Mercury, cadmium, lead, arsenic, copper and zinc concentrations in albacore, yellowfin tuna and bigeye tuna from the Atlantic Ocean

The concentrations of Hg, Cd, Pb, As, Cu and Zn were determined in 67 tuna samples from the Atlantic Ocean, in order to determine the concentrations present in different species and to evaluate possible risks for human health as a consequence of the consumption of these products. The maximum permissible levels of Hg, Cd and Pb in foodstuffs are established by Commission Regulations (EC) 466/2001 and 78/2005. The species studied were albacore (Thunnus alalunga), yellowfin tuna (Thunnus albacares) and bigeye tuna (Thunnus obesus). These three species showed differences in the metal concentrations analyzed. The maximum Hg concentrations obtained in albacore and yellowfin tuna samples were well below the limit established for human consumption (1.0 mg kg(-1) wet weight), but some bigeye tuna individuals exceeded this limit. In the case of the other regulated metals, the values were well below the limit. For these three species, Hg concentrations increased as the size of the individuals increased, but there was no clear relationship between concentrations and sizes for the rest of the elements studied.