The article analyses the historical development of ecotoxicology as a young interdisciplinary branch of environmental sciences that uses the entire arsenal of knowledge of natural and exact sciences to create its theoretical framework, terms, tasks, and research methods. The paper describes the achievements, current trends and actual directions of development of ecotoxicology considering their theoretical and practical significance. Nowadays, ecotoxicology has formed a set of data on effects and behaviors of ecotoxicants in populations and communities of terrestrial and aquatic ecosystems. This set of data are at the heart of the theoretical foundation of the doctrine on functioning of biosystems under ecotoxicological stress, assessment of systems conditions by bioindication and bioassay techniques, approaches to develop of ecotoxicants regulation within the framework of the concept of acceptable environmental impact on ecosystems. Special attention is paid to multi-vector nature of ecotoxicological research, its cooperation with other areas of science and technology and contribution to the solution of environmental, economic and political challenges of our time.

This article presents the results of measurement of the toxicity of soils with a specific activity of Cs137 in the range of 3.3 × 102 to 1.3 × 106 Bq/kg; the flux density of β-particles and dose rate of γ-radiation on the surface of a bulk sample were 5.4–192.7 imp/s/cm2 and 0.2–2.7 µSv/h, respectively. The forms of toxicity were detected in a solid-phase biotest with Allium cepa L., which simulated the situation of external irradiation of dividing cells in contact with soil. The toxic effect was assessed relative to the control as mitotoxicity by the decrease in the mitotic index and as genotoxicity based on the induction of chromosomal aberrations, taking into account the contribution of the clastogenic effect. The value of the mitotic index in a series of biotests with contaminated soil decreased to 8.6 ± 1.1–14.6 ± 2.3

The article deals with issues related to the development of radioecology as an independent scientific discipline. The achievements of past years and the studies that are currently being carried out, as well as promising areas of development in this area are analyzed. A corrected periodization of the stages of development of radioecology is proposed, taking into account the experience accumulated to date in the field of this discipline. At the initial stage (1895–1929), empirical material was collected; at the first stage (1930–1960), the theoretical foundation was laid and radioecology was formed as an independent discipline; at the second stage (1961–1990), intensive development of radioecology was noted; and, at the third stage (1991–2010), there was progressive development of radioecology; the fourth—modern—stage of the development of radioecology is in the beginning of the 21st century (2011–present). For each stage, the main scientific achievements and evolution of ideas in the field of radioecology are considered. It is postulated that, at present, the development of this discipline is associated with the further improvement of world nuclear technologies, the elimination of the consequences of a number of radiation incidents (the accident at the Fukushima nuclear power plant in 2011), the revision of the concept of radiation protection of the environment and a number of other provisions. Particular attention is paid to forest radioecology, one of the most important main areas of this science.

A comparative analysis of the methods for studying the radionuclide speciation in the soil based on the fractionation of their compounds associated with different soil components is given. Data are given on the physicochemical nature of the forms of the main environmentally significant technogenic and natural radionuclides in the soils contaminated when testing nuclear weapons as a result of accidents and incidents at radiation hazardous objects, mining and processing of mineral resources. The effect of environmental factors, such as the properties of the radionuclide and soil, the type of radioactive fallout, and the time since they entered the soil, on radionuclide speciation is considered. It was demonstrated that the experimental data on the radionuclide speciation are a theoretical basis for estimating and predicting their mobility in the soil, accessibility for plants, and substantiation of measures for the rehabilitation of contaminated soils.

An algorithm has been developed for the simulation model of carbon behavior in herbaceous communities of various types, both autonomous and as a part of complex phytocenoses. The influence of external factors is taken into account, such as solar radiation, precipitation, air temperature, clouds, and wind speed. The dynamics of soil moisture level and temperature are reproduced. The algorithm can be modified, depending on the discreteness of consideration of the simulated processes. The algorithm is tested in modeling the dynamics of the phytomass of a community of ground elder ( Aegopodium podagraria L.) that is dominant in the herbaceous cover of the ground elder oak grove on dark-gray forest soil. The EcoGrass model is used to conduct numerical experiments to study the impact of the potential global climate change and consumption of phytomass by animals on the productivity of this community. Threshold values of influence factors have been determined upon reaching which the normal functioning of the community is disrupted.

Lanthanides as a separate group of metals geochemically belong to rare earth elements (REEs). For a long time, they have not received proper attention of researchers, whose interest was focused on other harmful environmental pollutants. However, the importance of REEs for modern technologies along with significant gaps in the knowledge about their effects on living organisms has changed the situation. Thanks to the active interest of researchers, a fairly large body of data on REEs in various areas has been accumulated, including their chemical and physical properties, their potential in engineering and instrumentation, their content in various natural objects, effects on human health, and interaction with other living organisms at the cellular level. This review analyzes and generalizes the new information about REEs as a relevant ecological factor with a special focus on the sources of REEs, specific features in their behavior in the soil, the effects of their interaction with plants, their manifestation, and putative mechanisms at the cellular level. The economic importance of plants to humans as well as their role for the entire biosphere as primary producers and their ability to be among the first ecosystem components that respond to negative changes requires focusing on these issues. The purpose of this review is to emphasize the research aspects that need a deeper insight, in particular, the soil–plant interaction and the effect of REEs on plant cell division.

