Particulate matter (PM10 and PM2.5)

Particulate matter, also known as particle pollution or PM, is a term that describes extremely small solid particles and liquid droplets suspended in air. Particulate matter can be made up of a variety of components including nitrates, sulfates, organic chemicals, metals, soil or dust particles, and allergens (such as fragments of pollen or mould spores). Particle pollution mainly comes from motor vehicles, wood burning heaters and industry. During bushfires or dust storms, particle pollution can reach extremely high concentrations

The size of particles affects their potential to cause health problems:

• PM10 (particles with a diameter of 10 micrometres or less): these particles are small enough to pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health effects.
• PM2.5 (particles with a diameter of 2.5 micrometres or less): these particles are so small they can get deep into the lungs and into the bloodstream. There is sufficient evidence that exposure to PM2.5 over long periods (years) can cause adverse health effects. Note that PM10 includes PM2.5.

Potential health effects from exposure to particulate matter:
There are many health effects from exposure to particulate matter. Numerous studies have showed associations between exposure to particles and increased hospital admissions as well as death from heart or lung diseases. Despite extensive epidemiological research, there is currently no evidence of a threshold below which exposure to particulate matter does not cause any health effects. Health effects can occur after both short and long-term exposure to particulate matter.

Short-term and long-term exposure is thought to have different mechanisms of effect. Short-term exposure appears to exacerbate pre-existing diseases while long-term exposure most likely causes disease and increases the rate of progression.

• irritated eyes, nose and throat
• worsening asthma and lung diseases such as chronic bronchitis (also called chronic obstructive pulmonary disease or COPD)
• heart attacks and arrhythmias (irregular heart beat) in people with heart disease
• increases in hospital admissions and premature death due to diseases of the respiratory and cardiovascular systems.
  

• reduced lung function
• development of cardiovascular and respiratory diseases
• increased rate of disease progression
• reduction in life expectancy.
  

To learn more, visit our section ‘Who is affected by air pollution’ and ‘Simple steps to protect your health’. For further information on wood-burning heaters, bushfire smoke and dust storms please see our section on air quality factsheets. To learn more about the air quality index, please see our section on air quality index.