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Sample records for 137cs 40k 210pb

  1. 210Po, 210Pb, 40K and 137Cs in edible wild berries and mushrooms and ingestion doses to man from high consumption rates of these wild foods.

    PubMed

    Gwynn, Justin P; Nalbandyan, Anna; Rudolfsen, Geir

    2013-02-01

    This paper discusses activity concentrations of (210)Po, (210)Pb, (40)K and (137)Cs in edible wild berries and mushrooms collected from Øvre Dividalen national park, Northern Norway and derives committed effective ingestion doses to man based on high consumption rates of these wild foods. Edible wild berries and mushrooms accumulated similar levels of (210)Pb, but mushrooms accumulated higher levels of (210)Po and (40)K than berries. There appears to be a clear difference in the ability of Leccinum spp. of fungi to accumulate (210)Po and/or translocate (210)Po to mushrooms compared to Russula spp. of fungi. Activity concentrations of (137)Cs in edible wild berries and mushrooms from Øvre Dividalen national park reflected the lower levels of fallout of this radionuclide in Northern Norway compared to more central areas following the Chernobyl accident. For mushrooms, ingestion doses are dominated by (210)Po, while for berries, (40)K is typically the main contributor to dose. Based on high consumption rates, ingestion doses arising from the combination of (210)Po, (210)Pb and (40)K were up to 0.05 mSv/a for berries and 0.50 mSv/a for mushrooms. Consumption of such wild foods may result in a significant contribution to total annual doses when consumed in large quantities, particularly when selecting mushrooms species that accumulate high activity concentrations of (210)Po.

  2. Radioisotopes (137Cs, 40K, 210Pb) indicate that cryoturbation processes in Alaskan tussock tundra are accelerated under deeper winter snow: results from short and long-term winter snow depth experiments

    NASA Astrophysics Data System (ADS)

    Blanc-Betes, E.; Sturchio, N. C.; Taneva, L.; Welker, J. M.; Guilderson, T. P.; Poghosyan, A.; Gonzalez-Meler, M. A.

    2010-12-01

    Permafrost soils cover 8.6% of the Earth land area and contain up to 50% of the global soil organic carbon (SOC) pool. Amplified warming in northern latitudes has resulted directly and/or indirectly in multiple structural and functional changes in arctic ecosystems which may lead to strong forcing feedbacks on the climate system. Cryoturbation is a dominant soil forming process in permafrost regions that results to the mixing of soil layers during freeze-thaw cycles, and may increase in rates following global warming. As a result, the active layer of cryoturbated soils can average 62% larger C stocks than those from non-cryoturbated ones. Cryoturbation is a critical overlooked driver of C dynamics in permafrost soils that will likely play a pivotal role in the fate of Arctic soil C under climate change conditions. However, cryoturbation phenomena is difficult to quantify. We measured cryoturbation rates using a multiple isotope approach at Toolik Lake, Alaska, in moist acidic tundra soils from short- and long-term snow addition experiments. Shifts in cryoturbation rates as affected by these manipulations were measured by the relative activity of natural and weapon-derived radioisotopes (e.g. 137Cs, 40K, 210Pb). By tracking the vertical distribution of these fallout and natural radioisotopes in soils and calculating soil diffusion coefficients, we were able to quantify cryoturbation mixing rates and sediment transport mechanisms that operate at multiannual time scales. Our results show an apparent uplift of buried organic matter to the surface as a result of soil thermal insulation and subsequent deepening of the active layer. These results sharply contrast with current notions that cryoturbation in Arctic systems results in net burial of organic matter, resulting in increased C storage at depth. Mechanisms of this mechanical mixing and its effects on C redistribution and storage of organic matter will be presented to shed light on this apparent contradiction.

  3. Distributions of (137)Cs and (210)Pb in moss collected from Belarus and Slovakia.

    PubMed

    Aleksiayenak, Yu V; Frontasyeva, M V; Florek, M; Sykora, I; Holy, K; Masarik, J; Brestakova, L; Jeskovsky, M; Steinnes, E; Faanhof, A; Ramatlhape, K I

    2013-03-01

    In the present work, moss samples collected in Slovakia and Belarus were assayed with respect to gamma-emitting radionuclides. The results for (137)Cs and (210)Pb are discussed. Moss was used for the first time in Belarus, as a biological indicator of radioactive environmental pollution in consequence of the Chernobyl accident in 1986. In Belarus, the maximum activity of (137)Cs was observed in the Gomel region near Mazyr (6830 Bq/kg) and the minimum activity in the Vitebsyevsk Region near Luzhki-Yazno (5 Bq/kg). "Hot spots" were also observed near the towns Borisow and Yuratsishki. The results of measurements of (137)Cs in moss samples collected in 2000, 2006 and 2009 in the same localities of Slovakia are presented and compared with the results of air monitoring of (137)Cs carried out in Slovakia from 1977 until 2010. Measurements of the (210)Pb concentration in moss samples collected over the territory of Slovakia showed, that the median value exceed 2.3 times median value of (210)Pb obtained for Belarus moss. For that reason, the inhalation dose for man from (210)Pb and (137)Cs in Slovakia is more than twice as high as in Belarus, in spite of the initially very high (137)Cs exposure in the latter country.

  4. 7Be, 210Pb and 137Cs concentrations in cloud water.

    PubMed

    Bourcier, L; Masson, O; Laj, P; Paulat, P; Pichon, J-M; Chausse, P; Gurriaran, R; Sellegri, K

    2014-02-01

    Cloud water was sampled during 8 months, in 2008 and 2009, at the puy de Dome high-altitude atmospheric research station (France). The concentrations of (7)Be and (210)Pb, both naturally occurring radionuclides, and (137)Cs of anthropogenic origin, were determined. Those values are useful for a better knowledge of the aftermath cloud deposition and more generally for wet deposition assessment of radionuclides. This is of primary interest in case of a nuclear accident, especially considering (137)Cs deposition, both for high-altitude locations that are regularly embedded by clouds and also for lowlands where fog can occur. The (7)Be and (210)Pb average activity concentrations in cloud water found were 1.9±0.11 mBq m(-3) air and 140±10 μBq m(-3) air, respectively. For (137)Cs, the average concentration was 0.14±0.02 μBq m(-3) air. This very low-level is representative of the long term post-accidental background level. Indeed, for the studied period, the last accidental (137)Cs release was that of Chernobyl accident, in April 1986. To our knowledge this is the first data about (137)Cs reference level determination in cloud water. The comparison between cloud water and rain water concentrations showed a ratio cloud/rain ranging between 3.4 and 8.1, in agreement with previous studies performed on inorganic compounds. Scavenging efficiencies of aerosols by cloud droplets were also calculated with the additional aerosol concentrations routinely measured at the station and were quite low (0.13-0.40) compared to what has previously been observed for inorganic soluble ions.

  5. Using 137Cs and 210Pb ex measurements to estimate soil redistribution rates on semi-arid grassland in Mongolia

    NASA Astrophysics Data System (ADS)

    Kato, H.; Onda, Y.; Tanaka, Y.

    2010-02-01

    In this study, two small experimental catchments were selected in semi-arid grassland in Mongolia. The Kherlen-bayan Ulaan (KBU) catchment has been subjected to intensive grazing as a wintering shelter for domestic livestock animals, and the number of livestock animals in the Baganuur (BGN) catchment has been increasing over the last few decades. The rates and patterns of soil erosion within the catchments were estimated based on cesium-137 ( 137Cs) and lead-210 ( 210Pb ex) inventories in bulk soil core samples. The medium-term (~ 40 years) soil erosion rates based on the 137Cs measurements indicated that annual soil loss from the KBU catchment was approximately three times greater than that from the BGN catchment. The 137Cs-derived rates and patterns of soil erosion indicated that soil in the KBU catchment was susceptible to surface erosion, with facilitated transport of eroded sediment to the catchment outlet. The 210Pb ex-derived soil erosion rates were generally greater than those derived from 137Cs in both catchments. If we assume that the soil erosion rate has been increasing with increasing domestic livestock numbers, the most plausible explanation is that the 210Pb ex-derived estimates represent recent increases in soil erosion. Furthermore, the 210Pb ex/ 137Cs inventory ratio showed a tendency to increase with downslope distance on the eroded hillslope in the BGN catchment. Assuming that the increase in inventory ratio is a result of constant fallout input of 210Pb ex on the eroded sediment during its transportation along the hillslope, the 210Pb ex inventory may not be suitable to estimate soil erosion rates at sites where downslope movement of sediment is slow. Further discussion regarding interpretation of 210Pb ex-derived soil loss is required, and the applicability of the 210Pb ex technique on semi-arid hillslopes remains to be determined.

  6. [Using 137Cs and 210Pb(ex) to trace the impact of soil erosion on soil organic carbon at a slope farmland in the black soil region].

    PubMed

    Fang, Hai-Yan; Sheng, Mei-Ling; Sun, Li-Ying; Cai, Qiang-Guo

    2013-07-01

    Soil cores were collected from a 28.5 hm2 slope farmland in the black soil region of Northeast China. Based on the sampled data of 137Cs, 210Pb(ex) and SOC, the potentials of applying 137Cs and 210Pb(ex) for assessing SOC redistribution were evaluated, aimed to approach the impact of soil erosion on soil organic carbon (SOC) in black soil region. At both planar and vertical directions, the 137Cs, 210Pb(ex) and SOC in the farmland had similar distribution patterns. Although there were large planar variations in the 137Cs and 210Pb(ex) areal activities and the SOC stock as affected by soil erosion and deposition, the 137Cs, 210Pb(ex) and SOC had similar changing trends over the landscape. Two depth distribution profiles were also used to study the relations of 137Cs and 210Pb(ex) with SOC. At eroded site, the radioactivities of 137Cs and 210Pb(ex) and the SOC mass fraction did not show large variations in 0-25 cm soil layer, but decreased sharply below 25 cm. For the deposition sample, the radioactivities of 137Cs and 210Pb(ex) in 0-100 cm soil increased firstly and then decreased. The SOC mass fraction also had similar depth distribution pattern in this soil layer. The 137Cs and 210Pb(ex) presented positive linear correlations with the SOC, indicating that 137Cs, 210Pb(ex) and SOC moved with the same physical mechanism in the farmland, and fallout 137Cs and 210Pb(ex) could be used to study spatio-temporal distribution characteristics of SOC in the black soil region under the condition of soil erosion.

  7. Transport and sediment accumulation of sup 210 Pb and sup 137 Cs in two southeast Alaskan fjords

    SciTech Connect

    Sugai, S.F. )

    1991-05-01

    Sediment profiles of {sup 210}Pb and {sup 137}Cs in cores collected at increasing distances form the heads of Smeaton Bay and Boca de Quadra fjords indicate that watersheds influence the inventories of radioisotopes present and that the steep topographies of the fjords enhance sediment redistribution. Episodic deposition of terrestrially derived sediment was responsible for roughly 50% of the {sup 137}Cs and 45% of the {sup 210}Pb inventories in shallower (less than 180 m) locations in Wilson and Bakewell arms of Smeaton Bay. {sup 210}Pb sedimentation rates at shallower sites when corrected for episodic deposition were less than sedimentation rates obtained in the deep basins of the fjords where sediment focusing and increased primary productivity in the overlaying water column occur. Higher fluxes of dissolved Mn from surficial sediments and subsequent reoxidation in the overlying water may have enhanced scavenging of {sup 210}Pb in basin locatons resulting in higher inventories. Episodic events have occured frequently in Smeaton Bay and Boca de Quadra suggesting that steady-state conditions with respect to sedimenting particles can be achieved only when averaged over long time periods approaching the time over which {sup 137}Cs and {sup 210}Pb are useful.

  8. Results of an IAEA inter-comparison exercise to assess 137Cs and total 210Pb analytical performance in soil.

    PubMed

    Shakhashiro, A; Mabit, L

    2009-01-01

    Fallout radionuclides (FRNs) such as (210)Pb and (137)Cs have been widely used to assess soil erosion and sedimentation processes. It is of major importance to obtain accurate analytical results of FRNs by gamma analysis before any data treatment through conversion model and to allow subsequent comparison of erosion and sedimentation rates from different case studies. Therefore, IAEA organized an inter-comparison exercise to assess the validity and reliability of the analytical results of (137)Cs and total (210)Pb using gamma-spectrometry in the various laboratories participating in the IAEA Co-ordinated Research Project on "Assess the effectiveness of soil conservation measures for sustainable watershed management using fallout radionuclides". Reference materials were distributed to 14 participating laboratories and, using a rating system, their analytical results were compared to the reference values assigned. In the case of (137)Cs, the analytical results were satisfactory with 66% of the laboratories producing acceptable results. Only the sample with low (137)Cs activity (2.6+/-0.2Bqkg(-1)) gave less accurate results with more than 25% not acceptable results. The total (210)Pb analysis indicated a clear need for corrective actions in the analysis process as only 36% of the laboratories involved in the proficiency test was able to access total (210)Pb with occurrence (bias 10%). This inter-laboratory test underlines that further inter-comparison exercises should be organized by IAEA or regional laboratories to ensure the quality of the analytical data produced in Member States. As a result of the above-mentioned proficiency test, some recommendations have been provided to improve accurate gamma measurement of both (137)Cs and total (210)Pb. PMID:18760612

  9. Dating of coastal marine sediments: 210Pb versus 137Cs signal on the Danube-influenced Black Sea shelf

    NASA Astrophysics Data System (ADS)

    Friedrich, Jana; Laptev, Gennady

    2010-05-01

    Coastal marine sediments represent a natural archive of pelagic processes, coastal erosion and river discharge of suspended matter. Correct dating of those sediments is a prerequisite for chronological reconstruction of the flux of pollutants and organic matter from the water column to the sediments and hence, the reconstruction of the pollution and eutrophication events. In the reconstruction of the sedimentation history during the pre-industrial and industrial periods, which usually spans the past 100 years, the natural occurring radionuclide 210Pb and the artificial radionuclides 137Cs and 241Am are widely applied tracers. 137Cs is used as an independent time marker for end the atmospheric bomb test fallout in 1963 and the Chernobyl accident in 1986. As the 137Cs signal is often weakened due to its mobility in sediments, 241Am, less mobile than 137Cs and derived from decay the bomb fallout of 241Pu, is used as a second time marker of the 1963 event. The northwestern shelf of the Black Sea has been seriously affected by eutrophication and pollution from the late 1960's to the mid-1990's, largely triggered by Danube River input of nutrients and pollutants. The aim of our study is ultimately to reconstruct the eutrophication history and recycling of nutrients following the deposition of organic matter. The ‘memory effect' of sediment recycling plays a critical role in maintaining eutrophic conditions in enclosed seas such as the Black Sea. Here we present results from sediment cores taken within the Danube River plume on the shallow northwestern shelf of the Black Sea. The cores have been dated in two laboratories to rule out artifacts. The sediment record is repeatedly interrupted by so-called turbidites that consist of stiff clay. The clay horizons display a drop in unsupported 210Pb and 137Cs and a higher signal of supported 210Pb than the non-clay horizons. Below the turbidite, the unsupported 210Pb and 137Cs increase again to values above the turbidite. This

  10. 137Cs and excess 210Pb deposition patterns in estuarine and marine sediment in the central region of the Great Barrier Reef Lagoon, north-eastern Australia.

    PubMed

    Pfitzner, John; Brunskill, Gregg; Zagorskis, Irena

    2004-01-01

    This paper focuses on the distribution of 137Cs and 210Pb(xs) in 51 estuarine and marine sediment cores collected between the Upstart Bay and Rockingham Bay in the Great Barrier Reef Lagoon, north-eastern Australia. Historical records of 210Pb(xs) and 137Cs atmospheric deposition and present day terrestrial inventories in north-eastern Australia are presented. 210Pb(xs) and 137Cs fluxes measured on suspended sediments in the Burdekin River are considered to be a source of recent inputs of these nuclides to the nearshore region of this part of the Great Barrier Reef. Direct correlations between sediment nuclide inventories, maximum detectable depths, and sediment mass accumulation rates (MARs), calculated using both 137Cs and 210Pb(xs), are explored. In relation to inventories of 210Pb(xs), 60% of atmospheric fallout 137Cs appears to be missing from the sediments. The reasons for these differences in two tracers, primarily of atmospheric origin, are discussed in terms of the geochemical properties of these two nuclides. Evidence is presented to support the hypothesis that the 137Cs distribution in these cores can be a useful independent tracer which provides confirmation of MARs calculated from the decay of 210Pb(xs). PMID:15245842

  11. Dry and wet deposition of 7Be, 210Pb and 137Cs in Monaco air during 1998-2010: seasonal variations of deposition fluxes.

