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Babich TL, Popova NM, Sokolova DS, Perepelov AV, Safonov AV, Nazina TN. Microbial and Monosaccharide Composition of Biofilms Developing on Sandy Loams from an Aquifer Contaminated with Liquid Radioactive Waste. Microorganisms 2024; 12:275. [PMID: 38399679 PMCID: PMC10892373 DOI: 10.3390/microorganisms12020275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
The development of microbial biofilms increases the survival of microorganisms in the extreme conditions of ecosystems contaminated with components of liquid radioactive waste (LRW) and may contribute to the successful bioremediation of groundwater. The purpose of this work was to compare the composition of the microorganisms and the exopolysaccharide matrix of the biofilms formed on sandy loams collected at the aquifer from a clean zone and from a zone with nitrate and radionuclide contamination. The aquifer is polluted from the nearby surface repository for liquid radioactive waste (Russia). The phylogenetic diversity of prokaryotes forming biofilms on the sandy loams' surface was determined during 100 days using high-throughput sequencing of the V4 region of the 16S rRNA genes. Scanning electron microscopy was used to study the development of microbial biofilms on the sandy loams. The ratio of proteins and carbohydrates in the biofilms changed in the course of their development, and the diversity of monosaccharides decreased, depending on the contamination of the sites from which the rocks were selected. The presence of pollution affects biofilm formation and EPS composition along with the dominant taxa of microorganisms and their activity. Biofilms establish a concentration gradient of the pollutant and allow the microorganisms involved to effectively participate in the reduction of nitrate and sulfate; they decrease the risk of nitrite accumulation during denitrification and suppress the migration of radionuclides. These biofilms can serve as an important barrier in underground water sources, preventing the spread of pollution. Pure cultures of microorganisms capable of forming a polysaccharide matrix and reducing nitrate, chromate, uranyl, and pertechnetate ions were isolated from the biofilms, which confirmed the possibility of their participation in the bioremediation of the aquifer from nonradioactive waste components and the decrease in the radionuclides' migration.
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Affiliation(s)
- Tamara L. Babich
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow 119071, Russia; (T.L.B.); (D.S.S.)
| | - Nadezhda M. Popova
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow 119071, Russia; (N.M.P.); (A.V.S.)
| | - Diyana S. Sokolova
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow 119071, Russia; (T.L.B.); (D.S.S.)
| | - Andrei V. Perepelov
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 119991, Russia;
| | - Alexey V. Safonov
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow 119071, Russia; (N.M.P.); (A.V.S.)
| | - Tamara N. Nazina
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow 119071, Russia; (T.L.B.); (D.S.S.)
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Videvall E, Burraco P, Orizaola G. Impact of ionizing radiation on the environmental microbiomes of Chornobyl wetlands. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 330:121774. [PMID: 37178954 DOI: 10.1016/j.envpol.2023.121774] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/21/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023]
Abstract
Radioactive contamination has the potential to cause damage to DNA and other biomolecules. Anthropogenic sources of radioactive contamination include accidents in nuclear power plants, such as the one in Chornobyl in 1986 which caused long-term radioactive pollution. Studies on animals within radioactive zones have provided us with a greater understanding of how wildlife can persevere despite chronic radiation exposure. However, we still know very little about the effects of radiation on the microbial communities in the environment. We examined the impact of ionizing radiation and other environmental factors on the diversity and composition of environmental microbiomes in the wetlands of Chornobyl. We combined detailed field sampling along a gradient of radiation together with 16 S rRNA high-throughput metabarcoding. While radiation did not affect the alpha diversity of the microbiomes in sediment, soil, or water, it had a significant effect on the beta diversity in all environment types, indicating that the microbial composition was affected by ionizing radiation. Specifically, we detected several microbial taxa that were more abundant in areas with high radiation levels within the Chornobyl Exclusion Zone, including bacteria and archaea known to be radioresistant. Our results reveal the existence of rich and diverse microbiomes in Chornobyl wetlands, with multiple taxonomic groups that are able to thrive despite the radioactive contamination. These results, together with additional field and laboratory-based approaches examining how microbes cope with ionizing radiation will help to forecast the functionality and re-naturalization dynamics of radiocontaminated environments.
