In Cauda Venenum Health Hazards of Nuclear Power
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in cauda venenum Health hazards of nuclear power nuclhaz20140611Qannexes 1 11 June 2014 © Storm in cauda venenum Health hazards of nuclear power ANNEXES Jan Willem Storm van Leeuwen, MSc Independent consultant member of the Nuclear Consulting Group [email protected] first publication: 22 November 2010 revision January 2014 nuclhaz20140611Qannexes 2 11 June 2014 Abstract This study starts with a physical assessment of the quantities of the radioactivity being generated and mobilied by the entire system of related industrial processes making civilian nuclear power possible. It assesses the actual and potential exposure of the public to human- made radioactivity, and it discusses empirical evidence of harmful health effects of these exposures. The biomedical effects of radionuclides in the human body are briefly discussed. Furthermore this study analyses the mechanisms which may cause the uncontrolled dispersion of very large amounts of radioactivity into the environment. The study explains some consequences of a basic law of nature (Second Law) for the health risks of nuclear power now and in the future. Misconceptions, uncertainties and unknowns of the nuclear safety issue are addressed. Risk enhancing factors are discussed, along with the consequences of the present economic paradigm for the health risks of nuclear power at this moment and in the future. The hazards of nuclear power just do not stop at the reactor: what happens and what will happen with the human-made radioactivity? In causa venenum. Acknowledgements The author would like to thank Ian Fairlie for reviewing the radiological part of this report and for his suggestions, Angelo Baracca for his suggestions, and Stephen Thomas and John Busby for their comments. The author notes that this report does not necessarily reflect their opinion. In cauda venenum A Latin phrase from ancient Rome, meaning: the poison is in the tail. Using the metaphor of a scorpion, this can be said of a story or development that proceeds gently, but turns vicious towards the end. nuclhaz20140611Qannexes 3 11 June 2014 Contents ANNEX A Radioactivity A.1 Radioactivity, some basics Isotopes Radioactive decay Ionizing radiation Half-life Nuclear bomb equivalents A.2 Nuclear radiation A.3 Radioactive materials Spent nuclear fuel Fission products Actinides and minor actinides Activation products A.4 Radioactive decay of human-made radioactivity A.5 Summary Annex A ANNEX B Tritium, carbon-14 and krypton-85 B.1 Introduction B.2 Tritium Hydrogen isotopes Anthropogenic tritium production Chemical properties DNA incorporation Health risks Removal and disposal of tritium B.3 Carbon-14 Carbon isotopes Anthropogenic carbon-14 production Chemical properties DNA incorporation Suess effect Health risks Removal and disposal B.4 Krypton-85 Anthropogenic krypton-85 production Chemical properties Biological properties Health risks Removal and disposal B.5 Summary Annex B References ANNEX C Uranium C.1 Uranium mining C.2 Mine reclamation C.3 Summary Annex C nuclhaz20140611Qannexes 4 11 June 2014 ANNEX D Reprocessing and nuclear safety D.1 Vital role of reprocessing in advanced nuclear concepts D.2 Reprocessing of spent fuel The process Reprocessing and the Second Law Complete separation is a fiction Costs D.3 Discharges from reprocessing plants D.4 Plutonium recycling Closed-cycle reactors Plutonium in LRW’s, MOX fuel No net energy from MOX Health hazards from MOX fuel D.5 Vitrification of radioactive waste Waste management concepts Vitrification Misconceptions and fallacies Conclusion D.6 Health hazards Routine discharges Proliferation of plutonium ‘Minor’ accidents Large accidents Dismantling D.6 Summary Annex D ANNEX E Partitioning & transmutation E.1 Concept and its promises Shifting focus E.2 Transmutation Fission of actinides E.3 The system E.4 Partitioning Outline Difficulties E.5 Fuel element and target fabrication E.6 Transmuters E.7 U and Pu in closed-cycle reactors Reprocessed uranium Plutonium E.8 Feasibility of P&T systems Timeframe Inherent flaws Technical imperfections Integration Energy balance Costs Human resources E.9 Health hazards Potential, direct risks nuclhaz20140611Qannexes 5 11 June 2014 Present, indirect risks E.10 Summary Technical features of P&T Radioactivity P&T and the Second Law Costs Risk assessment Energy balance Human resources E.11 Conclusions E.12 Summary Annex E References ANNEX F Thermodynamics, entropy and Second Law F.1 Thermodynamics System System boundaries F.2 Energy and the First Law Energy First Law F.3 Entropy Spontaneous changes Definition of entropy Entropy changes Entropy and chance F.4 Entropy and functionality F.5 Second Law Stochastic processes Second Law Two approaches Importance of the Second Law F.6 Consequences of the Second Law Ageing of materials and structures Separation and purification processes Mineral energy sources F.7 Observable entropy effects in the biosphere F.8 Summary Annex F ANNEX G Energy cliff and thermodynamic