    PubMed

    Pham, Mai K; Povinec, Pavel P; Nies, Hartmut; Betti, Maria

    2013-06-01

    Temporal variations of (7)Be, (210)Pb and (137)Cs activity concentrations in precipitation in Monaco from 1998 to 2010 showed that maxima of (7)Be and (210)Pb deposition fluxes coincide with the peaks of precipitation amounts observed in different months of a year, and most of (7)Be and (210)Pb was washout from the atmosphere by precipitation. The seasonal variations were not uniform from year to year, and the amount of precipitation controlled the deposition fluxes of (7)Be and (210)Pb, which was not the case for (137)Cs. The fractional deposition fluxes of (7)Be and (210)Pb in different seasons were in the order fall > spring > winter > summer, while the fractional amount of precipitation followed the order fall > winter > spring > summer. The fractional deposition fluxes of (137)Cs were found in the order spring > fall > summer > winter. The precipitation-normalized deposition fluxes of (7)Be, (210)Pb and (137)Cs were generally higher during summer. The highest (7)Be/(210)Pb activity ratio was observed in 2010, and the smallest one in 2001, following the influence of the modulation of cosmic rays on the production rates of (7)Be in the atmosphere by solar activity. Activity ratios of (7)Be/(210)Pb observed in winter and fall were generally higher than during summer and spring.

  12. Measurements of210Pb,137Cs, organic carbon and trace elements in sediments of the Illinois and Mississippi rivers

    USGS Publications Warehouse

    Cahill, R.A.; Autrey, A.D.

    1987-01-01

    Radiometric dating of sediment accumulations by137Cs and210Pb has been successfully initiated in the Illinois and Mississippi Rivers. Sedimentation rates measured at 13 locations range from 0.7 to 3.6 cm/y. Chemical analysis has been completed for up to 45 major and trace elements in core samples. The upper Illinois River contains higher metal levels than the Mississippi River. The amount of carbon (energy) lost to sediments in large floodplain rivers is estimated between 370 and 4000 g/m2/y. ?? 1987 Akade??miai Kiado??.

  13. Recent lake sedimentation in the middle and lower Yangtze basin inferred from 137Cs and 210Pb measurements

    NASA Astrophysics Data System (ADS)

    Xiang, L.; Lu, X. X.; Higgitt, D. L.; Wang, S. M.

    2002-11-01

    The reduction of water storage capacity in the lakes of the Yangtze basin was an important factor for the disastrous 1998 flooding. This study attempted to quantify sedimentation and its role in the water storage reduction in the middle and lower reaches of the Yangtze basin using the radionuclide of caesium-137 ( 137Cs) and lead-210 ( 210Pb) as tracers. Sixteen cores were taken from eight lakes, including the two largest lakes in the region (Poyanghu and Dongtinghu). The two dating techniques were used in combination to quantify recent sediment accumulation rates and their changes over the last few decades. The 137Cs and 210Pb measurements indicated higher sedimentation rates for Dongtinghu which were consistent with observed severe reduction of water storage capacity. The inferred sedimentation rates for the remaining lakes were lower and did not reflect the perceived rate of severe soil erosion upstream or the substantial water storage reduction. The low sedimentation rates inferred for most lakes tentatively suggest that sediment deposition was not the primary reason for the observed reduction in water storage capacity. Nevertheless, a clear increasing trend in sedimentation rates has been documented for most of the studied lakes over the past few decades. Sedimentation and its role in water storage reduction require further study due to the many problems associated with its quantification such as the post-depositional redistribution of sediments and water exchanges between the Yangtze river and the studied lakes.

  14. Atmospheric flux, transport and mass balance of (210)Pb and (137)Cs radiotracers in different regions of Romania.

    PubMed

    Begy, R Cs; Kovacs, T; Veres, D; Simon, H

    2016-05-01

    This study focuses on the determination of (210)Pb and (137)Cs fluxes from different areas in Transylvania, Romania and on the determination of transport and mass balance within the lacustrine system of Red Lake. In order to achieve this, samples were taken from six different locations (Bihor County area, Ighiel area, Red Lake area, Mluha Peatbog, Mohos Peatbog and Zanoaga Rosie Peat bog in the Semenic Mountains) throughout Romania, these being compared to the values of the Danube Delta area. The activity concentrations of the soil samples were measured by gamma spectrometry (HPGe detector) for both (210)Pbtotal, (210)Pbsup ((226)Ra) and (137)Cs, while peat samples were measured by both alpha ((210)Po) spectrometry (PIPS detectors) as well. The mean value for the (210)Pb flux was measured in the Danube Delta region (42±8Bqm(-2) yr(-1)), while the highest was measured in the Semenic Peatbog (227±54Bqm(-2) yr(-1)); the average being 132±8Bqm(-2) yr(-1). In case of (137)Cs the mean was 298±3Bqm(-2) yr(-1), maximum being 1683±15Bqm(-2) yr(-1) in case of Ighiel area and minimum being 32±1Bqm(-2) yr(-1) in the Danube Delta region. In case of the Red Lake, from the total inventory of 410±23Bqm(-2) yr(-1) in the sediments, the loss by outflows is 100±12Bqm(-2) yr(-1), the catchment to lake transfer factor being 0.84%. PMID:26922393

  15. Evaluation of C accumulation rates, as determined by 137Cs and 210Pb, for a vegetation gradient in central Alaska

    NASA Astrophysics Data System (ADS)

    Manies, K.; Harden, J. W.; Fuller, C. C.; Turetsky, M. R.

    2012-12-01

    Boreal ecosystems comprise a large portion of the world's soil carbon (C) in large part because the rate of biomass production is greater than the rate of decomposition. To aid in our understanding in the C balance of these systems we need to determine soil C accumulation rates in different ecosystems. Here we use 137Cs and 210Pb chronologies to examine the C accumulation rates of a natural vegetation gradient found within the Bonanza Creek LTER of central Alaska. Five ecosystems, located along a ~300-m transect, were dominated by black spruce, low shrubs, tussock grass, Carex sp., or brown moss. Only the black spruce and shrub site are underlain by permafrost. Three soil cores were taken from each site and analyzed for C content. Depth profiles were also measured for 137Cs and 210Pb, dating the soil horizons, allowing us to estimate C accumulation rates. Average unsupported 210Pb inventories (dpm/cm^2) for each ecosystem type were similar. However, unsupported 210Pb activity was found in the mineral soil horizons for the tussock grass site, suggesting that Pb may be mobile in this system. Estimated dates of formation for each horizon, calculated using both the Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) methods, were usually within +/- 5 years for the past 50 years, but deviated more for older, deeper horizons, likely due to uncertainty in defining the unsupported 210Pb inventory. Recent C accumulation rates varied among ecosystem type, with the black spruce sites having the lowest rate of C accumulation and the other ecosystems (not including the tussock grass site) having approximately the same C accumulation rates. Variability within each ecosystem type, however, was high. The short-term accumulation rates found for these ecosystems (44 - 100 gC/m^2/yr) are within the range of values found in some northern studies (i.e., 40-117 gC/m^2/yr; Turunen et. al, 2004), but higher than those reported by others (i.e., 20-30 gC/m^2/yr

  16. Applicability study of using in-situ gamma-ray spectrometry technique for 137Cs and 210Pb(ex) inventories measurement in grassland environments.

    PubMed

    Li, Junjie; Li, Yong; Wang, Yanglin; Wu, Jiansheng; Funk, Roger; Hoffmann, Carsten

    2010-06-01

    In-situ measurement of fallout radionuclides (137)Cs and (210)Pb(ex) has the potential to assess soil erosion and sedimentation rapidly. In this study, inventories of (137)Cs and (210)Pb(ex) in the soil of Inner Mongolia grassland were measured using an In-situ Object Counting System (ISOCS). The results from the field study indicate that in-situ gamma-ray spectrometry has the following advantages over traditional laboratory measurements: no extra time is required for sample collection, no reference inventories are required, more economic, prompt availability of the results, the ability to average radionuclide inventory over a large area, and high precision. PMID:20133146

  17. Persistent chlordane concentrations in long island sound sediment: Implications from chlordane, 210Pb, and 137Cs profiles

    USGS Publications Warehouse

    Yang, L.; Li, X.; Crusius, J.; Jans, U.; Melcer, M.E.; Zhang, P.

    2007-01-01

    Concentrations of chlordane, a banned termiticide and pesticide, were examined in recently collected surficial sediment (10 sites) and sediment cores (4 sites) in Long Island Sound (LIS).The highest chlordane concentrations were observed in western LIS, near highly urbanized areas. Chlordane concentrations did not decrease significantly in the past decade when compared to the data collected in 1996, consistent with the observation of near-constant chlordane levels in blue mussel tissues collected during the same time period. Chlordane concentrations in many of the sites exceeded levels above which harmful effects on sediment-dwelling organisms are expected to frequently occur. Chlordane concentrations in two of the four sediment cores showed a peak below the sediment surface, suggesting reduced chlordane inputs in recent years. The lack of a chlordane concentration maximum below the sediment surface in the other two cores, coupled with the lack of a well-defined 137Cs peak, indicated significant sediment mixing. Simulations of 137Cs and 210Pb profiles in sediment cores with a simple sediment-mixing model were used to constrain both the deposition rate and the bioturbation rate of the sediment. Simulations of the chlordane profiles indicated continued chlordane input to LIS long after chlordane was phased out in the U.S. Continued chlordane input and significant sediment mixing may have contributed to the persistent chlordane concentrations in surficial sediment, which poses long-term threats to benthic organisms in LIS.

  18. Recent peat accumulation rates in minerotrophic peatlands of the Bay James region, Eastern Canada, inferred by 210Pb and 137Cs radiometric techniques.

    PubMed

    Ali, Adam A; Ghaleb, Bassam; Garneau, Michelle; Asnong, Hans; Loisel, Julie

    2008-10-01

    (210)Pb and (137)Cs dating techniques are used to characterise recent peat accumulation rates of two minerotrophic peatlands located in the La Grande Rivière hydrological watershed, in the James Bay region (Canada). Several cores were collected during the summer 2005 in different parts of the two selected peatlands. These minerotrophic patterned peatlands are presently affected by erosion processes, expressed by progressive mechanical destruction of their pools borders. This erosion process is related to a water table rise induced by a regional increase of humidity since the last century. The main objective of the present paper is to (1) evaluate if (210)Pb and (137)Cs dating techniques can be applied to build accurate chronologies in these environments and (2) detect changes in the peat accumulation rates in regard to this amplification of humidity. In both sites, unsupported (210)Pb shows an exponential decreasing according to the depth. Chronologies inferred from (210)Pb allow to reconstruct peat accumulation rates since ca. 1855 AD. The (137)Cs data displayed evident mobility and diffusion, preventing the establishment of any sustained chronology based on these measurements. In the two sites, peat accumulation rates inferred from (210)Pb chronologies fluctuate between 0.005 and 0.038 g cm(-2) yr(-1). As a result, the rise of the water table during the last decade has not yet affected peat accumulation rates.

  19. Temporal changes of 7Be, 137Cs and 210Pb activity concentrations in surface air at Monaco and their correlation with meteorological parameters.

    PubMed

    Pham, Mai K; Betti, Maria; Nies, Hartmut; Povinec, Pavel P

    2011-11-01

    Results of analysis of (7)Be, (137)Cs and (210)Pb on aerosol filters carried out from 1998 to 2010 in Monaco show that a weak correlation between activity concentrations of these radionuclides in the atmosphere and meteorological parameters has been found for (7)Be and temperature (r = 0.50), (210)Pb and temperature and humidity (r = 0.43 and 0.41, respectively), and (137)Cs and precipitation (r = 0.51). The minimum and maximum (7)Be activity concentrations were observed during 2000 and 2009, corresponding with the maximum and minimum solar activity, respectively. The maximum (137)Cs activity concentration found in May-June 1998 was due to the accident at Algeciras in Spain. The deposition velocities of (7)Be, (137)Cs and (210)Pb depended on the precipitation rate, and attained maximum values during dry seasons. The investigated radionuclides may be used as atmospheric tracers, especially in long-term periods.

  20. Comparative assessment of the contents of magnetic spherules, 137Cs, and 210Pb in soils as applied for the estimation of soil erosion

    NASA Astrophysics Data System (ADS)

    Gennadiyev, A. N.; Golosov, V. N.; Chernyanskii, S. S.; Markelov, M. V.; Kovach, R. G.; Belyaev, V. R.; Ivanova, N. N.

    2006-10-01

    The contents of magnetic spherules and 137Cs and 210Pb isotopes were determined in gray forest soils of the Novosil Agroforest Experimental Station in Orel oblast (central part of European Russia). The spatial variability in the contents of these substances was studied, and their distribution in the soil profiles and along soil transects within the afforested and cultivated slopes was analyzed. Factors and processes favoring the accumulation of magnetic spherules and 137Cs and 210Pb isotopes in the soils, as well as their removal from the soils, were revealed. Similarities and distinctions in the patterns of their behavior were interpreted. Prospects for the combined use of these three tracers to estimate the rates of soil erosion and sediment deposition on the soil surface were tested.

  1. Recent atmospheric lead deposition recorded in an ombrotrophic peat bog of Great Hinggan Mountains, Northeast China, from 210Pb and 137Cs dating.

    PubMed

    Bao, K; Xia, W; Lu, X; Wang, G

    2010-09-01

    Radioactive markers are useful in dating lead deposition patterns from industrialization in peat archive. Peat cores were collected in an ombrotrophic peat bog in the Great Hinggan Mountains in Northeast China in September 2008 and dated using (210)Pb and (137)Cs radiometric techniques. The mosses in both cores were examined systematically for dry bulk density, water and ash content. Lead also was measured using atomic emission spectroscopy with inductively coupled plasma (ICP-AES). Both patterned peat profiles were preserved well without evident anthropogenic disturbance. Unsupported (210)Pb and (137)Cs decreased with the depth in both of the two sample cores. The (210)Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the (137)Cs time marker. Recent atmospheric (210)Pb flux in Great Hinggan Mountains peat bog was estimated to be 337 Bq m(-2)y(-1), which is consistent with published data for the region. Lead deposition rate in this region was also derived from these two peat cores and ranged from 24.6 to 55.8 mg m(-2)y(-1) with a range of Pb concentration of 14-262 microg g(-1). The Pb deposition patterns were consistent with increasing industrialization over the last 135-170 y, with a peak of production and coal burning in the last 50 y in Northeast China. This work presents a first estimation of atmospheric Pb deposition rate in peatlands in China and suggests an increasing trend of environmental pollution due to anthropogenic contaminants in the atmosphere. More attention should be paid to current local pollution problems, and society should take actions to seek a balance between economic development and environmental protection.

  2. Use of 210Pb and 137Cs to simultaneously constrain ages and sources of post-dam sediments in the Cordeaux reservoir, Sydney, Australia.

    PubMed

    Simms, Ava D; Woodroffe, Colin; Jones, Brian G; Heijnis, Henk; Mann, Rob A; Harrison, Jennifer

    2008-07-01

    Environmental radionuclides can be employed as tracers of sediment movement and delivery to water bodies such as lakes and reservoirs. The chronologies of sediments that have accumulated in the Cordeaux reservoir in Sydney, Australia, were determined by the rate of change of (210)Pb(ex) with depth and indicate slow accretion in the reservoir. The ratio of enrichment of radionuclides in sediment cores to (210)Pb(ex) and (137)Cs concentrations in a reference soil sample within the Cordeaux catchment indicates that the dominant source of sediment in the Cordeaux reservoir is surface erosion (detachment and removal of sediment at depths less than 30 cm). However, in the Kembla Creek arm of the reservoir a mixture of sources was detected and includes sheet and rill erosion together with sub-soil contributions. Implications for the utility of these radionuclide sedimentation assessments, especially where samples are limited, are that well-constrained chronologies and sources of soil erosion are facilitated.

  3. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    PubMed

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes. PMID:26456908

  4. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    PubMed

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes.

  5. Distribution of 7Be, 210Pb and 137Cs in watersheds of different scales in the Seine River basin: inventories and residence times.

