Characterisation of DU Particles from Kosovo and Kuwait

Abstract

Large amounts of DU material has been released to the environment in Kosovo and Kuwait due to the use of depleted uranium (DU) ammunition during the 1991 Gulf war and the 1999 Balkan conflict. Following the impact of metallic DU penetrators on solid targets, DU particles are dispersed and ignited, and uranium in the particles is oxidized. Following inhalation or ingestion of DU particles, the amount of DU that is absorbed into the blood and distributed to tissues and organs will largely depend on the particle size distribution and associated weathering rates (solubility) both in the respiratory system as well as the GI tract. Particle weathering rates are related to particle characteristics such as specific surface area, size distribution, elemental composition, U oxidation states and crystallographic structure.In order to improve the basis for health impact assessments related to contamination of DU in Ceja Mountains, Kosovo and Al Doha, Um Al Kwaty as well as Manageesh Oil fields in Kuwait, DU particles originating from these sites have been isolated and characterised in detail using advanced analytical techniques. Information on particle size, surface structure and surface elemental distribution were obtained by means of electron microscopy, whereas elemental distribution, oxidation state and crystallographic structure of U were determined using synchrotron radiation (SR) based x-ray microscopic techniques. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Accelerator Mass Spectrometry (AMS) were employed to obtain U isotope ratios for source identification purposes.Characteristics of DU particles in soil/sand from Kosovo and Kuwait contaminated during the Balkan conflict and Gulf war varied significantly depending on the release scenario. Atom ratios ( 236 U/ 235 U) obtained from ICP-MS and AMS varied between individual particles, but demonstrated that U in the DU-particles originated from reprocessed fuel. The bright yellow, highly oxidised DU particles associated with a fire in a DU ammunition storage facility showed a wide particle size distribution; from submicron to several O.C. LIND ET AL. 58 hundred micrometers. Furthermore, the micro-XRD signals closely resembled those of schoepite, dehydrated schoepite and metaschoepite. DU in sand samples contaminated with these particles is expected to dissolve quite rapidly in biological fluids. In contrast, the potential mobility of smaller and less oxidised DU particles, originating from the corrosion of DU penetrators or collected in tanks hit by DU ammunition should be significantly lower. The presence of respiratory DU particles where U is more oxidised than UO 2 , and exhibiting high weathering rates, reflects that DU particles are potentially more bioavailable than natural uranium. Thus, environmental or health impact assessments for areas affected by DU ammunitions should take into account oxidation states, their corresponding weathering rates and the subsequent mobilisation of U from oxidized DU particles.

Characterization of U/Pu particles originating from the nuclear weapon accidents at Palomares, Spain, 1966 and Thule, Greenland, 1968

“…(nuclear fuel partially burned) caused the dispersion of particles containing Pu and U (Lind et al, 2004;Jiménez-Ramos et al, 2006) over a terrestrial area of about 2.3 km 2 (Iranzo et al, 1987) situated close to the Mediterranean. A similar accident occurred at Thule, Greenland, 1968, where a B-52 bomber carrying four thermonuclear bombs caught fire and crashed on the ice at Bylot Sound.…”

Production and Characterization of Monodisperse Plutonium, Uranium, and Mixed Uranium−Plutonium Particles for Nuclear Safeguard Applications

“…These methods are also applied in the area of nuclear forensics to detect and prevent the illicit trafficking of nuclear material, , as well as for monitoring and risk assessment of radioactively polluted sites. In the latter case, particle analysis has been introduced and used during the past decade as it has been shown that most of the activity released is carried by particles. − These studies underline the importance of characterizing particulate effluents as the impacts on health and the environment ultimately depend on the chemical and physical composition of the particles.…”

Actinide Colloids and Particles of Environmental Concern

“…In general, radionuclide composition, activity concentration, isotope ratios, and burn-up will reflect the emitting source of released particles, while particle characteristics such as size distribution, crystallographic structure, and oxidation state ultimately depend on their release scenarios (i.e., affected by temperature and pressure, presence of air) and histories . Volatility of the released material as well as particle characteristics are determinant in “hot” particle ecosystem behavior …”

“…Actinide containing particles from military use span a size range from submicrometer to several hundred micrometers . Pure An or AnO x particles (An = Pu,U) and mixtures thereof have been reported.…”

“…More than 50% of the particles were smaller than 1.5 μm, making them potentially harmful to human health because they can be dissolved or resuspended (cf., section 5). Lind et al determined oxidation state distribution (mean oxidation state of uranium DU particles), indicating strong influence on weathering.…”