AIR QUALITY

Overall, air quality in Australia is relatively good. Fine particle health standards (Endnote 1) were exceeded in the selected urban areas on average between one and three days each year between 1997 and 2007 with the exception of 2002, 2003 and 2006. In 2002 and 2003, standards were exceeded more often, mainly because of severe bushfires and dust storms around the Sydney and Melbourne areas, which caused the National Environment Protection Measure (NEPM) for fine particle (PM₁₀) concentrations in the air to be exceeded on 13 days in Sydney (Liverpool) in 2002 and 10 days in Melbourne (Footscray) in 2003. This NEPM standard was also exceeded on eight days in Brisbane (Rocklea) in 2002. In 2006 it was exceeded on 11 days in Adelaide (Netley), mostly due to smoke haze from bushfires and strong winds and windblown dust. The standards were also exceeded on 11 days in Melbourne in 2006, with fire the likely cause for 10 of those days.

ABOUT THE INDICATOR

MAP reports on two dimensions of the air and atmosphere: urban air quality and greenhouse gas emissions.

Poor air quality has a range of negative impacts: it can cause health problems, damage infrastructure, reduce crop yields and harm flora and fauna. Air pollution occurs both naturally and as a result of human activities. Australians consistently rank air pollution as a major environmental concern. The concentration of fine particles in the atmosphere is the form of air pollution about which many health experts in Australia are most concerned.

The headline indicator summarises data from continuous air monitoring stations in Sydney, Melbourne, Adelaide, Perth and Brisbane to report on the number of days when the National Environment Protection Measure (NEPM) for fine particle (PM₁₀) concentrations in the air was exceeded (Endnote 1). It is important to note that daily changes in the measurement of air quality depend both on ambient conditions, like wind direction, and the monitoring station’s proximity to pollution sources. Further, high concentrations of fine particles from irregular events, such as bushfires, can obscure the longer trend in levels produced by regular sources like car emissions. In general, the common air pollutants are found at higher levels in urban and industrial areas than in rural Australia.

SEE ALSO

The air and atmosphere: air quality - Measures of Australia's Progress, 2006
Themes - Environment & Energy
State of the Environment reporting

ENDNOTES

1. Fine particles in the atmosphere come from a wide variety of sources, including soil (dust), vegetation (pollens and fungi), sea salt, fossil fuel combustion, biomass burning (including bushfires) and industry. Particles suspended in air have the ability to penetrate the lower airways of the lung if smaller than 10 micrometres in diameter (referred to as PM₁₀). Increasing evidence suggests the acute health effects may, in fact, be the result of exposure to very fine particles, such as those smaller than 2.5 micrometres in diameter (referred to as PM_2.5). It is these finer particles that are the main cause of urban haze, which typically appears white. Most of these particles are generated by people, rather than occurring naturally. The human health effects are many and depend on the size and chemical composition of the particles. Particles can aggravate existing respiratory and cardiovascular disease and asthma, can affect eyesight and cause allergies.

Data are from representative sites in Sydney (Liverpool), Melbourne (Footscray), Brisbane (Rocklea), Perth (Duncraig) and Adelaide (Thebarton from 1997 to 2002 and Netley for 2003 to 2007), and have been averaged in proportion to each city's population. The data are the number of days when the National Environment Protection Measures (NEPM) average daily PM₁₀ standard is exceeded. The NEPM standard is a maximum concentration of 50 micrograms per cubic metre with a maximum allowable exceedence of five days per year. The PM₁₀ data from each state environmental protection agency (EPA) was obtained using the Tapered Element Oscillation Microbalance method, which continuously monitors PM₁₀ levels in the air averaged over a 24 hour period. 1997 was the first year all of the five EPAs used this method. Compliance with the standards can only be demonstrated if data capture is at least 75% in each quarter of the year. Data capture did not meet the target for Footscray in 2006 as this monitoring station did not operate continuously during the year. It was taken off-line for upgrading.

2. Australian Bureau of Statistics 2008, Regional Population Growth, Australia, 2006-07, cat. no. 3218.0, ABS, Canberra.

Department of Environment and Climate Change (NSW) 2008, Search air quality data, Department of Environment and Climate Change (NSW), Sydney, viewed 20 January 2009.

Department of Environment and Conservation (WA) 2008, Air Quality Tools, Systems and Data, Department of Environment and Conservation (WA), Perth, viewed 20 January 2009.

Environmental Protection Agency South Australia 2008, South Australia's Air Quality 2007, Environmental Protection Agency South Australia, Adelaide, viewed 20 January 2009.

Environmental Protection Agency Victoria 2008, Air Monitoring Report 2007: Compliance with the National Environment Protection (ambient air quality) measure, Environmental Protection Agency Victoria, Melbourne, viewed 20 January 2009.

Queensland Government Environmental Protection Agency 2008, Queensland 2007 Air Monitoring Report, Queensland Government Environmental Protection Agency, Brisbane, viewed 20 January 2009.

LINK TO THE DETAILED SUMMARY