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Affiliation(s)
- Elin Videvall
- Department of Ecology, Evolution and Organismal Biology, Brown University, Providence, RI, 02912, USA; Institute at Brown for Environment and Society, Brown University, Providence, RI, 02912, USA; Center for Conservation Genomics, Smithsonian Conservation Biology Institute, 20013, Washington, DC, USA; Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 75236, Uppsala, Sweden
| | - Pablo Burraco
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 75236, Uppsala, Sweden; Doñana Biological Station, Spanish Research Council (EBD-CSIC), 41092, Sevilla, Spain
| | - Germán Orizaola
- IMIB-Biodiversity Research Institute (Univ. Oviedo-CSIC-Princip. Asturias), 33600, Mieres, Asturias, Spain; Zoology Unit, Department of Biology of Organisms and Systems, University of Oviedo, 33071, Oviedo, Asturias, Spain.
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Mijnendonckx K, Rogiers T, Giménez Del Rey FJ, Merroun ML, Williamson A, Ali MM, Charlier D, Leys N, Boon N, Van Houdt R. PrsQ 2, a small periplasmic protein involved in increased uranium resistance in the bacterium Cupriavidus metallidurans. JOURNAL OF HAZARDOUS MATERIALS 2023; 444:130410. [PMID: 36413896 DOI: 10.1016/j.jhazmat.2022.130410] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Uranium contamination is a widespread problem caused by natural and anthropogenic activities. Although microorganisms thrive in uranium-contaminated environments, little is known about the actual molecular mechanisms mediating uranium resistance. Here, we investigated the resistance mechanisms driving the adaptation of Cupriavidus metallidurans NA4 to toxic uranium concentrations. We selected a spontaneous mutant able to grow in the presence of 1 mM uranyl nitrate compared to 250 µM for the parental strain. The increased uranium resistance was acquired via the formation of periplasmic uranium-phosphate precipitates facilitated by the increased expression of a genus-specific small periplasmic protein, PrsQ2, regulated as non-cognate target of the CzcS2-CzcR2 two-component system. This study shows that bacteria can adapt to toxic uranium concentrations and explicates the complete genetic circuit behind the adaptation.
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Affiliation(s)
- Kristel Mijnendonckx
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Tom Rogiers
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Francisco J Giménez Del Rey
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium; Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Mohamed L Merroun
- Campus Fuentenueva, Department of Microbiology, University of Granada, Granada, Spain.
| | - Adam Williamson
- Center for Microbial Ecology and Technology, UGent, Ghent, Belgium.
| | - Md Muntasir Ali
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Daniel Charlier
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Natalie Leys
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Nico Boon
- Center for Microbial Ecology and Technology, UGent, Ghent, Belgium.
| | - Rob Van Houdt
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
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Rogiers T, Claesen J, Van Gompel A, Vanhoudt N, Mysara M, Williamson A, Leys N, Van Houdt R, Boon N, Mijnendonckx K. Soil microbial community structure and functionality changes in response to long-term metal and radionuclide pollution. Environ Microbiol 2021; 23:1670-1683. [PMID: 33415825 PMCID: PMC8048617 DOI: 10.1111/1462-2920.15394] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/09/2020] [Accepted: 01/04/2021] [Indexed: 12/20/2022]
Abstract
Microbial communities are essential for a healthy soil ecosystem. Metals and radionuclides can exert a persistent pressure on the soil microbial community. However, little is known on the effect of long‐term co‐contamination of metals and radionuclides on the microbial community structure and functionality. We investigated the impact of historical discharges of the phosphate and nuclear industry on the microbial community in the Grote Nete river basin in Belgium. Eight locations were sampled along a transect to the river edge and one location further in the field. Chemical analysis demonstrated a metal and radionuclide contamination gradient and revealed a distinct clustering of the locations based on all metadata. Moreover, a relation between the chemical parameters and the bacterial community structure was demonstrated. Although no difference in biomass was observed between locations, cultivation‐dependent experiments showed that communities from contaminated locations survived better on singular metals than communities from control locations. Furthermore, nitrification, a key soil ecosystem process seemed affected in contaminated locations when combining metadata with microbial profiling. These results indicate that long‐term metal and radionuclide pollution impacts the microbial community structure and functionality and provides important fundamental insights into microbial community dynamics in co‐metal‐radionuclide contaminated sites.
