タグ「90Sr」
Title: Levels and trends of radioactive contaminants in the Greenland environment
Author: Henning Dahlgaard, Mats Eriksson, Sven P. Nielsen, Hans Pauli Joensen
Reference: Science of the Total Environment. Sep2004, Vol. 331 Issue 1-3, p53-67. 15p.
DOI: http://dx.doi.org/10.1016/j.scitotenv.2004.03.023
Keywords: Caesium-137; Strontium-90; Technetium-99; Plutonium-239-240; Polonium-210; Greenland; Environmental radioactivity
Abstract: Levels of radioactive contaminants in various Greenland environments have been assessed during 1999–2001. The source of 137Cs, 90Sr and 239,240Pu in terrestrial and fresh water environments is mainly global fallout. In addition, the Chernobyl accident gave a small contribution of 137Cs. Reindeer and lamb contain the largest observed 137Cs concentrations in the terrestrial environment—up to 80 Bq kg−1 fresh weight have been observed in reindeer. Due to special environmental conditions, 137Cs is transferred to landlocked Arctic char with extremely high efficiency in South Greenland leading to concentrations up to 100 Bq kg−1 fresh weight. In these cases very long ecological half-lives are seen. Concentrations of 99Tc, 137Cs and 90Sr in seawater and in marine biota decrease in the order North-East Greenland and the coastal East Greenland current>South-West Greenland>Central West Greenland and North-West Greenland>Irmiger Sea∼Faroe Islands. The general large-scale oceanic circulation combined with European coastal discharges and previous contamination of the Arctic Ocean causes this.
URL: http://www.sciencedirect.com/science/article/pii/S0048969704002025
Title: Accumulation and potential dissolution of Chernobyl-derived radionuclides in river bottom sediment.
Author: Sanada, Yukihisa / Matsunaga, Takeshi / Yanase, Nobuyuki / Nagao, Seiya / Amano, Hikaru / Takada, Hideshige / Tkachenko, Yuri
Reference: Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine, 56 (5), p.751-760, May 2002
Keywords: radionuclides, river, 137Cs, 90Sr
Abstract: Areas contaminated with radionuclides from the Chernobyl nuclear accident have been identified in Pripyat River near the Chernobyl Nuclear Power Plant. The river bottom sediment cores contained 137Cs (10(5)-10(6) Bq/m2) within 0-30 cm depth, whose concentration is comparable to that in the ground soil in the vicinity of the nuclear power plant (the Exclusion Zone). The sediment cores also accumulated 90Sr (10(5) Bq/m2), (239,240)Pu (10(4) Bq/m2) and 241Am (10(4)Bq/m2) derived from the accident. Several nuclear fuel particles have been preserved at 20-25 cm depth that is the peak area of the concentrations of the radionuclides. These inventories in the bottom sediments were compared with those of the released radionuclides during the accident. An analysis using a selective sequential extraction technique was applied for the radionuclides in the sediments. Results suggest that the possibility of release of 137Cs and (293,240)Pu from the bottom sediment was low compared with 90Sr. The potential dissolution and subsequent transport of 90Sr from the river bottom sediment should be taken into account with respect to the long-term radiological influence on the aquatic environment.
URL: http://www.ncbi.nlm.nih.gov/pubmed/11993951?dopt=Abstract
Title: Radiation contamination after the chernobyl nuclear accident and the effective dose received by the population of Croatia
Author: Lokobauer, Nevenka / Franić, Zdenko / Bauman, Alica / Maračić, Manda / Cesar, Dobroslav / Senčar, Jasminka
Reference: Journal of Environmental Radioactivity, 41 (2), p.137-146, Nov 1998
doi: 10.1016/S0265-931X(97)00006-4
Keywords: Radioactive contamination, Croatia, humans, 137Cs, 90Sr
Abstract: Because of the Chernobyl nuclear accident which led to enhanced deposition of all fission products, contamination of the human environment in the Republic of Croatia was much higher than in the previous two decades. The paper deals with the investigation of deposition and contamination by fission product radionuclides (137Cs and 90Sr, in particular), especially within the human food chain. Its aim was to determine differences in contamination levels resulting from the Chernobyl accident and from large-scale atmospheric nuclear weapon tests. For the year following the Chernobyl accident, the radiation doses received from external and internal exposures were estimated for 1-year old infants, children at the age of 10-years and adults. The corresponding annual effective doses were 1·49, 0·93 and 0·83 mSv, respectively. The paper also gives data on the yearly intakes of 137Cs and 90Sr in foods and the corresponding effective doses received by the population of Croatia over many years from the global fallout following nuclear weapons testing and the Chernobyl accident.
