[An assessment of relative contribution of DNA reparation and glutathione-dependent pathway of detoxification in response of Chlorella algae to uranium].

Toxicity of 238U (as uranyl nitrate) in the range of 0.04-84 micromol/L for Chlorella (Chlorella vulgaris Beijerink) was investigated. The best approximation for relationship between the toxic effect in Chlorella and 238U Concentrations is observed using the hormetic Brain-Cousens model.

[Evaluation of the partial contribution of naturally occurring radionuclides and nonradioactive chemically toxic elements in formation of biological effects within the Vicia cracca population inhabiting the area contaminated with uranium-radium production wastes in the Komi Republic].

The site contaminated with uranium-radium production wastes in the Komi Republic was studied. The activity concentration of naturally occurring radionuclides (226Ra, 228Th, 238U, 230Th, 232Th, 210Po, and 210Pb), as well as concentrations of nonradioactive chemically toxic elements (Pb, Zn, Cu, As, V, Mo, Sr, Y, and Ba) in the soil samples from the experimental site is 10-183 times higher than reference levels. A chronic exposure to alpha-emitters and nonradioactive chemically toxic elements causes adverse effects in tufted vetch (Vacia cracca L.

[Radiation risk assessment for plant reference species (Pinus sylvestris and Vicia cracca) from the area of radium production waste storage].

The risk of an enhanced level of radionuclides of the uranium and thorium decay series in the environment for reference plant species (Pinus sylvestris and Vicia cracca) was assessed. 238U, 230Th, 226Ra, 210Po, 232Th and 228Th concentration factors for plants were found to be lower than one. The aboveground parts of Vicia cracca sampled from the area of the radium production waste storage mainly accumulated 22Ra, Pinus sylvestris branches--210Pb, 226Ra and 210Po.

[Regularities of lateral distribution of uranium and thorium decay series radionuclides in the anthropogenically changed soils from the area of radium production waste storage].

Cartographical investigations of the territory of radium production waste storage has shown some changes in lateral differentiation of radionuclides of uranium and thorium decay series to occur during 27 years (1981-2008). Those changes are caused mostly by flat denudation typical for fluvial terrace. At present radionuclides of uranium and thorium decay series are concentrated mostly in flood lands and relief depressions.

Effects of long-term chronic exposure to radionuclides in plant populations.

The results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hairgrass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate the effects of long-term chronic exposure to radionuclides are discussed. Plant populations growing in areas with relatively low levels of pollution are characterized by an increased level of both cytogenetic disturbances and genetic diversity. Although ionizing radiation causes primary damage at the molecular level, there are emergent effects at the level of populations, non-predictable from the knowledge of elementary mechanisms of cellular effects formation.