Accumulation of lead, cadmium, copper, zinc, and iron in tissues of Sardinella aurita from two sites; El-Umoum Drain in El-Max Bay (EUD) and Eastern Harbour (EH), on the Mediterranean coast of Egypt, Alexandria district were investigated and compared with the reference site Alam El-Room (AER), 227 Km away to the west from Alexandria City. Metals concentrations follow the sequence Fe > Zn > Cu > Pb > Cd in almost all tissues of fish at all sites. Out of the metals investigated, Fe, Cu, and Cd metals tend to accumulate in liver tissues. Accumulation of Fe and Cd (mg kg-1 wet weight) recorded maximum values in liver of male (131.97 ± 13.08 and 1.34 ± 0.56) and female (205.10 ± 12.01 and 1.50 ± 0.54) from EUD site, respectively. While Cu showed maximum concentration in liver of male (53.58 ± 3.15) and female (65.03 ± 2.33) fish of EH site. Zinc had a tendency to accumulate in gonads. Gonads of male (100.47 ± 7.57) and female (111.21 ± 4.36) fish of EUD site had the highest level of Zn. Gills of male and female fish of EUD site showed the highest concentration of Pb (15.54 ± 4.79 and 22.11± 2.70, respectively). Significant difference was recorded for Cd, Cu, Zn, Pb, and Fe in liver, for Cu, Pb, Fe, and Zn in gonads and gills and for Pb, Fe, and Zn in muscles of EUD and EH fish compared to reference (AER) site. Females accumulated metals more than males. A significant difference among sexes for Zn and Pb were recorded in liver, gills and gonads and for Cu in liver and for Fe in all fish tissues in EUD and EH sites (p < 0.05). The levels of Cd and Pb in muscles of fish from both sites were above the permissible legal limits suggested by World Health Organization, Food and Agricultural Organizations for human consumption. Results showed the need for routine monitoring of marine species contamination to ensure public and environmental health.
Key words: Metals, Round sardine, Tissues accumulation, Sex-variation, Egypt coast.
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