Radionuclide Sources
Michael Pöschl, Leo M. L. Nollet in Radionuclide Concentrations in Food and the Environment, 2006
Nuclear fission is the process by which neutrons produce chain reactions in a nuclear reactor. When a fissionable nucleus is hit by a thermal or slow neutron, the nucleus can interact with the neutron and divide (fission) into two smaller nuclei, releasing neutrons and energy that initiate the splitting of more fissionable atoms, leading to a chain reaction. 235U is the most abundant naturally available isotope that can undergo fission. Gaseous diffusion and other methods are used to enrich and separate the small amount of 235U (0.72% natural abundance) from the predominantly 238U found in nature. For most nuclear reactors, such as the light-water reactors, the enrichment required for a sustained nuclear reaction is approximately 10-fold. The more significant enrichment of 235U required for atomic weapons is a difficult and expensive task.
CBRN and the Trauma Victim
Ian Greaves, Keith Porter, Jeff Garner in Trauma Care Manual, 2021
A nuclear incident involves the process of splitting the atom (fission) usually either as a controlled process (power production) or nuclear weapon/detonation (chain reaction). Nuclear fission generates a vast amount of energy, mainly in the form of heat and ionizing radiation with the by-product of multiple fission products (usually beta-emitting, for example, strontium, caesium and iodine radioisotopes) and neutron-induced radioisotopes. In the case of nuclear detonation, addition features include a fireball, electromagnetic pulse (EMP) and blast wave. The result of a nuclear incident including an explosion is the potential for contaminated, blast, thermal and irradiated casualties, and a combination of these. Any concurrent significant irradiation and trauma have a synergistic effect with higher-than-expected death rates. Psychological effects should also not be underestimated.
The UN’s dalliance with nuclear power
Théodore H MacDonald, David Player, Mathura P Shrestha in Sacrificing the WHO to the Highest Bidder, 2018
Between 1945 and 1986, both the military and the scientific establishment learned a great deal about man-made radiation and its potential for genetic destruction. Also, however, the potential for the peaceful application of nuclear fission as an energy source became clearer. Not every country can produce uranium of sufficient quality for the manufacture of nuclear weapons, with the result that countries that could do so quickly found themselves in a most favourable economic position. For instance, Australia happens to hold about 40% of easily accessible uranium, and it is significant that, while selling the material widely to many other countries, Australia itself has been one of the most conservative countries in terms of adopting nuclear power as an energy source for domestic use, as we shall see later.
Modeling principles of protective thyroid blocking
Published in International Journal of Radiation Biology, 2022
Alexis Rump, Stefan Eder, Cornelius Hermann, Andreas Lamkowski, Manabu Kinoshita, Tetsuo Yamamoto, Junya Take, Michael Abend, Nariyoshi Shinomiya, Matthias Port
Nuclear fission processes release a large number of different fission products, including radioactive iodine nuclides. Uranium-235 usually splits asymmetrically and radioioiodine(s) fall(s) in one of the favored mass number regions of the fission products (peaks between 90–100 and 130–140). The main radioactive iodine isotopes formed by fission are iodine-131 (physical half-life, T1/2 = 8.02 d), iodine-129 (T1/2 = 1.57 107 y) and iodine-132 (T1/2 = 2.3 h; from Te-132) (ICRP 2017). Among the different iodine isotopes, iodine-131 is of particular importance (Blum and Eisenbud 1967). Iodine is characterized by its high volatility compared to most other fission products. In the case of nuclear incidents, e.g. nuclear power plant accidents or the detonation of a nuclear weapon, it must be expected that radioiodine will be released and also carried over greater distances (Verger et al. 2001; Chabot 2016). Radioiodine is quickly absorbed into the organism both by inhalation and via ingestion (Geoffroy et al. 2000; Verger et al. 2001). From a practical point of view, intake through contaminated drinking water and food probably plays the decisive role (Blum and Eisenbud 1967).
Why is the multiple stressor concept of relevance to radioecology?
Published in International Journal of Radiation Biology, 2019
B. Salbu, H. C. Teien, O. C. Lind, K. E. Tollefsen
Sources associated with nuclear fission such as the backend of the nuclear weapons and fuel cycles, include the simultaneous releases of a large number of different radionuclides representing spent fuel such as uranium as well as fission products, activation products and actinides. In case of a high temperature and high pressure event (e.g., nuclear detonation, reactor explosion, reactor fire), the release will also include a series of stable metals such as Zr and Nb due to interactions with cladding. Sources associated with the front end of the fuel cycles such as U mining, represent a legacy of long-lived naturally occurring radionuclides in close association with elements such as As and metals such as Cd, Ni, and Pb. Monitoring of the U.S. Superfund Waste Sites showed that radionuclides were commonly found not only together with metals, but also with contaminants such as volatile organic compounds, PAHs, and pesticides (Hinton and Aizawa 2007). Thus, one source can contribute to the release of multiple radionuclides as well as metals and organics to the environment, and assessing a limited number of stressors, one stressor at a time, may easily underestimate the risk.
Funding for radiation research: past, present and future
Published in International Journal of Radiation Biology, 2019
Kunwoo Cho, Tatsuhiko Imaoka, Dmitry Klokov, Tatjana Paunesku, Sisko Salomaa, Mandy Birschwilks, Simon Bouffler, Antone L. Brooks, Tom K. Hei, Toshiyasu Iwasaki, Tetsuya Ono, Kazuo Sakai, Andrzej Wojcik, Gayle E. Woloschak, Yutaka Yamada, Nobuyuki Hamada
In the EU, the EC proposed ‘Horizon Europe’ succeeding ‘Horizon 2020’. The proposed budget under Horizon Europe for the Euratom R&T Program is EUR 2.4 billion. The Euratom R&T Program is the only EU program that supports R&T and complements national funding. It supports R&T in both fission and fusion. Research in the context of non-power applications of ionizing radiation focuses on reduction of risks from low dose exposure through the use of these technologies. Research into radiation protection has already benefited the medical sector and has also a significant potential for public benefit in other sectors. The rapidly growing use of nuclear fission technologies worldwide makes Euratom research all the more important. The Euratom R&T also makes improvements in the areas of education, training and access to research infrastructure.
Related Knowledge Centers
- Argon
- Atom
- Gamma Ray
- Nuclear Reaction
- Radioactive Decay
- Atomic Nucleus
- Discovery of Nuclear Fission
- Fission
- Nuclear Transmutation
- Ternary Fission