scarcity G.1 Energy cliff Dilution factor Recovery yield Energy cliff of uranium Fossil fuels G.2 Thermodynamic scarcity of mineral energy sources and minerals G.3 Summary Annex G References nuclhaz20140611Qannexes 6 11 June 2014 ANNEX H IAEA, ICRP and UNSCEAR H.1 IAEA H.2 H.3 H.4 Summary Annex H References nuclhaz20140611Qannexes 7 11 June 2014 ANNEX A Radioactivity A.1 Radioactivity, some basics Isotopes Atoms are composed of a nucleus with a positive electric charge surrounded by electrons with a negative charge. The negative charge equals the positive, so the atom is electrically neutral. The nucleus consists of protons (positive charge) and neutrons (neutral). The number of protons determines to which chemical element the atom belongs. The chemical properties of an atom are determined by the number of protons. The number of neutrons may vary; atoms with an equal number of protons but a different number of neutrons in the nucleus are called isotopes. The chemical properties of isotopes are identical. The nuclear-physical properties of an atom are partly determined by the number of neutrons. Some isotopes have an unstable nucleus. Radioactive decay Radioactivity is the phenomenon that unstable nuclei of atoms (radionuclides) spontaneously decays into another kind of atom, coupled with the emission of nuclear radiation: alpha, beta and/or gamma radiation. Alpha radiation consist of alpha (a) particles: helium-4 nuclei (2 protons + 2 neutrons) which are ejected from the decaying nucleus at very high speed. Beta radiation consist of beta (b) particles: electrons ejected from the nucleus at very high speed. Gamma radiation consists of gamma (g) rays, very energetic electromagnetic rays and much more penetrating than X-rays. The decay product, also called the decay daughter, can be radioactive in itself or can be stable. In nature on earth a few radioactive kinds of atoms occur in low concentrations. Important with respect to nuclear power are the elements uranium and thorium, which are formed billons of years ago in supernova explosions. These radionuclides decay via a series of other radionuclides into stable lead or bismuth atoms. During fission of uranium large amounts of radioactive isotopes of nearly all known elements are formed. β © Storm tritium atom β-emission helium-3 atom Figure A1. Radioactive decay of tritium.Tritium, symbols T, 3H or H-3, is a heavy isotope of hydrogen, with one proton and two neutrons in the nucleus. When a tritium atom decays, it emits a beta particle (an electron) at high speed. After decay the nucleus contains two protons and one neutron, the nucleus of a helium-3 atom, which captures a second electron and becomes a neutral helium-3 atom. The sums of electric charges remain constant and a minute fraction of the mass is converted into energy. nuclhaz20140611Qannexes 8 11 June 2014 Ionising radiation Nuclear radiation is often called ionising radiation, because it strongly interacts with matter forming ions. Ionising radiation is harmful to living organisms, for it destroys biomolecules. Alpha and beta radiation can be blocked by thick paper respectively aluminum foil, so these rays may seem not very harmful to man. However radionuclides radiating alpha or beta rays inside the human body are extremely dangerous, because the living cells are not protected by the skin or clothes. A dose of only a few nanograms of the alpha-emitter polonium-210 in the human body is lethal. A complicating factor is that alpha and beta radiation are not detectable by hand-held counters, which can only detect gamma rays. Radionuclides that emit weak or no gamma rays are invisible to these detectors. A number of biologically very active radionuclides fall within this category, such as tritium (radioactive hydrogen) and carbon-14 (radioactive carbon). Figure A2. Symbol of nuclear radiation. This pictogram symbolizes three kinds of lethal nuclear radiation: alpha (a), beta (b) and gamma (g) radiation. Half-life The rate of radioactive decay is characteristic to each kind of radionuclide and cannot be decelerated or accelerated by any means. Radioactivity cannot be destroyed nor made harmless to man and other living organisms. Radionuclides occurring in nature, such as uranium and thorium, have very long half-lifes measured in billions of years. These nuclides have been formed in stellar explosions long before the Earth came into being. Human-made radionuclides have much shorter half-lifes, ranging from seconds to millions of years. The specific radioactivity of a radionuclide (measured in becquerel per gram, Bq/g) is higher as the half-life is shorter. Storm © time t = 0 after 1 half-life after 2 half-lifes Figure A3. Decay of a radionuclide. One half-life period after creating of a given amount of a certain radionuclide at time t = 0, half of the radionuclides has decayed into another kind of nuclide, called the daughter nuclide. In most cases the decay doaughter is a non-radioactive, stable nuclides. During the next half-life period half of the remaining radionuclides decay, and so on.