BASE-LINE TRACE-METAL CONCENTRATIONS IN NEW-SOUTH-WALES COASTAL WATERS

Concentrations of ten trace elements at five localities in New South W ales coastal waters were measured by ultratrace sampling and analysis. Mean concentrations of cadmium (2.4 ng L-1), copper (31 ng L-1), nick el (180 ng L-1), lead (9 ng L-1) and zinc (<22 ng L-1) are among the l owest reported in the Southern Hemisphere and are consistent with rece nt oceanographic data for the surface waters of the Pacific Ocean, Wat ers from the southernmost sampling locality (Eden) contained higher ph osphate, silicate, cadmium and nickel, but lower chromium concentratio ns than waters from the other four localities, reflecting the inputs o f water from the Tasman Sea in the south compared with the dominance o f waters from the Coral Sea along the rest of the coast. Cadmium conce ntrations were positively correlated with both phosphate and silicate. Chromium and lead concentrations were also significantly correlated. It is likely that a major source of lead is atmospheric deposition. Th e trace metal concentrations were comparable to those in the surface w aters of the Pacific Ocean, indicating that fluvial inputs or processe s occurring in the coastal margin were of limited importance in determ ining trace metal concentrations.