Assessment of Heavy Metal Pollution in Sirwan River by Heavy Metal Pollution Index (HPI) and Metal Index (MI)

The study aims to evaluate the quality of Sirwan River water based on its heavy metal contents by using two of the most recent indexes regarding heavy metals which are the heavy metal pollution index (HPI) and the metal index (MI). In this term, twenty-four sampling stations were selected along with the Sirwan River from downstream of Darbandikhan Dam to the border of Jalawlaa Sub-district. Seven heavy metals including aluminum (Al), iron (Fe), zinc (Zn), cadmium (Cd), lead (Pb), nickel (Ni), and chromium (Cr) were analyzed by using an inductively coupled plasma spectrometer (ICP). The average value of the HPI index was found to be 47.2 and 12.8 for drinking and irrigation uses, respectively, which indicates that water in Sirwan River is seriously polluted for drinking purposes, while it falls under the pure class for irrigation uses. Also, the results of MI for domestic and irrigation uses were seen to be 5.7, which falls under the seriously affected class, and 0.65 under the pure class, respectively. The study revealed the effect of man-made sources on the pollution load of Sirwan River water.