DETERMINATION OF HEAVY-METALS, ARSENIC AND SELENIUM IN BARRAMUNDI (LATES-CALCARIFER) FROM LAKE MURRAY, PAPUA-NEW-GUINEA

Elevated levels of Hg have been found in Barramundi fish (Lates calcarifer) from Lake Murray, Western Province, Papua New Guinea. Cu, Pb, Cd, Zn and As which are known to have acute toxic effects on aquatic organisms, could also be accumulated and biomagnified through the food chain. This study investigates the concentration of heavy metals, arsenic and selenium in Barramundi which are an important food resource for the local inhabitants. Total Cd, Cu, Cr, Fe, Mn, Ni, Pb, and Zn concentrations in Barramundi flesh were determined by graphite furnace AAS with matrix modification and platform atomization, following wet digestion with nitric and perchloric acids. As and Se were determined by hydride generation AAS. Hg was determined by cold vapour AAS. The metal concentrations were generally found to be low compared to other published results for unpolluted sites. However, mercury concentrations, were relatively high and exceeded Australian National Health and Medical Research Council (NHMRC, 1987) standards for metals in foods of 0.5 mug g-1 in some individual Barramundi samples.