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Affiliation(s)
- Tom Rogiers
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.,Center for Microbial Ecology and Technology (CMET), UGent, Ghent, Belgium
| | - Jürgen Claesen
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Axel Van Gompel
- Biosphere Impact Studies, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Nathalie Vanhoudt
- Biosphere Impact Studies, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Mohamed Mysara
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Adam Williamson
- Center for Microbial Ecology and Technology (CMET), UGent, Ghent, Belgium
| | - Natalie Leys
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Rob Van Houdt
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
| | - Nico Boon
- Center for Microbial Ecology and Technology (CMET), UGent, Ghent, Belgium
| | - Kristel Mijnendonckx
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium
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Shuryak I. Review of microbial resistance to chronic ionizing radiation exposure under environmental conditions. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 196:50-63. [PMID: 30388428 DOI: 10.1016/j.jenvrad.2018.10.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 10/21/2018] [Indexed: 06/08/2023]
Abstract
Ionizing radiation (IR) produces multiple types of damage to nucleic acids, proteins and other crucial cellular components. Nevertheless, various microorganisms from phylogenetically distant taxa (bacteria, archaea, fungi) can resist IR levels many orders of magnitude above natural background. This intriguing phenomenon of radioresistance probably arose independently many times throughout evolution as a byproduct of selective pressures from other stresses (e.g. desiccation, UV radiation, chemical oxidants). Most of the literature on microbial radioresistance is based on acute γ-irradiation experiments performed in the laboratory, typically involving pure cultures grown under near-optimal conditions. There is much less information about the upper limits of radioresistance in the field, such as in radioactively-contaminated areas, where several radiation types (e.g. α and β, as well as γ) and other stressors (e.g. non-optimal temperature and nutrient levels, toxic chemicals, interspecific competition) act over multiple generations. Here we discuss several examples of radioresistant microbes isolated from extremely radioactive locations (e.g. Chernobyl and Mayak nuclear plant sites) and estimate the radiation dose rates they were able to tolerate. Some of these organisms (e.g. the fungus Cladosporium cladosporioides, the cyanobacterium Geitlerinema amphibium) are widely-distributed and colonize a variety of habitats. These examples suggest that resistance to chronic IR and chemical contamination is not limited to rare specialized strains from extreme environments, but can occur among common microbial taxa, perhaps due to overlap between mechanisms of resistance to IR and other stressors.
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Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University, 630 West 168(th) street, VC-11-234/5, New York, NY, 10032, USA.
