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The paper is devoted to determination of α-emitting radionuclides of 238, 239 + 240Pu and 241Am in liver, lungs, muscular and bone tissues of the boars on the territory of the Belarusian part of the ChNPP exclusion zone. It is shown that the content of Pu and Am isotopes in boar organs and tissues decreases in the following order: liver > bone tissues > lungs ≥ muscular tissues. The results received allow evaluation of penetration of 238, 239 + 240Pu and 241Am through the biological chain "soil-ration-organs and tissues". It is calculated that 1.7% of a boar's ration falls on the soil getting into the stomach with food. Translocation and accumulation coefficients characterizing the transfer of radionuclides through the chain "soil-vegetation-organs and tissues" were calculated. The conclusion about accumulation of Pu in the boar's body is made.

In this paper, some final results of 25-year investigations carried out in Scientific Centre for Radiation Medicine and Burns MH RA (SCRMB) on the Armenian cohort of the Chernobyl accident consequences liquidators are shown. These results show that health conditions of the liquidators became worse during the whole observation period. A considerable development of both pathological states atypical of radiation damages and diseases, which may be considered as radiation-induced ones, was determined. Rise of the sickness rate of almost all organism systems, first of all, nervous, cardiovascular, respiratory and digestive ones, was observed. In 70% of liquidators the main disease was primarily detected after working on CNPP. In the intervening years, the average number of diagnoses per 1 liquidator increased from 1.5 in 1987 to 7-8 in the recent time. In addition to the detected diseases, particular functional shifts in neuropsychological and vegetative status of the liquidators were observed. The overwhelming majority of them have increased tonicity of the sympathetic vegetative nervous system, asthenic and depressive syndromes occurring in the form of weakness, somnolence, mood instability, mental capacity decrease, and memory defects. In the paper, the results of investigations aimed at clarification of changes in biological aging processes of the liquidators and assessment of their "life quality" features in terms of physical, psychical and social welfare are considered. Biological aged-related passportization in a definite part of liquidators elucidated an accelerated aging rate. The studies were performed with the help of SF-36 inquirer and indicated that health status aggravation of the liquidators also affected their life satisfaction. The "life quality" indices of the liquidators significantly concede the overall average standards by both physical health and psychical and social welfare scales.

In this paper the results of the Chernobyl accident investigation 5-10 and 24 years after are summarized. The genomic instability, adaptive response formation, genome damage and oxidative status have been investigated. The studies were performed on cells in culture, mice, children and adults living in contaminated areas and liquidators. On cells in culture after exposition in the accident zone and culturing thereafter in laboratory conditions the cell proliferative activity decrease; the late cell death, the frequency of cells with micronuclei and giant cells increasing have been observed. In the progeny of exposed cells the enhancement of radiosensitivity has been noticed. So we can suppose that in cultured cells exposition in the zone of the accident the genomic instability is induced which results in many disturbances. At the organism level in mice exposed in the Chernobyl zone the radiosensitivity increase and the decrease of endotheliocytes density in brain tissue has been observed. On the stimulated by PHA blood lymphocytes of children the increase of the frequency of cells with micronuclei more than 2 time have been noticed. In all groups investigated, the decrease of individuals with significant adaptive response was observed. In children and adults inhabitants the increase of radiosensitivity after low dose of irradiation has been noticed. 24-year after the accident it was discovered that in liquidators lymphocytes the frequency of cells with micronuclei, with chromosome type aberrations, with DNA double strand breaks have been increased; the reactive oxygen species (ROS) were decreased in comparison with the control population. We can suppose that genomic instability induced in residents of contaminated regions and liquidators long after the accident results in the genetic apparatus damage, radiosensitivity enhancement, hypoxia that represent risk factors and increase the probability of tumour and non-tumour diseases. The development of these pathological processes may happen in much more remote periods.

In this paper, we analyze the results of long-term investigations of 137Cs accumulation in the specimens of fish of the highest trophic level, pike and pike perch, from the reservoirs suffered as a result of the ChNPP. Annual, seasonal and age peculiarities of accumulation of the 137Cs specific activity in the predatory fish from the Kiev reservoir and Teterev River were considered. It was shown, that during the whole time of radioecological investigations the pike was characterized by the higher level of 137Cs specific activity muscles in comparison with other predatory fish, in particular, pike perch. Intimated relationship between seasonal, age and sexual differences in 137Cs accumulation in fish organisms and types of feeding were revealed.

