Redução do teor de contaminantes químicos em bivalves provenientes do Estuário do Tejo

Mestrado em Engenharia Alimentar - Instituto Superior de AgronomiaManila clam (Ruditapes philippinarum), mussel (Mytilus sp.) and peppery furrow shell clam (Scrobicularia plana) are species with high abundance in the Tagus estuary. However, these species may have high levels of contaminant metals. This study aimed to determine the effect of depuration of manila clam, mussel and peppery furrow shell clam on the content of contaminant metals (Cd, Pb and Hg) and on macro, micro and trace elements (S, Ca, K, Cl, Fe, Cu, Zn, As, Se, Br, Rb and Sr). The results revealed that the depuration was effective in reducing the levels of Pb in peppery furrow shell clam and Manila clam. In the mussel no decrease was registered in this contaminant. During the depuration no decreases were registered in Hg and Cd. Mussel and peppery furrow shell clam condition decreased through the depuration, as indicated the glycogen content in the adductor muscle of these bivalves. In peppery furrow shell clam the mortality rate reached 11 %. Manila clam proved to be the most adaptive to depuration conditions. The depuration also decreased the excess of Fe in Manila clam and peppery furrow shell clam, whose levels were above the tolerable upper limit (UL). In the mussel this decrease resulted in a disadvantageous loss of this minera