Determination of the plutonium-239 content of the body

In order to increase the informativeness of the indirect dosimetric estimates of plutonium-239 body levels complex makers are widely used to enhance natural excretion of the radionuclide in urine, the ratio between 239Pu levels in urine and skeleton being measured. However, as the onset of chelate application is postponed its efficacy, with respect to the skeleton, sharply decreases making it impossible to obtain reliable information concerning plutonium 239 levels in bone tissues at later times.     

Possibility of a change in the parameters of plutonium-238 metabolism in the body

The influence of macro amounts of iron on 238Pu metabolism in the animal body has been studied. The data obtained indicate that 238Pu metabolism parameters change under the effect of iron. The efficiency of the agent used is demonstrated by a diminished deposition of the radionuclide in bone tissues and an increased (by 2.65 times as compared with the control) excretion of plutonium 238 in faeces.     

Distribution of plutonium-239 in the body of dogs 7 days after the intravenous administration of a citrate complex of the metal

In experiments with 12 dogs of both sexes it was found that 7 days after intravenous injection of the citrate (2%) complex the concentration of plutonium in the organs and tissues, which are considered noncritical, is lower than in the skeleton by one or two orders of magnitude. No substantial differences were found in plutonium levels in the endocrine glands, (0.7-4.2) X 10(-3%), different parts of the gastrointestinal tract, (0.9-1.7) X 10(-3%), different regional lymph nodes, (2.4-3.8) X 10(-3%), and in different parts of the central nervous system, (0.06-0.19) X 10(-3%) of the total amount of plutonium administered.     

The distribution of intratracheally administered plutonium-239 throughout the skeletal bones]

The data are presented on distribution of the intratracheally administered plutonium-239 within the skeleton bones. Plutonium was found to be distributed non-uniformly within the skeleton: it was concentrated mainly in the bones where the trabecular fraction of the bone tissue was most manifest. The results obtained were supported by the correlation analysis.     

Effect of plutonium-239 on the mitotic activity of mouse bone marrow cells

Summary Mitotic index of the bone marrow cells was studied in femoral bone marrow of mice given 313 kBq²³⁹Pu kg^–1. The attention was turned to the femoral midshaft and the mitose concentration, intensified by Colcemid stathmokinetic effect, was evaluated in a sampling field from endosteal surface to the central venous canal, throughout 68 weeks. It has been found that the plutonium effect in the sampling band is rather uniform except the points in subendosteal zone early after plutonium injection, where the mitotic index was reduced in such a way that the mitotic gradient, observed in controls, was affected. The mitotic activity in femoral diaphysis of plutonium injected mice was mobilized approximately till the 30th week of contamination. Later it deteriorated progressively. The results are discussed and should not be regarded as representative for the entire bone marrow hemopoiesis.     

Alkaline phosphatase and transaminase activity in the liver and blood serum of rats in the late periods following combined exposure to external gamma radiation and alpha radiation from plutonium-239

A study was made of activity of alkaline phosphatase and alanine- and aspartate aminotransferase in rat liver and blood serum at remote times after external gamma-irradiation combined with internal exposure to 239Pu nitrate delivered in two chronically effective doses. The radionuclide was shown to be mainly responsible for the changes observed in activity of the enzymes under study. The degree to which the changes were manifest depended upon dose of plutonium administered.     

The effect of iron on the excretion by rats of intratracheally administered plutonium-239

A study was made of the effect of ferric citrate on excretion of intratracheally administered plutonium-239. The preparation used permitted to increase the radionuclide excretion via the gastrointestinal tract by 1.8 times as compared to the control. The positive effect of the iron preparation was maximally displayed between days 4 and 11 following administration: the value of the increase was 2.2.     

Longevity of animals in combined exposure to total gamma irradiation and incorporated plutonium-239

The paper presents the functions and nomograms permitting to estimate the expected consequences of the combined effect of alpha-radiation from incorporated plutonium 239 and external gamma-rays at random doses on the lifetime of animals.     

The ultrastructure of mouse testicular interstitial tissue containing plutonium-239 and its significance in explaining the observed distribution of plutonium in the testis.

The technique of autoradiography with Araldite-embedded sections was used to study the distribution of 239Pu in mouse testis at various times post-injection. Adjacent sections were examined with both the light microscope and electron microscope. The autoradiographs showed that from 1 week to 3 months postinjection, most 239Pu in located in interstitial tissue. The major change in distribution observed was that the early diffuse deposit in interstitial tissue is concentrated in macrophages with increasing time post-injection. This is a real change of distribution as the amount of 239Pu in mouse testis remains constant from 1 week to 3 months post-injection. Study of the ultrastructure of interstitial tissue indicated that the accumulation of 239Pu in macrophages may be brought about in two ways. First, there may be phagocytosis of dead cells containing 239Pu. Second, 239Pu may follow the transfer of waste products of hormone synthesis from Leydig cells into macrophages. The significance of these observations is discussed with regard to the deposition of 239Pu in human testis.     

Cytogenetic mechanisms of aneuploidy in somatic cells of chemonuclear industry professionals with incorporated plutonium-239

Risks related to occupational exposure of humans to ionizing radiation remains a focus of attention. Of special importance is the poorly understood effect of ionizing radiation on the rate of numerical chromosome aberrations in human somatic cells. The purpose of this study was characterization of a radiation-induced increase in the rate of aneuploidy induced by incorporated plutonium-239 (²³⁹Pu) in somatic cells of chemonuclear industry workers. Significant differences in the chromosome 2, 7, 8, 12, and Y aneuploidy rate have been found between subjects with incorporated ²³⁹Pu and control subjects have been demonstrated. Chromosome nondisjunction has been found to be the main mechanism of aneuploidy induced by incorporated ²³⁹Pu.