Atmosphere: Other pollutants
- Author
- Reviewer
- Key findings
- Indicators and summary of status
- Importance
- Pressure and condition
- Response
- References
Author
Phil Kingston, Environmental Protection Agency
Reviewer
Scott McDowall, Environmental Protection Agency
Key findings
- In the past decade there have been no exceedences of the Air NEPM goals for carbon monoxide, lead and nitrogen oxides anywhere in Queensland, or for sulfur dioxide anywhere except Mount Isa, where a major emitter of this pollutant is located. Normal ambient levels (except for sulfur dioxide in Mount Isa) have shown static or declining trends. The sulfur dioxide levels measured in Mount Isa, however, do not constitute a breach of the Mount Isa Mines Limited Agreement Act 1985 (Qld).
Indicators and summary of status
Indicator |
Status of indicator |
Exceedences of NEPM Air Quality standards for carbon monoxide concentrations |
No NEPM exceedences in the past |
Exceedences of NEPM Air Quality standards for lead concentrations |
No NEPM exceedences in the past 10 years-no longer monitored |
Exceedences of NEPM Air Quality standards for nitrogen dioxide concentrations |
No NEPM exceedences of one-hour and annual standards in the past 10 years |
Exceedences of NEPM Air Quality standards for sulfur dioxide concentrations |
Increasing trend in the number of days one-hour and 24-hour NEPM goals were exceeded in Mount Isa but these levels did not constitute a breach of the Mount Isa Mines Limited Agreement Act 1985 (Qld) |
Emissions of air pollutants (total and trends for emission source sectors) |
Small increase in total emissions in the past five years, but no associated increase in ambient concentrations |
Importance
Under the National Environment Protection Measure for Ambient Air Quality 1998 (Air NEPM) six pollutants have been identified as 'criteria pollutants': carbon monoxide, lead, nitrogen dioxide, photochemical oxidants measured as ozone, particles as PM 10 and sulfur dioxide. These pollutants are emitted from a wide range of sources and high concentrations of carbon monoxide (CO), nitrogen dioxide (NO 2), lead (Pb) and sulfur dioxide (SO 2) can affect our health and environment (NEPSC 1998).
Photochemical oxidants (as ozone) and particles have been discussed elsewhere in this chapter. The major sources of emissions of the other pollutants are motor vehicles, industry (mining, power generation and petroleum refining), human activities (hazard-reduction and agricultural burning) and natural events (bushfires).
When inhaled, carbon monoxide reduces the oxygen-carrying capacity of the blood and impairs the release of oxygen to tissues and organs, especially the heart and brain. This can be a serious problem for people with cardiovascular disease.
Elevated levels of nitrogen dioxide cause damage to the human respiratory tract and can increase the severity of respiratory infections and asthma. Nitrogen dioxide is also harmful to vegetation and can reduce visibility. Vegetation exposed to high levels of nitrogen dioxide can be identified by damage to foliage, decreased growth or reduced crop yield.
Sulfur dioxide also adversely affects the respiratory system, aggravates conditions such as asthma and chronic bronchitis, and renders people more prone to respiratory tract infections. Sulfur dioxide when combined with water forms sulfuric acid, the main component of acid rain, which can cause deforestation, acidify waterways to the detriment of aquatic life, and corrode building materials and paints.
Lead can be ingested by the inhalation of airborne particles containing lead; it tends to accumulate in the bones, where it is immobilised and is only slowly eliminated from the body. Lead affects the human central nervous system and can impair neurological and intellectual development in young children.
Table 3.9 shows the Air NEPM standards for carbon monoxide, nitrogen dioxide, sulfur dioxide and lead.
