Depleted uranium assessment and natural radioactivity monitoring in North West of Iraq over a decade since the last Gulf War

Abstract

For the sake of completeness of the surveillance process concerning the spread of depleted uranium (DU) in the Arabian Gulf region, we have applied a simple gamma spectroscopy technique to evaluate its content in Al Jolan, Nazzal and Askari districts in Al Fallujah area, Iraq for the first time and after more than one decade. The measurements were carried out along the lines of the wars that have been witnessed in Iraq last period and expected to be the region of impact of residuals of a large quantity of DU. The observed radionuclides are ⁴ K and other naturally occurring radioactive members of uranium and thorium series. The obtained results show that, the average specific activity concentrations of ²²⁶Ra, ²³²Th, ⁴ K, ²¹⁰Pb ²³⁸U and ²³⁵U in different soil samples collected from Al Fallujah area, Iraq in range of 20.09 ± 4.0 to 21.94 ± 2.4, 11.51 ± 2.3 to 11.75 ± 3.2, 96.53 ± 8.0 to 112.13 ± 49.8, 19.98 ± 4.6 to 20.76 ± 4.8, 25.4 ± 3.9 to 26.1 ± 6.0 and 1.28 ± 0.18 to 1.34 ± 0.21 respectively. The obtained values of Ra_eq for all the investigated samples are less than the recommended limit of 370 Bq kg^-1 and those for H_ex are less than one. These results have been compared with the previous works and the world mean values specified by the UNSCEAR reports. The mean ratio of ²³⁸U/²³⁵U activity in all cases is about the natural value (21.73) which is less than its value in case of DU (76.92). The present obtained results of DU levels show that although a large amount of DU was released in Iraq during the Gulf wars, the tested samples are DU free. This may be attributed to the reduction of DU from the soil surface by wind or sandstorms and the downward leaching process.

Keywords: Depleted uranium; High-purity germanium (HPGe) detector; Iraq; Natural radioactivity; Radionuclides.