In the Air.

Chemicals are released into the air through industrial emissions, burning fuels, vehicle exhaust, spraying of pesticides, off-gassing of building materials, and consumer products like cleaning and personal care products. In addition, natural events such as forest fires can also cause air pollution. Outdoor air pollution can enter buildings through open doors and windows, air handling systems, and cracks in structures.

As you breathe, chemicals can enter your body and cause irritation or disruption of your cardiovascular, endocrine, respiratory, and other body systems.

Some common chemicals found in air include:

Particulate matter (PM2.5):

very small particles (about 30 times smaller than the width of a human hair). Particles are present in dust, soot, and smoke and can get deep into your lungs or even into your blood.  Sources can include diesel exhaust, woodstove smoke, forest fires, and factory emissions. Particles can cause eye, lung, and throat irritation, trouble breathing, lung cancer, low birth weight, and worsen asthma and heart disease symptoms.

Ground level Ozone:

created in when nitrogen dioxide from vehicle exhaust and other sources combines with volatile organic compounds in the presence of sunlight. Ozone levels can be especially high on hot sunny days and acts as a powerful irritant to your airways, causing the muscles of the airway to constrict. These effects are even more serious in people with asthma or other lung diseases.


naturally occurring radioactive gas that you cannot smell, taste, or see. In Canada, radon exposure is the leading cause of lung cancer in non-smokers. If you smoke and are exposed to radon, you are at an even higher risk of developing lung cancer. Radon is present in all buildings.


hundreds of synthetic chemicals added to cosmetics, cleaning supplies, and other household products. These chemicals can trigger allergies, migraines, lead to the development of asthma, and other health effects.

Carbon monoxide (CO):

colourless, odourless gas that is produced as a result of incomplete burning of carbon-containing fuels. Many Canadians die every year and thousands of others become ill or need medical attention because of carbon monoxide poisoning related to residential combustion appliances. Any fuel-burning device that is not adequately vented and maintained can be a potential source of CO, including: fireplaces, wood and coal stoves, barbecues, gas appliances, space heaters, charcoal grills, camp stoves, automobile exhaust, gas-powered lawn mowers and tools, and cigarettes. Breathing in low levels of carbon monoxide can cause fatigue and increase chest pain in people with chronic heart disease. At very high levels, carbon monoxide causes loss of consciousness and death.

What You Can Do

  • Choose outdoor activity areas away from industrial emissions or busy roads
  • Learn to use the Government of Canada’s Air Quality Health Index
  • Reduce the use of your personal vehicle, and consider cleaner options when purchasing a new vehicle
  • Test your home for radon, and install a mitigation system if needed
  • Avoid scented products
  • Ensure gas appliances such as furnaces, fireplaces, stoves, ranges, water heaters, and clothes dryers are properly ventilated. Install a CO alarm with an audible alarm
  • Use kerosene, gas, or diesel space heaters only in well ventilated areas woodstove smoke, forest fires, and factory emissions. 

We provide science-based information gathered from trustworthy sources. For further reading, you can check out our sources, which include:

  • Canadian Lung Association: Scents 

  • Centers for Disease Control and Prevention: Particle Pollution 

  • Canadian Council of Ministers of the Environment: State of the Air 

  • Government of Canada: Air Quality Health Index 

  • Government of Canada: Radon 

  • Government of Canada: National Pollutant Release and Inventory 

  • Government of Canada: National Air Pollution Surveillance Program 

  • New Brunswick Lung Association: Carbon Monoxide 

  • United States Environmental Protection Agency:  Health Effects of Ozone Pollution 

  • United States Environmental Protection Agency: Report on the Environment. Indoor Air Quality.