    PubMed

    Le Cloarec, Marie-Françoise; Bonté, Philippe; Lefèvre, Irène; Mouchel, Jean-Marie; Colbert, Steven

    2007-04-01

    The activity of environmental radionuclides ((7)Be, (210)Pb and (137)Cs) was monitored in nested catchments, inside the Seine River basin. Suspended matter data was collected at 8 different watersheds, ranging from order 1 to order 7, and ranging in size over 4 orders of magnitude. Suspended matter was analyzed for (210)Pb, (137)Cs and (7)Be, and used to calculate the flux of sediments out of each watershed. Monthly atmospheric flux data of (210)Pb and (7)Be was analyzed to assess the input flux of each into the watersheds, taking into account the rainfall during sampling periods. Taking advantage of the different half-lives of (7)Be (53 days) and (210)Pb (22 years), a two-box model was built for each of the catchments following a methodology previously developed by Dominik et al. [Dominik J, Burrus D, Vernet JP. Transport of the environmental radionuclides in alpine watershed. Earth Planet Sci Letters 1987; 84: 165-180.]. The model divides the watershed into a soil box and a rapid reservoir and provides insight into the removal rate of suspended matter from the surrounding watershed. The model enables the assessment of the surface area and the residence time of slow and rapid reservoirs to describe the fate of contaminants of atmospheric origin inside the river basin. The model was improved by considering the dissolved fraction in the total flux and adding the (137)Cs inventory as an additional constraint. The effects of these changes are discussed. Residence times in the soil box, characterized by low transport velocity, range between 4800 years at Melarchez (order 1) to about 30000 years at Andresy and Poses (order 7). They remain constant in each watershed over a large range of variation of atmospheric fluxes of (7)Be and (210)Pb during the whole study, but are sensitive to SM variations. The residence time in the rapid box, which includes the surface of the river and immediate surroundings, is less than one year, while its surface area is in the range 0.6% to

  6. Bayesian integration of radioisotope dating (210Pb, 137Cs, 241Am, 14C) and an 18-20th century mining history of Brotherswater, English Lake District

    NASA Astrophysics Data System (ADS)

    Schillereff, Daniel; Chiverrell, Richard; Macdonald, Neil; Hooke, Janet; Welsh, Katharine; Piliposyan, Gayane; Appleby, Peter

    2014-05-01

    Lake sediment records are often a useful tool for investigating landscape evolution as geomorphic changes in the catchment are reflected by altered sediment properties in the material transported through the watershed and deposited at the lake bed. Recent research at Brotherswater, an upland waterbody in the Lake District, northwest England, has focused on reconstructing historical floods from their sedimentary signatures and calculating long-term sediment and carbon budgets from fourteen sediment cores extracted from across the basin. Developing accurate chronological control is essential for these tasks. One sediment core (BW11-2; 3.5 m length) from the central basin has been dated using artificial radionuclide measurements (210Pb, 137Cs, 241Am) for the uppermost sediments and radiocarbon (14C) for lower sediments. The core appears to span the past 1500 years, however a number of problems have arisen. We present our explanations for these errors, the independent chronological techniques used to generate an accurate age-depth model for this core and methods for its transferral to the other 13 cores extracted from the basin. Two distinct 137Cs markers, corresponding to the 1986 Chernobyl disaster and 1960s weapons testing, confirm the 210Pb profile for sediment deposition since ~1950, but calculations prior to this appear erroneous, possibly due to a hiatus in the sediment record. We used high-resolution geochemical profiles (measured by XRF) to cross-correlate with a second 210Pb-dated chronology from a more distal location, which returned more sensible results. Unfortunately, the longer 14C sequence exhibits two age-reversals (radiocarbon dates that are too old). We believe the uppermost two dates are erroneous, due to a shift in inflow location as a flood prevention method ~1900 A.D., dated using information from historical maps. The lower age-reversal coincides with greater supply of terrigenous material to the lake (increased Zr, K, Ti concentrations

  7. Evaluation of the activity concentrations of (137) Cs and (40)K in some Chanterelle mushrooms from Poland and China.

    PubMed

    Falandysz, Jerzy; Zalewska, Tamara; Apanel, Anna; Drewnowska, Małgorzata; Kluza, Karolina

    2016-10-01

    The activity concentrations of (137)Cs and (40)K in mushrooms of the genus Cantharellus (Cantharellus cibarius, Cantharellus tubaeformis, and Cantharellus minor) collected across Poland from 1997 to 2013 and in Yunnan province of China in 2013 were determined using gamma spectrometry with an HPGe detector, respectively. Activity concentrations of (137)Cs in C. cibarius from the places in Poland varied from 64 ± 3 to 1600 ± 47 Bq kg(-1) db in 1997-2004 and 4.2 ± 1.2 to 1400 ± 15 Bq kg(-1) db in 2006-2013. In the Chinese Cantharellus mushrooms, the activity level of (137)Cs was very low, i.e., at a range <1.2 to 1.2 ± 0.6 Bq kg(-1) dry biomass. The natural radionuclide (40)K was at similar activity level in C. cibarius collected across Poland and in China, and fluctuations in levels of (40)K over the years and locations in Poland were small. In C. cibarius from diverse sites in Poland, content of (137)Cs highly fluctuated in 1998-2013 but no clear downward trend was visible (Fig. 1). Published activity levels of (137)Cs in fruitbodies of Cantharellus such Cantharellus californicus, Cantharellus cascadensis, C. cibarius, Cantharellus cinnabarius, Cantharellus formosus, Cantharellus iuteocomus, Cantharellus lutescens, Cantharellus minor, Cantharellus pallens [current name C. cibarius], Cantharellus subalbidus, Cantharellus subpruinosus, and C. tubaeformis collected worldwide were compared. In the Polish cuisine, mushrooms of the genus Cantharellus are blanched before frying or pickling, and this kind of treatment, and additionally also pickling, both very efficiently remove alkali elements (and radioactivity from (134/137)Cs) from flesh of the species. PMID:27438876

  8. 137Cs and 40K in the terrestrial vegetation of the Yenisey Estuary: landscape, soil and plant relationships.

    PubMed

    Korobova, Elena M; Brown, Justin B; Ukraintseva, Natalia G; Surkov, Vitaly V

    2007-01-01

    Plant species, forming important components of Arctic food chains and of interest from a monitoring perspective, were studied at 36 plots representing flood plain and terrace landscapes of the Yenisey River and Estuary from its upper delta to the gulf. (137)Cs contamination densities at the plots varied from 0.35kBq/m(2) (central delta, sandy riverside plot) to 88kBq/m(2) (the upper delta plot) indicating both global and regional sources of anthropogenic pollution. Cs-137 levels in plants were within the range expected from global fallout inputs and varied from 31 to 140Bq/kg d.w. increasing in dominant groups in the order: grasses137)Cs Tag values (0.03-0.1m(2)/kg) comparable to those found on swampy areas contaminated by Chernobyl fallout. The frontal delta island seems to act as a barrier, contributing to local accumulation of (137)Cs as reflected in higher inventories in soil and biomass. Horsetail and willow leaves were noted for higher (40)K content and lower (137)Cs Tag compared to mosses and alder, respectively. This makes the latter plant types more appropriate indicators of (137)Cs contamination.

  9. Concentrations of {sup 137}Cs and {sup 40}K in edible mushrooms collected in Japan and radiation dose due to their consumption

    SciTech Connect

    Ban-nai, Tadaaki; Muramatsu, Yasuyuki; Yoshida, Satoshi

    1997-03-01

    To estimate radiocesium intake due to eating mushrooms, about 100 samples belonging to 11 species were analyzed to establish to establish representative values for {sup 137}Cs and {sup 40}K in common edible mushrooms available in food markets. Concentration ranges were <0.047-39 Bq kg{sup -1} (wet wt) for {sup 137}Cs and 30-210 Bq kg{sup -1} (wet wt) for {sup 40}K. The median concentrations were 1.3 Bq kg{sup -1} (wet wt) for {sup 137}Cs and 97 Bq kg{sup -1} (wet wt) for {sup 40}K. The {sup 137}Cs concentration is cultivated mushrooms were markedly lower than those in wild mushrooms. The annual intake of {sup 137}Cs per person through mushrooms was calculated (using analytical results and food consumption data in Japan) to be 6.0 Bq for {sup 137}Cs, which is about 32% of the total dietary intake of this nuclide. The effective dose equivalent of {sup 137}Cs through mushroom was estimated to be 7.7 X 10{sup -8} Sv (range estimated from the standard deviation: 3.0 x 10{sup -8}-1.0 x 10{sup -7}). 19 refs., 1 fig., 2 tabs.

  10. The preliminary results of the measurements of environmental levels of 40K and 137Cs in Venezuela

    NASA Astrophysics Data System (ADS)

    LaBrecque, J. J.; Rosales, P. A.; Carias, O.

    1992-02-01

    The study of the beta-particle radioactivity in air and 90Sr in rainwater collected at Instituto Venezolano de Investigaciones Cientificas, IVIC, that began in 1959 in conjunction with the U.S. Atomic Energy Commission was discontinued in 1963. But after the Chernobyl nuclear power plant accident in the USSR, work on the radioactive contamination in Venezuela has been renewed. Initially the measurement of 134Cs and 137Cs in imported foodstuffs, such as milk powders and meats were undertaken, and these have now been extended to measurements of environmental levels of 40K and 137Cs in soils, sea sediments and foodstuffs. The data present herein are the only readily available data on radioactive contamination in the environment in Venezuela since 1963. The measurements were performed with a simple Nal(Tl) detector and two single channel analyzers as well as with a 25% efficient hyper-pure germanium semiconductor coupled to a multichannel analyzer system. Finally, these results can be used as baseline values (environmental background) in case of a nuclear accident in the region, as well as to screen imported foodstuff which is suspected to be contaminated.

  11. Distribution and possible dietary intake of radioactive 137Cs, 40K and 226Ra with the pantropical mushroom Macrocybe gigantea in SW China.

    PubMed

    Falandysz, Jerzy; Zhang, Ji; Zalewska, Tamara; Apanel, Anna; Wang, Yuanzhong; Wiejak, Anna

    2015-01-01

    There is scarcity of data on contamination with radiocesium 134/137Cs of edible mushrooms from the Southwestern Asia. This study aimed to get insight into activity concentration of artificial nuclides 134/137Cs and natural 40K and 226Ra in mushrooms from Yunnan province, which is major producer in China. The specimens of pantropical mushroom Macrocybe gigantea were collected from the wild and from a farm across Yunnan land in 2012-2013 and analyzed using gamma spectrometry with hyperpure germanium coaxial detector (HPGe). M. gigantea showed low activity concentrations of 137Cs (median value for dehydrated caps was 4.5 Bq kg(-1) and 5.4 Bq kg(-1) for stipes) while 134Cs was not detected. Natural radionuclide 40K showed 2-3 orders of magnitude greater activity concentration compared to artificial 137Cs in M. gigantea. The activity concentrations of 226Ra from uranium and radium decay series for most of the consignments of M. gigantea examined were below the method's limit of detection. The nominal effective dose equivalent for the Yunnan people from the dietary intake of 137Cs was assessed to be below 0.01 μSv per annum on the average, and that from 40K to be below 0.1 μSv per annum. Data available for the first time on activity concentrations of 137Cs in wild-grown saprobic mushroom from this region of Asia suggest low pollution with radiocesium from fallout there. Hence, the likely health risks from intake of 137Cs from cooked M. gigantea are in practice of mushrooms absent for human consumers there. Because of abundance of mushrooms in Yunnan and high significance of the region as producer and exporter a wider study using many species is necessary to fill a gap on possible radioactive contamination and risk to mushroom consumers. PMID:26061207

  12. Distribution and possible dietary intake of radioactive 137Cs, 40K and 226Ra with the pantropical mushroom Macrocybe gigantea in SW China.

    PubMed

    Falandysz, Jerzy; Zhang, Ji; Zalewska, Tamara; Apanel, Anna; Wang, Yuanzhong; Wiejak, Anna

    2015-01-01

    There is scarcity of data on contamination with radiocesium 134/137Cs of edible mushrooms from the Southwestern Asia. This study aimed to get insight into activity concentration of artificial nuclides 134/137Cs and natural 40K and 226Ra in mushrooms from Yunnan province, which is major producer in China. The specimens of pantropical mushroom Macrocybe gigantea were collected from the wild and from a farm across Yunnan land in 2012-2013 and analyzed using gamma spectrometry with hyperpure germanium coaxial detector (HPGe). M. gigantea showed low activity concentrations of 137Cs (median value for dehydrated caps was 4.5 Bq kg(-1) and 5.4 Bq kg(-1) for stipes) while 134Cs was not detected. Natural radionuclide 40K showed 2-3 orders of magnitude greater activity concentration compared to artificial 137Cs in M. gigantea. The activity concentrations of 226Ra from uranium and radium decay series for most of the consignments of M. gigantea examined were below the method's limit of detection. The nominal effective dose equivalent for the Yunnan people from the dietary intake of 137Cs was assessed to be below 0.01 μSv per annum on the average, and that from 40K to be below 0.1 μSv per annum. Data available for the first time on activity concentrations of 137Cs in wild-grown saprobic mushroom from this region of Asia suggest low pollution with radiocesium from fallout there. Hence, the likely health risks from intake of 137Cs from cooked M. gigantea are in practice of mushrooms absent for human consumers there. Because of abundance of mushrooms in Yunnan and high significance of the region as producer and exporter a wider study using many species is necessary to fill a gap on possible radioactive contamination and risk to mushroom consumers.

  13. Mobile mud dynamics in the East China Sea elucidated using 210Pb, 137Cs, 7Be, and 234Th as tracers

    NASA Astrophysics Data System (ADS)

    Wang, Jinlong; Du, Jinzhou; Baskaran, Mark; Zhang, Jing

    2016-01-01

    "Mobile mud" (MM), which has fine grain size distribution (>90% clay + silt, and <5% sand) and high porosity (≥0.50), plays an important role in the biogeochemical cycles in the estuarine areas and the inshore shelf. A suite of MM samples from the coastal area of the East China Sea (ECS) was collected in spring and summer of 2011 to observe their spatial and temporal distribution, grain size, and radionuclides concentrations. The MM thickness ranged from 0.5 to 11 cm (average: 2.2 cm (May) and 3.9 cm (August)). The thick mud layer is mainly distributed along the coast, with an area of 2.2 × 104 km2 in May and 1.5 × 104 km2 in August, with corresponding masses of 8.8 × 108 and 7.8 × 108 t, respectively. The estimated masses of MM are considerably larger than the annual sediment discharge mass of the Changjiang River. The distribution of 137Cs inventories in MM indicates that 137Cs can be effectively utilized as a transport tracer of MM in the river-dominated estuaries and coastal areas. The higher inventories of 7Be in MM in the river mouth in spring are attributed to higher depositional flux and higher sediment discharge. The ratio of the MM inventory of 234Thex/production in the overlying water column of >2.5 in south inshore indicates that the sediment focusing resulted in the increased mass flux. The residence time of MM is estimated as 3-6 years both by mass balance of MM and 210Pbex in MM.

  14. Measurement of 226Ra, 232Th, 137Cs and 40K activities of Wheat and Corn Products in Ilam Province – Iran and Resultant Annual Ingestion Radiation Dose

    PubMed Central

    CHANGIZI, Vahid; SHAFIEI, Elham; ZAREH, Mohammad Reza

    2013-01-01

    Background: Background: Natural background radiation is the main source of human exposure to radioactive material. Soils naturally have radioactive mineral contents. The aim of this study is to determine natural (238 U, 232 Th, 40 K) and artificial (137 Cs) radioactivity levels in wheat and corn fields of Eilam province. Methods: HPGe detector was used to measure the concentration activity of 238 U and 232 Th series, 40 K and 137 Cs in wheat and corn samples taken from different regions of Eilam province, in Iran. Results: In wheat and corn samples, the average activity concentrations of 226 Ra, 232 Th, 40 K and 137 Cs were found to be 1, 67, 0.5, 91.73, 0.01 and 0.81, 0.85, 101.52, 0.07 Bq/kg (dry weight), respectively. H ex and H in in the present work are lower than 1. The average value of H ex was found to be 0.02 and 0.025 and average value of H in to be found 0.025 and 0.027 in wheat fields samples and corn samples in Eilam provinces, respectively. The obtained values of AGDE are 30.49 mSv/yr for wheat filed samples and 37.89 mSv/yr for corn samples; the AEDE rate values are 5.28 mSv/yr in wheat filed samples and this average value was found to be 6.13 mSv/yr in corn samples in Eilam. Transfer factors (TFs) of long lived radionuclide such as 137 Cs, 226 Ra, 232 Th and 40 K from soils to corn and wheat plants have been studied by radiotracer experiments. Conclusion: The natural radioactivity levels in Eilam province are not at the range of high risk of morbidity and are under international standards. PMID:26056646

  15. Measurement of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs in foodstuffs samples collected from coastal areas of China.

    PubMed

    Tuo, Fei; Zhang, Qing; Zhou, Qiang; Xu, Cuihua; Zhang, Jing; Li, Wenhong; Zhang, Jianfeng; Su, Xu

    2016-05-01

    This study represents a total of 245 samples collected. The activities of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs were determined in samples of vegetables, tea, cereal (rice, wheat and corn), meat, poultry, freshwater product, seafood and seaweed that collected from the 30km safety zone of the Nuclear Power Plants (NPPs) area. All the samples radionuclide activities were quantified by using High Purity Germanium (HPGe) gamma spectrometry. The geometric mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.13, 0.16, 0.11, 68 and 0.02, respectively. The arithmetic mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.34, 0.65, 0.32, 111 and 0.09, respectively. Results of this study were compared with others, the measured values are the same with those of a previous investigation. Radiation doses due to the consumption of these foodstuffs to humans are estimated to comprise around 37-46% of the annual dose limit for public.

  16. Measurement of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs in foodstuffs samples collected from coastal areas of China.

    PubMed

    Tuo, Fei; Zhang, Qing; Zhou, Qiang; Xu, Cuihua; Zhang, Jing; Li, Wenhong; Zhang, Jianfeng; Su, Xu

    2016-05-01

    This study represents a total of 245 samples collected. The activities of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs were determined in samples of vegetables, tea, cereal (rice, wheat and corn), meat, poultry, freshwater product, seafood and seaweed that collected from the 30km safety zone of the Nuclear Power Plants (NPPs) area. All the samples radionuclide activities were quantified by using High Purity Germanium (HPGe) gamma spectrometry. The geometric mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.13, 0.16, 0.11, 68 and 0.02, respectively. The arithmetic mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.34, 0.65, 0.32, 111 and 0.09, respectively. Results of this study were compared with others, the measured values are the same with those of a previous investigation. Radiation doses due to the consumption of these foodstuffs to humans are estimated to comprise around 37-46% of the annual dose limit for public. PMID:26926376

  17. Behavior of ambient concentrations of natural radionuclides (7)Be, (210)Pb, (40)K in the Mediterranean coastal city of Málaga (Spain).