Table 3.9 Air NEPM standards for carbon monoxide, nitrogen dioxide, sulfur dioxide and lead
Pollutant |
Averaging period |
Monitoring concentration |
2008 goal maximum allowable exceedences |
Carbon monoxide |
8 hours |
9.0 ppm |
1 day a year |
Nitrogen dioxide |
1 hour |
0.12 ppm |
1 day a year |
1 year |
0.03 ppm |
none |
|
Sulfur dioxide |
1 hour |
0.20 ppm |
1 day a year |
1 day |
0.08 ppm |
1 day a year |
|
1 year |
0.02 ppm |
none |
|
Lead |
1 year |
0.50 µg/m³ |
none |
Source: NEPC 1998, 2003
Pressure and condition
Air quality is determined largely by the amount and location of the pollutant emitted and the ability of the air mass to transport or disperse emissions. In calm, stable conditions the air mass may remain stagnant, allowing the pollutant to build up to elevated levels. Conversely, windy, turbulent conditions act to disperse the pollutant. Weather conditions cannot be controlled, so management of the pollutant emission, supported by modelling and forecasting of meteorological conditions, is the key to minimising air pollution.
Figure 3.26 shows the major source of each of three pollutants, carbon monoxide, sulfur dioxide and nitrogen oxides.
The source of atmospheric lead in urban areas was almost entirely the burning of leaded petrol in motor vehicles. With the reduction of lead content in fuels and subsequent phasing-out of leaded fuels, measured lead levels fell to less than 0.01 µg/m³, far below the Air NEPM goal level of 0.50 µg/m³, and monitoring ceased in 2002. The lead case study in State of the Environment Queensland 2003 (page 3.40) provides further details on this topic (EPA 2003).
Transport and industry continue to be the major sources of nitrogen oxides, carbon monoxide and sulfur dioxide in Queensland. Motor vehicle use, particularly in south-east Queensland, is expected to increase in line with, and at a greater rate than, the population growth and, depending on public transport and regional activity centre strategies, may increase the number of vehicle kilometres travelled. This in turn will increase the burden of transport-derived pollutants (NO X and CO) in the atmosphere unless mitigated by improvements to transport systems and tighter limits on emissions. See 'Reducing motor vehicle emissions', page 77 .
Motor vehicle fuels in Australia have low sulfur content and are of less concern than industry as a source of sulfur dioxide. Power generation and petroleum refining are the major sources of sulfur dioxide in south-east Queensland; in Gladstone, Townsville and Mount Isa heavy industry is the main contributor. The greatest influence from industrial emissions of SO 2 occurs in Mount Isa as a result of smelting operations. Further details on this topic are provided in State of the Environment Queensland 2003 (EPA 2003).
Even with no exceedences of the Air NEPM standards, the underlying trends for nitrogen oxides and carbon monoxide show a decline, ambient concentrations rarely reaching half of the standard value. The ambient levels of sulfur dioxide in south-east Queensland have continued to decline, and levels seldom reach one-quarter of the Air NEPM one-hour standards; in Gladstone levels rarely reach half the standard (EPA 2004a, 2004b, 2004c, 2005, 2006, unpublished).
In Mount Isa, however, SO 2 concentrations exceed Air NEPM one-hour and 24-hour standards on a number of occasions each year due to smelting operations located in the city but have consistently remained below the annual Air NEPM standard (Figure 3.27).
The smelter operations are regulated to meet air quality limits set in the Mount Isa Mines Limited Agreement Act 1985 (Qld), which correspond to the United States Environmental Protection Agency (USEPA) primary and secondary standards for ambient SO 2 levels (QG 1985).
Ambient SO 2 levels in Mount Isa have gradually decreased in the past ten years as the management of air quality in the populated areas of Mount Isa has improved. In 2000, a sulfuric acid plant began using the majority of the SO 2 emissions previously discharged from the smelter. This allowed the smelter to run at a higher rate of production more often without approaching its set limits and resulted in a rise in the trend of SO 2 concentrations measured in Mount Isa since 2000.
Figure 3.26 Major contributions to total annual emissions of carbon monoxide, sulfur dioxide and nitrogen oxides
Source: EPA
Figure 3.27 Trend in exceedences of the 1-hour, 24-hour and annual NEPM standards for sulfur dioxide in Mount Isa, 1996-2006
Source: EPA 1997, 1998, 2001a, 2001b, 2001c, 2004a, 2004b, 2004c, 2005, 2006, unpublished
Response
Responses to air quality issues can be divided into plans and strategies that target particular source groups, such as motor vehicles and transport, industry and the community, such as Brisbane Air Quality Strategy (BCC 2004).
Control and management of pollutant sources, reliable air quality data, and ongoing action by government-for example, legislation such as the Environmental Protection (Air) Policy 1997b (EPA)- and the community are needed to maintain and improve air quality in Queensland.
