Hydrochemistry and pollution probability of selected sites along the Euphrates River, Western Iraq

The hydrochemistry of Euphrates River in the study area which extended from Hit to Al-Saqlawia was studied in order to determine the physical, chemical, and biological properties in addition to the radiation level. Thirty-one stations along the Euphrates River were chosen, 17 of them represented the Euphrates River itself, whereas the other stations are considered as point pollution sources which all empty their load directly in the Euphrates River with an average total discharge of 32 m³/s. Twenty-eight samples of the Euphrates water of both high- and low-flow periods were analyzed for cations (Ca²⁺, Mg²⁺, Na⁺, and K⁺), anions (SO ₄ ⁼ , Cl^?, CO ₃ ⁼ , HCO ₃ ^? , NO ₃ ^? , PO ₄ ^?3 ), H₂S boron, dissolved oxygen, biological oxygen demand, bacteriological tests, radiation levels in addition to physical parameters such as hydrogen number (pH), total dissolved solid, electrical conductivity, total suspended solid, and temperature. This study showed that the cations and anions during periods of high and low flows are within acceptable limit with exceptional Cl^?. Hydrochemical formula during the high flow was Na-Ca-Mg-Cl-SO₄, then it changed into Na-Ca-Mg-HCO3-SO₄-Cl during the low-flow period. The average output cations and anions at downstream (Saqlawiya area) was relatively higher than those of input at upstream (Hit area); this attributed to the natural and anthropogenic activities originated mainly from agricultural activity and population communities around the river. Radiation level for ²¹²Pb, ²¹⁴Pb, ⁴⁰k, ²²⁰Ac, and ²¹⁴Bi showed that the higher level of radiation is concentrated within sediment rather than in water, but the radiation in both is within acceptable limit.