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Uranium Transport in the Sub-Surface Environment Koongarra - A Case Study
Published in Herbert E. Allen, E. Michael Perdue, David S. Brown, Metals in Groundwater, 2020
Uranium-238, the chief constituent of natural uranium (99.27% abundance) decays via alpha particle emission with a half-life of 4.468 × 109 years to the relatively short-lived 234Th (t½ = 24.1 days). Thorium-234 then decays via (3 emission to 234Pa which in turn decays by β emission (with half-life of 6.7 hours) to the longer-lived 234U (t½ = 2.48 × 105 years). This beta stable, alpha-emitter then decays to 230Th. Thorium-230, with a half-life of 7.52 × 104 years, is relatively stable decaying to 226Ra (t½ = 1602 y) and finally to 206Pb via a number of other relatively short-lived intermediates (including 222Rn and 210Pb).
Development of Regulations for Radionuclides in Drinking Water
Published in Barbara Graves, Radon, Radium, and Other Radioactivity in Ground Water, 2020
The primary chemical toxic effect of natural uranium is on the kidneys. This has been seen from evidence for over a century from both medical administration to humans and numerous animal studies. Nephritis (inflammation of the kidneys) and changes in urine consumption are clear symptoms. Based on this evidence, the Adjusted Acceptable Daily Intake for uranium is 60 micrograms per liter and is computed by allocation of the Acceptable Daily Intake for a 70-kg adult consuming two liters of water per day. This level is roughly equivalent to 40 pCi/L.
National Primary Drinking Water Regulations for Radionuclides
Published in Edward J. Calabrese, Charles E. Gilbert, Harris Pastides, Safe Drinking Water Act, 2017
As evidenced by over a century of data from both medical administration to humans as well as from numerous animal studies, the primary chemical toxic effect of natural uranium is on the kidneys. Nephritis (inflammation of the kidneys) and polyuria (excessive urine excretion) are clear symptoms. It is estimated by EPA that health effects to the kidney are of the same order of magnitude as radiotoxic effects to bone.
Research on risk management and control strategy of uranium resource procurement in China
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Xiaopeng Guo, Xinyue Zhang, Dongfang Ren, Kai Lin
At present, there are two main modes of uranium supply in the world: the first one is the supply of natural uranium, specifically refers to the uranium that has been preliminarily processed after mining; the second one is the supply of enriched uranium, specifically refers to the uranium that has been refined and produced, including the dilution of highly enriched uranium and the uranium extracted from spent fuel recovery (Brutschin, Cherp, and Jewell 2021; Massot and Chen 2013). With the development of nuclear power industry in the world, the global demand for uranium resources continues to grow. In terms of the uranium reserves in major countries, the world’s reserves of uranium resources in 2019 was 608.96 × 104 tons, with Australia, Kazakhstan, and Canada ranking the top three, accounting for 27.8%, 14.9% and 9.3% respectively. China’s uranium reserve is 24.89 × 104tons, accounting for 4.1%, ranking ninth (WNA 2022d), as shown in Figure 2.
Transient System Thermal-Hydraulic Assessment of Advanced Uranium- and Thorium-Based Fuel Bundle Concepts for Potential Use in Pressure Tube Heavy Water Reactors—I: Two-Channel Analyses
Published in Nuclear Technology, 2021
S. Wang, T. Beuthe, X. Huang, A. Nava Dominguez, A. V. Colton, B. P. Bromley
Natural uranium (NU) is the main fuel used currently in conventional pressure tube heavy water reactors (PT-HWRs). Thorium, as an alternative fertile nuclear fuel, is far more abundant in the earth’s crust.1 PT-HWRs such as the CANada Deuterium Uranium (CANDU) reactor (see Figs. 1 and 2) feature a unique design that makes them well suited to use advanced uranium-based and thorium-based fuels.2,3 PT-HWRs utilize compact, self-contained fuel bundles and are able to reposition these bundles in the reactor while operating at full power. The excellent neutron economy of PT-HWRs through the use of heavy water as moderator and as coolant, as well as the ability to carry out online refueling, provides PT-HWRs with a high degree of operational flexibility with regard to alternative fuel concepts. Therefore, it is possible to consider the use of a variety of advanced uranium-based and thorium-based fuel concepts for potential use in existing PT-HWRs including CANDU reactors.4 The use of advanced fuels could help extend nuclear fuel resources while also achieving improvements in operational safety margins in PT-HWRs.
Surveillance results and bone effects in the Gulf War depleted uranium-exposed cohort
Published in Journal of Toxicology and Environmental Health, Part A, 2018
Melissa A McDiarmid, Marianne Cloeren, Joanna M Gaitens, Stella Hines, Elizabeth Streeten, Richard J. Breyer, Clayton H. Brown, Marian Condon, Tracy Roth, Marc Oliver, Lawrence Brown, Moira Dux, Michael R. Lewin-Smith, Frederick Strathmann, Maria A. Velez-Quinones, Patricia Gucer
Natural uranium is a high-density, alpha-emitting radio-active actinide series metal comprised of three isotopes, U234, U235 and U238 and which also possesses chemically toxic properties (Agency for Toxic Substances and Disease Registry (ATSDR) 2018). DU, a man-made by-product of the U-enrichment process wherein much of its U234 and U235 are removed, retains approximately 60% of natural U’s specific (radio) activity, but all of its chemical toxicity (Army Environmental Policy Institute 1995). The chemical, metal properties of DU have been exploited for armor-piercing capabilities in military applications (ATSDR 2018; Army Environmental Policy Institute 1995; Squibb, Leggett, and McDiarmid 2005).