    PubMed

    Gordo, E; Dueñas, C; Fernández, M C; Liger, E; Cañete, S

    2015-05-01

    During a 4-year period (January 2009-December 2012), the (7)Be, (210)Pb, and (40)K activity concentrations in airborne particulate matter were weekly determined at the Málaga (Spain) located in the southern Iberian Peninsula. Totally 209 polypropylene filters were analyzed in the mentioned period. In 100% of the filters, (7)Be and (40)K activity concentrations were detected while (210)Pb activity concentration was detected in 96% of the filters. The results from individual measurements of (7)Be, (210)Pb, and (40)K concentrations were analyzed to derive the statistical estimates characterizing the distributions. Principal components analysis (PCA) was applied to the datasets and the results of the study reveal that aerosol behavior is represented by two principal components which explain 73.2% of total variance. Components PC1 and PC2 respectively explain 46.0 and 27.2% of total variance. PC1 was related positively to dust content, (7)Be and (40)K concentrations and negatively to sunspot numbers. In contrast, PC2 was related positively to temperature and (210)Pb activity and negatively to precipitation and relative humidity. The (7)Be levels showed a significant correlation with sunspot numbers due to the cosmogenic origin. (40)K activities showed a good correlation with dust deposition in filters mainly because it was transported to the air as resuspended particle from the soil. An inverse relationship was observed between the (210)Pb concentrations and monthly rainfall, indicating washout of atmospheric aerosols carrying these radionuclides and a pronounced positive correlation with the average monthly temperature of air.

  18. Quantification of transfer of (238)U, (226)Ra, (232)Th, (40)K and (137)Cs in mosses of a semi-natural ecosystem.

    PubMed

    Dragović, S; Mihailović, N; Gajić, B

    2010-02-01

    There is a lack of appropriate data on transfer of some radionuclides on many terrestrial biota groups. To expand the available data concentration ratios of (238)U, (226)Ra, (232)Th, (40)K and (137)Cs in mosses are presented in this paper. The relationship between concentration ratios of radionuclides and physicochemical characteristics of the underlying soil was also investigated. The data on concentration ratios obtained here will provide a useful addition to the currently used database of transfer parameters, particularly for natural radionuclides.

  19. Activity concentration measurements of 137Cs, 90Sr and 40K in a wild food matrix reference material (Wild Berries) CCRI(II)-S8

    NASA Astrophysics Data System (ADS)

    Wätjen, U.; Altzitzogloa, T.; Ceccatelli, A.; Dikmen, H.; Ferreux, L.; Frechou, C.; García, L.; Gündogdu, G.; Kis-Benedek, G.; La Rosa, J.; Luca, A.; Moreno, Y.; Oropesa, P.; Pierre, S.; Schmiedel, M.; Spasova, Y.; Szücs, L.; Vasile, M.; Wershofen, H.; Yücel, Ü.

    2014-01-01

    In 2009, the CCRI approved a supplementary comparison to be organized by the IRMM as pilot laboratory for the activity concentrations of 137Cs, 90Sr and 40K in a matrix material of dried bilberries. The organization of this comparison and the material and measurement methods used are described. The supplementary comparison reference values (SCRV) for each of the three radionuclides are given together with the degrees of equivalence of each participating laboratory with the SCRV for the specific radionuclide. The results of this supplementary comparison allow the participating NMIs/designated institutes to declare calibration and measurement capabilities (CMCs) for the given radionuclides in a similar type of food matrix, an important aspect given the relatively few supplementary comparisons for activity in matrix materials organized so far. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  20. Activity concentrations of 226Ra, 232Th, 40K and 137Cs radionuclides in Turkish medicinal herbs, their ingestion doses and cancer risks

    NASA Astrophysics Data System (ADS)

    Parmaksız, Aydın; Ağuş, Yusuf

    2014-11-01

    Twenty-two medicinal herb samples, each representing a distinct species, were collected from Turkish markets and measured by the gamma spectrometric method. The activity concentration of 226Ra in medicinal herbs was found in the range of minimum detectable activity (MDA) and 15.1 ± 2.2 Bqkg-1. The activity concentration of 232Th ranged from MDA values to 3.5 ± 0.8 Bqkg-1. The activity concentration of 40K varied between 50.0 ± 16.8 and 1311.5 ± 57.3 Bqkg-1. All 137Cs activity concentrations of medicinal herbs were found to have lower than MDA values. The bone surface dose, lower large intestine and colon doses were found to be 182.9, 18.8 and 18.7 µSvy-1, respectively. The highest committed effective dose originated from the annual ingestion of 1 kg medicinal herb was calculated notably low as 9.0 µSv. The cancer risk of ingestion of medicinal herbs was found to be small enough to be neglected. The selected Turkish medicinal herbs are considered safe for human consumption.

  1. /sup 137/Cs radioactive dating of Lake Ontario sediment cores

    SciTech Connect

    Ward, T.E.; Breeden, J.; Komisarcik, K.; Porter, R.; Czuczwa, J.; Kaminski, R.; McVeety, B.D.

    1987-12-01

    The distribution of /sup 137/Cs in sediment cores from Lake Ontario provides estimates of the sediment accumulation rates. Geochronology with /sup 210/Pb dating and distribution of Ambrosia (ragweed) pollen compare well with /sup 137/Cs dating. These methods can determine with precision, changes in sedimentation occurring over the past 100 years or so. Typical sedimentation rates of 0.18-0.36 cm/yr were measured. 16 refs., 3 figs., 2 tabs.

  2. Investigation of (235)U, (226)Ra, (232)Th, (40)K, (137)Cs, and heavy metal concentrations in Anzali international wetland using high-resolution gamma-ray spectrometry and atomic absorption spectroscopy.

    PubMed

    Zare, Mohammad Reza; Kamali, Mahdi; Fallahi Kapourchali, Maryam; Bagheri, Hashem; Khoram Bagheri, Mahdi; Abedini, Ali; Pakzad, Hamid Reza

    2016-02-01

    Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs in sediment samples ranged between 1.05 ± 0.51-5.81 ± 0.61, 18.06 ± 0.63-33.36 ± .0.34, 17.57 ± 0.38-45.84 ± 6.23, 371.88 ± 6.36-652.28 ± 11.60, and 0.43 ± 0.06-63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36-5.97, 22.71-38.37, 29.27-42.89, 472.66-533, and 1.05-9.60 Bq/kg for (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland. PMID:26490904

  3. Investigation of (235)U, (226)Ra, (232)Th, (40)K, (137)Cs, and heavy metal concentrations in Anzali international wetland using high-resolution gamma-ray spectrometry and atomic absorption spectroscopy.

    PubMed

    Zare, Mohammad Reza; Kamali, Mahdi; Fallahi Kapourchali, Maryam; Bagheri, Hashem; Khoram Bagheri, Mahdi; Abedini, Ali; Pakzad, Hamid Reza

    2016-02-01

    Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs in sediment samples ranged between 1.05 ± 0.51-5.81 ± 0.61, 18.06 ± 0.63-33.36 ± .0.34, 17.57 ± 0.38-45.84 ± 6.23, 371.88 ± 6.36-652.28 ± 11.60, and 0.43 ± 0.06-63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36-5.97, 22.71-38.37, 29.27-42.89, 472.66-533, and 1.05-9.60 Bq/kg for (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland.

  4. Ingestion dose from 238U, 232Th, 226Ra, 40K and 137Cs in cereals, pulses and drinking water to adult population in a high background radiation area, Odisha, India.

    PubMed

    Lenka, Pradyumna; Sahoo, S K; Mohapatra, S; Patra, A C; Dubey, J S; Vidyasagar, D; Tripathi, R M; Puranik, V D

    2013-03-01

    A natural high background radiation area is located in Chhatrapur, Odisha in the eastern part of India. The inhabitants of this area are exposed to external radiation levels higher than the global average background values, due to the presence of uranium, thorium and its decay products in the monazite sands bearing placer deposits in its beaches. The concentrations of (232)Th, (238)U, (226)Ra, (40)K and (137)Cs were determined in cereals (rice and wheat), pulses and drinking water consumed by the population residing around this region and the corresponding annual ingestion dose was calculated. The annual ingestion doses from cereals, pulses and drinking water varied in the range of 109.4-936.8, 10.2-307.5 and 0.5-2.8 µSv y(-1), respectively. The estimated total annual average effective dose due to the ingestion of these radionuclides in cereals, pulses and drinking water was 530 µSv y(-1). The ingestion dose from cereals was the highest mainly due to a high consumption rate. The highest contribution of dose was found to be from (226)Ra for cereals and drinking water and (40)K was the major dose contributor from the intake of pulses. The contribution of man-made radionuclide (137)Cs to the total dose was found to be minimum. (226)Ra was found to be the largest contributor to ingestion dose from all sources.

  5. PLANTS AS BIO-MONITORS FOR 137CS, 238PU, 239, 240PU AND 40K AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Caldwell, E.; Duff, M.; Ferguson, C.

    2010-12-16

    The nuclear fuel cycle generates a considerable amount of radioactive waste, which often includes nuclear fission products, such as strontium-90 ({sup 90}Sr) and cesium-137 ({sup 137}Cs), and actinides such as uranium (U) and plutonium (Pu). When released into the environment, large quantities of these radionuclides can present considerable problems to man and biota due to their radioactive nature and, in some cases as with the actinides, their chemical toxicity. Radionuclides are expected to decay at a known rate. Yet, research has shown the rate of elimination from an ecosystem to differ from the decay rate due to physical, chemical and biological processes that remove the contaminant or reduce its biological availability. Knowledge regarding the rate by which a contaminant is eliminated from an ecosystem (ecological half-life) is important for evaluating the duration and potential severity of risk. To better understand a contaminants impact on an environment, consideration should be given to plants. As primary producers, they represent an important mode of contamination transfer from sediments and soils into the food chain. Contaminants that are chemically and/or physically sequestered in a media are less likely to be bio-available to plants and therefore an ecosystem.

  6. Dating of sediments from four Swiss prealpine lakes with (210)Pb determined by gamma-spectrometry: progress and problems.

    PubMed

    Putyrskaya, V; Klemt, E; Röllin, S; Astner, M; Sahli, H

    2015-07-01

    In this paper the most important problems in dating lake sediments with unsupported (210)Pb are summarized and the progress in gamma-spectrometry of the unsupported (210)Pb is discussed. The main topics of these studies concern sediment samples preparation for gamma-spectrometry, measurement techniques and data analysis, as well as understanding of accumulation and sedimentation processes in lakes. The vertical distributions of artificial ((137)Cs, (241)Am, (239)Pu) and natural radionuclides ((40)K, (210,214)Pb, (214)Bi) as well as stable trace elements (Fe, Mn, Pb) in sediment cores from four Swiss lakes were used as examples for the interpretation, inter-comparison and validation of depth-age relations established by three (210)Pb-based models (CF-CSR, CRS and SIT). The identification of turbidite layers and the influence of the turbidity flows on the accuracy of sediment dating is demonstrated. Time-dependent mass sedimentation rates in lakes Brienz, Thun, Biel and Lucerne are discussed and compared with published data.

  7. Accumulation of 210Pb, 226Ra and radioactive cesium by fungi.

    PubMed

    Kirchner, G; Daillant, O

    1998-10-15

    Fungi sampled in three areas in France were analyzed by gamma-spectrometry for their concentrations of 134Cs, 137Cs, 210Pb and 226Ra. In most of the samples radioactive cesium was detected with a maximum of 2860 Bq kg-1 (dry wt.). Activity concentrations of 210Pb were in the range < 1.76-36.5 Bq kg-1 (dry wt.). Activity concentrations of 226Ra were consistently lower, often by one order of magnitude. Models are developed to estimate the contributions of atmospheric 210Pb deposited onto the fruit bodies to the measured 210Pb concentrations and of the uptake of 222Rn soluted in soil pore water which subsequently decays into 210Pb. It is shown that both pathways are of only minor importance. Comparison with the soil-mushroom concentration ratios of stable lead, which were determined for some of the samples, confirmed that 210Pb in mushrooms mainly originates from direct uptake of 210Pb present in the soil. Despite of the high concentrations of 137Cs detected in most of the mushrooms, radiation doses to individuals due to mushroom consumption are dominated by 210Pb for the majority of the edible mushrooms sampled.

  8. Plutonium as a chronomarker in Australian and New Zealand sediments: a comparison with (137)Cs.

    PubMed

    Hancock, G J; Leslie, C; Everett, S E; Tims, S G; Brunskill, G J; Haese, R

    2011-10-01

    The construction of high resolution chronologies of sediment profiles corresponding to the last 50-100 years usually entails the measurement of fallout radionuclides (210)Pb and (137)Cs. The anthropogenic radionuclide, (137)Cs, originating from atmospheric nuclear weapons testing can provide an important "first appearance" horizon of known age (1954-1955), providing much-needed validation for the sometimes uncertain interpretations associated with (210)Pb geochronology. However, while (137)Cs usually provides a strong signal in sediment in the northern hemisphere, total fallout of (137)Cs in the southern hemisphere was only 25% that of the north and the low activities of (137)Cs seen in Australian and New Zealand sediments can make its horizon of first appearance somewhat arguable. Low (137)Cs fallout also limited the size of the 1963-1964 fallout peak, a peak that is usually seen in northern hemisphere sediment profiles but is often difficult to discern south of the equator. This paper shows examples of the use of nuclear weapons fallout Pu as a chronomarker in sediment cores from Australia (3 sites) and New Zealand (1 site). The Pu profiles of five cores are examined and compared with the corresponding (137)Cs profiles and (210)Pb geochronologies. We find that Pu has significant advantages over (137)Cs, including greater measurement sensitivity using alpha spectrometry and mass spectrometric techniques compared to (137)Cs measurements by gamma spectrometry. Moreover, Pu provides additional chronomarkers associated with changes in the Pu isotopic composition of fallout during the 1950s and 1960s. In particular, the (238)Pu/(239+240)Pu activity ratio shows distinct shifts in the early 1950s and the mid to late 1960s, providing important known-age horizons in southern hemisphere sediments. For estuarine and near-shore sediments Pu sometimes has another significant advantage over (137)Cs due to its enrichment in bottom sediment relative to (137)Cs resulting from the

  9. 210Pb dating

    USGS Publications Warehouse

    Swarzenski, Peter W.

    2014-01-01

    Roughly fifty years ago, a small group of scientists from Belgium and the United States, trying to better constrain ice sheet accumulation rates, attempted to apply what was then know about environmental lead as a potential geochronometer. Thus Goldberg (1963) developed the first principles of the 210Pb dating method, which was soon followed by a paper by Crozaz et al. (1964), who examined accumulation history of Antarctic snow using 210Pb. Shortly thereafter, Koide et al. (1972, 1973) adapted this technique to unravel sediment deposition and accumulation records in deep-sea environments. Serendipitously, they chose to work in a deep basin off California, where an independent and robust age model had already been developed. Krishanswami et al. (1971) extended the use of this technique to lacustrine deposits to reconstruct depositional histories of lake sediment, and maybe more importantly, contaminant inputs and burial. Thus, the powerful tool for dating recent (up to about one century old) sediment deposits was established and soon widely adopted. Today almost all oceanographic or limnologic studies that address recent depositional reconstructions employ 210Pb as one of several possible geochronometers (Andrews et al., 2009; Gale, 2009; Baskaran, 2011; Persson and Helms, 2011). This paper presents a short overview of the principles of 210Pb dating and provides a few examples that illustrate the utility of this tracer in contrasting depositional systems. Potential caveats and uncertainties (Appleby et al., 1986; Binford, 1990; Binford et al., 1993; Smith, 2001; Hancock et al., 2002) inherent to the use and interpretation of 210Pb-derived age-models are also introduced. Recommendations as to best practices for most reliable uses and reporting are presented in the summary.

  10. Accumulation and distribution of 137Cs in tropical plants

    NASA Astrophysics Data System (ADS)

    Anjos, R. M.; Carvalho, C.; Mosquera, B.; Veiga, R.; Sanches, N.; Bastos, J.; Macario, K.

    2007-02-01

    The accumulation and distribution of 40K and 137Cs in several tropical plant species were studied through measurements of gamma-ray spectra, focusing on establishing the suitability of using radiocesium to trace the plant uptake of nutrients such as potassium.

  11. Accumulation and distribution of 137Cs in tropical plants

    SciTech Connect

    Anjos, R. M.; Carvalho, C.; Mosquera, B.; Veiga, R.; Sanches, N.; Bastos, J.; Macario, K.

    2007-02-12

    The accumulation and distribution of 40K and 137Cs in several tropical plant species were studied through measurements of gamma-ray spectra, focusing on establishing the suitability of using radiocesium to trace the plant uptake of nutrients such as potassium.

  12. 210Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina.

