Distribution of poycyclic aromatic hydrocarbons in sediments from estuaries of south-eastern Australia

Abstract

Concentrations (µg/kg dried sediment) of the polycyclic aromatic hydrocarbons (PAH) benzo[a]pyrene (B[a]P) and perylene have been measured in sediments taken from three locations in south-eastern Australia: a highly urbanized estuary (Yarra River), a marine bay (Corio Bay), and an estuary remote from urban activity (Mallacoota Inlet). Most concentrations of B[a]P lay in the range 200-800 µg/kg and these values are comparable to values found in similar situations in other parts of the world. The minimum concentration of B[a]P observed was 20µg/kg in Mallacoota Inlet; the maximum concentration was 6800 µg/kg at one location in a tributary of the Yarra River where the sediment was visibly contaminated with oil.

The ratio of B[a]P:perylene was 1.0-2.0 in all three areas and this ratio is significantly lower than for aerosols in the Melbourne atmosphere, suggesting that deposition of aerosol is not the major contributor to PAH in sediments.