The simulation model of seasonal dynamics of 137Cs in the components of the oak forest ecosystem EcoradOak_CS_FW has been further developed, which now includes first- and second-order consumers. The radiocesium redistribution is modeled in a full-scale food web of a forest ecosystem of the soil–vegetation–herbivores–predator type. The algorithm used in the model allows us to take into account the effects of the soil, meteorological, phenological, and physiological factors on the behavior of radionuclide in the food web and predict radiological situations under various conditions of radioactive fallout. Data obtained with the model on the contamination of animals with radiocesium are used to calculate the dynamics of the internal dose. The results of modeling can be used in the rationing of forest products of deciduous forests. The model is also applicable to the study of potassium redistribution in the trophic chain of a deciduous forest ecosystem.

Some aspects of the application of simulation modeling of radionuclide behavior in food chains of land ecosystems are discussed. A model of behavior of 137Cs in the soil–vegetation–herbivores–predators system is described. The results of modeling, including the calculation of the dynamics of the dose load on animals, are presented. It is shown that according to the simplified Chernobyl scenario of the radiological situation, dose loads on herbivores are significantly lower than on predators. In general, the main contribution to the dose load in animals during the first ten years is made by external irradiation. Then, the external and internal dose loads become approximately equal.

Статья знакомит читателя с основами использования имитационного моделирования в радиоэкологии. Приведено несколько примеров имитационных радиоэкологических моделей разного уровня, иллюстрирующих возможности метода. Модели позволяют исследовать процессы поведения радионуклидов в экосистемах, прогнозировать развитие радиоэкологической ситуации при различных сценариях выпадений, осуществлять реконструкцию радиоэкологических процессов, недостаточно изученных входе радиационных инцидентов прошлого, рассчитывать динамику дозовой нагрузки на компоненты экосистем и человека. Обсуждаются некоторые проблемы применения имитационного моделирования в радиоэкологии.

Examples of the use of different types of chromosome aberrations as diagnostic indicators to solve the practical problems of radioecology were considered. The classifications of the chromosome aberrations used to estimate the clastogenic effect of factors of radiation and chemical nature according to the results of cytogenetic studies with uniform staining of the chromosomes were analyzed. Some terminological inconsistency and ambiguity when designating various types and categories of chromosome aberrations, reflecting the clastogenic effect, was detected. It was demonstrated that this inconsistency can complicate the use of such cytogenetic indices in radioecological practice. According to the results of the Allium test using a digital imaging system, original microimages demonstrating the configurations of aberrant chromosomes used in classifications were obtained.

Various food additives are being produced and consumed by population in greater and greater quantities and risks of probable toxic effects exerted by them are growing as well.These additives frequently occur in various combinations in food products and the environment, they can be consumed for a long period of time and produce hazardous mutagenic and carcinogenic effects.Therefore, it is extremely vital to assess combined impacts exerted by food additives so that their safety would be proven.There are certain advantages related to vegetative test-systems and cytogenetic analysis procedures for biological tests data when it comes to screening for toxic and mutagenic effects produced by chemicals.Allium-test which applies Allium cera bulb onion roots as a test-object is quite distinctive.When compared with other tests that employ animals and various cell cultures, this test turns out to be less complicated and costly and more sensitive as well.Our research goal was to examine influences exerted by such artificial sweeteners as aspartame and sucralose on living weight gain and mitotic anomalies frequency in apical meristem cells in Allium cera bulb onion roots.We also assessed a synergy effect caused by combined exposure to both these chemicals.We detected that aspartame caused a significant decrease in root living weight against the control while there were no toxic effects caused by sucralose.Maximum toxicity was detected when a test-system was exposed to both artificial sweeteners together and it was considered to result from the above mentioned synergy effect.Chromosome aberrations frequency in test samples differed insignificantly from the control but we also detected authentic changes in chromosome anomalies spectrum in root meristem cells.Disorders in chromosome disjunction and anomalies in the mitotic apparatus were the most frequently registered ones.

The possibility of using the VERT_MIG algorithm in simulation models of the vertical migration of radionuclides in soil is discussed. The algorithm was successfully used to develop models of 137 Cs and 90 Sr migration for radioactive contamination of different soils as a result of the accidents at the Chernobyl and Fukushima-1 nuclear power plants. The modeling results are given. Prospects for further use of this algorithm and some aspects of using imitation modeling in this area are discussed.

Lanthanum (La) and cerium (Ce) are one of the most abundant rare earth elements (REEs). In spite of quite extensive studying of the effects of these lanthanides on biota, some contradictions remain in the results. Also little is known about the effect of lanthanum and cerium on plant cells and their mitotic cycle, especially in soils. In this study, the effects of La and Ce in solutions and soil samples on root growth, mitotic index (MI) and frequency of aberrant cells (FAC) were assayed using one of the most convenient objects for testing of cytotoxicity - onion Allium cepa L. Bulbs were germinated on media containing La and Ce in concentrations 0-200 mg/l and 0-50 mg/l respectively for solutions and 0-200 mg/kg for soil samples. After 5 days of germination in solutions, a significant decrease in root elongation and MI in apical meristem cells are shown. We have also observed an increase in the number of cells with aberrations at 50 mg/l La and Ce concentration. The number of observed stickiness and disturbed metaphase has increased significantly. Soil samples turned out to be less toxic compared to the solutions probably due to the decreased availability of REEs. In spite of this, significant cytotoxicity of soil samples containing the highest concentration of La and Ce (200 mg/kg) is observed. The latter may indicate the importance of considering the cytotoxicity of soils containing high lanthanides concentrations - in extraction and production areas and actively fertilized fields.