Polonium-210
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Radiation Risk Assessment
PS008-1 RISK ASSESSMENT POSITION STATEMENT OF THE HEALTH PHYSICS SOCIETY* Adopted: July 1993 Revised: April 1995 Contact: Brett Burk Executive Secretary Health Physics Society Telephone: 703-790-1745 Fax: 703-790-2672 Email: [email protected] http://www.hps.org Risk assessment is the process of describing and characterizing the nature and magnitude of a particular risk and includes gathering, assembling, and analyzing information on the risk. Risk assessment is a foundation of risk management and risk communication. In order to effectively manage risks and to communicate risks to the public, a clear understanding of the nature and magnitude of the risk at relevant exposure levels is necessary. The Health Physics Society has become increasingly concerned with the erratic application of risk assessment in the establishment of radiation protection regulations. These regulations are inconsistent, poorly coordinated among federal agencies, and inadequately communicated to the public. Examples of problem areas include (1) 100- to 1,000-fold discrepancies in permissible exposure levels among various regulations, all allegedly based on the same scientific risk-assessment data, and (2) proposed expenditures of billions of federal and private dollars to clean up radioactively contaminated federal and commercial sites without careful consideration of the actual public health benefits to be achieved. The Health Physics Society recognizes that there are many questions and uncertainties associated with the risk-assessment process and that data may be incomplete or missing. Accordingly, limitations in risk assessment must be fully recognized and made explicit in establishing regulations for the protection of the public health. The Health Physics Society supports risk assessments that are consistent, of high technical quality, unbiased, and based on sound, objective science. -
Chapter 1.2: Transformation Kinetics
Chapter 1: Radioactivity Chapter 1.2: Transformation Kinetics 200 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity http://www.world‐nuclear.org/info/inf30.html 201 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity Serial Transformation In many situations, the parent nuclides produce one or more radioactive offsprings in a chain. In such cases, it is important to consider the radioactivity from both the parent and the daughter nuclides as a function of time. • Due to their short half lives, 90Kr and 90Rb will be completely transformed, results in a rapid building up of 90Sr. • 90Y has a much shorter half‐life compared to 90Sr. After a certain period of time, the instantaneous amount of 90Sr transformed per unit time will be equal to that of 90Y. •Inthiscase,90Y is said to be in a secular equilibrium. 202 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity Exponential DecayTransformation Kinetics • Different isotopes are characterized by their different rate of transformation (decay). • The activity of a pure radionuclide decreases exponentially with time. For a given sample, the number of decays within a unit time window around a given time t is a Poisson random variable, whose expectation is given by t Q Q0e •Thedecayconstant is the probability of a nucleus of the isotope undergoing a decay within a unit period of time. 203 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity Why Exponential Decay? The decay rate, A, is given by Separate variables in above equation, we have The decay constant is the probability of a nucleus of the isotope undergoing a decay within a unit period of time. -
Radiation Risk in Perspective
PS010-1 RADIATION RISK IN PERSPECTIVE POSITION STATEMENT OF THE HEALTH HEALTH PHYSICS SOCIETY* PHYSICS SOCIETY Adopted: January 1996 Revised: August 2004 Contact: Richard J. Burk, Jr. Executive Secretary Health Physics Society Telephone: 703-790-1745 Fax: 703-790-2672 Email: [email protected] http://www.hps.org In accordance with current knowledge of radiation health risks, the Health Physics Society recommends against quantitative estimation of health risks below an individual dose of 5 rem1 in one year or a lifetime dose of 10 rem above that received from natural sources. Doses from natural background radiation in the United States average about 0.3 rem per year. A dose of 5 rem will be accumulated in the first 17 years of life and about 25 rem in a lifetime of 80 years. Estimation of health risk associated with radiation doses that are of similar magnitude as those received from natural sources should be strictly qualitative and encompass a range of hypothetical health outcomes, including the possibility of no adverse health effects at such low levels. There is substantial and convincing scientific evidence for health risks following high-dose exposures. However, below 5–10 rem (which includes occupational and environmental exposures), risks of health effects are either too small to be observed or are nonexistent. In part because of the insurmountable intrinsic and methodological difficulties in determining if the health effects that are demonstrated at high radiation doses are also present at low doses, current radiation protection standards and practices are based on the premise that any radiation dose, no matter how small, may result in detrimental health effects, such as cancer and hereditary genetic damage. -
