The use of the aquatic plant Elodea canadensis to assess the effects of low-dose gamma irradiation.

Responses of cytogenetic and growth endpoints of the aquatic plant Elodea canadensis were studied using the plants collected from non-contaminated control areas of the Yenisei River and exposed to external γ-radiation for 11-13 days in the laboratory. Elodea canadensis was exposed to 0.5-25 mGy/day γ-radiation dose rates from a Cs source.

Experimental assessment of Am accumulation in Carassius gibelio from amphipods.

Accumulation of dietary Am in freshwater omnivorous fish (Carassius gibelio) was studied aiming to estimate the distribution and retention of Am in the fish body. Amphipods labeled with Am served as a food item. From 0.

Comparative Study of Plutonium and Radiocaesium Content in the Muscle of Fish of the Yenisey River.

This work reports the first data on the content of plutonium (Pu) in the muscle tissues of the Northern pike (Esox lucius) and the Siberian dace (Leiciscus baicalensis) inhabiting the middle reaches of the Yenisey River in the vicinity of the radioactive discharge site. An increase in the content of Pu and radiocaesium (Cs) in pike muscles followed an increase in the volume of controlled discharges of these radionuclides to the Yenisey in 2018. The content of Pu in the muscles of pike (2-11 mBq/kg dry weight) and dace (1-4 mBq/kg dry weight) of the Yenisey fall within the range of values obtained by other authors for the ichthyofauna from water bodies contaminated with radioactive discharges from nuclear power plants and spent nuclear fuel processing plants.

Со-60 as a time marker to date sediment layers and estimate sediment transport distances during the 2006 flood event on the Yenisei River.

The study of bottom sediments collected from the Yenisei River downstream of the Mining-and-Chemical Combine (MCC) conducted from 2006 to 2016 revealed increased concentrations of Co, which was present in dispersed form and in the form of radioactive microparticles, in the upper core layers. The increase in Co activity concentration occurred when the 2006 extreme flood on the Yenisei washed away the radionuclide-containing soil from the riverbank at the MCC. The Cs/Co ratio in the upper layers of bottom sediments after the 2006 flood varied between 0.

Effect of Gamma Radiation on Cytogenetic and Growth Endpoints of Allium cepa Seedlings in Long-Term Experiments.

The effect of γ-radiation on the growth and cytogenetic endpoints of Allium cepa L. seedlings in a long period after irradiation in absorbed doses from 1.0 to 10.

A comparative study of biota and sediments as monitors of plutonium in the Yenisei River (Siberia, Russia).

MOX-fuel production and spent nuclear fuel reprocessing started recently at the Mining-and-Chemical Combine (MCC, Zheleznogorsk, Russia) have caused an increase in controlled releases of plutonium to the Yenisei River. In this study, we analyzed time-dependent trends of plutonium (Pu and Pu) in biota and bottom sediments of the Yenisei during 2008-2019, to estimate comparatively the potential of abundant representatives of biota as bio-monitors of contamination of the Yenisei by plutonium. Gamma-emitting radionuclides ( K; Co; Cs; Eu; Am) were measured in environmental samples of the Yenisei as well.

Long-term trends and speciation of artificial radionuclides in two submerged macrophytes of the Yenisei River: A comparative study of Potamogeton lucens and Fontinalis antipyretica.

Long-term trends of artificial radionuclides, from 2003 to 2018, in two abundant species of macrophytes, shining pondweed, Potamogeton lucens, and water moss, Fontinalis antipyretica, have been analyzed to estimate the indicative reliability of these two species as biomonitors of radioactive contamination in a river system and to quantify the decrease in the content of artificial radionuclides in the Yenisei River. Time-dependent trends of artificial radionuclides in the biomass of these species were similar, resulting in estimates of effective half-lives for Mn, Co, Co, Zn, Cs, and Eu similar for both species. Concentrations of artificial radionuclides in biomass of shining pondweed and water moss correlated with annual discharges of the radionuclides to the Yenisei at different levels of significance, and the strongest (R > 0.

