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Toxic Responses of the Liver
Published in Stephen K. Hall, Joana Chakraborty, Randall J. Ruch, Chemical Exposure and Toxic Responses, 2020
Many occupational chemicals (e.g., dyes, metals, solvents), pesticides (e,.g., DDT, aldrin, lindane), dietary factors and contaminants (e.g., alcohol, anatoxin, nitrosamines), and pharmaceutical agents (e.g., phenobarbital, diazepam, clofibrate) induce liver cancer. Many of these agents do so only in experimental animals and are probably not a risk factor for human liver cancer. Agents such as anatoxins and alcohol, however, are clearly liver carcinogens in man. The types of cancers that arise in the liver are specific to the carcinogenic agent. Most hepatic cancers develop from hepatocytes and are known as hepatocellular carcinomas. However, some carcinogens cause the formation of liver tumors from other cells. Vinyl chloride and arsenic, for example, induce tumors from endothelial cells (hemangiosarcomas). Thorium dioxide, also known as Thorotrast, was used from 1920 to 1950 as a radioactive contrast agent; this agent induces tumors from endothelial cells, hepatocytes, and biliary cells (cholangiocarcinomas).
Hydrogen-moderated systems
Published in Kenneth Jay, Nuclear Power, 2019
The first distinctive feature is that the plant burns thorium; it is in fact the first to do so. The fuel is a mixture of thoria (thorium dioxide) and uranium dioxide, the uranium in the latter being practically pure uranium-235; the proportions of the two oxides are such that about 5 per cent of the atoms in the mixture are uranium-235. Thus, as far as enrichment goes, the fuel is not unlike the uranium dioxide at the Yankee Atomic station with its 3 per cent of uranium-235, but there is the fundamental difference that since the fertile component of the mixture is thorium instead of uranium-238, the new fuel formed will be uranium-233 instead of plutonium. Some of this uranium-233 will be burned, just as some of the plutonium is burned at Shippingport (or Hinkley Point for that matter), and some will be left behind in the used fuel and could be extracted. The plant will thus provide operational experience with a new nuclear fuel about which much has been written but little is known practically. The reactor is not, however, a breeder; its conversion factor is in fact quite low, about 0.5.
Radiological toxicity of some fish and meat tissues consumed in southwestern Nigeria
Published in Human and Ecological Risk Assessment: An International Journal, 2018
Oladele Samuel Ajayi, Emmanuel Oluwanifesii Fatile, Chidiebere Goodluck Dike
The ingestion and inhalation of naturally occurring radionuclides from the environment give rise to a dose which varies according to the location, diet, and habit of the organism concerned. Some of the radionuclides that can be found in the human body are 40K, and nuclides from uranium and thorium series. Several animal studies (Wesch et al.1983; Riedel et al.1983; Taylor et al.1986) showed the carcinogenic potency of 232Th on the liver. These researchers injected thorium dioxide, ThO2, compound into animals. The injected animals developed liver cancers after a period of time. Thorium can also accumulate in the lungs if its route into the body is by inhalation. Insoluble compounds are more toxic to the lungs because they are not easily absorbed into the blood stream.
A Preliminary Economic Assessment of Thorium-Based Fuels in a Pressure Tube Heavy Water Reactor
Published in Nuclear Technology, 2018
Alberto D. Mendoza España, Megan Moore, Ashlea V. Colton, Blair P. Bromley
The fuel concepts studied consist of modifications to fuel composition, central element materials, and the addition of thorium dioxide.7 Three types of fuel bundle concepts were assessed in calculating fuel cycle costs: BUNDLE-37 (B37), BUNDLE-37-mod (B37mod), and BUNDLE-35 (B35), which are described in more detail elsewhere.7–10 Each fuel bundle is associated with different lattice concepts, which are described in Table I and shown in Figs. 3, 4, and 5.
Conceptual Neutronics Study of a Hybrid Fusion Neutron Source FNS-C with Aqueous Blanket
Published in Fusion Science and Technology, 2023
A. V. Zhirkin, V. P. Budaev, A. V. Dedov, A. A. Glebova, A. O. Goltsev, A. T. Komov, B. V. Kuteev
The aqueous blanket occupies the entire volume of the computational model outside the solid-state blanket and the coils of the PMFC. It consists of a mixture of a fast neutron moderator: D2O and thorium dioxide 232ThO2. The aqueous blanket can be enriched with the fissile nuclide 233U. The atomic weight of the thorium dioxide is 264.037 g/mol, and its density is 10 g/cm3. The mixture is prepared in the proportion of 34.95 g of thorium dioxide per 100 g of D2O.