At a glance
Since 1998, Australia has had national ambient air quality standards (National Environment Protection Measure for Ambient Air Quality—Air NEPM), which set guideline levels for 7 key air pollutants: carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter (less than 10 microns in size [PM10] and 2.5 microns in size [PM2.5]) and sulfur dioxide. Monitoring against these standards is undertaken at about 75 locations in metropolitan areas and regional towns across Australia, referred to as ‘compliance sites’.
An assessment of air quality from the worst performing (i.e. poorest air quality) of these compliance sites in each jurisdiction showed that air quality is either ‘good’ or ‘very good’ in Australian urban areas.
Levels of lead and nitrogen dioxide have declined markedly in all centres.
Particulate matter has been identified as a hazard to human health. Levels of PM10 now rarely exceed the 24-hour NEPM designed for the protection of human health. However, these good results do not mean that we can be complacent about air quality in Australia as new challenges emerge. The standard for PM2.5, which has previously been an advisory limit only, is frequently exceeded because of extreme events such as bushfires, smog and dust storms. PM2.5 can be transported further and persist for longer in the atmosphere than PM10. We do not fully understand all the processes that lead to PM2.5 formation; thus, in the future when the PM2.5 limit is mandatory, we will be challenged to adhere to this limit. The good news is that more air quality management stations will begin measuring PM2.5 as part of their routine reporting obligations.
Levels of ozone have remained stable since the 2011 state of the environment report.
Despite the complexity of the ambient air system, there is good understanding about several of the most significant pollutants because of the need to reduce air pollution to protect human health. This is particularly true for pollutants that are regulated by national air quality standards and measures.
In this section, we assess the state and trend of the pollutants for which there are national ambient air quality standards. Carbon monoxide is not covered in this update, as there has been little change since SoE 2011. We assess VOCs, including air toxics, which are the subject of a separate air quality standard. In the assessment summaries, we focus on those pollutants that have the largest effect on human health: ozone, PM10 and PM2.5.
Keywood MD, Emmerson KM, Hibberd MF (2016). Ambient air quality: State and trends. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/ambient-air-quality/framework/state-and-trends, DOI 10.4226/94/58b65c70bc372