URL:http://www.franic.info/radovi/NLokobauer_Radiation_Contamination_after_Chernobyl.pdf
Title: Association of dissolved radionuclides released by the Chernobyl accident with colloidal materials in surface water
Author: Matsunaga, Takeshi / Nagao, Seiya / Ueno, Takashi / Takeda, Seiji / Amano, Hikaru / Tkachenko, Yu.
Reference: Applied Geochemistry, 19 (10), p.1581-1599, Oct 2004
doi:10.1016/j.apgeochem.2004.02.002
Keywords: radionuclides, 137Cs, 90Sr, Plutonium, colloids
Abstract: The association of dissolved 90Sr, 239,240Pu and 241Am with natural colloids was investigated in surface waters in the Chernobyl nuclear accident area. A 4-step ultrafiltration (UF) study (239,240Pu and 76% of 241Am are distributed in colloids of the two size fractions larger than 10 kDa (nominal molecular weight limit of the filter, NMWL), while 90Sr was found exclusively (85–88%) in the lowest molecular size fraction below 1 kDa (NMWL) for the Sahan River water at the highly contaminated area close to the Chernobyl Nuclear Power Plant (ChNPP). Consistent results were obtained by 2-step fractionation (larger than and smaller than 10 kDa (NMWL)) for river and lake waters including other locations within about 30 km away from ChNPP. It is likely that Pu and Am isotopes were preferentially associated with dissolved organic matter of high molecular size, as suggested by the fact that (i) only a few inorganic elements (Mg, Ca, Sr, Si, Mn, Al) were found in the colloidal size ranges, and (ii) the positive correlation between dissolved organic C (DOC) concentrations and UV absorbance at 280 nm, a broad absorption peak characteristic of humic substances (HS) was found. A model calculation on the complexation of Pu and Am with HS as an organic ligand suggests that the complexed form could be dominant at a low DOC concentration of 1 mgC L−1, that is commonly encountered as a lower limit in fresh surface water. The present results suggest the general importance of natural organic colloids in dictating the chemical form of actinides in the surface aquatic environment.
URL: http://www.experts.scival.com/kanazawa/pubDetail.asp?id=2942700456&o_id=36
Title: Radiation-induced impacts on the degradation of 2,4-D and the microbial population in soil microcosms
Author: Niedrée, Bastian / Vereecken, Harry / Burauel, Peter
Reference: Journal of Environmental Radioactivity, 115, p.168-174, Jan 2013
doi: 10.1016/j.jenvrad.2012.08.008
Keywords: Mineralization; 2,4-D, Dichlorophenoxyacetic acid; 137Cs, 90Sr, 14C; Chernobyl
Abstract: ► We observed the impact of contamination with Cs-137 and Sr-90 on soil functions. ► The contamination went up to 30-fold of that in the 30 km Chernobyl zone. ► The radioactive contamination inhibited the 2,4-D mineralization temporary. ► The bacterial and fungal community structure was also affected.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X12002159
- Title: A comparison of 90Sr and 137Cs uptake in plants via three pathways at two Chernobyl-contaminated sites.
Author: Malek, M A / Hinton, T G / Webb, S B
Reference: Journal of environmental radioactivity, 58 (2-3), p.129-141, Jan 2002
doi: http://dx.doi.org/10.1016/S0265-931X(01)00062-5
Keywords: Foliar absorption; Resuspension; Soil loading; 137Cs; 90Sr; Root uptake; Risk
Abstract: Foliar absorption of resuspended 90Sr, root uptake and contamination adhering to leaf surfaces (i.e. soil loading) were compared at two Chernobyl-contaminated sites, Chistogalovka and Polesskoye. Although foliar absorption of resuspended 90Sr was quantifiable, its contribution amounted to less than 10% of the plants’ total, above-ground contamination.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X01000625
- Title: “Blind” testing of models for predicting the 90Sr activity concentration in river systems using post-Chernobyl monitoring data
Author: Sasina, N. V.; Smith, J. T.; Kudelsky, A. V.; Wright, S. M.