Distribution Coefficients of Polonium Between 0.75 M HDEHP in Cyclo- Hexane and Aqueous Hydrochloric and Nitric Acids Guogang Jia* and Giancarlo Torri
18 The Open Inorganic Chemistry Journal, 2008, 2, 18-21 Distribution Coefficients of Polonium Between 0.75 M HDEHP in Cyclo- hexane and Aqueous Hydrochloric and Nitric Acids Guogang Jia* and Giancarlo Torri Agency for Environmental Protection and for Technical Services, Via V. Brancati 48, 00144 Roma, Italy Abstract: The distribution coefficients (D) of polonium between 0.75 M di(2-ethyhexyl)phosphoric acid (HDEHP) in cy- clohexane and aqueous hydrochloric and nitric acids have been studied. Results indicate that: (1) D values are ranged from 32.7 to 0.00048 when the HCl acidities vary from 0.10 to 10.0 M, showing that polonium can well be extracted by 0.75 M HDEHP in cyclohexane if the aqueous HCl acidities are 0.050 M and it will not be extracted if 0.10 M HCl; (2) D values are ranged from 47.1 to 0.0117 when the HNO3 acidities vary from 0.10 to 10.0 M, showing that polonium can be extractable by 0.75 M HDEHP in cyclohexane and in a wide range acidity of 4 M HNO3. The different extraction behaviours of polonium in 0.75 M HDEHP in cyclohexane and different acidities of HCl and HNO3 were found. The find- ings will be very helpful to improve the methods involving polonium decontamination for determination and separation of americium, curium as well as other radioelements in environmental soil, water and biological samples. Keywords: Polonium, HDEHP, distribution coefficients. 1. INTRODUCTION on its oxidation state. Therefore, question is raised: which oxidation state is responsible for major polonium volatility, The element polonium (210Po) was discovered by Marie valences of +2, +4, and probably +6? Curie as the first element separated from pitchblende, and named after her home country, Poland [1, 2]. -
Po and Pb in the Terrestrial Environment
Current Advances in Environmental Science (CAES) 210Po and 210Pb in the Terrestrial Environment Bertil R.R. Persson Medical Radiation Physics, Lund University S-22185 LUND, Sweden [email protected] Abstract- The natural sources of 210Po and 210Pb in the meat at high northern latitudes. This was, however, of terrestrial environment are from atmospheric deposition, soil natural origin and no evidence of significant contributions and ground water. The uptake of radionuclides from soil to of 210Po from the atomic bomb test was found. The most plant given as the soil transfer factor, varies widely between significant radionuclides in the fallout from the atmospheric various types of crops with an average about ± atomic bomb-test of importance for human exposure were The atmospheric deposition of 210Pb and 210Po also affect the 137Cs and 90Sr [4]. activity concentrations in leafy plants with a deposition th 210 210 transfer factor for Pb is in the order of 0.1-1 (m2.Bq-1) plants During the 1960 century the presence of Pb and and for root fruits it is < 0.003, Corresponding values for 210Po 210Po was extensively studied in human tissues and are about a factor 3 higher. particularly in Arctic food chains [4-20]. The activity concentration ratios between milk and various types of forage for 210Pb were estimated to ± and for In December of 2006, former Russian intelligence 210Po to ±By a daily food intake of 16 kg dry matter operative Alexander Litvinenko died from ingestion of a 210 210 per day the transfer coefficient Fm. for Pb was estimated to few g of Po. -
Basics of Radiation Radiation Safety Orientation Open Source Booklet 1 (June 1, 2018)
Basics of Radiation Radiation Safety Orientation Open Source Booklet 1 (June 1, 2018) Before working with radioactive material, it is helpful to recall… Radiation is energy released from a source. • Light is a familiar example of energy traveling some distance from its source. We understand that a light bulb can remain in one place and the light can move toward us to be detected by our eyes. • The Electromagnetic Spectrum is the entire range of wavelengths or frequencies of electromagnetic radiation extending from gamma rays to the longest radio waves and includes visible light. Radioactive materials release energy with enough power to cause ionizations and are on the high end of the electromagnetic spectrum. • Although our bodies cannot sense ionizing radiation, it is helpful to think ionizing radiation behaves similarly to light. o Travels in straight lines with decreasing intensity farther away from the source o May be reflected off certain surfaces (but not all) o Absorbed when interacting with materials You will be using radioactive material that releases energy in the form of ionizing radiation. Knowing about the basics of radiation will help you understand how to work safely with radioactive material. What is “ionizing radiation”? • Ionizing radiation is energy with enough power to remove tightly bound electrons from the orbit of an atom, causing the atom to become charged or ionized. • The charged atoms can damage the internal structures of living cells. The material near the charged atom absorbs the energy causing chemical bonds to break. Are all radioactive materials the same? No, not all radioactive materials are the same. -
