An Integrated Approach in the Assessment of the Vlasina River System Pollution by Toxic Elements

Abstract

Increasing pollutant levels in surface water are a very important problem in developing countries. In Serbia, the largest rivers are transboundary rivers that cross the border already polluted. Taking this into account, evaluation of the distribution characteristics, ecological risk, and sources of toxic elements in river water and surface sediments in the watercourses of the Vlasina watershed is of great significance for the protection of water resources in Serbia. A total of 17 sediment and 18 water samples were collected and analyzed by Inductively Coupled Plasma—Optical Emission spectrometry (ICP-OES) and Inductively Coupled Plasma—Mass spectrometry (ICP-MS) to determine micro- and macroelements contents. The geo-accumulation index (I_geo) was applied to determine and classify the magnitude of toxic element pollution in this river sediment. The contents of the studied toxic elements were below water and sediment quality guidelines. For studied river water, results of principal component analysis (PCA) indicated the difference in behavior of Cr, Mn, Ni, Cu, and As and V, respectively. Cluster analysis (CA) classified water samples according to As and Cu content. The PCA results revealed that lead in river sediments had different behavior than other elements and can be associated mainly with anthropogenic sources. According to the degree of I_geo, the majority of sediments in the Vlasina region were uncontaminated regarding studied toxic elements. The origin of elements is mostly from natural processes such as soil and rock weathering.