ESTUDIO COMPARATIVO SOBRE LOS NIVELES DE METALES PESADOS EN ALMEJAS (Muliniaspp.) EN CONSERVA Y EN FRESCO COMERCIALIZADAS EN GALICIA COMPARATIVE STUDY OF HEAVY METAL LEVELS IN TINNED AND FRESH CLAMS (Muliniaspp.) COMMERCIALIZED IN GALICIA ESTUDIO COMPARATIVO DOS NIVÉIS DE METAIS PESADOS EN AMEIXAS (Muliniaspp.) EN CONSERVA E EN FRESCO COMERCIALIZADAS EN GALIZA

Abstract

Molluscs, due to their filtrant capacity, can accumulate metals arriving to contaminate the foods and as consequence they can have a negative repercussion on the health of the consumers. In this study the content of some metals (Cu, Zn, Cd and Pb) in clam samples commercialized in Galicia (NW Spain), in tinned products as well as in fresh products, has been determined. For the analysis an anodic stripping voltammetry technique has been employed in order to obtain the metal levels in muscle and liver. Results have been statistically treated in order to evaluate the correlations between heavy metal content into the different established portions. It's interesting to emphasize the higher concentrations in liver that in muscle for zinc, lead and copper in fresh samples. Thus, the maximum values in fresh clam liver were for Zn: 1246.20 mg/kg; for Pb: 15.60 mg/kg and for Cu: 75.04 mg/kg, set against the maximum values of Zn (60.36 mg/kg), Pb (0.67 mg/kg) and Cu (9.48 mg/kg), in muscle. With respect to cadmium, in general, tinned products presented higher concentrations than the fresh ones, reaching one of them till 8.11 mg/kg, in the liver. Taking into account the importance of these molluscs in food and according to the outstanding legislation, it has been able to establish, from the toxicological point of view, that metal levels do not constitute a risk for human health.