Heavy metals distribution in cetaceans stranded at west and north coasts of Sabah, Malaysia

Document Type: Primary Research paper

Authors

Abstract

Heavy metals distribution in the liver, kidney, heart, lung, muscle, melon, muscle and blubber of 5 cetaceans (2 short-finned pilot whales, 2 finless porpoises and 1 spinner dolphin) stranded at the west and north coasts of Sabah, Malaysia in 2015 were examined in this study as a first attempt to establish baseline information. Cd, Cr, As, Pb, Cu, Mn, Fe, Se, and Zn were generally found to be low in these cetaceans. Calves, adolescents, and adult cetaceans examined exhibit differential metal distribution which is normal since diet and maturity stage play the major role on this. Similar pattern of distribution was also found regardless of species. Concentrations Cu, Zn, Fe and Mn in liver and kidney were found to be not affected by species or maturity.  Selective accumulation of Cd was found in kidney of adolescent short-finned pilot whale and spinner dolphin (98.65 and 35.04 µg g-1 dwt or 54.28% and 67.13% respectively). As and Cd in the calf finless porpoise were significantly high in the muscle compare to other tissues (3.52 and 3.79 µg g-1) which could be due to redistribution of harmful metals to protect main organs from toxicity. However, no specific metal toxicity or pollution of local marine environment was found. 
Heavy metals distribution in the liver, kidney, heart, lung, muscle, melon, muscle and blubber of 5 cetaceans (2 short-finned pilot whales, 2 finless porpoises and 1 spinner dolphin) stranded at the west and north coasts of Sabah, Malaysia in 2015 were examined in this study as a first attempt to establish baseline information. Cd, Cr, As, Pb, Cu, Mn, Fe, Se, and Zn were generally found to be low in these cetaceans. Calves, adolescents, and adult cetaceans examined exhibit differential metal distribution which is normal since diet and maturity stage play the major role on this. Similar pattern of distribution was also found regardless of species. Concentrations Cu, Zn, Fe and Mn in liver and kidney were found to be not affected by species or maturity.  Selective accumulation of Cd was found in kidney of adolescent short-finned pilot whale and spinner dolphin (98.65 and 35.04 µg g-1 dwt or 54.28% and 67.13% respectively). As and Cd in the calf finless porpoise were significantly high in the muscle compare to other tissues (3.52 and 3.79 µg g-1) which could be due to redistribution of harmful metals to protect main organs from toxicity. However, no specific metal toxicity or pollution of local marine environment was found. 

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