    PubMed

    Di Gregorio, D E; Fernández Niello, J O; Huck, H; Somacal, H; Curutchet, G

    2007-01-01

    Concentrations of (210)Pb and (137)Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The (210)Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The (137)Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere.

  13. Vertical profile of 137Cs in soil.

    PubMed

    Krstić, D; Nikezić, D; Stevanović, N; Jelić, M

    2004-12-01

    In this paper, a vertical distribution of 137Cs in undisturbed soil was investigated experimentally and theoretically. Soil samples were taken from the surroundings of the city of Kragujevac in central Serbia during spring-summer of 2001. The sampling locations were chosen in such a way that the influence of soil characteristics on depth distribution of 137Cs in soil could be investigated. Activity of 137Cs in soil samples was measured using a HpGe detector and multi-channel analyzer. Based on vertical distribution of 137Cs in soil which was measured for each of 10 locations, the diffusion coefficient of 137Cs in soil was determined. In the next half-century, 137Cs will remain as the source of the exposure. Fifteen years after the Chernobyl accident, and more than 30 years after nuclear probes, the largest activity of 137Cs is still within 10 cm of the upper layer of the soil. This result confirms that the penetration of 137Cs in soil is a very slow process. Experimental results were compared with two different Green functions and no major differences were found between them. While both functions fit experimental data well in the upper layer of soil, the fitting is not so good in deeper layers. Although the curves obtained by these two functions are very close to each other, there are some differences in the values of parameters acquired by them. PMID:15388151

  14. [Rapid determination of 137Cs in environmental samples--purification of 137Cs by ammonium molybdophosphate column separation].

    PubMed

    Nonaka, N; Sato, K; Higuchi, H; Hamaguchi, H

    1976-10-01

    A rapid method for the determination of 137Cs in environmental samples was proposed. The principal technic employed in this study is based on column separation of 137Cs using ammonium molybdophosphate mixed with glass fiber to eliminate contribution of natural radionuclides such as 40K and 87Rb. The separation of cesium from potassium and rubidium was performed by the elution with 0.5m ammonium nitrate solution. The time required for separation of cesium was five hours as compared with the conventional cation exchange separation which required thirteen hours. The chemical yield of cesium carrier was normally more than 90 percent. The results obtained were compared with that by the conventional methods using Bio-Rex cation exchange separation and the good agreement between the two methods was obtained. PMID:1037401

  15. Dating sediment in a fast sedimentation reservoir using 137Cs and 210Pb

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 10,000 reservoirs have been constructed in agricultural watersheds in the United States since the 1940s to control floods and sediments. Reservoir sedimentation records provide a unique opportunity to retrospectively study the effects of land use changes and climate variations on sediment produ...

  16. VULNERABILITY OF HEADWATER CATCHMENT RESOURCES TO INCIDENCES OF 210PB EXCESS AND 137CS RADIONUCLIDE FALLOUT

    EPA Science Inventory

    Recent identification of elevated excess 210Pb (≤302.6 mBq L-1) and 137Cs (≤ 111.3 mBq L-1) activity in drinking water wells up to 20 m depth indicates some transport of airborne radionuclide fallout beyond soils in the Shaker Village c...

  17. Measurement of natural and 137Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    NASA Astrophysics Data System (ADS)

    Öksüz, I.; Güray, R. T.; Özkan, N.; Yalçin, C.; Ergül, H. A.; Aksan, S.

    2016-03-01

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring 238U, 232Th and 40K isotopes and also that of an artificial isotope 137Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of 238U and 232Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the 40K are higher than the average worldwide value. A small amount of 137Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  18. A biokinetic model for {sup 137}Cs

    SciTech Connect

    Melo, D.R.; Lipsztein, J.L.; Oliveira, C.A.N.; Lundgren, D.L.

    1997-08-01

    An improved biokinetic model for {sup 137}Cs in humans was developed based on an analysis of data obtained from individuals internally contaminated during an accident in Goiania, Brazil, and other data. Seventeen children (ten girls and seven boys 1-10 y old), ten adolescents (four females and six males), and thirty adults, (fifteen females and fifteen males) contaminated in the accident in Goiania contributed to this study. {sup 137}Cs retention was determined through periodic measurements in a whole-body counter. In addition to the data on {sup 137}Cs retention from these individuals, data from a study on the metabolism of {sup 137}Cs in immature, adult, and aged Beagle dogs and data from the literature were used in the formulation of the {sup 137}Cs biokinetic model presented. Mathematically, the retention of cesium is described by three exponential terms, and the retention model is based on a step function of body weight. When the ICRP Publication 56 model for cesium was compared to the model suggested in this paper, it was determined that the ICRP model predicts lower effective doses in 5-y-old children and higher effective doses in infants, adolescents, and adults.

  19. Modeling the downward transport of (210)Pb in Peatlands: Initial Penetration-Constant Rate of Supply (IP-CRS) model.

    PubMed

    Olid, Carolina; Diego, David; Garcia-Orellana, Jordi; Cortizas, Antonio Martínez; Klaminder, Jonatan

    2016-01-15

    The vertical distribution of (210)Pb is commonly used to date peat deposits accumulated over the last 100-150 years. However, several studies have questioned this method because of an apparent post-depositional mobility of (210)Pb within some peat profiles. In this study, we introduce the Initial Penetration–Constant Rate of Supply (IP-CRS) model for calculating ages derived from 210Pb profiles that are altered by an initial migration of the radionuclide. This new, two-phased, model describes the distribution of atmospheric-derived (210)Pb ((210)Pbxs) in peat taking into account both incorporation of (210)Pb into the accumulating peat matrix as well as an initial flushing of (210)Pb through the uppermost peat layers. The validity of the IP-CRS model is tested in four anomalous (210)Pb peat records that showed some deviations from the typical exponential decay profile not explained by variations in peat accumulation rates. Unlike the most commonly used (210)Pb-dating model (Constant Rate of Supply (CRS)), the IP-CRS model estimates peat accumulation rates consistent with typical growth rates for peatlands from the same areas. Confidence in the IP-CRS chronology is also provided by the good agreement with independent chronological markers (i.e. (241)Am and (137)Cs). Our results showed that the IP-CRS can provide chronologies from peat records where (210)Pb mobility is evident, being a valuable tool for studies reconstructing past environmental changes using peat archives during the Anthropocene. PMID:26476062

  20. Reactive barriers for 137Cs retention.

    PubMed

    Krumhansl, J L; Brady, P V; Anderson, H L

    2001-02-01

    137Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137Cs from soils and groundwaters is exceedingly difficult. Because the half-life of 137Cs is only 30.2 years, remediation might be more effective (and less costly) if 137Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135Cs (half-life 2.3 x 10(6) years) in addition to 137Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-Ill were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (approximately 0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers. PMID:11288579

  1. Reactive barriers for 137Cs retention.

    PubMed

    Krumhansl, J L; Brady, P V; Anderson, H L

    2001-02-01

    137Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137Cs from soils and groundwaters is exceedingly difficult. Because the half-life of 137Cs is only 30.2 years, remediation might be more effective (and less costly) if 137Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135Cs (half-life 2.3 x 10(6) years) in addition to 137Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-Ill were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (approximately 0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers.

  2. Bioconcentration of fallout sup 137 Cs by fungi and red-backed voles (Clethrionomys gapperi)

    SciTech Connect

    Mihok, S.; Schwartz, B.; Wiewel, A.M. )

    1989-12-01

    Cesium-137 and 40K concentrations were measured in vegetation and in red-backed voles (Clethrionomys gapperi) in southeastern Manitoba, Canada, following the Chernobyl accident in 1986. Voles from wet coniferous habitats contained concentrations of {sup 137}Cs twenty- to fiftyfold higher than voles from deciduous habitats. Maximum {sup 137}Cs values were observed in autumn. Voles captured in a spruce bog at this time contained an average body burden of about 11 Bq. Concentrations in vegetation samples were similar to those found by other researchers. Overall, there was only minimal evidence of contamination attributable to Chernobyl in either vegetation or voles. The primary source of {sup 137}Cs in voles appeared to be dietary, particularly mushrooms that contained up to 74 Bq g-1 ash. Based on physiological constraints, mushrooms were the only plausible source of {sup 137}Cs in autumn diets. Elevated values at other times in coniferous areas may have been related to the consumption of epiphytic lichens. These findings suggest that fungi, or the animals that consume them, can serve as sensitive indicators of {sup 137}Cs contamination in the environment.

  3. Reactive barriers for {sup 137}Cs retention

    SciTech Connect

    KRUMHANSL,JAMES L.; BRADY,PATRICK V.; ANDERSON,HOWARD L.

    2000-05-19

    {sup 137}Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of {sup 137}Cs from soils and groundwaters is exceedingly difficult. Because the half life of {sup 137}Cs is only 30.2 years, remediation might be more effective (and less costly) if {sup 137}Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with {sup 135}Cs (half life 2.3x10{sup 6} years) in addition to {sup 137}Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention Cs resorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO{sub 3} and LiCl washes. Washed clay were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F- 111 were similar; 0.017 to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12 to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake so most soils have some limited ability to act as a natural barrier to Cs migration. However, the residual loading was greatest on K-Mbt ({approximately} 0.33 wt% Cs). Thus, this clay would be the optimal material for constructing artificial reactive barriers.

  4. Validating the use of 137Cs and 210Pbex measurements to estimate rates of soil loss from cultivated land in southern Italy.

    PubMed

    Porto, Paolo; Walling, Des E

    2012-04-01

    Soil erosion represents an important threat to the long-term sustainability of agriculture and forestry in many areas of the world, including southern Italy. Numerous models and prediction procedures have been developed to estimate rates of soil loss and soil redistribution, based on the local topography, hydrometeorology, soil type and land management. However, there remains an important need for empirical measurements to provide a basis for validating and calibrating such models and prediction procedures as well as to support specific investigations and experiments. In this context, erosion plots provide useful information on gross rates of soil loss, but are unable to document the efficiency of the onward transfer of the eroded sediment within a field and towards the stream system, and thus net rates of soil loss from larger areas. The use of environmental radionuclides, particularly caesium-137 ((137)Cs) and excess lead-210 ((210)Pb(ex)), as a means of estimating rates of soil erosion and deposition has attracted increasing attention in recent years and the approach has now been recognised as possessing several important advantages. In order to provide further confirmation of the validity of the estimates of longer-term erosion and soil redistribution rates provided by (137)Cs and (210)Pb(ex) measurements, there is a need for studies aimed explicitly at validating the results obtained. In this context, the authors directed attention to the potential offered by a set of small erosion plots located near Reggio Calabria in southern Italy, for validating estimates of soil loss provided by (137)Cs and (210)Pb(ex) measurements. A preliminary assessment suggested that, notwithstanding the limitations and constraints involved, a worthwhile investigation aimed at validating the use of (137)Cs and (210)Pb(ex) measurements to estimate rates of soil loss from cultivated land could be undertaken. The results demonstrate a close consistency between the measured rates of soil

  5. (210)Pb as a tracer of soil erosion, sediment source area identification and particle transport in the terrestrial environment.

    PubMed

    Matisoff, Gerald

    2014-12-01

    Although (137)Cs has been used extensively to study soil erosion and particle transport in the terrestrial environment, there has been much less work using excess or unsupported (210)Pb ((210)Pbxs) to study the same processes. Furthermore, since (137)Cs activities in soils are decreasing because of radioactive decay, some locations have an added complication due to the addition of Chernobyl-derived (137)Cs, and the activities of (137)Cs in the southern hemisphere are low, there is a need to develop techniques that use (210)Pbxs to provide estimates of rates of soil erosion and particle transport. This paper reviews the current status of (210)Pbxs methods to quantify soil erosion rates, to identify and partition suspended sediment source areas, and to determine the transport rates of particles in the terrestrial landscape. Soil erosion rates determined using (210)Pbxs are based on the unsupported (210)Pb ((210)Pbxs) inventory in the soil, the depth distribution of (210)Pbxs, and a mass balance calibration ('conversion model') that relates the soil inventory to the erosion rate using a 'reference site' at which neither soil erosion nor soil deposition has occurred. In this paper several different models are presented to illustrate the effects of different model assumptions such as the timing, depth and rates of the surface soil mixing on the calculated erosion rates. The suitability of model assumptions, including estimates of the depositional flux of (210)Pbxs to the soil surface and the post-depositional mobility of (210)Pb are also discussed. (210)Pb can be used as one tracer to permit sediment source area identification. This sediment 'fingerprinting' has been extended far beyond using (210)Pb as a single radioisotope to include numerous radioactive and stable tracers and has been applied to identifying the source areas of suspended sediment based on underlying rock type, land use (roads, stream banks, channel beds, cultivated or uncultivated lands, pasture lands

  6. Natural radionuclides and (137)Cs distributions and their relationship with sedimentological processes in Patras Harbour, Greece.

    PubMed

    Papaefthymiou, H; Papatheodorou, G; Moustakli, A; Christodoulou, D; Geraga, M

    2007-01-01

    Surficial and subsurficial sediment samples derived from gravity cores, selected from the harbour of Patras, Greece, were analyzed for grain size, water content, bulk density, specific gravity, organic carbon content and specific activities of natural radionuclides and (137)Cs. The specific activities of (232)Th, (226)Ra, (40)K and (137)Cs were measured radiometrically. The radionuclides (238)U and (232)Th were also analyzed using the INAA. The differences found between the specific activities of the natural radionuclides measured by the two methods are of no statistical significance. The sediment cores selection was based on a detailed bathymetric and marine seismic survey. Through the study of the detailed bathymetric map and the seismic profiles it was shown that ship traffic is highly influential to the harbour bathymetry. The granulometric and geotechnical properties of the sediments and therefore the specific activities of the natural radionuclides and (137)Cs seem to be controlled by the ship traffic. Relationship between radionuclide activity concentrations and granulometric/geotechnical parameters was defined after the treatment of all the analyses using R-mode factor analysis. The natural radionuclide activities are related to the fine fraction and bulk density of the sediments, while (137)Cs is mainly influenced by the organic carbon content. In addition, (238)U and (226)Ra seem to be in close relation with the heavy minerals fraction in coarse-grained sediments with high specific gravity.

  7. Assessment of soil erosion and deposition rates in a Moroccan agricultural field using fallout 137Cs and 210Pbex.

    PubMed

    Benmansour, M; Mabit, L; Nouira, A; Moussadek, R; Bouksirate, H; Duchemin, M; Benkdad, A

    2013-01-01

    In Morocco land degradation - mainly caused by soil erosion - is one of the most serious agroenvironmental threats encountered. However, only limited data are available on the actual magnitude of soil erosion. The study site investigated was an agricultural field located in Marchouch (6°42' W, 33° 47' N) at 68 km south east from Rabat. This work demonstrates the potential of the combined use of (137)Cs, (210)Pb(ex) as radioisotopic soil tracers to estimate mid and long term erosion and deposition rates under Mediterranean agricultural areas. The net soil erosion rates obtained were comparable, 14.3 t ha(-1) yr(-1) and 12.1 ha(-1) yr(-1) for (137)Cs and (210)Pb(ex) respectively, resulting in a similar sediment delivery ratio of about 92%. Soil redistribution patterns of the study field were established using a simple spatialisation approach. The resulting maps generated by the use of both radionuclides were similar, indicating that the soil erosion processes has not changed significantly over the last 100 years. Over the previous 10 year period, the additional results provided by the test of the prediction model RUSLE 2 provided results of the same order of magnitude. Based on the (137)Cs dataset established, the contribution of the tillage erosion impact has been evaluated with the Mass Balance Model 3 and compared to the result obtained with the Mass Balance Model 2. The findings highlighted that water erosion is the leading process in this Moroccan cultivated field, tillage erosion under the experimental condition being the main translocation process within the site without a significant and major impact on the net erosion.

  8. Sediment chronology in San Francisco Bay, California, defined by 210Pb, 234Th, 137Cs, and 239,340Pu

    USGS Publications Warehouse

    Fuller, C.C.; van Geen, Alexander; Baskaran, M.; Anima, R.

