COMPARATIVE STUDIES ON TRACE-METAL LEVELS IN MARINE BIOTA .2. TRACE-METALS IN KRILL, KRILL PRODUCTS, AND FISH FROM THE ANTARCTIC SCOTIA SEA

In whole krill, krill muscle tissue, krill products and in fillets of the antarctic fish Notothenia rossi marmorata, Dissostichus eleginoides, and Notothenia gibberifrons the levels of Cd, Pb, Cu, Ni, Hg and As have been determined. The methods applied were electrothermal AAS for Cd, Pb, Cu, and Ni, cold-vapour and hydride-generation AAS for Hg- and As, respectively, usually after HNO, pressure decomposition and for As followed by a HClO4/H2SO4 treatment. Quality control was performed by analysis of appropriate Standard Reference Materials and working standards and by intercomparison with differential pulse anodicstripping voltammetry (DPASV) for Pb and Cd. The mean values obtained related to fresh weight for krill muscle meat (46 ng Cd/g, ≦ 50 ng Pb/g, 380 ng Cu/g, 130 ng Ni/g, ≦ 20 ng Hg/g, and 340 ng As/g) and fillets of antarctic fish (≦ ng Cd/g, ≦ 100 ng/Pb/g, ≦ 200 ng Cu/g, ≦ 150 ng Ni/g, ≦ 50 ng Hg/g, and 300-1500 ng As/g) confirm the absence of toxic risks for human food according to the present knowledge. Due to the somewhat higher, but not excessive, trace metal contents of krill products, these should be more suitable as a protein rich animal feed. © 1979 Bergmann Verlag.