The aim of the present thesis work is to develop methodologies for determining biomarkers in specific food products to evaluate either their traceability, e.g, cured ham, or their role at the environmental observatory, e.g, sea mollusk (oysters and mussels ) as pollution indicators. A set of methodological guidelines based on the speciation of some elements identified as key differential for the indicated samples have been developed. Particular attention has been paid to the methodologies nature based on the direct observation of the target samples. In this concern, methodologies have been developed including the application of Hyperspectral Imaging (HSI), XANES (Synchrotron) and Isotope Dilution to a successful characterization of the samples. For the cured ham, the main results obtained, include the development of a classification model by PLS-DA for the spectra obtained by HSI. The PLS-DA is constituted by two factors 86% and 90% respectively. Predicting values were obtained in the range of 0.70 to 1.30 for Iberian ham and a 1.70 to 2.30 for Italian ham, the regression statistics showed an RMSEC of 0.114, an RMSECV of 0.116 and r2 from the CV of 0.947, so they can be differentiated by their origin To search for specific chemical biomarkers of cured ham traceability, speciation of Fe and Zn was performed using XANES synchrotron technique in samples of different curing times. For iron, speciation was based in the oxidation states Fe+2 and Fe+3. For Fe+2, no organic species were identified, but inorganic species of similar structure to (Fe (NH4)2(SO4)2) where Fe interact to an S and N atom were found. This compound could be explained from the proteolysis process, because its contribution to the sample spectra decreases when curing time increases. For Fe +3 the majority inorganic species was found to be similar to FeCl3, where its contribution at the beginning of the curing process (03-14 months) presented important differences in different parts of the ham, observing the major contribution in the outer region of the ham samples. For the rest of curing times (26 to 40 months) no differences were observed between inner and outer region. In addition, the organic species identified for Fe+3 were porphyrin compounds (myoglobin and hemin) being myoglobin the major compound found. In this sense, it has been demonstrated that the identification of Fe species is a good methodology in order to establish the traceability of the curing process for dry-cured ham. In the case of Zn, the speciation was based on the nature of organic and inorganic species, but the contribution of the species did not present any change throughout the different curing time samples, thus any change in the contribution of the specie can be attributed to external factors other than the curing process. On the other hand, by the Isotopic Dilution analysis it was possible to differentiate between the origin of the dry-cured ham, such as Iberian, Italian and Portuguese ham. Each region is isotopically different from the rest, thus this study provides geographical interaction and information for each region, where the pigs are obtained from for the production of cured hams. Concerning mollusks, speciation of As and Zn were considered due to the toxicity of their species (As) and the risk of bioaccumulation (Zn). Speciation was carried out using XANES synchrotron technique. In the case of As, arsenobetaine was the main species of Arsenio-compounds found in the samples analyzed, which ranged from 70% to 96% of the total arsenic. In the case of Zn, more than 50%, of the contributions of the Zn-species were attributed to metallothioneins, demonstrating that Zn is attached to the sulfur atom from the breakdown of amino acids and not from inorganic Sulphur moieties. Finally, one of the principal outputs of the mollusks research has been the production of a reference material for the environmental monitoring of sea coasts, obtained from a sampling location of the mollusk analyzed in the present work and as result of the analysis performed. The final characterization of such reference material is still in progress.