Concentrations of Mercury in Fresh and Salted Marine Fish From the Canary Islands

A statistical study of recovery has been carried out in five mineralization procedures: i) HNO₃/H₂SO₄ (1:1), 45°C/15 h; ii) HNO₃, 100°C (teflón pump)/l h.; iii) HNO₃/H₂SO₄ (1:1), 100°C (teflon pump)/l h; iv) H₂SO₄/HCI (1:1), 100°C (teflon pump)/l h; and v) Lumaton, 45°C/24 h, for determination of mercury (cold vapor - A.A.S.) in muscle of fish. Only in method 1 there is no evidence of the systematic error (P > 0.05). This method was applied to 449 samples of fresh and salted fish. Mean concentrations of mercury ranged of 0.014 ppm ( Pagellus erythrinus ) to 0.970 ppm ( Lepidopus caudatus ) for fresh fish, and for salted fish between 0.043 ppm ( Diplodus sargus cadenati ) and 0.172 ppm ( Galeorhinus galeus ). One can conclude that the low mercury level of analyzed samples was lower than fish species from some polluted areas of the Mediterranean Sea. No significant differences were observed between the mean concentrations of fresh and salted fish.