CONCENTRATIONS OF 24 ELEMENTS IN BLUEFIN TUNA, THUNNUS-THYNNUS FROM THE NORTHWEST ATLANTIC

Fourteen muscle samples of bluefin tuna, Thunnus thynnus, collected in the area of the Virgin Rocks, on the Grand Banks of Newfoundland, Canada were analyzed for total mercury (Hg) by cold vapor atomic absorption (AA) spectroscopy and for 23 other elements including priority pollutants and biologically essential elements, by inductively coupled plasma mass spectrometry (ICP-MS). The order of decreasing concentration (ppm, dry weight) for the 24 elements was Mg (680), Ca (215), Fe (29), Zn (17), Hg (3.4), As (3.2), Se (2.2), Rb (1.4), Al (1.0), Cu (1.0), Sr (0.6), B (< 0.4), Mn (0.2), Cs (0.1), Ba (0.03), Cd (0.03), Pb (< 0.03), Co (0.01), Mo (< 0.01), Ag (0.004), Li (< 0.007), U (< 0.006), V (0.003) and La (< 0.001). With respect to priority contaminants, Hg and As concentrations were generally higher than those reported in various tuna species but comparable to levels in other large palagic fish; lead was undetectable, while Cd was low. The concentrations of fifteen elements are reported for the first time.