Wood Burning and Possible Health Effects

When the weather cools woodstoves and fireplaces are commonly used to provide additional heat in many homes and cottages.  Since combustion in woodstoves is less complete than in oil or gas furnaces, pollutant emissions from them can be much greater.  These by-products should be vented to the outside; however, leaks and improper operation of these appliances can cause emissions to the indoors.

The smoke produced from burning wood in fireplaces and woodstoves is a major source of particulate matter air pollution.  Not only does wood smoke lower indoor and outdoor air quality, research studies have established that exposure to wood smoke may lead to serious health effects.  Wood smoke emissions contain components such as carbon monoxide, nitrogen dioxide, particulate matter, polycyclic aromatic hydrocarbons, aldehydes and phenols.

Health effects of carbon monoxide
Carbon monoxide binds 210 times more strongly to blood than oxygen thereby reducing the oxygen carrying capacity of blood.  At high concentrations and extended lengths of exposure, death can occur.

Health effects of nitrogen dioxide
Children and adults exposed to nitrogen dioxide for extended lengths of time may experience impaired functioning of the respiratory system such as bronchial congestion.

Health effects of particulate matter
Particulate matter is a mixture of solid and liquid droplets present in the air.  Particles that are 10 microns in diameter or smaller are of a health concern because they are small enough to be inhaled into the lungs.  The smaller the particle, the deeper it can be inhaled and the more serious the potential health effects.  Particulate matter can affect the respiratory system causing increases in the occurrence of mild respiratory problems and aggravating asthma.

Health effects of polycyclic aromatic hydrocarbons
Exposure to this large group of organic compounds can be through skin contact, inhalation or ingestion.  Some of these compounds are known to be carcinogenic and exposure to these substances should be minimized.

Tips for burning wood safely
If you burn wood in your home, there are a few important steps to reduce harmful emissions from your fireplace or woodstove.  These steps include:

• Use the cleanest technology available.

• Burn only clean, dry seasoned hardwood.  Wet wood burns poorly and produces more smoke.  Softwood produces more emissions and deposits inside your chimney.

• Never burn painted or treated wood, trash or coloured paper which gives off harmful chemicals and more smoke as they burn.

• Regularly clean and maintain your stovepipe and chimney.