Radionuclide Concentrations in Water
Michael Pöschl, Leo M. L. Nollet in Radionuclide Concentrations in Food and the Environment, 2006
Besides the local effects due to accidents, there is a very interesting scenario in the Arctic Ocean, where the concentrations of plutonium are much higher than those predicted from fallout and releases from Sellafield (U.K.) and La Hague (France). Hence, two major hypotheses for this plutonium excess are being considered: (1) the local effect from nuclear tests in Novya Zemlia (former USSR), and (2) intake through the Ob and Techa Rivers (Siberia) from reprocessing plants and direct storing of high-radioactivity wastes. It is possible to identify the plutonium origin depending on the 238Pu/239,240Pu isotope ratio. Hence the activity ratio is approximately 0.18 for plutonium originating from fallout and deviates from this ratio for releases from reprocessing plants [67].
Miscellaneous Applications
Vlado Valković in Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
Several techniques have been used for the measurement of trace amounts of plutonium. Among them, the most commonly used method is alpha-spectrometry. With alpha-spectrometry, the isotope ratio of 239Pu/240Pu cannot be measured because the alpha-particles from both isotopes have nearly identical energies. The 239Pu/240Pu ratio often carries the most important information in a case study, as it reveals the original source (nuclear bombs or reactors of certain types) of plutonium. Among all the analytical methods available today, mass spectrometry seems to be the most promising one to fulfill this need. Both thermal ionization and inductively coupled plasma mass spectrometry (ICP-MS) have reasonable ionization efficiency for plutonium, but they cannot eliminate the hydride and other molecular interferences to yield reliable results. AMS, on the other hand, is capable of counting and identifying an individual atom without any molecular interference. However, the ionization and transmission efficiencies of plutonium in a Tandetron-based AMS system are expected to be low. But the unique feature of AMS, which is necessary for trace-amount plutonium detection, warrants an effect to determine these efficiencies experimentally so that the usefulness of AMS for measuring the plutonium ratio in environmental samples can be established (Litherland 1995).
Radiation Hormesis in Cancer
T. D. Luckey in Radiation Hormesis, 2020
Plutonium occurs as insoluble complexes in soil and dust; there is very little in food.252 Attachment of plutonium to skin and hair poses no hazard since the alpha rays cannot penetrate the dermis. Most salts of plutonium are insoluble and poorly absorbed due to the formation of very insoluble polymeric hydroxides. Of the plutonium absorbed, about 30% goes to the blood and 50% to bones. An adult contains about 74 mBq of plutonium.124,649 The concentration of plutonium in lymph nodes is about ten times greater than that of bone; however, the cumulative weight of lymph nodes is only 15 g in a 70 kg adult. Bone and liver contain the most, 100 mBq and 48 mBq, respectively. Although lungs contain less, about 7 mBq; much is concentrated at the bifurcation points of the bronchii, the “hot spots” of the lung.604
Radiological risk assessment of the Hunters Point Naval Shipyard (HPNS)
Published in Critical Reviews in Toxicology, 2022
Dennis J. Paustenbach, Robert D. Gibbons
Pu-239 has a radioactive half-life of 24,110 years and is produced when uranium absorbs a neutron. Small amounts of plutonium occur naturally, but large quantities have been produced in nuclear reactions or released from atmospheric nuclear weapons tests. Pu-239 transitions by alpha decay. Its decay products emit alpha, beta, and gamma radiation depending upon which radionuclide is being evaluated and can pose both an internal and external radiation hazard. Pu-239 is present in most soils in the United States at various concentrations (ICRP 2008; Johnson et al. 2012). The potential for Pu-239 to be present on ships returning from nuclear weapons tests in the Pacific and Pu-239 use in calibrating radiation detection equipment were primary reasons it was identified as an ROC at HPNS (USN 2004).
Mortality among workers at the Los Alamos National Laboratory, 1943–2017
Published in International Journal of Radiation Biology, 2022
John D. Boice, Sarah S. Cohen, Michael T. Mumma, Ashley P. Golden, Sara C. Howard, David J. Girardi, Elizabeth Dupree Ellis, Michael B. Bellamy, Lawrence T. Dauer, Caleigh Samuels, Keith F. Eckerman, Richard W. Leggett
Table 8 shows the relative risk (hazards ratio) for lung cancer over categories of external dose and internal plutonium dose for 26,324 workers first employed at LANL between 1943–1980 and followed through 2017. External dose to the lung was taken as the contributions of dose from photons, neutrons, and tritium. The referent group was taken as the 21,745 workers with cumulative lung doses <5 mGy for both external lung dose and internal plutonium alpha-particle lung dose. Modeling the joint effects of external and internal exposures is imprecise since only 19 lung cancers occurred among the 447 workers with >5 weighted-mGy lung doses from plutonium intakes. Nonetheless, adjusting for sex, education, year of birth, and external dose to the lung, the HR at 100 weighted-mGy plutonium dose were 1.15 (95%CI 0.66,1.99; n = 839). The trend was not statistically significant (p = .62).
A review of the impact on the ecosystem after ionizing irradiation: wildlife population
Published in International Journal of Radiation Biology, 2022
Georgetta Cannon, Juliann G. Kiang
Twenty-one years later after the Chernobyl power plant explosion, various isotopes of plutonium, strontium-90, americium-241, and cesium-137 were still detected at high levels causing adverse biological effects across the nearby areas (Voitsekhovych et al. 2007). Wildlife continued to be exposed to substantial radiation doses after humans were evacuated from these areas. The half-life of cesium-137 is approximately 30 years and it decays by β emission to a metastable isomer of barium-137. The half-life of barium-137 isomer is 2 minutes. Subsequently, the metastable isomer emits γ radiation and becomes ground state barium (Baum et al. 2002). Food or water contaminated with cesium-137 that are ingested lead to internal β and γ radiation doses in addition to external radiation doses. The half-life of cesium-134 is about 2 years. Cesium-134 emits β particles. The half-life of strontium-90 is approximately 29 years. Strontium-90 emits pure β radiation. Most of the plutonium isotopes emit α particles, which are ionizing and harmful, but have a short penetration distance. The half-life of plutonium-241 is approximately 14 years. It emits β radiation to become americium-241. The half-life of americium-241 is 432 years, and it emits α particles to become neptunium-237, with a by-product of γ emissions (Baum et al. 2002). This is the composition of radiation released and retained in the soil, water and air across the Chernobyl landscape. In addition to external radiation exposure, ingestion of contaminated food and water by wildlife occurred from the beginning of the disaster and continues to the present.
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