Resuspension and atmospheric transport of radionuclides due to wildfires near the Chernobyl Nuclear Power Plant in 2015: An impact assessment.

In April and August 2015, two major fires in the Chernobyl Exclusion Zone (CEZ) caused concerns about the secondary radioactive contamination that might have spread over Europe. The present paper assessed, for the first time, the impact of these fires over Europe. About 10.9 TBq of (137)Cs, 1.5 TBq of (90)Sr, 7.8 GBq of (238)Pu, 6.3 GBq of (239)Pu, 9.4 GBq of (240)Pu and 29.7 GBq of (241)Am were released from both fire events corresponding to a serious event. The more labile elements escaped easier from the CEZ, whereas the larger refractory particles were removed more efficiently from the atmosphere mainly affecting the CEZ and its vicinity. During the spring 2015 fires, about 93% of the labile and 97% of the refractory particles ended in Eastern European countries. Similarly, during the summer 2015 fires, about 75% of the labile and 59% of the refractory radionuclides were exported from the CEZ with the majority depositing in Belarus and Russia. Effective doses were above 1 mSv y(-1) in the CEZ, but much lower in the rest of Europe contributing an additional dose to the Eastern European population, which is far below a dose from a medical X-ray.

[Features of behavioral reactions of chronically irradiated mice in the raised crosswise labyrinth with various genetically determined radiosensitivity and possibilities of their modification by the fungal biopolymer complex].

Structural elements of the central nervous system--neurons, along with the higher neuroendocrine structures and the hypothalamus centres, show high sensitivity to a chronic action of low doses of ionizing radiation (IR) in view of their extreme enrichment by phospholipids and intensive supply by oxygen, creating favorable conditions for the development of oxidizing stress. Stressful influences cause negative emotions in the behaviour of animals manifested as fear or uneasiness. The study represents the results of comparative research into the behavioral reactions characterized by uneasiness in the Balb/c and C57bl/6 mice exposed to a chronic irradiation at low doses. The chitin-melanin-glucan complex from fungi Fomes fomentarius (ChMG) was approved as an adaptive agent. It has been shown that under identical conditions, deposition levels of radionuclides 137Cs and 90Sr are raised in mice with IR hypersensitivity--line Balb/c, in comparison with less radio sensitive mice--line C57bl/6. Simultaneously, Balb/c mice were observed to exhibit the signs of a more anxious behaviour in the new environment. Chronic external and internal radiation exposure to rare ionizing radiation at low doses promotes strengthening of anxiety and phobic reactions in mice with IR hypersensitivity. The use of ChMG in animals neutralized the increase in anxiety and phobic reactions after a prolonged irradiation, thus indicating the presence in ChMG of the anxiolitic activity along with the above mentioned powerful radiosorbent, antioxidant, gene protective and immunomodulatory properties.

[Radioecological problems of aquatic ecosystems of the Chernobyl exclusion zone].

The results of radioactive contamination dynamics in the main components of aquatic ecosystems and the absorbed dose rate for hydrobionts within the Chernobyl accident exclusion zone was analysed. Some cytogenetical and haematological effects of long-term irradiation on aquatic organisms as well as damage of higher aquatic plants by parasitic fungi and gall-producing arthropods were considered.

[The main radionuclides and dose formation in fish of the Chernobyl NPP exclusion zone].

The results of the researches of spices-specificity, accumulation dynamics and distribution of 90Sr, of 137Cs and of transuranic elements in fish of the Chernobyl NPP exclusion zone are analysed. The data of estimations of absorbed doze rate from incorporated radionuclides for pray fish and predatory species are given. For the fish from the lake of the left-bank floodplain of the Pripyat River the increase of 90Sr specific activity is registered which is presumably connected with the dynamics of the physical-chemical forms of the radionuclide in soils and their wash out in water bodies from the catchment basin. Now about 90% of internal dose rate of fish from closed aquatic ecosystems within the Chernobyl NPP exclusion zone is caused by 90Sr incorporation.