Outdoor Air Quality

The quality of the air we breathe can affect our health. In the District of Thunder Bay, the most common threat to air quality is forest fires. The role of the Thunder Bay District Health Unit is to raise awareness and provide information about this health concern.

Forest Fires

Smoke from forest fires – as well as other wood-fuelled fires – is made up of a complex mixture of gases and fine particles produced when wood and other organic matter burn. The biggest health threat from smoke comes from fine particles. The term PM (for particulate matter) is used to describe this type of pollutant. Other components of smoke include toxic gases like carbon monoxide, sulphur dioxide and ozone.

Particles smaller than 10 microns (PM 10) can make it past our body's defences and lodge in our airways or bronchial tubes. PM 2.5 (particles smaller than 2.5 microns) are especially dangerous and can reach into the air sacs of our lungs and into the bloodstream.

These smoke particles can build up in our bodies and cause a number of immediate health problems including burning eyes, runny noses, scratchy throat, irritated sinuses and headaches. High levels of PM can cause mucus and soot build up in the lungs. This makes our bodies more susceptible to infections such as sinusitis or bronchitis.

Children, older adults and pregnant women are most at risk. The particles also can aggravate existing heart and lung disease such as congestive heart failure, chronic obstructive pulmonary disease (COPD), emphysema and asthma. People with a prior heart attack are at higher risk for a second heart attack.

How to Reduce the Risk of Smoke Exposure

  • If it looks smoky outside, avoid outdoor physical activity.
  • Stay indoors with the windows and fresh air intakes closed.
  • Avoid smoke-producing appliances such as wood stoves and candles.
  • Do not smoke tobacco inside – smoking puts added stress on your lungs and those around you.
  • If you have asthma or other respiratory condition, be vigilant about avoiding smoke and taking your prescribed medicine, and talk to your health care provider about extra precautions.
  • Seek medical treatment if you have uncontrolled coughing, wheezing or choking, or if breathing difficulty does not subside indoors.

Health Canada Resources

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