The long-term effects of γ-radiation on the growth of plants.

Purpose: The purpose of this study was to assess the long-term effects of gamma-radiation, including low-dose radiation, on growth parameters of onion () seedling roots 6-10 days after irradiation.

Materials And Methods: Onion seedlings were exposed to a Cs gamma source at doses ranging from 0.1 to 10 grays (Gy).

Effects of Gamma-Radiation on DNA Damage in Onion (Allium cepa L.) Seedlings.

The effect of γ-radiation on the level of nuclear DNA damage in onion seedlings (Allium-test) was studied using the comet assay. DNA breaks were first found in cells of onion seedlings exposed to low-dose radiation (≤ 0.1 Gy).

A long-term study of radionuclide concentrations in mushrooms in the 30-km zone around the Mining-and-Chemical Combine (Russia).

Cs concentrations were measured in mushrooms in an area affected by radioactive discharges of the Mining-and-Chemical Combine (MCC) (Rosatom, Russia) in 2002-2017. The sources of radionuclides in the study sites were global fallouts and waterborne and airborne radioactive discharges of the MCC. The mushroom species and showed the highest Cs concentrations (140-7100 Bq kg) for this area.

Biomonitoring of radioactive contamination of the Yenisei River using aquatic plants.

The Yenisei River is contaminated by artificial radionuclides released by one of the Russian facilities producing weapons-grade plutonium (the Mining-and-Chemical Combine, MCC), which has been in operation for 60 years. The paper presents results of long-term monitoring of radionuclide concentrations in six aquatic plant species collected from the 1400 km Yenisei River stretch downstream of the city of Krasnoyarsk. Before the last MCC reactor was shut down (in 2010), up to 30 artificial radionuclides were detected in the plant biomass, and 2 and 5 years after the reactor shutdown, 11 and 3-5 radionuclides, respectively, were detected.

Time-dependent trends of artificial radionuclides in biota of the Yenisei River (Siberia, Russia).

We investigated time-dependent trends of artificial radionuclides in aquatic moss, zoobenthos (amphipods and caddisfly larvae), and three abundant wild fish species (Northern pike, Arctic grayling, and Siberian dace) inhabiting the Yenisei River in the vicinity of the radioactive discharge site in 2007-2015, in a period before and after the shutdown of the last nuclear reactor plant at the Mining-and-Chemical Combine (MCC), which occurred in 2010. From our research, we learned that concentrations of short-lived radionuclides, whose discharges to the Yenisei either stopped or declined after the shutdown of the reactor plant at the MCC (Na, Sc,Cr, Mn, Co, Fe, Co, Zn, Ru, Ce, Eu, Np), decreased in biota samples as well. The ecological half-life (EHL) of Zn (0.

Chromosomal aberrations and micronuclei induced in onion (Allium cepa) by gamma-radiation.

The Allium-test is commonly used to assess genotoxicity of chemical and physical factors. In the present study, the roots of germinating onion (Allium cepa) were exposed to 0.02-13 Gy of γ-radiation.

Cytogenetic Effects of γ-Radiation in Onion (Allium cepa L.) Seedlings.

The effect of γ-radiation on the cytogenetic parameters of root meristem cells of onion seedlings was studied in laboratory experiments (Allium-test). An increase in the overall frequency of chromosomal aberrations and micronucleus frequencies in seedling cells at low γ-radiation doses (≤0.1 Gy) was detected for the first time.

Protein-based fluorescent bioassay for low-dose gamma radiation exposures.

The study suggests an application of a coelenteramide-containing fluorescent protein (CLM-CFP) as a simplest bioassay for gamma radiation exposures. "Discharged obelin," a product of the bioluminescence reaction of the marine coelenterate Obelia longissima, was used as a representative of the CLM-CFP group. The bioassay is based on a simple enzymatic reaction-photochemical proton transfer in the coelenteramide-apoprotein complex.