Experimental Γ Ray Spectroscopy and Investigations of Environmental Radioactivity
Experimental γ Ray Spectroscopy and Investigations of Environmental Radioactivity BY RANDOLPH S. PETERSON 216 α Po 84 10.64h. 212 Pb 1- 415 82 0- 239 β- 01- 0 60.6m 212 1+ 1630 Bi 2+ 1513 83 α β- 2+ 787 304ns 0+ 0 212 α Po 84 Experimental γ Ray Spectroscopy and Investigations of Environmental Radioactivity Randolph S. Peterson Physics Department The University of the South Sewanee, Tennessee Published by Spectrum Techniques All Rights Reserved Copyright 1996 TABLE OF CONTENTS Page Introduction ....................................................................................................................4 Basic Gamma Spectroscopy 1. Energy Calibration ................................................................................................... 7 2. Gamma Spectra from Common Commercial Sources ........................................ 10 3. Detector Energy Resolution .................................................................................. 12 Interaction of Radiation with Matter 4. Compton Scattering............................................................................................... 14 5. Pair Production and Annihilation ........................................................................ 17 6. Absorption of Gammas by Materials ..................................................................... 19 7. X Rays ..................................................................................................................... 21 Radioactive Decay 8. Multichannel Scaling and Half-life ..................................................................... -
NATO and NATO-Russia Nuclear Terms and Definitions
NATO/RUSSIA UNCLASSIFIED PART 1 PART 1 Nuclear Terms and Definitions in English APPENDIX 1 NATO and NATO-Russia Nuclear Terms and Definitions APPENDIX 2 Non-NATO Nuclear Terms and Definitions APPENDIX 3 Definitions of Nuclear Forces NATO/RUSSIA UNCLASSIFIED 1-1 2007 NATO/RUSSIA UNCLASSIFIED PART 1 NATO and NATO-Russia Nuclear Terms and Definitions APPENDIX 1 Source References: AAP-6 : NATO Glossary of Terms and Definitions AAP-21 : NATO Glossary of NBC Terms and Definitions CP&MT : NATO-Russia Glossary of Contemporary Political and Military Terms A active decontamination alpha particle A nuclear particle emitted by heavy radionuclides in the process of The employment of chemical, biological or mechanical processes decay. Alpha particles have a range of a few centimetres in air and to remove or neutralise chemical, biological or radioactive will not penetrate clothing or the unbroken skin but inhalation or materials. (AAP-21). ingestion will result in an enduring hazard to health (AAP-21). décontamination active активное обеззараживание particule alpha альфа-частицы active material antimissile system Material, such as plutonium and certain isotopes of uranium, The basic armament of missile defence systems, designed to which is capable of supporting a fission chain reaction (AAP-6). destroy ballistic and cruise missiles and their warheads. It includes See also fissile material. antimissile missiles, launchers, automated detection and matière fissile радиоактивное вещество identification, antimissile missile tracking and guidance, and main command posts with a range of computer and communications acute radiation dose equipment. They can be subdivided into short, medium and long- The total ionising radiation dose received at one time and over a range missile defence systems (CP&MT). -
Nuclide Safety Data Sheet Iron-59
59 Nuclide Safety Data Sheet 59 Iron-59 Fe www.nchps.org Fe I. PHYSICAL DATA 1 Gammas/X-rays: 192 keV (3% abundance); 1099 keV (56%), 1292 keV (44%) Radiation: 1 Betas: 131 keV (1%), 273 keV (46%), 466 keV (53%) 2 Gamma Constant: 0.703 mR/hr per mCi @ 1.0 meter [1.789E-4 mSv/hr per MBq @ 1.0 meter] 1 Half-Life [T½] : Physical T½: 44.5 day 3 Biological T½: ~1.7 days (ingestion) ; much longer for small fraction Effective T½: ~1.7 days (varies; also small fraction retained much longer) Specific Activity: 4.97E5 Ci/g [1.84E15 Bq/g] max.1 II. RADIOLOGICAL DATA Radiotoxicity4: 1.8E-9 Sv/Bq (67 mrem/uCi) of 59Fe ingested [CEDE] 4.0E-9 Sv/Bq (150 mrem/uCi) of 59Fe inhaled [CEDE] Critical Organ: Spleen1, [blood] Intake Routes: Ingestion, inhalation, puncture, wound, skin contamination (absorption); Radiological Hazard: Internal Exposure; Contamination III. SHIELDING Half Value Layer [HVL] Tenth Value Layer [TVL] Lead [Pb] 15 mm (0.59 inches) 45 mm (1.8 inches) Steel 35 mm (1.4 inches) 91 mm (3.6 inches) The accessible dose rate should be background but must be < 2 mR/hr IV. DOSIMETRY MONITORING - Always wear radiation dosimetry monitoring badges [body & ring] whenever handling 59Fe V. DETECTION & MEASUREMENT Portable Survey Meters: Geiger-Mueller [e.g. PGM] to assess shielding effectiveness & contamination Wipe Test: Liquid Scintillation Counter, Gamma Counter VI. SPECIAL PRECAUTIONS • Avoid skin contamination [absorption], ingestion, inhalation, & injection [all routes of intake] • Use shielding (lead) to minimize exposure while handling of 59Fe • Use tools (e.g. -
