Fine particulate matter generally refers to particles measuring less than 2.5 microns (PM2.5). Outdoor sources of PM2.5 include combustion engines (in all types of vehicles), coal dust, bush fires and land clearing. Inside, PM2.5 can be generated from mould, cooking and fireplaces.
Short term exposure to PM2.5 can cause eye, nose and throat irritation, and flu like symptoms of runny nose and shortness of breath. PM2.5 can also affect lung function and exacerbate asthma and heart disease. Scientific studies show long term exposure to PM2.5 to increase risks of cancer and heart disease.