Trace Element Accumulation in 20 Species of Fishes from Lake Baikal, Caspian Sea, Black Sea and Japanese Coastal Waters

Abstract

Trace element concentrations (Li, Be, V, Cr, Mn, Co, Cu, Zn, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Hg, Tl, Pb, Bi, Th and U) in the muscle and whole body of 20 species of fishes collected from Lake Baikal, Caspian Sea, Black Sea and Japanese coastal waters were determined in order to compare with each level. Cobalt, As, Hg and Tl concentrations in the marine fishes were higher than those in blackish and fresh water fishes such as Black Sea, Caspian Sea and Lake Baikal. Chromium, Co, Rb, Tl and Pb concentrations in the Baikal fishes were higher than those in species from other area. In contrast, lower concentrations of Li, As and Th were found in Baikal fishes. Relatively higher concentrations of Zn and Sr and lower levels of Cr, Rb and Cs were observed in Caspian fishes when compared with individuals from other waters, although only one species could be analyzed. Vanadium and Cu concentrations in Black Sea samples were higher than those of other fishes, however Li concentrations in Black Sea species were low.
From results of species-specific accumulation, Hg concentration in the fishes was due to tropic levels relating with body size and life span. Toxic elements such as Ag, Hg and Tl and alkali and alkaline earth metals such as Cs and Sr levels in the body of fishes might be concentrated with growth and amount of diet intake, although almost all element including essential metals were diluted with increasing body size. Therefore, above elements such as Hg, Tl, Sr and Cs would reflect environmental levels. Moisture and fat contents in the tissues and inter-element relationships might be also effective factors to decide the trace element levels in the fish bodies.