Composition of woodsmoke

Woodsmoke particles consist mainly of tiny droplets of oils and tars that escape from the wood heater or open fireplace due to incomplete combustion. They are released as vapour, which forms droplets as it cools. These tiny droplets are what we observe as visible smoke plumes. Almost all particles in woodsmoke are in the PM2.5 category, with most particles less than 1 micron. 

The components of woodsmoke include:

• fine particles (PM2.5)
• nitrogen oxides (NOX)
  
• carbon monoxide (CO)
  
• carbon dioxide (CO2)
• methane (CH4)
  
• volatile organic compounds (VOC)
• aldehydes
  
• benzene, toluene and xylenes (BTX)
• polynuclear aromatic hydrocarbons (PAH)

Many of the same chemicals are found in both wood smoke and tobacco smoke, which is not surprising as both result from incomplete combustion of organic material. 

Exposure to woodsmoke can:

• Irritate eyes, lungs, throat and sinuses and cause coughs in otherwise healthy people.
• Reduce lung function, especially in young children
• Interfere with normal lung development in infants and children
• Increase severity of existing lung diseases such as asthma, emphysema, pneumonia and bronchitis
• Depress the immune system and damage the layers of cells in the lungs that protect and cleanse the airways
• Increase risks of heart attacks
• Trigger headaches and allergies

Woodsmoke is a major source of fine particles (PM2.5) in many parts of Australia in winter.

Further Information

• Woodsmoke Site - AAQG
  
• Harmful Substances in Woodsmoke EPA, Tasmania
• Why is woodsmoke a problem?
• Woodsmoke and your health - advice from the Australian Lung Foundation
• NSW Health Factsheet
• Health Effects of Woodsmoke - Environment and Human Health, Inc in U.S.A.