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Safonov AV, Babich TL, Sokolova DS, Grouzdev DS, Tourova TP, Poltaraus AB, Zakharova EV, Merkel AY, Novikov AP, Nazina TN. Microbial Community and in situ Bioremediation of Groundwater by Nitrate Removal in the Zone of a Radioactive Waste Surface Repository. Front Microbiol 2018; 9:1985. [PMID: 30190715 PMCID: PMC6115527 DOI: 10.3389/fmicb.2018.01985] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 08/07/2018] [Indexed: 12/26/2022] Open
Abstract
The goal of the present work was to investigate the physicochemical and radiochemical conditions and the composition of the microbial community in the groundwater of a suspended surface repository for radioactive waste (Russia) and to determine the possibility of in situ groundwater bioremediation by removal of nitrate ions. Groundwater in the repository area (10-m depth) had elevated concentrations of strontium, tritium, nitrate, sulfate, and bicarbonate ions. High-throughput sequencing of the V3-V4/V4 region of the 16S rRNA gene revealed the presence of members of the phyla Proteobacteria (genera Acidovorax, Simplicispira, Thermomonas, Thiobacillus, Pseudomonas, Brevundimonas, and uncultured Oxalobacteraceae), Firmicutes (genera Bacillus and Paenibacillus), and Actinobacteria (Candidatus Planktophila, Gaiella). Canonical correspondence analysis suggested that major contaminant - nitrate, uranium, and sulfate shaped the composition of groundwater microbial community. Groundwater samples contained culturable aerobic organotrophic, as well as anaerobic fermenting, iron-reducing, and denitrifying bacteria. Pure cultures of 33 bacterial strains belonging to 15 genera were isolated. Members of the genera Pseudomonas, Rhizobium, Cupriavidus, Shewanella, Ensifer, and Thermomonas reduced nitrate to nitrite and/or dinitrogen. Application of specific primers revealed the nirS and nirK genes encoding nitrite reductases in bacteria of the genera Pseudomonas, Rhizobium, and Ensifer. Nitrate reduction by pure bacterial cultures resulted in decreased ambient Eh. Among the organic substrates tested, sodium acetate and milk whey were the best for stimulation of denitrification by the microcosms with groundwater microorganisms. Injection of these substrates into the subterranean horizon (single-well push-pull test) resulted in temporary removal of nitrate ions in the area of the suspended radioactive waste repository and confirmed the possibility for in situ application of this method for bioremediation.
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Affiliation(s)
- Alexey V. Safonov
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
- V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Moscow, Russia
| | - Tamara L. Babich
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Diyana S. Sokolova
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Denis S. Grouzdev
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Tatiyana P. Tourova
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Andrey B. Poltaraus
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Elena V. Zakharova
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
- V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Moscow, Russia
| | - Alexander Y. Merkel
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander P. Novikov
- V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Moscow, Russia
| | - Tamara N. Nazina
- V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Moscow, Russia
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
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Daňo M, Viglašová E, Galamboš M, Rajec P, Novák I. Sorption behaviour of pertechnetate on oxidized and reduced surface of activated carbon. J Radioanal Nucl Chem 2017. [DOI: 10.1007/s10967-017-5532-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Galamboš M, Daňo M, Viglašová E, Krivosudský L, Rosskopfová O, Novák I, Berek D, Rajec P. Effect of competing anions on pertechnetate adsorption by activated carbon. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-3953-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Ding C, Feng S, Cheng W, Zhang J, Li X, Liao J, Yang Y, An Z, Luo S, Yang J, Tang J, Liu N. Biosorption behavior and mechanism of thorium on Streptomyces sporoverrucosus dwc-3. J Radioanal Nucl Chem 2014. [DOI: 10.1007/s10967-014-3110-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Lu X, Zhou XJ, Wang TS. Mechanism of uranium(VI) uptake by Saccharomyces cerevisiae under environmentally relevant conditions: batch, HRTEM, and FTIR studies. JOURNAL OF HAZARDOUS MATERIALS 2013; 262:297-303. [PMID: 24041822 DOI: 10.1016/j.jhazmat.2013.08.051] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Revised: 08/18/2013] [Accepted: 08/19/2013] [Indexed: 06/02/2023]
Abstract
Biosorption is of significance for the safety evaluation of high-level nuclear wastes repositories and remediation of radioactive contamination places. Quantitive study and structural characterization of uranium uptake by both live and heat-killed Saccharomyces cerevisiae at environmentally relevant uranium concentration and with different ionic strengths were carried out. Kinetic investigation showed the equilibrium reached within 15 min. In equilibrium studies, pH shift towards neutral indicated release of hydroxyl ions. pH was the most important factor, which partly affected electrostatic interaction between uranyl ions and S. cerevisiae surface. The high ionic strength inhibited biosorption capacity, which can be explained by a competitive reaction between sodium ions and uranyl ions. Heat killing process significantly enhanced biosorption capacity, showing an order of magnitude higher than that of live cells. High resolution transmission electron microscopy (HRTEM) coupled with energy dispersive X-ray (EDX) showed needle-like uranium-phosphate precipitation formed on the cell walls for both live and heat-killed cells. Besides, dark-field micrographs displayed considerable similar uranium-phosphate precipitation presented outside the heat-killed cells. The phosphate released during heat-killing process. FTIR illustrated function groups hydroxyl, carboxyl, phosphate, and amino groups played important role in complexation with uranium.
