Trace heavy metals in fine and coarse aerosols in four major Australian cities.

Abstract

A study, funded by Department of Environment and Heritage's Living Cities Program, collected samples of both PM2.5 (fine particles) and PM2.5-10 (coarse particles) over a 12-month period during 2003-2004 in Melbourne, Sydney, Brisbane and Adelaide. 24-hour aerosol samples were collected in six-day cycle using dichotomous samplers at two sites from a typical urban and typical suburban monitoring site operated by the state EPA in each city. ANSTO performed gravimetric analysis and accelerator-based ion beam analysis which provided information on F, Na, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Ni, Zn, Sr, Br and Pb to determine the elemental composition of the aerosols. The overall average concentration of fine particles was 5.6 μg/m3, while PM2.5-10 10 μg/m3. The concentrations of fine particles did not exceed USEPA air quality standards and proposed 24-hour and annual NEPM goal. The elemental composition of PM2.5-10 particles was dominated by Si, Fe, Al, K, Ca, Na and Cl, while black carbon, S, Na and Cl dominated the fine fraction. V, Cr, Ni and Co were below the minimum detection limits in most of the samples. The concentrations of Mn, Cu, Zn and Pb were measured below 0.01 μg/m3 in the coarse particles and below 0.02 μg/m3 in fine aerosols. The measured concentrations of heavy metals exhibit spatial and temporal variations.