Vol 65, No 2 (2025)

The article provides an overview of the history of development and substantiates the prospects for using radiation nuclear-physical methods to determine the content of chemical elements in environmental and radiobiological studies, as well as in diagnostic and therapeutic approaches to radiation medicine. Based on the results of long-term experimental and clinical studies conducted at the Institute of Medical Radiology of the Academy of Medical Sciences of the USSR (now the A. Tsyb Medical Radiological Research Center), the mechanisms of entry and negative effects of emissions into the environment of various (including radioactive) chemical elements during the operation of nuclear industry enterprises and during radiation accidents are analyzed, and ways to solve the problems are outlined.

Pilots are included in the list of professions with the most serious selection for health reasons, and therefore the standardized mortality ratio (SMR) indexes for them and the corresponding levels of the “Healthy worker effect” (HWE) can be considered as reference, despite the fact that this professional group is exposed to chronic radiation exposure due to cosmic radiation, which includes a significant proportion of protons and neutrons. A systematic review, combined analyzes (by means of samples) and meta-analysis of papers for SMR estimation for all causes and all cancer mortality for pilots were conducted; final samples included 16 and 13 publications. The presence of HWE was judged based on the fact that the upper limit of the 95% confidence interval (CI) for SMR should be <1.0. As a result of the combined analysis and meta-analysis, values for SMR all causes were 0.60 (95% CI: 0.50; 0.69) and 0.57 (95% CI: 0.48; 0.66), respectively, and for SMR all cancer, equal to 0.61 (95 % CI: 0.51; 0.72) and 0.62 (95% CI: 0.52; 0.75). Thus, compared to the general population, pilots have a 40% reduction in mortality from all causes and from all cancers. This is due to the special health of the pilots, as well as their selection, since studies of SMR all causes and SMR all cancer in flight attendants exposed to the same adverse factors (with the possible exception of occupational stress), but not undergoing rigorous selection, did not reveal a single SMR index which would demonstrate the presence of HWE. SMR all causes and SMR all cancer levels for pilots have remained largely unchanged since the 1970s to 2019 of cohort follow-up, despite the fact that during these periods, due to an increase in flight altitude, both the radiation exposure rate and accumulated radiation doses increased. A review of the sources showed that attempts to detect a dose-dependent increase of the translocation rate in pilots (that is, chromosome aberrations – indicators of carcinogenesis) turned out to be untenable. Thus, the radiation factor is unlikely to affect pilot mortality, but hormesis effects, based on SMR data for flight attendants, are unlikely. Comparison of HWE levels for all causes for pilots and nuclear workers found high effects for some cohorts of workers, especially in the early decades (SMR for all causes in the range of 0.3–0.6 for UK and French personnel). Although such a high level of HWE is not characteristic of most nuclear workers, this effect is reproduced over and over again in cohorts from different countries. The fact that nuclear workers can have SMR comparable to the ‘standard’ occupational selection group, i.e. pilots, enhances the image of both the nuclear industry and employment in the nuclear power branch.

Chronic irradiation can have an immune-modifying effect by changing the balance between pro-inflammatory and anti-inflammatory cytokines, which triggers a mechanism of self-sustaining chronic inflammation. According to modern concepts, chronic inflammation plays a significant role in atherosclerosis progression. The purpose of this work is to evaluate the profile of cytokines involved in the pathogenesis of atherosclerosis in workers exposed to chronic radiation.. Two groups were formed for the study: the main group (workers of a radiation-hazardous enterprise who were exposed to chronic radiation) and the controls (residents of Ozersk city without any contact with occupational exposure). The content of cytokines (IL-6, MCP-1, IFNγ, IL-12p70 and IL-17A) in peripheral blood serum was determined by solid-phase ELISA. There were no statistically significant differences in the content of serum cytokines IL-6, IFNy, IL-12p70 and IL-17A. The content of MCP-1 was statistically significantly higher in the main group and in men of the main group when compared with the controls. The content of MCP-1 was statistically significantly higher, and IL-12p70 was statistically significantly lower in the main group with diseases caused by atherosclerosis than in the control group. Workers of radiation-hazardous enterprises with atherosclerosis-related diseases who have been exposed to chronic radiation have changes in the content of pro-inflammatory cytokines that can contribute to the progression of the disease.

