Radionuclides content and the radiological hazard of sediment of the Euphrates River and sprigs-western Iraq

Abstract

Sediments samples from ten stations along the Euphrates River and seven
samples from selected springs within Al –Anbar governorate, (western part of Iraq),
were collected and analyzed for radioactivity. Sediments samples were dried at 100
ºC for 24 hours. Radioactivity in 1 kg of each sample was measured using gamma
spectrometer system based on a pure germanium detector with efficiency 30%. The
activity of Ra-226, Th-232, K-40 were measured to be within the typical average of
the radioactivity in sediment in world rivers, while relatively elevated concentration
were found in the sediment of some of the studied spring. In current study activity
concentrations of Cs-137 in the sediments were detected which may be caused by
the global fallout as well as caused by transferring of cesium from the relatively high
concentration areas in western desert by the rainwater within the valleys to the
sediments of the Euphrates. The radiological aspects were investigated by
calculating the radiological hazard indices such as absorbed dose rate, annual
effective dose equivalent, hazard indices and gamma index. The radiological hazard
indices were below the recommended international values. Ra-226 and Cs-137
concentrations in water and radiation doses due to drink water of the Euphrates
River were estimated. The maximum estimated interior doses which caused by 137Cs
and 226Ra in water were found to be 1.93 x 10-5mSv/y and 4.01x10-3mSv/y,
respectively.