Special Problems of Internal Radioactive Materials
George W. Casarett in Radiation Histopathology, 2019
Plutonium-238 is an alpha emitter with a physical half-life of 50 years, and plutonium-239 is an alpha emitter with a physical half-life of 24,000 years. Plutonium-239 is a bone seeker which, inside the body, is about as hazardous as radium. However only 0.0026% is absorbed through the gastrointestinal tract as compared with 30% for radium. Absorption of plutonium from lung is also minimal. Plutonium disappears rapidly from the blood and the plutonium content of the skeleton rises rapidly to maximal levels in about 48 hr. About 80 to 90% of the body burden is eventually found in the skeleton, on bone surfaces, and in the organic matrix rather than in the mineral phase. Therefore relatively large amounts of plutonium are found in cancellous bone as compared with compact bone. There is a later redistribution to compact bone. The soft tissue with the greatest concentration is liver. Excretion is chiefly from the gastrointestinal tract and is slow. Nearly 90% of the element is retained for many years, chiefly in bone.
Radionuclides in water *
Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse in Routledge Handbook of Water and Health, 2015
There are numerous sources of anthropogenic (i.e., man-made) sources of radionuclides that have increased waterborne radionuclide concentrations locally, regionally, and worldwide. These sources include nuclear power plants, nuclear weapons production and reprocessing (e.g., Hanford, Washington, U.S.; Savannah River, South Carolina, U.S.; Mayak Production Association, Russia), permitted medical and industrial releases, nuclear weapons testing (e.g., Pacific Ocean and Nevada Test Site, U.S.; Semipalatinsk test site, Republic of Kazakhstan; Mururoa and Fangataufa atolls, French Polynesia), commercial fuel reprocessing (e.g., La Hague plant, France; Thermal Oxide Reprocessing Plant, Sellafield, England; Mayak Production Association, Russia), geological radioactive waste repositories, and nuclear accidents (e.g., Mayak, Russia; Chernobyl, Ukraine; Fukushima, Japan). Some of the man-made radionuclides of public health concern include cesium-137, iodine-131, iodine-129, plutonium-239, strontium-90, and uranium-235. For example, above ground nuclear testing increased anthropogenic radionuclides with longer half-lives in water worldwide including tritium (i.e., Hydrogen-3), plutonium-239 and 240, cesium-137, and strontium-90. Additional details about the various radionuclides are provided elsewhere (U.S. EPA, 2014; Weinhold, 2012; WHO, 2006).
Chain Reactions
Alan Perkins in Life and Death Rays, 2021
Uranium-235 production at Oak Ridge was undertaken by two methods, electromagnetic particle deflection and gaseous diffusion, but numerous setbacks and problems meant that only small amounts were produced. The Army and Navy also set up a third production process based on liquid thermal diffusion. Even with the three production streams, there was only enough uranium-235 for the construction of one bomb. Plutonium-239 was considered to be the most suitable material for use in the atomic bomb because it had a smaller critical mass than uranium and it could be produced in larger amounts in a nuclear reactor. Hanford near the Columbia River in Washington State was chosen as a further site for a reactor and processing facility to produce plutonium-239. This facility was managed by the DuPont Company, one of the largest US corporations at that time (Figure 6.4).
Facts and ideas from anywhere
Published in Baylor University Medical Center Proceedings, 2020
The long-term consequences of the Chernobyl disaster remain unclear. While the actual impact of the radiation exposure on the health of the population is still debated, there can be little doubt that the whole society was left traumatized for decades. Every sixth Ukrainian adult reports being in poor health, a significantly higher percentage than in neighboring countries. And those affected by the Chernobyl radiation have lower levels of employment and fewer working hours than the rest of Ukraine’s population. Despite the new shelter over the damaged reactor unit 4, the area around the nuclear plant will not be safe for human habitation for at least another 20,000 years. The half-life of cosium-137, one of the most harmful nuclides, is approximately 30 years. The iodine-135 half-life is only 8 days; cesium-134, 2 years; cesium-137, at least 180 years; and plutonium-239—traces of which were found as far away as Sweden—24,000 years.
The Russian Radiobiological Human Tissue Repository: characteristics of biological specimens donated by nuclear workers with lung cancer
Published in International Journal of Radiation Biology, 2020
Galina Zhuntova, Christopher Loffredo, Evgeniya Grigoryeva, Gleb Sychugov, Evgeny Kazachkov, Evgeniya Kirillova, Tamara Azizova
Mayak PA is located in the Southern Urals, close to Ozyorsk city of the Chelyabinsk region. It started its operation in 1948 and included reactors, radiochemical and plutonium production plants as well as auxiliary facilities. Reactor workers were externally exposed to gamma radiation over prolonged periods while workers of radiochemical and plutonium production plants were in addition exposed to alpha particles from plutonium-239. Auxiliary facility workers could also be exposed to gamma and alpha radiation.
Morphological features of pulmonary fibrosis in workers occupationally exposed to alpha radiation
Published in International Journal of Radiation Biology, 2020
Gleb Sychugov, Tamara Azizova, Sergey Osovets, Evgeny Kazachkov, Valentina Revina, Evgeniya Grigoryeva
PuPF registry which includes 188 cases was described in details by Azizova et al. (2020). PuPF frequency in the Mayak PA worker cohort was shown to increase significantly with a cumulative lung absorbed dose from alpha-emitting particles from incorporated plutonium-239 and to be independent on dose from external exposure to gamma rays. In papers reporting on radiation-induced health effects in the Mayak PA worker cohort (Azizova et al. 2008, 2015, 2017, 2018; Azizova, Bannikova, et al. 2019; Azizova, Briks, et al. 2019) the authors note that main advantages of the Mayak PA worker cohort are a long follow-up period, individually measured doses from external and internal radiation exposure over entire employment periods, complete medical information over entire follow-up period and available biological specimens of various organs and tissues collected from 30% of the cohort members (including 35.2% of workers with PuPF), which are stored at the Radiobiological Human Tissue Repository (RHTR) of the Southern Urals Biophysics Institute at the Federal Medical Biological Agency of Russia (Loffredo et al. 2017). Many papers reporting on Mayak PA worker cohort studies have been published in recent decades. These papers provided evidence to associations of cancer and non-cancer effects with both external exposure to gamma rays and internal exposure to alpha particles from plutonium (Sokolnikov et al. 2008; Gilbert et al. 2013; Azizova et al. 2015, 2017, 2018; Azizova, Briks, et al. 2019). Significant linear associations were found not only for lung cancer but also for chronic obstructive pulmonary disease (COPD) with cumulative lung absorbed doses from alpha-particles (Koshurnikova et al. 1972; Tokarskaya et al. 1995; Gilbert et al. 2013; Azizova et al. 2017). The Mayak Worker Dosimetry System is consistently improved within the framework of the US-Russian collaboration (Fountos 2017; Napier 2017). However, mechanisms of radiation-induced effects remain unclear.
Related Knowledge Centers
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- Half-Life
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