New data on the effect of ionizing radiation on the growth of the aquatic plant Elodea canadensis in the laboratory.

Toxicological experiments with radioactive bottom sediments and extrinsic γ-irradiation have demonstrated that the growth of common elodea roots is suppressed by irradiation at doses several times lower than the established threshold dose. The effect of γ-irradiation on the growth of elodea stems has not been observed at any dose used. The data obtained show that elodea could be recommended for use as an indicator of biological effects of radiation in the range of low radiation doses.

Gamma irradiation of resting eggs of Moina macrocopa affects individual and population performance of hatchlings.

We investigated the effects of γ-radiation on the survival of resting eggs of the cladoceran Moina macrocopa, on the parameters of the life cycle of neonates hatched from the irradiated eggs and on the performance of the population initiated from irradiated eggs. The study showed that γ-radiation in a range of doses from the background level to 100 Gy had no effect on survival of irradiated eggs. The absorbed dose of 200 Gy was lethal to resting eggs of M.

Exposure of luminous marine bacteria to low-dose gamma-radiation.

The study addresses biological effects of low-dose gamma-radiation. Radioactive Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested.

Low doses of gamma-radiation induce SOS response and increase mutation frequency in Escherichia coli and Salmonella typhimurium cells.

This study addresses use of two bacterial test systems (the Ames test and the SOS chromotest) to estimate the effects of low doses of γ-radiation. The most substantial increases in induction of SOS response and mutation frequencies were observed in the first 24h of exposure to γ-radiation as compared to the cells in the exposure-free control. Gamma-radiation also impaired growth and survival of S.

Genotoxicity assessment of low-level doses of gamma radiation with the SOS chromotest and the Ames test.

This is the first study to present data on the genotoxicity of low γ-irradiation doses for E. coli and S. typhimurium cells obtained using the SOS chromotest and the Ames test.

Age-dependent accumulation of (137)Cs by pike Esox lucius in the Yenisei River.

Age-dependent accumulation of (137)Cs in the muscles and bodies of the pike Esox lucius (aged two to seven years) inhabiting a section of the Yenisei River polluted with artificial radionuclides has been studied. The content of (137)Cs in muscles varied from 0.5 to 7.

The effect of γ-radiation on resting eggs and life cycle of cladoceran Moina macrocopa.

We investigated the effects of γ-irradiation on the survival of resting eggs of the cladoceran Moina macrocopa and on the parameters of the life cycle of neonates hatched from the irradiated eggs. It was shown that γ-irradiation in a wide range of doses (from the background level to 100 Gy) had no effect on survival of eggs and mortality of neonates hatched from the irradiated eggs. However, exceeding the absorbed dose of 40 Gy sharply decreased the reproductive potential of the neonates hatched from irradiated eggs.

Chromosomal abnormalities in roots of aquatic plant Elodea canadensis as a tool for testing genotoxicity of bottom sediments.

Submersed freshwater macrophytes are considered as relevant indicators for use in bulk bottom sediment contact tests. The purpose of this study was to estimate the validity of endpoints of aquatic plant Elodea canadensis for laboratory genotoxicity testing of natural bottom sediments. The inherent level of chromosome abnormalities (on artificial sediments) in roots of E.

Use of the aquatic plant Elodea canadensis to assess toxicity and genotoxicity of Yenisei River sediments.

The toxicity, cytotoxicity, and genotoxicity of bulk sediments from the Yenisei River (Siberia, Russia) were estimated in laboratory bioassays based on several endpoints in the aquatic plant Elodea canadensis. The bottom sediment samples were collected in the Yenisei River upstream and downstream of the sources of chemical and radioactive contamination. The testing revealed different sensitivities of Elodea endpoints to the quality of the bottom sediment: weight of shoots < length of shoots < mitotic index < length of roots < percentage of abnormal cells.