Bioaccumulation of 12 trace elements in the tissues of the nautilus Nautilus macromphalus from New Caledonia

Soils in New Caledonia are particularly rich in metals among which Fe and N i are intensively exploited. Due to important natural erosion in tropical l atitudes and to mining activities, coastal waters are enriched in Co, Cr, F e and Ni, In deeper waters lives a cephalopod species which is considered a s a living fossil, the nautilus Nautilas macromphalus. In this study, 12 tr ace elements were analysed in the tissues of 4 nautilus specimens. Results showed high metal concentrations compared to data available for cephalopods from temperate waters. These concentrations were often in the same order a s those encountered in bivalves or gastropods from contaminated areas. Rela tively high concentrations of Ni and Cr in the haemolymph strongly suggest a high exposure of N. macromphalus to these metals. Among the tissues, the digestive gland has the highest concentrations of Cd, Co, Fe, V and Zn whil e for Ag, Al, As, Cr and Ni, renal and pericardial appendages exhibited the highest values. Despite this, the digestive gland contained the largest qu antities of all metals with the exception of As and Mn which were mainly fo und in the body muscular remains. These results highlighted the major role of digestive gland and excreting organs in the metabolism of metals in thes e cephalopod species. (C) 2000 Elsevier Science Ltd. All rights reserved.