University of Tehran/Springer International Journal of Environmental Research 1735-6865 9 1 2015 01 01 An IndexApproach toMetallic Pollution in RiverWaters 385 394 910 10.22059/ijer.2015.910 EN T. Nasrabadi Assistant professor, Graduate faculty of environment, University of Tehran, Iran Journal Article 2014 12 31 Twenty water samples from a river system in southern Caspian Sea basin were<br />collected and analyzed for physicochemical parameters and metals (Cu, Zn, As, Cd, Pb, Ni and<br />Mn). In order to evaluate the risk potential of metal pollution in river water, use of two indices<br />namely heavy metal pollution index (HPI) and contamination index (Cd) accompanied by cluster<br />analysis was taken in to consideration. Stations located within the upstream of the river (1 to 13)<br />seemed to encounter low risk potentials while the downstream stations (14 to 20) approved to<br />hold higher risks.The results also showed relativelymeaningful correlation among different metals<br />which may be attributed to their same entry source, mainlymining and quarrying activities in the<br />central parts of the basin following bymunicipal and industrial wastewater discharge to the river<br />in downstream. The convergence of both indices in this study was also of interest. Although the<br />mean values of both indices were below the critical values, severe precautions must be taken into<br />consideration especially in the stations holding high risk potentials. Extreme use of river water<br />for drinking, agriculture and industrial purposes within the water basin, relatively biota-rich<br />characteristic of the river and Caspian Sea as the final sink of the river are among the most significant<br />reasons that make the river monitoring implementation inevitable. https://ijer.ut.ac.ir/article_910_ccf5f5452c058f1b07f736bb335b3f11.pdf