Reference: Journal of Environmental Radioactivity, 92 (2). 63-71.
doi: 10.1016/j.jenvrad.2006.09.007
Keywords: 90Sr, Model, Chernobyl, River, Pripyat, Weapons testing, Catchment, Runoff
Abstract: Two different models for predicting the time-dependent mobility of 90Sr in river systems have been evaluated using post-Chernobyl monitoring data for five large Belarusian rivers (Dnieper, Pripyat, Sozh, Besed and Iput) in the period between 1990 and 2004. The results of model predictions are shown to be in good agreement (within a factor of 5) with the measurements of 90Sr activity concentration in river waters over a long period of time after the accident.
URL: http://nora.nerc.ac.uk/606/
- Title: Impact of Scots pine (Pinus sylvestris L.) plantings on long term 137Cs and 90Sr recycling from a waste burial site in the Chernobyl Red Forest
Author: Thiry, Yves / Colle, Claude / Yoschenko, Vasyl / Levchuk, Svjatoslav / Van Hees, May / Hurtevent, Pierre / Kashparov, Valery
Reference: Journal of Environmental Radioactivity, 100 (12), p.1062-1068, Dec 2009
doi: 10.1016/j.jenvrad.2009.05.003
Keywords: Radiocaesium; Radiostrontium; Forest; Biological cycle; Waste; Remediation; Afforestation
Abstract: Plantings of Scots pine (Pinus sylvestris L.) on a waste burial site in the Chernobyl Red Forest was shown to greatly influence the long term redistribution of radioactivity contained in sub-surfaces trenches. After 15 years of growth, aboveground biomass of the average tree growing on waste trench no.22 had accumulated 1.7 times more 137Cs than that of trees growing off the trench, and 5.4 times more 90Sr.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X0900109X
- Title: Strontium-90 and caesium-137 activity concentrations in bats in the Chernobyl exclusion zoneAuthor: Gashchak, Sergey / Beresford, Nicholas Anthony / Maksimenko, Andrey / Vlaschenko, Anton S
Reference: Radiation and environmental biophysics, 49 (4), p.635-644, Nov 2010
doi: 10.1007/s00411-010-0322-0
Keywords:
Abstract: Bats are a protected species and as such may be an object of protection in radiological assessments of the environment. However, there have previously been only few radioecological studies of species of bats. In this paper, results for >140 measurements of (90)Sr and (137)Cs in 10 species of bats collected within the Chernobyl zone are presented. There was some indication of a decreasing transfer of (90)Sr with increasing deposition, although this was inconsistent across species and explained little of the observed variability. There was no difference between male and female bats in the transfer (expressed as the ratio of whole-body activity concentrations to those in soil) of either radionuclide. There was considerable variability in transfer across all species groups. At two sites where there were sufficient data, Eptesicus serotinus was found to have higher transfer than other species.
URL: http://www.ncbi.nlm.nih.gov/pubmed/20714905?dopt=Abstract
- Title: FREQUENCY DISTRIBUTIONS OF 90SR AND 137CS CONCENTRATIONS IN AN ECOSYSTEM OF THE ‘RED FOREST’ AREA IN THE CHERNOBYL EXCLUSION ZONE
Author: Gaschak, Sergey P / Makliuk, Yulia A / Maksimenko, Andrey M / Bondarkov, Mikhail D / Chizhevsky, Igor / Caldwell, Eric F / Jannik, G Timothy / Farfán, Eduardo B
Reference:Health physics, 101 (4), p.409-415, Oct 2011
doi:
Keywords: Chernobyl, bioaccumulation factor, 90Sr, 137Cs
Abstract: In the most highly contaminated region of the Chernobyl Exclusion Zone: the ‘Red Forest’ site, the accumulation of the major dose-affecting radionuclides (90Sr and 137Cs) within the components of an ecological system encompassing 3,000 m2 were characterized. The sampled components included soils (top 0-10 cm depth), Molina caerulea (blue moor grass), Camponotus vagus (carpenter ants) and Pelobates fuscus (spade-footed toad).
URL: http://www.ncbi.nlm.nih.gov/pubmed/21878766?dopt=Abstract
