The callus culture of Nicotiana tabacum L. was obtained from the plants chronically irradiated in 10 km zone of Chernobyl Atomic Power Station. The tobacco plants in 10 km zone of Chernobyl during the vegetation period exposed to irradiation with the average dose rate of 0.36 mA/kg (5 mP/h). The total absorbed dose was approximately 0,31 Gy. The morphogenetic analysis of this culture shows a considerable decrease of regeneration index and callus weight.
After the nuclear accident of Chernobyl, in the population of zones contaminated the malignant renal tumors was increased from 4.7 to 7.5 per 100,000 of total population. Cesium 137 (137Cs) constitutes 80-90% of the internal exposure of these people as well as eliminated through kidneys becomes an important risk factor. We present a case of a patient, residing in radiocontamined area, who consulted for abdominal pain and left flank mass. We review relevant literature and the management of these patients.
Cytogenetic analysis of chromosomal aberrations (CA) in 175,229 cells from 1113 individuals, both unexposed and occupationally or environmentally exposed to heavy metals (mercury and lead), organic (styrene, formaldehyde, phenol and benzo(a)pyrene) and inorganic (sulfur and nitrogen oxides, hydrogen and ammonium fluorides) volatile substances and/or ionizing radiation was performed. In addition, 11,250 cells from 225 individuals were scored for the frequency of sister-chromatid exchanges (SCE). Increased frequencies of CA were found in all occupationally exposed groups. A principal difference between the exposure to heavy metals and organic substances was found: increase in the CA frequency was dependent on duration of exposure to mercury but not dependent on duration of exposure to styrene, formaldehyde and phenol. A higher CA incidence was found in lymphocytes of children living in the vicinity of a plant manufacturing phosphate fertilizers. This indicates that children are a sensitive study group for the assessment of environmental exposure. However, the results of SCE analysis in these children were inconclusive. Exposure to ionizing radiation was found to cause chromosome breaks and chromatid exchanges in Chernobyl clean-up workers and chromatid breaks, chromatid exchanges, dicentric chromosomes and chromosome translocations in workers from the Ignalina Nuclear Power Plant. The increased frequency of chromatid exchanges in individuals exposed to ionizing radiation was quite unexpected. This may be attributed to the action of some unrecognized life-style or occupational factors, or to be a result of radiation-induced genomic instability. Also an increased SCE frequency was found in lymphocytes of Chernobyl clean-up workers.
This article describes the nutritional measures introduced to protect health after the Chernobyl accident, and the associated costs. The total value of the reindeer meat, mutton, lamb and goat meat saved as a result of such measures in 1987 amounted to approx. NOK 250 million. The measures cost approx. NOK 60 million. The resulting reduction in the radiation dose level to which the population was exposed was 450 manSv. In 1988, mutton/lamb and goat meat valued at approx. NOK 310 million was saved from condemnation by similar measures, which cost approx. NOK 50 million. The resulting dose level reduction was approx. 200 manSv. The relationship (cost/benefit ratio) between the overall cost of the measures taken to reduce radioactivity levels in food and the dose level reduction achieved was acceptable.
[The effect of iodine-131 on the binding characteristics of sex and thyroid hormones by blood plasma proteins in children with a functional thyroid disorder as a result of the accident at the Chernobyl Atomic Electric Power Station]
In studying characteristics of specific interaction of estradiol-, testosterone- and thyroid-binding blood globulins with the corresponding ligands in children from Gomel Province with endemic swelling of the thyroid gland (degrees I and II) affected by iodine-131 revealed were a reduced cooperativity in estradiol and T-3 binding and a halved affinity to androgens and thyroids as compared to healthy controls. In addition, there was a drastic decline in the binding capacity of estradiol- and testosterone-binding globulins in the blood plasma. The endemic thyroid gland swelling is supposed to be due to sexual malfunction in teenagers.
[The functional status of the hypophyseal-adrenal cortical adaptation system in children in Byelarus living under the action of low doses of radiation after the accident at the Chernobyl Atomic Electric Power Station]
The analysis of the status of sympatho-adrenal and hypophysis-adrenal medulla systems of adaptation in children living in territories contaminated by radionuclides was carried out. A decrease in the catecholamine level in children's urine and hyperactivity of the hormonal response of adrenal medulla to endogenous ACTH indicated the reduced ability of adaptation and decreased resistance of children's organisms to stress factors of the environment.
[The function of the hypophyseal-thyroid system in the children of Zhitomir Province living in areas polluted by the radionuclides resulting from the accident at the Chernobyl Atomic Electric Power Station]
A study of 1167 children (age: 7-15 years) inhabiting districts contaminated with radionuclide due to Chernobyl atomic station accident indicates that children with thyroid hyperplasia revealed high requirement and intensity of the peripheral metabolism of thyroid hormones that results finally in relative hormonal deficit (subclinical hypothyroidism) and thyroid hyperplasia. This is a sequel of maximum functional tension of the thyroid with impending breakdown of adaptation and this should be considered as a pathological process requiring correction, i.e. presence of subclinical hypothyroidism in children with thyroid hyperplasia requires substitution therapy with thyroid hormones.
A total of 878 children from the regions with unfavourable radiation situation were investigated in varying periods after the catastrophe. The data obtained were compared with the results of the study of 317 children from "pure" regions. Morphological, metabolic and ultrastructural changes were detected in blood cells of the children from radioactively contaminated regions after the Chernobyl catastrophe. A tendency to normalization of these parameters was noted in the time course of the post-catastrophe period. No clear relationship was established between the dose and effect. However, significant correlations between the severity of disorders in blood cells and the intensity of free-radical processes in the body were recorded.