    1999-01-01

    Sediment chronologies based on radioisotope depth profiles were developed at two sites in the San Francisco Bay estuary to provide a framework for interpreting historical trends in organic compound and metal contaminant inputs. At Richardson Bay near the estuary mouth, sediments are highly mixed by biological and/or physical processes. Excess  penetration ranged from 2 to more than 10 cm at eight coring sites, yielding surface sediment mixing coefficients ranging from 12 to 170 cm2/year. At the site chosen for contaminant analyses, excess  activity was essentially constant over the upper 25 cm of the core with an exponential decrease below to the supported activity between 70 and 90 cm. Both  and  penetrated to 57-cm depth and have broad subsurface maxima between 33 and 41 cm. The best fit of the excess  profile to a steady state sediment accumulation and mixing model yielded an accumulation rate of 0.825 g/cm2/year (0.89 cm/year at sediment surface), surface mixing coefficient of 71 cm2/year, and 33-cm mixed zone with a half-Gaussian depth dependence parameter of 9 cm. Simulations of  and  profiles using these parameters successfully predicted the maximum depth of penetration and the depth of maximum  and  activity. Profiles of successive 1-year hypothetical contaminant pulses were generated using this parameter set to determine the age distribution of sediments at any depth horizon. Because of mixing, sediment particles with a wide range of deposition dates occur at each depth. A sediment chronology was derived from this age distribution to assign the minimum age of deposition and a date of maximum deposition to a depth horizon. The minimum age of sediments in a given horizon is used to estimate the date of first appearance of a contaminant from its maximum depth of penetration. The date of maximum deposition is used to estimate the peak year of input for a contaminant from the depth interval with the highest concentration of that contaminant. Because of the extensive mixing, sediment-bound constituents are rapidly diluted with older material after deposition. In addition, contaminants persist in the mixed zone for many years after deposition. More than 75 years are required to bury 90% of a deposited contaminant below the mixed zone. Reconstructing contaminant inputs is limited to changes occurring on a 20-year time scale. In contrast, mixing is much lower relative to accumulation at a site in San Pablo Bay. Instead, periods of rapid deposition and/or erosion occurred as indicated by frequent sand-silt laminae in the X-radiograph. , , and excess  activity all penetrated to about 120 cm. The distinct maxima in the fallout radionuclides at 105–110 cm yielded overall linear sedimentation rates of 3.9 to 4.1 cm/year, which are comparable to a rate of 4.5±1.5 cm/year derived from the excess  profile.

  9. Radiolead (210)Pb and (210)Po/(210)Pb activity ratios in dogs' hair.

    PubMed

    Strumińska-Parulska, Dagmara I; Szymańska, Karolina; Skwarzec, Bogdan

    2015-01-01

    The aim of this study was to determine activity concentrations of radiolead (210)Pb as well as (210)Po/(210)Pb activity ratios in dog hair. The objectives of this research were also to investigate the utility of domestic animal hair as a noninvasive indicator of metal exposure for radiotoxic, naturally occurring (210)Pb and find the correlations between (210)Pb concentration in hair and age, gender, hair type or diet of analyzed animals. The highest (210)Pb concentrations were measured in a 2-year-old Shih Tzus (9.82 ± 0.53 Bq kg(-1) dw(-1)) and a 2-year-old Bichon Maltese (8.09 ± 0.42 Bq kg(-1) dw(-1)), both longhair males, while the lowest was found in a 15-year-old Yorkshire Terrier (0.44 ± 0.02 Bq kg(-1) dw(-1)), small longhair male as well. As results showed, mainly dog hair color as well as their age and gender influenced the differences in the values of (210)Pb concentrations in analyzed hair samples. Also the values of activity ratios of (210)Po/(210)Pb in analyzed dog hair samples were calculated and obtained results were similar to those observed in human hair. PMID:26191992

  10. Radiolead (210)Pb and (210)Po/(210)Pb activity ratios in dogs' hair.

    PubMed

    Strumińska-Parulska, Dagmara I; Szymańska, Karolina; Skwarzec, Bogdan

    2015-01-01

    The aim of this study was to determine activity concentrations of radiolead (210)Pb as well as (210)Po/(210)Pb activity ratios in dog hair. The objectives of this research were also to investigate the utility of domestic animal hair as a noninvasive indicator of metal exposure for radiotoxic, naturally occurring (210)Pb and find the correlations between (210)Pb concentration in hair and age, gender, hair type or diet of analyzed animals. The highest (210)Pb concentrations were measured in a 2-year-old Shih Tzus (9.82 ± 0.53 Bq kg(-1) dw(-1)) and a 2-year-old Bichon Maltese (8.09 ± 0.42 Bq kg(-1) dw(-1)), both longhair males, while the lowest was found in a 15-year-old Yorkshire Terrier (0.44 ± 0.02 Bq kg(-1) dw(-1)), small longhair male as well. As results showed, mainly dog hair color as well as their age and gender influenced the differences in the values of (210)Pb concentrations in analyzed hair samples. Also the values of activity ratios of (210)Po/(210)Pb in analyzed dog hair samples were calculated and obtained results were similar to those observed in human hair.

  11. 137Cs in the western South Pacific Ocean.

    PubMed

    Yamada, Masatoshi; Wang, Zhong-Liang

    2007-09-01

    The 137Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea (two stations) Basins of the western South Pacific Ocean by gamma spectrometry using a low background Ge detector. The 137Cs activities ranged from 1.4 to 2.3 Bq m(-3) over the depth interval 0-250 m and decreased exponentially from the subsurface to 1000 m depth. The distribution profiles of 137Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. There was a remarkable difference for the vertical profiles of 137Cs activity between the East Caroline Basin station in this study and the GEOSECS (Geochemical Ocean Sections Study) station at the same latitude in the Equatorial Pacific Ocean; the 137Cs inventory over the depth interval 100-1000 m increased from 400+/-30 Bq m(-2) to 560+/-30 Bq m(-2) during the period from 1973 to 1992. The total 137Cs inventories in the western South Pacific Ocean ranged from 850+/-70 Bq m(-2) in the Coral Sea Basin to 1270+/-90 Bq m(-2) in the South Fiji Basin. Higher 137Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137Cs inventories were 1.9-4.5 times (2.9+/-0.7 on average) and 1.7-4.3 times (3.1+/-0.7 on average) higher than that of the expected deposition density of atmospheric global fallout at the same latitude and that of the estimated 137Cs deposition density in 10 degrees latitude by 10 degrees longitude grid data obtained by Aoyama et al. [Aoyama M, Hirose K, Igarashi Y. Re-construction and updating our understanding on the global weapons tests 137Cs fallout. J Environ Monit 2006;8:431-438], respectively. The possible processes for higher 137Cs inventories in the western South Pacific Ocean than that of the expected deposition density of atmospheric global fallout may be attributable to the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137Cs from

  12. 137Cs in the western South Pacific Ocean.

    PubMed

    Yamada, Masatoshi; Wang, Zhong-Liang

    2007-09-01

    The 137Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea (two stations) Basins of the western South Pacific Ocean by gamma spectrometry using a low background Ge detector. The 137Cs activities ranged from 1.4 to 2.3 Bq m(-3) over the depth interval 0-250 m and decreased exponentially from the subsurface to 1000 m depth. The distribution profiles of 137Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. There was a remarkable difference for the vertical profiles of 137Cs activity between the East Caroline Basin station in this study and the GEOSECS (Geochemical Ocean Sections Study) station at the same latitude in the Equatorial Pacific Ocean; the 137Cs inventory over the depth interval 100-1000 m increased from 400+/-30 Bq m(-2) to 560+/-30 Bq m(-2) during the period from 1973 to 1992. The total 137Cs inventories in the western South Pacific Ocean ranged from 850+/-70 Bq m(-2) in the Coral Sea Basin to 1270+/-90 Bq m(-2) in the South Fiji Basin. Higher 137Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137Cs inventories were 1.9-4.5 times (2.9+/-0.7 on average) and 1.7-4.3 times (3.1+/-0.7 on average) higher than that of the expected deposition density of atmospheric global fallout at the same latitude and that of the estimated 137Cs deposition density in 10 degrees latitude by 10 degrees longitude grid data obtained by Aoyama et al. [Aoyama M, Hirose K, Igarashi Y. Re-construction and updating our understanding on the global weapons tests 137Cs fallout. J Environ Monit 2006;8:431-438], respectively. The possible processes for higher 137Cs inventories in the western South Pacific Ocean than that of the expected deposition density of atmospheric global fallout may be attributable to the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137Cs from

  13. The transfer of {sup 137}Cs from barley to beer

    SciTech Connect

    Proehl, G.; Mueller, H.; Voigt, G.

    1997-01-01

    Beer has been brewed from barley contaminated with {sup 137}Cs as a consequence of the Chernobyl accident. The {sup 137}Cs activity has been measured in all intermediate steps and in the by-products of the production process. About 35 % of the {sup 137}Cs in barley were recovered in beer. Processing factors defined as the concentration ratio of processed and raw products were determined to be 0.61, 3.3, 0.1 and 0.11 for malt, malt germs, spent grains and beer, respectively. 4 refs., 2 tabs.

  14. The presence of natural radioactivity and 137Cs in the South China Sea bordering peninsular Malaysia.

    PubMed

    Amin, Y M; Mahat, R H; Nor, R M; Khandaker, Mayeen Uddin; Takleef, Ghazwa Hatem; Bradley, D A

    2013-10-01

    The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment. PMID:23584496

  15. The presence of natural radioactivity and 137Cs in the South China Sea bordering peninsular Malaysia.

    PubMed

    Amin, Y M; Mahat, R H; Nor, R M; Khandaker, Mayeen Uddin; Takleef, Ghazwa Hatem; Bradley, D A

    2013-10-01

    The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment.

  16. 210Pb mass accumulation rates in the depositional area of the Magra River (Mediterranean Sea, Italy)

    NASA Astrophysics Data System (ADS)

    Delbono, I.; Barsanti, M.; Schirone, A.; Conte, F.; Delfanti, R.

    2016-08-01

    Nine sediment cores were collected between 2009 and 2012 in the inner continental shelf (Mediterranean Sea, Italy) mainly influenced by the Magra River, at water depths ranging from 11 to 64 m. Mass Accumulation Rates (MARs) were calculated through 210Pb analysed by Gamma spectrometry. Three different dating models (single and two-layer CF-CS, CRS) were applied to clay normalised 210Pbxs profiles and 137Cs was used to validate the 210Pb geochronology. The maximum MAR values (>2 g cm-2 yr-1) were found in the region adjacent to the Magra River mouth and outside the Gulf of La Spezia (0.9±0.1 g cm-2 yr-1 at St. 3-C6 and 4-C4). Results from 137Cs/210Pbxs ratios calculated in Surface Mixed Layers (SMLs) evidenced the coastal boundaries of the Magra River depositional area, which is very limited towards south. Differently, in the north-west sector, fine sediments are generally driven by the Ligurian Current and move towards north-west: at the deepest and most distant station from the River mouth, the MAR value is the lowest one in the study area. Few major Magra River floods occurred during the sediment core sampling period. By using the short-lived radioisotope 7Be as a tracer of river floods, a clear 7Be signature of 2009 flood is present at St. 1-SA1C. Finally, by analyzing the clay normalised 210Pbxs profiles, a decrease of its activity dating the years 1999 and 2000 is observed in four cores, corresponding to two major Magra River floods occurring in those years.

  17. Accumulation of 137Cs in puddle sediments within urban ecosystem.

    PubMed

    Seleznev, Andrian A; Yarmoshenko, Ilia V; Ekidin, Alexey A

    2010-08-01

    The role of puddle sediments as a final depot of (137)Cs horizontal migration within the urban landscape is studied using the example of Ekaterinburg city, Russia. Radioactive contamination in the city appeared due to fallout after atmospheric testing of nuclear weapons and nuclear accidents. Contamination density of (137)Cs in the region was assessed from archive data to be about 5.1 kBq/m(2), of which the maximum activity concentration (<30 Bq/kg) is associated with the upper 15 cm soil layer. Results of the survey reported here indicate a mean (137)Cs activity concentration in puddle sediments of 80 Bq/kg, with a maximum value of 540 Bq/kg. It is estimated that horizontal migration has led to about a fourfold concentration of (137)Cs in puddle sediments. PMID:20417997

  18. Dietary items as possible sources of (137)Cs in large carnivores in the Gorski Kotar forest ecosystem, Western Croatia.

    PubMed

    Šprem, Nikica; Piria, Marina; Barišić, Domagoj; Kusak, Josip; Barišić, Delko

    2016-01-15

    The mountain forest ecosystem of Gorski Kotar is distant from any significant sources of environmental pollution, though recent findings have revealed that this region is among the most intense (137)Cs contaminated area in Croatia. Therefore, the aim of this study was to investigate (137)Cs and (40)K load in three large predator species in the mountain forest ecosystem. Radionuclides mass activities were determined by the gamma-spectrometric method in the muscle tissue of brown bear (47), wolf (7), lynx (1) and golden jackal (2). The highest (137)Cs mass activity was found in lynx (153 Bq kg(-1)), followed by brown bear (132 Bq kg(-1)), wolf (22.2 Bq kg(-1)), and golden jackal (2.48 Bq kg(-1)). Analysis of 63 samples of dietary items suggests that they are not all potentially dominant sources of (137)Cs for wildlife. The most important source of radionuclides for the higher parts of the food-chain from the study area were found to be the mushroom species wood hedgehog (Hydnum repandum), with a transfer factor TF of 5.166, and blueberry (Vaccinium myrtillus) as a plant species (TF=2.096). Food items of animal origin indicated higher mass activity of radionuclides and therefore are possible moderate bioindicators of environmental pollution. The results also revealed that possible unknown wild animal food sources are a caesium source in the study region, and further study is required to illuminate this issue. PMID:26556746

  19. Dietary items as possible sources of (137)Cs in large carnivores in the Gorski Kotar forest ecosystem, Western Croatia.

    PubMed

    Šprem, Nikica; Piria, Marina; Barišić, Domagoj; Kusak, Josip; Barišić, Delko

    2016-01-15

    The mountain forest ecosystem of Gorski Kotar is distant from any significant sources of environmental pollution, though recent findings have revealed that this region is among the most intense (137)Cs contaminated area in Croatia. Therefore, the aim of this study was to investigate (137)Cs and (40)K load in three large predator species in the mountain forest ecosystem. Radionuclides mass activities were determined by the gamma-spectrometric method in the muscle tissue of brown bear (47), wolf (7), lynx (1) and golden jackal (2). The highest (137)Cs mass activity was found in lynx (153 Bq kg(-1)), followed by brown bear (132 Bq kg(-1)), wolf (22.2 Bq kg(-1)), and golden jackal (2.48 Bq kg(-1)). Analysis of 63 samples of dietary items suggests that they are not all potentially dominant sources of (137)Cs for wildlife. The most important source of radionuclides for the higher parts of the food-chain from the study area were found to be the mushroom species wood hedgehog (Hydnum repandum), with a transfer factor TF of 5.166, and blueberry (Vaccinium myrtillus) as a plant species (TF=2.096). Food items of animal origin indicated higher mass activity of radionuclides and therefore are possible moderate bioindicators of environmental pollution. The results also revealed that possible unknown wild animal food sources are a caesium source in the study region, and further study is required to illuminate this issue.

  20. Aerosol residence times and changes in radioiodine-131I and radiocaesium-137 Cs activity over Central Poland after the Fukushima-Daiichi Nuclear reactor accident.

    PubMed

    Długosz-Lisiecka, Magdalena; Bem, Henryk

    2012-05-01

    The first detectable activities of radioiodine (131)I, and radiocaesium (134)Cs and (137)Cs in the air over Central Poland were measured in dust samples collected by the ASS-500 station in the period of 21(st) to 24(th) of March, 2011. However, the highest activity of both fission products, (131)I and (137)Cs: 8.3 mBq m(-3) and 0.75 mBq m(-3), respectively, were obtained in the samples collected on 30(th) March, i.e.∼18 days after the beginning of the fission products' discharge from the damaged units of the Fukushima Daiichi Nuclear Power Plant. The simultaneously determined corrected aerosol residence time for the same samples by (210)Pb/(210)Bi and (210)Pb/(210)Po methods was equal to 10 days. Additionally, on the basis of the activity ratio of two other natural cosmogenic radionuclides, (7)Be and (22)Na in these aerosol samples, it was possible to estimate the aerosol residence time at ∼150 days for the solid particles coming from the stratospheric fallout. These data, as well as the differences in the activity size distribution of (7)Be and (131)I in the air particulate matter, show, in contrast to the Chernobyl discharge, a negligible input of stratospheric transport of Fukushima-released fission products.

  1. Genetic effects of testicular incorporation of 137Cs in mice.

    PubMed

    Ramaiya, L K; Pomerantseva, M D; Chekhovich, A V; Lyaginskaya, A M; Kuznetsov, A S

    1994-08-01

    A comparative estimation of the frequencies of genetic disorders induced in germ cells of male mice by a single or long-term exposure to incorporated 137Cs or to external gamma-radiation has been carried out. The frequencies of dominant lethal mutations induced by a single exposure were similar with both types of radiation. In stem cell spermatogonia the frequency of reciprocal translocations was significantly lower in the case of single 137Cs administration than upon external gamma-radiation. Upon long-term administration the genetic efficiencies of both types of radiation were similar. PMID:7519738

  2. 134Cs: 137Cs and 106Ru: 137Cs ratios in intertidal sediments from the Cumbria and Lancashire coasts England

    NASA Astrophysics Data System (ADS)

    Stanners, D. A.; Aston, S. R.

    1981-10-01

    The distributions of 134Cs, 137Cs and 106Ru in intertidal surface sediments from the coasts of Cumbria and Lancashire, north-west England, are reported. The ratios of 134Cs: 137Cs and 106Ru: 137Cs activities have been used together with the isotopic composition of the Windscale radioactive effluents to examine the contamination history of sediments. Distinct differences between the activities and time of contamination of muds, silts and sands are found, and the apparent lag times of transport of radioactive wastes to different sediment localities are estimated. The relatively high activities in fine sediments reflect recent discharges indicating a rapid response to discharge, while the sands contain low levels of older contamination. Apparent lag times of up to 6 years are estimated for the study area; the transport to the south is generally more rapid than to the north. These results have consequences for the operation and interpretation of radiological monitoring in coastal areas.

