Review of the toxic trace elements arsenic, cadmium, lead and mercury in seafood species from Algeria and contiguous waters in the Southwestern Mediterranean Sea.

Abstract

An assessment is made of published data on concentrations of four toxic trace elements arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and methyl mercury (MeHg) in seafood species from Algerian coastal waters. The data relate mainly to fish and mollusks, with Pb and Cd being the most studied elements. In contrast, no studies were found for As and MeHg in mollusks and crustaceans, and none for total Hg in crustaceans. Data analysis has shown that the element concentrations depend on the element analyzed, in particular its chemical form, and they vary with the species studied and the area where the organisms were sampled. As concentrations in muscle of sardine (Sardina pilchardus) from the eastern zone (Bejaia) (2.98mgkg-1 wet weight), Pb in muscle of tuna (Euthynnus alletteratus) (0.49mgkg-1 wet weight) from the western region (Mostaganem) and in muscle tissue of the mussel (Mytilus galloprovincialis) (10.67mgkg-1 dry weight) from Oran all exceed the threshold risk limits set by national and international regulations. Given these findings, to guarantee seafood safety for the Algerian consumer, it is recommended to carry out monitoring of these trace elements in seafood species caught along the Algerian coast, particularly the most consumed fish, i.e., sardines, and predators such as swordfish and tuna which can accumulate high concentrations of toxic metals, particularly Hg. Obtaining a regional assessment based on similar analyses from Tunisia and Morocco was severely hampered since few similar species or taxonomic groups were analyzed in all three countries.