To better understand the source and fate of transport-related pollutants the Queensland Department of Main Roads continues to fund an EPA-operated monitoring station at South Brisbane, adjacent to the South East Freeway. Data from this and similar stations are used as a measure against the Air NEPM standards and the attainment of the NEPM's goal of achieving compliance with these standards.
Understanding, managing and controlling emissions from industry are the subject of several actions and strategies. Knowledge of the sources of emissions is derived from inventories of actual and estimated emissions of chemicals of concern in relation to health and the environment. These have been conducted under the umbrella of the National Pollutant Inventory (NPI) and the Air Emissions Inventory South-east Queensland Region, a joint project of the EPA and Brisbane City Council (EPA and BCC 2004). Data from these inventories may be used for modelling the impacts of new developments and for decision making.
The Queensland Government commissioned the Mount Isa Mines Limited Panel Assessment Study in 1998 to assess the impacts of SO 2 emissions on the environment, community and economy of Mount Isa ( EPA 2001d). The study was completed in 2001 and included a number of recommendations.
Xstrata Mount Isa Mines, the current operator of the smelter, has made the following progress towards implementing the recommendations in the study:
- CSIRO has been engaged to continue monitoring SO 2 levels in the area surrounding Mount Isa, using passive samplers. Data are now available for the period 1999-2006.
- Charles Darwin University was engaged to repeat the flora and fauna survey in the area surrounding Mount Isa to look for signs of recovery since the acid plant commenced operation. The new survey, completed in 2005, was inconclusive. No significant improvements in biodiversity were found, but a number of species of animals were observed that had not been observed in the first survey.
- Xstrata Mount Isa Mines has evaluated methods for determining personal exposure to SO 2, but to date a reliable and cost-effective method has not been identified.
- Xstrata Mount Isa Mines has investigated practicable measures to further improve the effectiveness of its air quality control system. The report on the investigation is being finalised.
- Xstrata Mount Isa Mines is evaluating options and methodologies for repeating the community health and perceptions survey to look for signs of improvement since the acid plant began operation.
- Xstrata Mount Isa Mines has begun investigating the feasibility and practicability of the emission control options that were discussed in the study.
Community involvement is encouraged at all stages of planning processes and information is made public through channels such as the NPI web-based emissions database, and the EPA on-line air quality data designed to give communities access to information about pollution in their local area.
References
BCC 2004, Brisbane Air Quality Strategy, Brisbane City Council, Brisbane.
EPA 1997a, Ambient Air Quality Monitoring: 1996 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 1997b, Environmental Protection (Air) Policy 1997, Environmental Protection Agency, Brisbane.
EPA 1998, Ambient Air Quality Monitoring: 1997 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2001a, Ambient Air Quality Monitoring in Queensland: 1998 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2001b, Ambient Air Quality Monitoring in Queensland: 1999 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2001c, Ambient Air Quality Monitoring in Queensland: 2000 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2001d, Mount Isa Mines Limited Panel Assessment Study, Environmental Protection Agency, Brisbane.
EPA 2003, State of the Environment Queensland 2003, Environmental Protection Agency, Brisbane.
EPA 2004a, Ambient Air Quality Monitoring in Queensland: 2001 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2004b, Ambient Air Quality Monitoring in Queensland: 2002 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2004c, Ambient Air Quality Monitoring in Queensland: 2003 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA and BCC 2004, Air Emissions Inventory, South-east Queensland Region, Environmental Protection Agency and Brisbane City Council, Brisbane.
EPA 2005, Ambient Air Quality Monitoring in Queensland: 2004 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
EPA 2006, Ambient Air Quality Monitoring in Queensland: 2005 Annual Summary and Trend Report, Environmental Protection Agency, Brisbane.
NEPC 1998, National Environment Protection Measure for Ambient Air Quality, National Environment Protection Council, Adelaide.
NEPC 2003, National Environment Protection (Ambient Air Quality) Measure, National Environment Protection Council, Adelaide.
QG 1985, Mount Isa Mines Limited Agreement Act 1985, Queensland Government, Brisbane.
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Last reviewed 11 May 2011
Last updated 13 February 2008