Seasonal Variation of Heavy Metals, Uranium, and Thorium Concentration in Jordanian Dams Water

Abstract

Abstract: This work investigated the seasonal variation of heavy metal concentrations in the waters of Moujib, Wala, King Talal, Kufranjeh, and Tannour dams in Jordan. Samples were collected from each dam’s entrance, dam lake (reservoir), and exit. Samples were collected at the end of the rainfall season, when dams were almost full, and at the end of summer, when the water was at its lowest level. The study investigated the content of As, Cd, Cr, Hg, Mo, Ni, Pb, U, and Th elements. The results revealed that the concentrations of As, Cd, Cr, Hg, Mo, Ni, and Pb were less than the lowest detectable limit during both seasons. The Uranium average concentrations for the wet and dry seasons were 1541 and 1564 ppt, respectively, while the average concentrations of thorium for the wet and dry seasons were 7 and 119 ppt, respectively. These results are below the allowed values according to the Jordanian standard for drinking water and international guidelines. They are comparable with values reported in the literature. This work indicates that Jordanian dam water is free from heavy metals, and the content of U and Th is within accepted levels.