Lind O C, Salbu B, Skipperud L, Janssens K, Jaroszewicz J, De Nolf W
Department of Plant and Environmental Sciences, Norwegian University of Life Sciences, As, Norway.
J Environ Radioact. 2009 Apr;100(4):301-7. doi: 10.1016/j.jenvrad.2008.12.018. Epub 2009 Feb 11.
A combination of synchrotron radiation based X-ray microscopic techniques (mu-XRF, mu-XANES, mu-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO(3).2.25H(2)O), dehydrated schoepite (UO(3).0.75H(2)O) and metaschoepite (UO(3).2.0H(2)O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 +/- 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (20-30%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO(2), UC and metallic U or U-Ti alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO(2,34) phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (73-96%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible.
基于同步辐射的X射线显微技术（微X射线荧光光谱法、微X射线吸收近边结构谱法、微X射线衍射法）相结合，应用于单个贫铀（DU）颗粒，并开展了半批量浸出实验，以将DU颗粒的潜在生物可利用性与特定地点的颗粒特性联系起来。已对从科索沃和科威特不同地点采集的选定样品中分离出的单个颗粒测定了DU颗粒中U的氧化态和晶体形式，这些地点在1999年巴尔干冲突和1991年海湾战争期间受到DU弹药污染。此外，对被DU颗粒严重污染的小土壤或沙子样品进行了模拟胃肠液（0.16 M HCl）提取。2000年在科索沃土壤和2002年在科威特土壤中采集的DU颗粒的特性因释放情况以及在一定程度上因风化条件而有显著差异。在DU弹药储存设施火灾期间释放的大的、易碎的亮黄色DU颗粒中测定出氧化态U（+6），并鉴定出诸如水合铀矿（UO(3).2.25H(2)O）、脱水水合铀矿（UO(3).0.75H(2)O）和变水合铀矿（UO(3).2.0H(2)O）等晶相。正如预期的那样，这些DU颗粒在0.16 M HCl中迅速溶解（2小时后84 +/- 3%被提取），表明具有高度的潜在迁移性和生物可利用性。相比之下，对被未使用的DU穿甲弹腐蚀产生的DU颗粒或受冲击的DU弹药污染的样品进行的2小时提取似乎要慢得多（20 - 30%），因为铀的氧化程度较低（+4至+6）。在来自科索沃和科威特的受冲击DU颗粒中测定出诸如UO(2)、UC和金属U或U - Ti合金等晶相，而仅在来自科索沃的颗粒中测定出的UO(2,34)相可能反映了更具腐蚀性的环境。尽管结果基于数量有限的DU颗粒，但它们表明从类似来源（金属U穿甲弹）释放的DU颗粒的结构和可提取性将取决于释放情况（火灾、冲击）以及在一定程度上取决于环境条件。然而，所有调查样品中的大多数DU颗粒（73 - 96%）在一周后溶解于0.16 M HCl中，这表明大多数DU物质具有生物可及性。
