Arab Journal of Nuclear Sciences and Applications, 45 (2) 210-217 (2012) -210- Investigation of depleted uranium contamination in the south parts of Qatar using Gamma ray spectroscopy and ICP-MS A. T. Al-Kinani*, M. A. Amr**, K. A. M. Al-Saad**, A. I. Helal***, and M. Al Dosari* *Radiation and Chemical protection Department, Ministry of Environment, P. O. Box 7634, Doha, Qatar. **Department of Chemistry and Earth Sciences, Qatar University, P. O. Box 2713, Doha, Qatar. ***Department of Nuclear Physics, NRC, Atomic Energy Authority, Cairo, 13759, Egypt. ABSTRACT Before and during the second Gulf War training of the international forces in the Gulf region, depleted uranium (DU) emanations used in southern parts of Iraq and northern part of Kuwait and Saudi Arabia led to the contamination of the region with DU. Because of the possibility of creeping of DU particles to the south of Qatar. Twenty one samples of soil were collected from the south of Qatar, near Saudi borders. The samples were analyzed by two method, inductively coupled plasma mass spectrometry (ICP-MS) and Gamma ray spectroscopy. Since the isotopic abundance of uranium in DU is different than that in nature, the only evidence of DU contamination is the disruption of the natural isotopic abundance i,e 235 U/ /238 U. The measurement shows that the region is not contaminated with depleted uranium since the 235 U/ /238 U ratio is nearly 0.00709 which is the ratio for natural uranium. Gamma ray spectroscopy methods are well known analytical methods for the determination of most long-lived radionuclides in environmental samples. ICP-MS technique is very sensitive, accurate, rapid and low cost techniques for the determination low level of many long-lived radionuclides. Also it requires only small amount of sample (< 10 g) for the analysis. Its detection limit is comparable to the Gamma ray spectroscopy methods and it has rapid analytical capacity. However, no single analytical technique can be better than other. Each technique has its own strengths and weaknesses. In general, ICP-MS techniques are good complementary to the Gamma ray spectroscopy techniques for the determination of most of long-lived radionuclides. The results of ICP-MS were nearly the same, but more accurate than the method of gamma ray spectroscopy. The ICP-MS method was not affected by the sampling, calibration and statistical error. Key Words: Depleted Uranium /Gamma Ray Spectroscopy/ ICP-MS . INTRODUCTION Depleted Uranium (DU) is a by-product obtained from Uranium enrichment to produce fuel for nuclear reactors and atomic bombs. It is distinguished from natural Uranium by differing the Uranium isotopic ratios. Natural Uranium contains 99.27% of U-238, 0.72% of U-235 and 0.0055% of U-234. Thus, the ratio ( 235 U/ 238 U) in natural Uranium = 0.0073. Depleted Uranium contain 99.797% of U-238, 0.202% of U-235 and 0.0008% of U-234. Depleted Uranium (DU) is a low cost material that is readily available. It has high density (19.05 g /cm 3 ), which is 2.54 more than that for Iron. Depleted Uranium is used in application where its combination of high density, fabricability, relatively good mechanical properties and availability give it an advantage over other materials. The main civilian uses of DU include counter- weights in aircraft, shielding, and sinker bars. The United States Armed Forces have used DU in the manufacture of munitions, armor, and armor piercing projectiles. Depleted uranium has several military