Study of the Effect of Irrigation with Urban Wastewater on the Concentration of Heavy Metals in Surface Soils of the Southern Parts of Harsin, Kermanshah

In the present work heavy metal contamination of soil in Harsin city and its-Kermanshah was investigated. 37 soil samples were collected from two depths 0-20 and 20-40 cm from cultivated lands in southern area of Harsin city. 15 and 22 sampling stations are located in irrigated fields with sewage and fields without sewage, respectively. Also, soil texture, percentage of gravel, silt and clay components were determined by hydrometric method. Total concentration and bioavailable detection of heavy metals: chromium, manganese, iron, cobalt, copper, zinc, cadmium, lead and arsenic, in soil samples were determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES) method. results showed that the total content of heavy metals in soil were significantly different in the two sampling depths. Wastewater irrigation on soil properties and the amount of total and soluble heavy metals is affective. According to the statistical analysis, two irrigation factors with sewage and geochemistry of the study area were identified as essential factors on the increasing amount of heavy metals.