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Affiliation(s)
- Xia Lu
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, Gansu Province 730000, PR China.
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Hejl AM, Ottmar RD, Timothy Jannik G, Eddy TP, Rathbun SL, Commodore AA, Pearce JL, Naeher LP. Radionuclide activity concentrations in forest surface fuels at the Savannah River Site. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2013; 115:217-226. [PMID: 23262410 DOI: 10.1016/j.jenvman.2012.10.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 09/19/2012] [Accepted: 10/08/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND/OBJECTIVE A study was undertaken at the United States Department of Energy's Savannah River Site (SRS), Aiken, South Carolina to investigate radionuclide activity concentrations in litter and duff from select areas at SRS. Litter (i.e. vegetative debris) and duff (i.e. highly decomposed vegetative debris) can often be the major fuels consumed during prescribed burns and have potential to release radiological contaminants into the environment. METHODS Repeated samples from 97 locations were collected systematically across SRS and analyzed for radionuclide activity. Radionuclide activity concentrations found in litter and duff were compared. As spatial trends were of interest, spatial distributions of radionuclide activity concentrations found in litter and duff and spatial dependency amongst the data were explored. RESULTS (7)Be, (40)K, and (137)Cs showed statistically significant proportional differences between litter and duff samples. Duff sample concentrations for (137)Cs (p < 0.0001) and (40)K (p = 0.0015) were statistically higher compared to litter samples. (7)Be activity concentrations were statistically higher in litter as compared to duff (p < 0.0001). For (40)K litter and duff samples, spatial correlation tests were not significant at p = 0.05 and the maps did not indicate any apparent high concentrations centered near possible radionuclide sources (i.e. SRS facilities). For (7)Be litter samples, significant spatial correlation was calculated (p = 0.0085). No spatial correlation was evident in the (7)Be duff samples (p = 1.0000) probably due to small sample size (n = 7). (137)Cs litter and duff samples showed significant spatial correlations (p < 0.0001 and p < 0.0001, respectively). CONCLUSIONS To date, few studies characterize radionuclide activity concentrations in litter and duff, and to our knowledge none present spatial analysis. Key findings show that across SRS, (137)Cs is the primary radionuclide of concern, with the highest number of samples reported above MDC in litter (51.4%) and duff samples (83.2%). However, (137)Cs litter and duff spatial trends in the maps generated from the kriging parameters do not appear to directly link the areas with higher activity concentrations with SRS facilities. The results found herein provide valuable baseline monitoring data for future studies of forest surface fuels and can be used to evaluate changes in radioactivity in surface fuels in the southeast region of the U.S.
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Affiliation(s)
- Anna M Hejl
- The University of Georgia, College of Public Health, Department of Environmental Health Science, 206 Environmental Health Science Building, Athens, GA 30602-2102, USA
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Wiebke J, Weigand A, Weissmann D, Glorius M, Moll H, Bernhard G, Dolg M. Combined Computational and Experimental Study of Uranyl(VI) 1:2 Complexation by Aromatic Acids. Inorg Chem 2010; 49:6428-35. [DOI: 10.1021/ic902496u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jonas Wiebke
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Anna Weigand
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Daniel Weissmann
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Maja Glorius
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Henry Moll
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Gert Bernhard
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Michael Dolg
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
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