Sediments in rivers represent tanks of contaminants and one class of the most harmful pollutants are heavy metals because of their toxicity, bioaccumulation, persistence and the impact on the ecosystem and the human body. Heavy metals are released into the environment from natural sources and anthropogenic activities like industrial processes, traffic, agricultural activities and sewerage system etc. The aim of the present Thesis work has been to determine chemical parameters (i.e. heavy metal concentrations) in the Nestore River Basin and to distinguish the impact of natural sources from that of anthropogenic activities. The Nestore River basin in Umbria, Central Italy shows an admirable example of heavy metal pollution in space and time. Concentrations of metals in sediments are tracked during the four seasons in the year 2010 in ten different sampling locations. The choice of the sites has been made on the basis of previously made biological investigation. For example, station 1 (The Nestore River), station 9 (The Fersinone River) and station 10 (The Calvana River) are shown like ecologically uncontaminated are their values were taken as the reference values in calculations. Samples have been treated with a microwave acid digestion and heavy metal concentrations have been obtained with Inductively Coupled Plasma - Atomic Emission Spectroscopy. The values of metal concentrations have been then discussed with a statistical analysis, which included total average values seasonal trends, enrichment factor, Principal Component Analysis. In order to discriminate between natural and anthropogenic sources it has been possible to calculate baseline concentration which is defined as the 95% of the predicted ranges of metal concentration toward an average in a normal sample. This estimate represents a natural content of heavy metals without human impact and points the information about naturally present metals in a specific region.