The paper presents the dynamics and the current state of radioactive contamination with 137Cs of low--running Kozhanovskoe lake situated in Bryansk region. Semi-empiric assessment of the current radiation state based on the analysis of dynamics of contamination of Kozhanovskoe lake with 137Cs corresponds satisfactory to experimental data. Integral 137Cs inventories were estimated for the main components of the lake, including water, bottom sediments and aquatic vegetation for the period of 2005-2007.

Health effects as a result of the accident at the Chernobyl nuclear power plant occurred in 1986 are considered in the paper. Wrong prognosis of the health effects with respect to mortality and morbidity among the population exposed to low radiation doses is shown. Proven increase in thyroid cancer cases among people who were children aged from 0 to 18 at the time of the accident is shown. Linear relationship between thyroid cancer cases and dose to thyroid ranged from 0.2 to 4.0 Gy is considered. An additional absolute risk of thyroid cancer in children varies in the range 1.9-2.6 cases per 10(4) person-year Gy. During the fifteen years following the accident no cases of acute and chronic radiation sickness have been revealed because the population living in contaminated areas received low radiation doses. Also, exposures to low radiation doses did not result in excess of malignant tumors among population. In some cases the outcomes of acute radiation sickness were as follows: radiation damages to the skin, cancer cataracts, development of oncopathology.

The formation of aerosols over the radioactive polluted areas results from some natural and industrial factors. In this paper physico-chemical characteristics of secondary aerosols generated by the Chernobyl accident are presented. The results of monitoring of the aerosol from traffic, dust storms and forest fires in 30-km zone of the Chernobyl nuclear power plant and other regions are compared. Some methodical aspects of the sampling and analyses of aerosols are considered. The recommendations for choice of the personal respirators are given.

The paper presents the results of retrospective dose estimations in a number of Chernobyl victims by different approaches to the analysis of dicentric distribution in peripheral lymphocytes in blood samples taken a long time after the accident. Retrospective dose estimations are compared with dose estimates in the same individuals made immediately after the accident by dicentric frequencies.

The role of external beta-radiation as one of the major radiation factors effected persons involved in recovery operations (liquidators) after the accident at the Chernobyl nuclear power plant is considered. The paper uses the data of discriminate individual dosimetric monitoring of beta- and gamma-radiation for different groups of liquidators and experimentally received dose distribution in tissue equivalent material in the places of carrying out work. The results obtained by calculation were also used. It was established that experimentally determined ratios of beta-radiation doses to gamma-radiation doses have a good correlation with estimates resulted by calculation. It allowed the authors to use these estimates and individual gamma-radiation dose distribution for drawing histograms of individual beta-radiation dose distribution for open parts of skin, for lens, and gonads in cases of liquidators involved in building "sarcophagus". The obtained estimates of individual doses in the near surface tissue and organs exceeds significantly exposure levels for the whole body. This fact should draw the special attention to the rise in the number of radiation-induced cancer and cataracts.

The paper presents the general results from the 10-year (1986-1996) studies on radioecology and radiobiology conducted in the region affected by radiation after the accident at the Chernobyl NPP. The regularities of radionuclide migration along the trophic chains, as well as effect of ionising radiation on biota in its habitat are described. The protective measures are reported aimed at mitigating consequences of the accident for the environment. The paper also presents the main findings of studies on agricultural radioecology with taking into account the importance of radionuclide turnover in agrosphere and implementation of countermeasures in the agro-industrial production.

The paper presents the data on cytogenetic studies of 663 children inhabited radionuclide contaminated territories of Bryansk Province. Statistically significant difference with control was observed only for the territory with the highest radioactive contamination level of 137Cs (1000 kBq/m2). For two other territories with lesser contamination (100 and 700 kBq/m2) the rate of chromosome aberrations is nearly the same and does not differ significantly from control one. No difference in the level of cytogenetic damage was discovered for children affected by radiation pre- or postnatally.