HEALTH PHYSICS SOCIETY POLICY on EXPENDITURE of FUNDS for IONIZING RADIATION HEALTH EFFECTS STUDIES Approved by the Board of Directors: November 1998
HEALTH PHYSICS SOCIETY Specialists in Radiation Safety HEALTH PHYSICS SOCIETY POLICY ON EXPENDITURE OF FUNDS FOR IONIZING RADIATION HEALTH EFFECTS STUDIES Approved by the Board of Directors: November 1998 PREMISE: 1. Funding resources for studying the health effects of human exposure to ionizing radiation are limited. 2. The number of research and study activities related to studying and understanding the health effects of ionizing radiation exceeds the funding resources available. 3. The highest priority of funding work on ionizing radiation health effects should be work with a reasonable likelihood of defining, or significantly increasing the understanding of, the carcinogenic response in the range of occupational and public exposures. 4. A second priority of funding work on ionizing radiation health effects should be work assisting in the establishment of reasonable protection criteria which do not result in an inappropriate expenditure of public funds for purported protection. This is necessary for the period in which there is a lack of definitive knowledge or understanding of the dose response. 5. Epidemiological studies alone will not provide definitive evidence of the existence or non-existence of carcinogenic effects due to low dose or low dose-rate radiation. RECOMMENDATIONS: 1. Do not fund epidemiological studies of exposed populations which have low statistical power and are unable to detect health effects with a reasonable statistical confidence (e.g., 90% or higher) based on the current risk estimates. 2. Do not fund epidemiological studies on populations for which there is insufficient data to properly control for known confounding factors, such as smoking history, exposure to other carcinogens, genetic pre-disposition, etc. -
Uranium Fact Sheet
Fact Sheet Adopted: December 2018 Health Physics Society Specialists in Radiation Safety 1 Uranium What is uranium? Uranium is a naturally occurring metallic element that has been present in the Earth’s crust since formation of the planet. Like many other minerals, uranium was deposited on land by volcanic action, dissolved by rainfall, and in some places, carried into underground formations. In some cases, geochemical conditions resulted in its concentration into “ore bodies.” Uranium is a common element in Earth’s crust (soil, rock) and in seawater and groundwater. Uranium has 92 protons in its nucleus. The isotope2 238U has 146 neutrons, for a total atomic weight of approximately 238, making it the highest atomic weight of any naturally occurring element. It is not the most dense of elements, but its density is almost twice that of lead. Uranium is radioactive and in nature has three primary isotopes with different numbers of neutrons. Natural uranium, 238U, constitutes over 99% of the total mass or weight, with 0.72% 235U, and a very small amount of 234U. An unstable nucleus that emits some form of radiation is defined as radioactive. The emitted radiation is called radioactivity, which in this case is ionizing radiation—meaning it can interact with other atoms to create charged atoms known as ions. Uranium emits alpha particles, which are ejected from the nucleus of the unstable uranium atom. When an atom emits radiation such as alpha or beta particles or photons such as x rays or gamma rays, the material is said to be undergoing radioactive decay (also called radioactive transformation). -
Radiation Basics
Environmental Impact Statement for Remediation of Area IV \'- f Susana Field Laboratory .A . &at is radiation? Ra - -.. - -. - - . known as ionizing radiatios bScause it can produce charged.. particles (ions)..- in matter. .-- . 'I" . .. .. .. .- . - .- . -- . .-- - .. What is radioactivity? Radioactivity is produced by the process of radioactive atmi trying to become stable. Radiation is emitted in the process. In the United State! Radioactive radioactivity is measured in units of curies. Smaller fractions of the curie are the millicurie (111,000 curie), the microcurie (111,000,000 curie), and the picocurie (1/1,000,000 microcurie). Particle What is radioactive material? Radioactive material is any material containing unstable atoms that emit radiation. What are the four basic types of ionizing radiation? Aluminum Leadl Paper foil Concrete Adphaparticles-Alpha particles consist of two protons and two neutrons. They can travel only a few centimeters in air and can be stopped easily by a sheet of paper or by the skin's surface. Betaparticles-Beta articles are smaller and lighter than alpha particles and have the mass of a single electron. A high-energy beta particle can travel a few meters in the air. Beta particles can pass through a sheet of paper, but may be stopped by a thin sheet of aluminum foil or glass. Gamma rays-Gamma rays (and x-rays), unlike alpha or beta particles, are waves of pure energy. Gamma radiation is very penetrating and can travel several hundred feet in air. Gamma radiation requires a thick wall of concrete, lead, or steel to stop it. Neutrons-A neutron is an atomic particle that has about one-quarter the weight of an alpha particle.