Sources of fine particle lead, bromine, and elemental carbon in southeastern Australia

In urban areas, motor vehicle exhaust is often a major source of fine particle lead, bromine, and elemental carbon (EC). However, other sources of these species exist and need to be identified. In this study, the possible existence of additional sources of fine particle lead, bromine, and elemental carbon are identified using regression analysis based on the data collected at 24 sampling sites of the Aerosol Sampling Program (ASP) in southeastern Australia. Both the regression slopes and intercepts provide useful information on source composition and site specific source structure. The existence of a non-zero intercept suggests additional sources of lead other than motor vehicles affect sites in the Hawkesbury Basin as well as in heavily industrial areas in the Newcastle and Wollongong areas. Additional sources of elemental carbon were found to primarily affect inland sites where agricultural activities such as held burning occurred or the sites are adjacent to bushland. Minor additional sources of bromine were detected particularly at the coastal sites and are thought to arise from natural marine sources.