke was one of the major sources of indoor pollution and creates both gaseous pollution in the form of carbon monoxide (and other toxic substances), and very fine particulate matter that can easily lodge in the lungs. We all know the numerous illnesses that can result from the inhalation of tobacco smoke.
- Radon is a natural radioactive gas that is emitted from rocks beneath buildings. Because of its source location, radon is typically found in high density in the basement of homes and buildings. Radon can cause lung cancer.
- Carbon monoxide is emitted by fossil fuel combustion and smoking. If you have an oil burner to heat your home or a fossil fuel space heater, this gas can be a dangerous presence in your home. People who heat their homes with their natural gas ovens opened run the risk of poisoning their household with carbon monoxide. Carbon monoxide can kill without warning.
- Mold and fungi release spores into the environment as small particulate matter and can cause serious illness and/or allergies. Asthmatics react quite severely to mold spores.
- Bacteria such as Legionella can be an undetected contaminant of an indoor environment until a number of people fall ill. Some of these bacteria are very dangerous to the lungs and can cause pneumonia or other serious respiratory diseases.
- Volatile Organic Compounds (VOCs) are everywhere in our household from cleaners to detergents to synthetic fabrics. Although some laws have been put in place to decrease their use, it is difficult to regulate such ubiquitous compounds.
- Dust and dust mites are also found everywhere. Dust is produced mostly by dead human skin flakes. Dust mites feed on these skin flakes. Humans can be highly allergic to the mites and must somehow find ways to decrease their number indoors.
Obviously humans have a challenge in front of them, to clean our air and maintain air quality both indoors and outdoors such that it is safe to breathe. One of the position statements of the American Lung Association is that the ‘air we breathe won’t cause or in any way worsen lung disease’.