For the first time, the neurobiological effects of the combined action of four key factors of interplanetary flight, simulated in a ground experiment – prolonged residence in hypomagnetic environment, synchronous exposure to prolonged gamma irradiation and simulated microgravity (antiorthostatic suspension) and irradiation of the head with 12C carbon ions – were investigated. It was discovered that hypomagnetic conditions aggravates the effects of the other three factors, which are discussed in our previous works, further increasing excitation. It was shown that the typological characteristics of the experimental animals make a certain contribution to these processes, which, in particular, can be seen in the metabolism of monoamines in key brain structures, especially in the dopaminergic system.

Cold plasma and solutions treated with it are widely used in various fields of medicine. Biomedical effects of cold plasma are primarily associated with the generation of active forms of oxygen and nitrogen. The CAPCO cold plasma source (GPI RAS) generates hydrogen peroxide, nitrogen oxide (II), nitrite ions and nitrate ions in an aqueous solution. Hydrogen peroxide is formed through the Fenton reaction – two-electron reduction of the oxygen molecule. The use of a plasma discharge in an argon flow reduces the generation of hydrogen peroxide compared to atmospheric plasma and eliminates the formation of nitrogen derivatives. The amount of oxidation reaction products initiated by argon plasma is 30% less than that of atmospheric plasma. It is recommended to use direct piezo discharge in air to produce activated solutions used in medicine.

Experiments to study the morphological features of the choroid plexus of the ventricles of the brain were performed on Wistar rats of reproductive age, which were divided into 3 groups of 7 animals: 1 – control and 2 and 3 – chronic irradiation (absorbed doses – 5 and 50 cGy). Irradiation was carried out using a Foton-1 installation from a 137Cs source. The experiments were carried out on anesthetized animals. For analysis, histological preparations of serial sections of the lateral ventricles of the brain were used. To assess the volume of the lateral ventricles, sections were selected where the cross-sectional area was maximum. The following morphofunctional rearrangements were recorded: a decrease in the relative volume of the choroid plexuses, as well as the fraction of cells in the plexuses, a decrease in the height of epithelial cells, swelling of cells, erasure of their contours, vacuolization of the cytoplasm. An increase in the volume fraction of blood vessels and a relatively tight fit of individual loops of blood vessels with each other with phenomena of disorganization were observed. Areas of dystrophic changes not only in the choroid plexus, but also in the brain substance have been recorded. The conducted studies indicate that chronic γ-radiation affects the morphological characteristics of the choroid plexus of the ventricles of the brain and expands the understanding of the effect of low-intensity ionizing radiation on the brain, which can be a potential risk factor leading to plexus dysfunction and disruption of liquor dynamics and blood supply.

Data on the distribution of ¹³⁷Cs and ¹³⁴Cs in the main components (forest litter, upper layers of the mineral part of the soil, elements of the aboveground phytomass of woody plants) of pine plantations in the Belarusian sector of the 30 kilometer zone around the Chernobyl nuclear power plant 8 years after the emergency radioactive fallout are presented. Using dosimetric models based on the integration of the dose function of a point radiation source and the numerical solution of the radiation transfer equations, calculations of the absorbed dose rate of external gamma radiation at a height of 1 m above the surface of the forest floor from the radiation of radionuclides contained in the studied components were performed. Satisfactory convergence of the results of calculation and measurement of dose rate in pine plantations has been established. It is shown that different methods for calculating the dose rate from external gamma radiation of radionuclides contained in the same components of biogeocenosis allow us to obtain comparable results. The determining contribution to the formation of the radiation dose rate of ¹³⁷Cs and ¹³⁴Cs located in the forest floor and 2 upper soil layers of the mineral part of the soil has been established, the contribution of elements of the aboveground phytomass of woody plants does not exceed 2.5%.