  3. Fallout 137Cs in reindeer herders in Arctic Norway.

    PubMed

    Skuterud, Lavrans; Thørring, Håvard

    2015-03-01

    Reindeer herders in the Arctic were among the most heavily exposed populations to the global fallout from nuclear weapons testing in the 1950s and 1960s, due to high transfer of radionuclides in the lichens-reindeer-human food chain. Annual studies of (137)Cs in reindeer herders in Kautokeino, Norway, were initiated in 1965 to monitor radiation doses and follow environmental (137)Cs behavior. The (137)Cs concentrations declined from the peak in 1965 with effective half-times of 6-8 years, only interrupted by a temporary doubling in levels from 1986 to 1987 due to the Chernobyl fallout. During the period of 1950-2010 an average herder received an integrated effective dose from incorporated (137)Cs of about 18 mSv. This dose represents an insignificant increase in the risk for developing cancer. Health studies even show a significantly lower cancer incidence among Sámis and reindeer herders in northern Norway compared to other populations in the same area. PMID:25671344

  4. Fallout 137Cs in reindeer herders in Arctic Norway.

    PubMed

    Skuterud, Lavrans; Thørring, Håvard

    2015-03-01

    Reindeer herders in the Arctic were among the most heavily exposed populations to the global fallout from nuclear weapons testing in the 1950s and 1960s, due to high transfer of radionuclides in the lichens-reindeer-human food chain. Annual studies of (137)Cs in reindeer herders in Kautokeino, Norway, were initiated in 1965 to monitor radiation doses and follow environmental (137)Cs behavior. The (137)Cs concentrations declined from the peak in 1965 with effective half-times of 6-8 years, only interrupted by a temporary doubling in levels from 1986 to 1987 due to the Chernobyl fallout. During the period of 1950-2010 an average herder received an integrated effective dose from incorporated (137)Cs of about 18 mSv. This dose represents an insignificant increase in the risk for developing cancer. Health studies even show a significantly lower cancer incidence among Sámis and reindeer herders in northern Norway compared to other populations in the same area.

  5. Effect of redox potential on fixation of sup 137 Cs in lake sediment

    SciTech Connect

    Pardue, J.H.; DeLaune, R.D.; Patrick, W.H. Jr.; Whitcomb, J.H. )

    1989-11-01

    Fixation of 137Cs was determined in lake sediment suspensions under controlled redox potentials in the laboratory. The activity of previously added 137Cs on various clay sites was determined by time-series selective extractions. Monovalent cations, particularly NH+4, were much more effective at displacing 137Cs than divalent cations or Na+. Ammonium ion (NH+4) and Na+ were used to extract 137Cs from selective and non-selective 137Cs-binding sites, respectively. The activity of water-soluble 137Cs and Na-extractable 137Cs was significantly higher under anaerobic redox conditions (-200 mV), when soluble NH+4 concentrations in the anaerobic suspensions were 1000 microM or higher. Activities of 137Cs were highest (initially 40-50% of the 137Cs added) on the NH+4-extractable site. Over the long term, activities of NH+4-extractable 137Cs decreased linearly to below 10% as 137Cs was fixed on inter-lattice sites. Water-soluble 137Cs was significantly correlated with Na-extractable 137Cs in short-term experiments, suggesting the existence of an equilibrium between the different clay sites. High concentrations of NH+4 under anaerobic redox conditions could shift this equilibrium, resulting in increases in water-soluble 137Cs and increases in the activities of 137Cs bound on non-selective clay sites. Additional studies are necessary to evaluate the interaction of 137Cs with sulfides, iron oxides, and other reactive chemical species which may attenuate 137Cs in sediment.

  6. Transfer of 137Cs from Chernobyl debris and nuclear weapons fallout to different Swedish population groups.

    PubMed

    Rääf, C L; Hubbard, L; Falk, R; Agren, G; Vesanen, R

    2006-08-15

    Data from measurements on the body burden of (134)Cs, (137)Cs and (40)K in various Swedish populations between 1959 and 2001 has been compiled into a national database. The compilation is a co-operation between the Departments of Radiation Physics in Malmö and Göteborg, the National Radiation Protection Authority (SSI) and the Swedish Defense Research Agency (FOI). In a previous study the effective ecological half time and the associated effective dose to various Swedish populations due to internal contamination of (134)Cs and (137)Cs have been assessed using the database. In this study values of human body burden have been combined with data on the local and regional ground deposition of fallout from nuclear weapons tests (only (137)Cs) and Chernobyl debris (both (134)Cs and (137)Cs), which have enabled estimates of the radioecological transfer in the studied populations. The assessment of the database shows that the transfer of radiocesium from Chernobyl fallout to humans varies considerably between various populations in Sweden. In terms of committed effective dose over a 70 y period from internal contamination per unit activity deposition, the general (predominantly urban) Swedish population obtains 20-30 microSv/kBq m(-2). Four categories of populations exhibit higher radioecological transfer than the general population; i.) reindeer herders ( approximately 700 microSv/kBq m(-2)), ii.) hunters in the counties dominated by forest vegetation ( approximately 100 microSv/kBq m(-2)), iii.) rural non-farming populations living in sub-arctic areas (40-150 microSv/kBq m(-2)), and iv.) farmers ( approximately 50 microSv/kBq m(-2)). Two important factors determine the aggregate transfer from ground deposition to man; i.) dietary habits (intakes of foodstuff originating from natural and semi-natural ecosystems), and ii.) inclination to follow the recommended food restriction by the authorities. The transfer to the general population is considerably lower

  7. Contribution of Asian dust to atmospheric deposition of radioactive cesium ((137)Cs).

    PubMed

    Fukuyama, Taijiro; Fujiwara, Hideshi

    2008-11-01

    Both Asian dust (kosa) transported from the East Asian continent and locally suspended dust near monitoring sites contribute to the observed atmospheric deposition of (137)Cs in Japan. To estimate the relative contribution of these dust phenomena to the total (137)Cs deposition, we monitored weekly deposition of mineral particles and (137)Cs in spring. Deposition of (137)Cs from a single Asian dust event was 62.3 mBq m(-2) and accounted for 67% of the total (137)Cs deposition during the entire monitoring period. Furthermore, we found high (137)Cs specific activity in the Asian dust deposition sample. Although local dust events contributed to (137)Cs deposition, their contribution was considerably smaller than that of Asian dust. We conclude that the primary source of atmospheric (137)Cs in Japan is dust transported from the East Asian continent.

  8. [Effect of soil microflora on 137Cs transition to plants].

    PubMed

    Pareniuk, O Yu; Shavanova, K E; Ilienko, V V; Tytova, L V; Levchuk, S E; Gudkov, I N

    2015-01-01

    The impact of certain types of microorganisms on 137Cs transfer from the substrate into the plant was analyzed in the experiment on artificial mediums. It was found that certain types of microorganisms could either reduce or increase the ratio of 137Cs transfer from the substrate to the plant. It is shown that this property is independent of the localization of the microorganism on the surface of the root, for all the analyzed bacteria belonging to the rhizospheric group. Azotobacter chroococcum UKM B-6003 stimulated the radionuclide transfer to plants up to 1.5 times, while the best bacteria for reducing its accumulation is Burkholderia sp IMER-B1 -53 - 1.3 times in comparison with the control. It was shown that the strain Bacillus megaterium UKM B-5724 from the collection of the Institute of Microbiology and Virology of NASU has a high ability to accumulate radionuclides.

  9. Interlaboratory comparison on 137Cs activity concentration in fume dust

    NASA Astrophysics Data System (ADS)

    Tzika, Faidra; Hult, Mikael; Burda, Oleksiy; Arnold, Dirk; Sibbens, Goedele; Caro Marroyo, Belén; Gómez-Mancebo, Maria Belén; Peyrés, Virginia; Moser, Hannah; Ferreux, Laurent; Šolc, Jaroslav; Dryák, Pavel; Fazio, Aldo; Luca, Aurelian; Vodenik, Branko; Reis, Mario; Tyminski, Zbigniew; Klemola, Seppo

    2015-11-01

    A comparison was conducted, between 11 European National Metrology Institutes and EC-JRC, on measurement of 137Cs activity concentration in fume dust. As test material an activity standard produced from real contaminated fume dust was used. The standard material consisted of 13 cylindrical samples of compressed fume dust. The material contained 137Cs and 60Co of reference activity concentrations of (9.72±0.10) Bq/g and (0.450±0.018) Bq/g, respectively, for the reference date of 1 June 2013, determined using the comparison results. The organization and results of the intercomparison, as well as the process of obtaining reliable reference values are presented.

  10. A (137)Cs erosion model with moving boundary.

    PubMed

    Yin, Chuan; Ji, Hongbing

    2015-12-01

    A novel quantitative model of the relationship between diffused concentration changes and erosion rates using assessment of soil losses was developed. It derived from the analysis of surface soil (137)Cs flux variation under persistent erosion effect and based on the principle of geochemistry kinetics moving boundary. The new moving boundary model improves the basic simplified transport model (Zhang et al., 2008), and mainly applies to uniform rainfall areas which show a long-time soil erosion. The simulation results for this kind of erosion show under a long-time soil erosion, the influence of (137)Cs concentration will decrease exponentially with increasing depth. Using the new model fit to the measured (137)Cs depth distribution data in Zunyi site, Guizhou Province, China which has typical uniform rainfall provided a good fit with R(2) = 0.92. To compare the soil erosion rates calculated by the simple transport model and the new model, we take the Kaixian reference profile as example. The soil losses estimated by the previous simplified transport model are greater than those estimated by the new moving boundary model, which is consistent with our expectations. PMID:26327366

  11. Uptake of 137Cs and 90Sr in rice plants.

    PubMed

    Leung, J K C; Shang, Z R

    2003-02-01

    In order to study the transfer of water-borne 137Cs and 90Sr into rice plants, pot experiments were done by growing rice plants on soils taken from rice beds near two nuclear power plants: Qinshan Nuclear Power Plant and Daya Bay Nuclear Power Plant in China. The vertical migration of 137Cs and 90Sr in the soil samples was studied, and results show that almost all the contaminants were retained in the top 1 cm of soil with at most a few percent down to 3 cm of soil. The areal transfer factors of 137Cs and 90Sr were studied by adding various activity concentrations of the two radionuclides to the irrigation water and then measuring the activity concentration in the various rice tissues. The areal transfer factors were also analyzed for their dependence on soil characteristics, time and duration of the contamination. The areal transfer factors obtained in this study refer to the absorption of the fallout nuclides deposited in the irrigation water in a rice field as opposed to other studies that deal with uniform activity concentration in the soils.

  12. A (137)Cs erosion model with moving boundary.

    PubMed

    Yin, Chuan; Ji, Hongbing

    2015-12-01

    A novel quantitative model of the relationship between diffused concentration changes and erosion rates using assessment of soil losses was developed. It derived from the analysis of surface soil (137)Cs flux variation under persistent erosion effect and based on the principle of geochemistry kinetics moving boundary. The new moving boundary model improves the basic simplified transport model (Zhang et al., 2008), and mainly applies to uniform rainfall areas which show a long-time soil erosion. The simulation results for this kind of erosion show under a long-time soil erosion, the influence of (137)Cs concentration will decrease exponentially with increasing depth. Using the new model fit to the measured (137)Cs depth distribution data in Zunyi site, Guizhou Province, China which has typical uniform rainfall provided a good fit with R(2) = 0.92. To compare the soil erosion rates calculated by the simple transport model and the new model, we take the Kaixian reference profile as example. The soil losses estimated by the previous simplified transport model are greater than those estimated by the new moving boundary model, which is consistent with our expectations.

  13. Measurements and Observations of 134Cs and 137Cs around a Nuclear Power Plant in Busan, South Korea

    NASA Astrophysics Data System (ADS)

    Chong, H. Y.; Park, J. N.; Kim, J. S.

    2015-12-01

    The purpose of this study is to know the change of representative species 134Cs and 137Cs of artificial radionuclides from the nuclear power station nearby for the last five years(2010~2014). The Kori Nuclear Power Plant, nuclear power facility located near Busan, is located in the south-east coast of Korea and about 21km north-east away from the Haeundae and about 25km south away from the Ulsan. An administrative district is Jangan-eup, Gijang-gun, Busan, Korea. A point was selected on the basis of the "Environmental Radiation Monitoring Plan around Nuclear Power Plants" and periodically samples were collected and analyzed. The samples were collected from the soils of the surface in the Wolnae area (NW, 1.7km). The soil samples were analyzed by gamma spectrometer with High Purity Germanium detector (HPGe) of 40% relative efficiency and were measured for 80,000 sec. As a results of soil analysis, 137Cs were detected in samples only selected in March 2013. The activity concentration of 137Cs founded in the soil sample was 0.513±0.052Bq/kg-dry. In the other hands, the concentration of 137Cs in the year 2010, 2011, 2012, and 2014 were below the minimum detectable activity (MDA). 40K, natural radionuclides which is widely present, was detected in the soil samples and other artificial radionuclides were not detected. The result of overall comparison of the environmental radioactivity survey around Kori Nuclear Power Plant for the last five years is that radioactivity levels are within average range. However, it is necessary to continue to carefully observe a fine change in regional or the monthly radiation concentration.

  14. Effect of selective sorptive agents on leachability of {sup 137}Cs and {sup 90}Sr

    SciTech Connect

    Spence, R.D.

    1998-06-01

    Decades ago it was established that illite effectively improves {sup 137}Cs leach resistance. Subsequently, illite has become a standard ingredient used at Oak Ridge National Laboratory in grouts developed to stabilize {sup 137}Cs. Adding illite improves {sup 137}Cs leach resistance by three orders of magnitude, and increasing the illite concentration can add another order of magnitude improvement. Adding crystalline silicotitanate, a selective sorptive agent developed more recently for {sup 137}Cs, not only improves {sup 137}Cs leach resistance by an order-of-magnitude over that obtained using illite but also improves {sup 85}Sr leach resistance by two orders of magnitude.

  15. Fukushima 137Cs at the base of planktonic food webs off Japan

    NASA Astrophysics Data System (ADS)

    Baumann, Z.; Fisher, N. S.; Gobler, C. J.; Buesseler, K. O.; George, J. A.; Breier, C. F.; Nishikawa, J.

    2015-12-01

    The potential bioaccumulation of 137Cs in marine food webs off Japan became a concern following the release of radioactive contaminants from the damaged Fukushima nuclear power plant into the coastal ocean. Previous studies suggest that 137Cs activities increase with trophic level in pelagic food webs, however, the bioaccumulation of 137Cs from seawater to primary producers, to zooplankton has not been evaluated in the field. Since phytoplankton are frequently the largest component of suspended particulate matter (SPM) we used SPM concentrations and particle-associated 137Cs to understand bioaccumulation of 137Cs in through trophic pathways in the field. We determined particle-associated 137Cs for samples collected at 20 m depth from six stations off Japan three months after the initial release from the Fukushima nuclear power plant. At 20 m SPM ranged from 0.65 to 1.60 mg L-1 and rapidly declined with depth. The ratios of particulate organic carbon to chlorophyll a suggested that phytoplankton comprised much of the SPM in these samples. 137Cs activities on particles accounted for on average 0.04% of the total 137Cs in seawater samples, and measured concentration factors of 137Cs on small suspended particles were comparatively low (∼102). However, when 137Cs in crustacean zooplankton was derived based only on modeling dietary 137Cs uptake, we found predicted and measured 137Cs concentrations in good agreement. We therefore postulate the possibility that the dietary route of 137Cs bioaccumulation (i.e., phytoplankton ingestion) could be largely responsible for the measured levels in the copepod-dominated (%) zooplankton assemblages in Japanese coastal waters. Finally, our data did not support the notion that zooplankton grazing on phytoplankton results in a biomagnification of 137Cs.

  16. Root endophytic bacteria of a (137)Cs and Mn accumulator plant, Eleutherococcus sciadophylloides, increase (137)Cs and Mn desorption in the soil.

    PubMed

    Yamaji, Keiko; Nagata, Satoshi; Haruma, Toshikatsu; Ohnuki, Toshihiko; Kozaki, Tamotsu; Watanabe, Naoko; Nanba, Kenji

    2016-03-01

    We found that root endophytes of (137)Cs accumulator plant produce siderophores, resulting in the desorption of (137)Cs from the contaminated soil collected at Fukushima, Japan. We selected an endemic Japanese deciduous tree, Eleutherococcus sciadophylloides (Franch. et Sav), that accumulates high concentrations of (137)Cs and Mn. Root endophytic bacteria were isolated from E. sciadophylloides and microbial siderophore production was evaluated via chrome azurol S (CAS) Fe and CAS Al assays. Of the 463 strains that we isolated, 107 (23.1%) produced the siderophores. Using eight strains that showed high siderophore production in our assays, we examined desorption of (137)Cs, Mn, Fe and Al by the bacterial culture filtrates from (137)Cs-contaminated soil after decomposing the soil organic matter using hydrogen peroxide. We found (137)Cs and Mn desorption concomitant with Al and Fe desorption, as well as a decrease of pH. We also detected succinic acid, a well-known siderophore, in the bacterial culture filtrates of our two root endophytic bacteria. Our results strongly suggest that the root endophytic bacteria of E. sciadophylloides produce the siderophores that enhance (137)Cs and Mn desorption in the rhizosphere, making the resulting (137)Cs and Mn ions easier for E. sciadophylloides to absorb from the rhizosphere. PMID:26760221

  17. Root endophytic bacteria of a (137)Cs and Mn accumulator plant, Eleutherococcus sciadophylloides, increase (137)Cs and Mn desorption in the soil.

