Evaluation of water quality using heavy metal index and multivariate statistical analysis in Lorestan province,Iran

In the present study, the water quality of Silakhor River, located in Rahim Abad hydrometric station, was analyzed based on Boron, Iron, Nickel, Fluorine, Manganese, Chromium, Cadmium, Aluminum, Copper, Zinc and Lead pollution. The samples were collected from Silakhor River in Rahim Abad hydrometric station during a one-year period, from December 2012 to November 2013. In addition, metal index (MI) and heavy metal evaluation index (HEI) were applied to evaluate the amount of heavy metal pollution of water resources in the study area. The aforemention indices determined the origin of contamination of water resources, drinking or non-drinking. The findings from the samples showed that the amount of some heavy metals, such as Lead, Chromium, Cadmium and Manganese was higher than permissible limit of WHO standard. However, metal index (MI) and heavy metal evaluation index (HEI) proved that all samples are non-potable. In the present study, statistical studies (correlation coefficient, factor analysis and cluster analysis) were employed to determine the probable origin of the area’s elements. The findings indicated a multiple source of pollutants for the region water resources including two major sources; one is associated with the region lithology (the natural factor) while the other is caused by human activity in the region (anthropogenic factors).