Trace metals in the muscle tissues of skipjack tuna (Katsuwonus pelamis) in Sri Lanka

Abstract

Non-essential trace metals, namely mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (As), and essential trace elements copper (Cu), iron (Fe) and zinc (Zn) found in muscle tissues were analysed and compared between female, male skipjack tuna (SJT) in the Indian Ocean, Sri Lanka. Forty-four (20 female and 24 male) individual specimens of SJT were investigated using an atomic absorption spectrometer. The mean trace elements of the male fish were determined to include Hg, 0.12; Cd, 0.02; As, 0.85; Pb, <0.52; Cu, 5.45; Fe, 20.54 and Zn, 5.15 (mg/kg ww). The values for the female fish were determined to be Hg, 0.14; Cd, 0.03; As, 0.85; Pb, <0.52; Cu, 3.75; Fe, 21.82 and Zn, 8.11 (mg/kg ww). In terms of gender, the mean trace elements in the muscle tissue of male and female did not significantly vary (p < 0.05) except Cd and Zn. The results show that, according to European legislation, the muscle tissues of SJT are generally “safe” for human consumption.