Fig. 1 contains boxplots of PM10 for each year that data were available. This
Figure confirms the findings of the State of the Air Reports that there has been no
decline in PM10 concentrations in Brisbane, Melbourne and Sydney (Department of
Sustainability, Environment, Water, Population and Communities, 2011;
Department of the Environment and Heritage, 2004). However, for the reasons
mentioned earlier, it is possible that the chemical composition of PM10 in these three
cities has changed over our period of investigation.