No abstract available

No abstract available

No abstract available

[en] In 1979, a radiation worker who, 25 years earlier, had acquired an internal deposit of ²⁴¹Am died, willing his body for analysis to the US Transuranium Registry (TUR). In a cooperative effort with the Registry and several other laboratories, all tissues and half of the skeleton were anlayzed radiochemically, with the results to be published in detail. We report here our contribution to this cooperative analysis - the development of a new general metabolic model for the actinides (with appropriate parameters for Am), a model that takes account of circulatory feedback and includes two bone components with different remodeling rates

[en] The kinetics of deposition of intravenously (i.v.) injected ²³⁸Pu(IV) citrate were determined in the mouse to provide baseline information needed to assess the effectiveness of plutonium removal agents and to identify their mechanisms of action. Data reported here for ten post-injection intervals from 1 min to 24 hr after an i.v. injection were used to prepare a preliminary mathematical description of the simultaneous deposition of ²³⁸Pu in liver and skeleton and its clearance from plasma and extracellular fluid (ECF), as inferred from the ²³⁸Pu content of soft tissues other than liver. For completeness, retention of ²³⁸Pu in the major tissue compartments from 24 hr to 14 days after injection is included

[en] Radionuclide-contaminated wounds are of radiological concern because the wound provides a portal of entry of the radionuclide to the systemic circulation, and can also be a tissue at risk if sufficient dose is deposited at the wound site. Accordingly, a scientific committee established jointly by the US National Council on Radiation Protection and the International Commission on Radiological Protection has been developing an approach to describing the biokinetics of radionuclides deposited in wounds and calculating dose to the wound site. This paper focuses on the analyses, performed principally using experimental animal data, that have led to the development of a biokinetic model for deposited soluble radionuclides as well as more insoluble forms, such as colloids, particles and fragments. The available data for injected soluble materials have provided a basis for categorising 48 different elements (from Be to Cm and representing all of the chemical groups, except halogens and noble gases) into four distinct retention groups. In general, the data are adequate for developing a mechanistically based biokinetic model, whose application is exemplified for soluble radionuclides. (author)

[en] To determine the relationship between urinary excretion and plutonium body content, 18 persons of short life expectancy were injected with plutonium between 1945 and 1947. Seventeen of these 18 individuals have been identified; eight were found to have survived for at least eight years and four are still alive today (1975). The causes of death of 13 of these individuals have been determined from death certificates; none appear to be related to the administered plutonium. Doses to the liver and to the cells on the surface of bone have been calculated for these plutonium cases. The liver doses do not appear to be high enough to be carcinogenic, but comparison of the bone-surface doses with radium doses that have induced bone tumors indicates that six of these cases have received doses high enough to be considered carcinogenic. However, no bone tumors have yet appeared. (auth)

[en] This pilot study of the initial distribution of ²³⁷Np(V,IV) in an adult Macaque monkey was undertaken to begin upgrading the biological data for Np using an animal phylogenetically close to man, to demonstrate that it was possible to measure small amounts of ²³⁷Np in biological samples accurately by means of its photon emission, and to provide detailed initial distribution data on soft tissues and within the skeleton for an actinide element with a stable (V) state, for comparison with similar data we have obtained for ⁹⁰Sr(II), ²⁴¹Am(III), ²³⁸Pu(IV), and ²³³U(IV) in adult Macaques. 22 refs., 1 fig., 5 tabs

[en] This paper summarizes the results of animal experiments that are the foundation of our current understanding of the biological behavior or uranium. Topics discussed include: metabolism including biological transport, excretion, deposition and retention in kidney and bone; absorption after parenteral administration, feeding, inhalation, or application to skin or eye; maternal transfer; and clearance of inhaled compounds from the lung. Acute chemical toxicity, including mechanism of action and effects on renal tubules; effects on blood and urine chemistry; acute mortality after parenteral administration or application to skin or eye; and the acute toxicity of ²³³U. Chemical toxicity after prolonged exposure, including mortality; kidney function and pathology during chronic ingestion or inhalation; and tolerance to uranium poisoning. Radiation effects, including induction of bone tumors by soluble ²³²U or ²³³U; subacute mortality from ²³³U; pneumonia and fibrosis in lung and induction of lung tumors by inhaled oxides of ²³⁵U or natural U

[en] The following topics are discussed: actinide elements in energy systems; biological hazards of the actinides; radiation protection standards; and purposes of actinide biological research with regard to toxicity, metabolism, and therapeutic regimens