    PubMed

    Yamaji, Keiko; Nagata, Satoshi; Haruma, Toshikatsu; Ohnuki, Toshihiko; Kozaki, Tamotsu; Watanabe, Naoko; Nanba, Kenji

    2016-03-01

    We found that root endophytes of (137)Cs accumulator plant produce siderophores, resulting in the desorption of (137)Cs from the contaminated soil collected at Fukushima, Japan. We selected an endemic Japanese deciduous tree, Eleutherococcus sciadophylloides (Franch. et Sav), that accumulates high concentrations of (137)Cs and Mn. Root endophytic bacteria were isolated from E. sciadophylloides and microbial siderophore production was evaluated via chrome azurol S (CAS) Fe and CAS Al assays. Of the 463 strains that we isolated, 107 (23.1%) produced the siderophores. Using eight strains that showed high siderophore production in our assays, we examined desorption of (137)Cs, Mn, Fe and Al by the bacterial culture filtrates from (137)Cs-contaminated soil after decomposing the soil organic matter using hydrogen peroxide. We found (137)Cs and Mn desorption concomitant with Al and Fe desorption, as well as a decrease of pH. We also detected succinic acid, a well-known siderophore, in the bacterial culture filtrates of our two root endophytic bacteria. Our results strongly suggest that the root endophytic bacteria of E. sciadophylloides produce the siderophores that enhance (137)Cs and Mn desorption in the rhizosphere, making the resulting (137)Cs and Mn ions easier for E. sciadophylloides to absorb from the rhizosphere.

  18. Risk assessment of distribution coefficient from 137Cs measurements.

    PubMed

    Külahci, Fatih; Sen, Zekai

    2009-02-01

    Classically distribution coefficient is defined as the ratio of solid total element concentration to surface water total concentration. This coefficient is obtained from the ion measurements in the Keban Dam, Turkey, which supplies water for domestic, irrigation and hydroelectric energy generation purposes. The measurements of 137Cs are carried out in 40 different sites and the general risk formulation and application is achieved for the distribution coefficient. The models are of exponential type and the spatial independence of the data is considered. Various charts are prepared for a set of risk levels as 5%, 10%, 20%, 25%, and 50%.

  19. Ecological half-time and effective dose from chernobyl debris and from nuclear weapons fallout of 137Cs as measured in different Swedish populations.

    PubMed

    Rääf, C L; Hubbard, L; Falk, R; Agren, G; Vesanen, R

    2006-05-01

    The fallout in Sweden of radiocesium from nuclear weapons tests during the 1960's (137Cs) and from the Chernobyl accident in 1986 (134Cs and 137Cs) has transferred to humans through different ecological pathways. Data from whole-body burden measurements of 134Cs, 137Cs, and 40K in various Swedish populations between 1964 and 2002 have been compiled. This database enables an evaluation of the temporal and geographical dependence of the transfer of radiocesium from ground deposition to humans and the associated absorbed dose. The body burdens of 137Cs gradually decrease after the peak values reached in 1965 from nuclear weapons fallout and in 1987 from the Chernobyl fallout, but at a varying rate depending on the population. Assuming a dual exponential decrease, a short-term component of typically 1-2 y and a long-term component of 5-10 y are found in urban populations in Sweden. Among reindeer herders and hunters the effective ecological half-time is mono-exponential with a half-time of 5-7 y. The estimated time-integrated effective dose to an individual during a period of 50 y from the Chernobyl fallout is, on average, approximately 10 mSv for reindeer herders, which is 10-100 times higher than the estimated dose received by urban populations in the three major Swedish urban areas (Malmö, Göteborg, and Stockholm).

  20. Concentration of (137)Cs in soil across Nebraska.

    PubMed

    Weesner, Alexandra Palensky; Fairchild, Robert W

    2008-06-01

    Atmospheric nuclear weapons testing from 1945 through 1980 produced radioactive fallout that was transported by stratospheric winds and deposited unevenly around the world. The accident at Chernobyl in 1986 also contributed to the fallout in some locations. The (137)Cs activity concentration from fallout has been measured as a function of depth in soil samples from five different locations across Nebraska. Soil samples 2-cm thick down to a depth of 30 cm were collected in Brown, Dawes, Lancaster, Red Willow, and Thurston Counties. Samples taken from each of the sites were dried, sieved, and counted using an HPGe gamma spectroscopy system to measure the activity concentration of (137)Cs at each depth in the soil. Activity concentrations as high as 216 Bq kg(-1) were measured in the samples. Dry soil bulk densities were calculated for each site based on soil type and used to calculate the area density of deposition. Area deposition densities up to 13,100 Bq m(-2) were measured, consistent with published estimates.

  1. Potential of largemouth bass as vectors of 137Cs dispersal.

    PubMed

    Paller, M H; Fletcher, D E; Jones, T; Dyer, S A; Isely, J J; Littrell, J W

    2005-01-01

    We conducted a radio telemetry study on the movements of potentially contaminated largemouth bass between Steel Creek, a restricted access (137)Cs contaminated stream on the Savannah River Site (located in South Carolina, USA), and the publicly accessible Savannah River. Largemouth bass were relatively mobile in lower Steel Creek and the portion of the Savannah River near Steel Creek, and there was considerable movement between these two habitats. Largemouth bass had home ranges of about 500 linear meters of shoreline in the Savannah River but sometimes moved long distances. Such movements occurred primarily during the spawning season, largely upstream, and increased when water levels were changing or elevated. However, approximately 90% of the largemouth bass observations were within 10 km of Steel Creek. The total quantity of (137)Cs transported into the Savannah River by largemouth bass was much less than transported by water and suspended sediments discharged from Steel Creek. We conclude that largemouth bass from the Savannah River Site are unlikely to be responsible for long distance dispersal of substantial radiological contamination in the Savannah River.

  2. The distribution of fallout {sup 137}Cs in Costa Rica

    SciTech Connect

    Salazar, A.; Mora, P.

    1996-08-01

    Baseline levels of {sup 137}Cs on different sites throughout the Costa Rican territory are presented in this study from local and undisturbed soils. They are believed to represent the fallout input to the land surface. Seventy samples were collected from September 1991 to December 1993, and analyzed by gamma spectroscopy. The territory was divided in three regions, Caribbean, Pacific, and Central, based on meteorological and geographical conditions to study spatial distribution of cesium. The results show a higher activity in the Caribbean region perhaps due to the wind influence and higher rain precipitation throughout the year. No relevant time variation of the activity levels of reach location was found. The highest value of 17.6 Bq kg{sup {minus}1} of {sup 137}Cs is compared with it generalized derived limit, being only 1.97% of the generalized derived limit value. The mean country activity value ranges from 0.4 to 17.8 Bq kg{sup {minus}1} with an average of 3.7 Bq kg{sup {minus}1}. 10 refs., 4 figs., 1 tab.

  3. Reconstruction of 137Cs activity in the ocean following the Fukushima Daiichi Nuclear Power Plant Accident

    NASA Astrophysics Data System (ADS)

    Tsumune, Daisuke; Aoyama, Michio; Tsubono, Takaki; Tateda, Yutaka; Misumi, Kazuhiro; Hayami, Hiroshi; Toyoda, Yasuhiro; Maeda, Yoshiaki; Yoshida, Yoshikatsu; Uematsu, Mitsuo

    2014-05-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant following the earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways, direct release from the accident site and atmospheric deposition. We reconstructed spatiotemporal variability of 137Cs activity in the ocean by the comparison model simulations and observed data. We employed a regional scale and the North Pacific scale oceanic dispersion models, an atmospheric transport model, a sediment transport model, a dynamic biological compartment model for marine biota and river runoff model to investigate the oceanic contamination. Direct releases of 137Cs were estimated for more than 2 years after the accident by comparing simulated results and observed activities very close to the site. The estimated total amounts of directly released 137Cs was 3.6±0.7 PBq. Directly release rate of 137Cs decreased exponentially with time by the end of December 2012 and then, was almost constant. The daily release rate of 137Cs was estimated to be 3.0 x 1010 Bq day-1 by the end of September 2013. The activity of directly released 137Cs was detectable only in the coastal zone after December 2012. Simulated 137Cs activities attributable to direct release were in good agreement with observed activities, a result that implies the estimated direct release rate was reasonable, while simulated 137Cs activities attributable to atmospheric deposition were low compared to measured activities. The rate of atmospheric deposition onto the ocean was underestimated because of a lack of measurements of dose rate and air activity of 137Cs over the ocean when atmospheric deposition rates were being estimated. Observed 137Cs activities attributable to atmospheric deposition in the ocean helped to improve the accuracy of simulated atmospheric deposition rates. Although there is no observed data of 137Cs activity in the ocean from 11 to 21 March 2011, observed data of

  4. Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils.

    PubMed

    Vinichuk, M; Mårtensson, A; Ericsson, T; Rosén, K

    2013-01-01

    The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of (137)Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with (137)Cs was investigated, with non-mycorrhizal quinoa included as a "reference" plant. The effect of cucumber and ryegrass inoculation with AM fungi on (137)Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and (137)Cs uptake increased on loamy sand and loamy soils. The total (137)Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of (137)Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. PMID:22939950

  5. The use of tree bark as long term biomonitor of (137)Cs deposition.

    PubMed

    Cosma, Constantin; Iurian, Andra-Rada; Incze, Reka; Kovacs, Tibor; Žunić, Zora S

    2016-03-01

    Airborne (137)Cs originated from the nuclear tests in the atmosphere and from the Chernobyl nuclear disaster was retained by the trees biomass and nowadays it can still be found in various concentrations in tree barks from Romania and other European countries. This study brings the first results of (137)Cs presence in tree bark from Romania on different considerations: (i) data dispersion in spruce and oak bark from NW, SW and central Romania, and the spatial variability of (137)Cs within oak and spruce bark from a natural protected forest area from Balvanyos area (Covasna County), known to be highly affected by the Chernobyl nuclear release; (ii) comparison of (137)Cs content in different tree bark species (oak, spruce, poplar and cherry); (iii) differences in (137)Cs concentrations with the bark depth layers and around the tree trunk; and (iv) comparison of mean (137)Cs values in spruce/oak bark from Romania with data from other European countries. PMID:26771244

  6. REMOVAL OF 137Cs FROM DISSOLVED HANFORD TANK SALTCAKE BY TREATMENT WITH IONSIV IE-911

    SciTech Connect

    Rapko, Brian M.; Sinkov, Serguei I.; Levitskaia, Tatiana G.

    2005-03-01

    This paper describes the preparation of a 137Cs-depleted form of dissolved Hanford tank saltcake. A composite feed solution was treated with IONSIV{reg_sign} IE-911, which effectively reduced the concentration of 137Cs. This allowed for subsequent testing of waste immobilization without significant radiological hazard. Limited characterization of the initial feed solution and a more extensive characterization of the 137Cs-depleted material also are provided.

  7. Inferring the chemical form of 137Cs deposited by the Fukushima Dai-ichi Nuclear Power Plant accident by measuring (137)Cs incorporated into needle leaves and male cones of Japanese cedar trees.

    PubMed

    Kanasashi, Tsutomu; Takenaka, Chisato; Sugiura, Yuki

    2016-05-15

    We hypothesized that the water-soluble (ionic) and water-insoluble (stable) radiocesium from the initial fallout of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident was distributed in various proportions in the surrounding areas and that this distribution was reflected in the trees that suffered deposition from the initial fallout. This study attempted to evaluate local variations in the chemical form of (137)Cs derived from the initial fallout of the FDNPP accident and whether its chemical form affected the radiocesium concentration in the tissues currently growing in trees, even after the initial fallout ceased. For these estimations, the ratio between the (137)Cs concentration in Cryptomeria japonica needle leaves in the tree crown, which existed before the FDNPP accident and subsequently directly exposed to the initial fallout ((137)Cs pre-accident N), and the amount of (137)Cs in the initial fallout itself ((137)Cs fallout) was determined ((137)Cs pre-accident N/(137)Cs fallout) at 66 sites. In addition, the (137)Cs ratios between the male cones produced in 2012 ((137)Cs male cone) and needle leaves that had elongated in the spring of 2011 ((137)Cs 2011N) was determined at 82 sites ((137)Cs male cone/(137) Cs 2011N). Most of the sites with lower (137)Cs pre-accident N /(137)Cs fallout ratios were distributed in eastern Fukushima, relatively close to the Pacific Ocean coastline. Lower (137)Cs pre-accident N/(137)Cs fallout and higher (137)Cs malecone/(137)Cs 2011N were found to be associated with higher proportions of (137)Cs in ionic forms. These observations are consistent with the hypothesis, and likely reflect regional variations in the chemical form of the deposited radiocesium.

  8. Inferring the chemical form of 137Cs deposited by the Fukushima Dai-ichi Nuclear Power Plant accident by measuring (137)Cs incorporated into needle leaves and male cones of Japanese cedar trees.

    PubMed

    Kanasashi, Tsutomu; Takenaka, Chisato; Sugiura, Yuki

    2016-05-15

    We hypothesized that the water-soluble (ionic) and water-insoluble (stable) radiocesium from the initial fallout of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident was distributed in various proportions in the surrounding areas and that this distribution was reflected in the trees that suffered deposition from the initial fallout. This study attempted to evaluate local variations in the chemical form of (137)Cs derived from the initial fallout of the FDNPP accident and whether its chemical form affected the radiocesium concentration in the tissues currently growing in trees, even after the initial fallout ceased. For these estimations, the ratio between the (137)Cs concentration in Cryptomeria japonica needle leaves in the tree crown, which existed before the FDNPP accident and subsequently directly exposed to the initial fallout ((137)Cs pre-accident N), and the amount of (137)Cs in the initial fallout itself ((137)Cs fallout) was determined ((137)Cs pre-accident N/(137)Cs fallout) at 66 sites. In addition, the (137)Cs ratios between the male cones produced in 2012 ((137)Cs male cone) and needle leaves that had elongated in the spring of 2011 ((137)Cs 2011N) was determined at 82 sites ((137)Cs male cone/(137) Cs 2011N). Most of the sites with lower (137)Cs pre-accident N /(137)Cs fallout ratios were distributed in eastern Fukushima, relatively close to the Pacific Ocean coastline. Lower (137)Cs pre-accident N/(137)Cs fallout and higher (137)Cs malecone/(137)Cs 2011N were found to be associated with higher proportions of (137)Cs in ionic forms. These observations are consistent with the hypothesis, and likely reflect regional variations in the chemical form of the deposited radiocesium. PMID:26990074

  9. Deposition of 137Cs in Rokkasho, Japan and its relation to Asian dust.

    PubMed

    Akata, Naofumi; Hasegawa, Hidenao; Kawabata, Hitoshi; Chikuchi, Yuki; Sato, Tadahiro; Ohtsuka, Yoshihito; Kondo, Kunio; Hisamatsu, Shun'ichi

    2007-01-01

    Biweekly atmospheric depositions of (137)Cs were measured in Rokkasho, Aomori, Japan from March 2000 to March 2006 to study recent (137)Cs deposition. Although the deposition level was generally lower than the detectable limit, deposition samples collected in spring occasionally had measurable levels of (137)Cs. The annual (137)Cs deposition from 2001 to 2005 was 0.04-0.69 Bq m(-2) with a mean value of 0.27 Bq m(-2). Depositions of insoluble Al, Fe and Ti were strongly correlated with the (137)Cs deposition, suggesting that suspension of soil particles was the main source of the recent (137)Cs deposition. Asian dust events were coincident with some of the significant (137)Cs depositions in spring. It was found that the ratios of (137)Cs/Al and Fe/Al could be used as indices for discriminating Asian dust from suspension of the local surface soil. Backward trajectory analysis suggested southern Mongolian and northeastern China regions as sources of the significant (137)Cs depositions.

  10. 137Cs contamination of Techa river flood plain in Brodokalmak settlement.

    PubMed

    Chesnokov, A V; Govorun, A P; Ivanitskaya, M V; Liksonov, V I; Shcherbak, S B

    1999-06-01

    137Cs contamination of the Techa river flood plain inside the Brodokalmak settlement has been mapped. The collimated scintillated detector technique was used for 137Cs deposit measurements. The 137Cs contamination is very heterogeneous. A comparison of this technique with the traditional sample method was performed at selected locations. The sampling data are in good agreement with in-situ data. Soil surface activity of 90Sr was determined from the samples. It was shown that 137Cs contamination correlates with 90Sr contamination within the flood plain of the settlement.

  11. 137Cs uptake with cafeteria food after the Chernobyl accident

    SciTech Connect

    Voigt, G.; Paretzke, H.G. )

    1992-11-01

    After the Chernobyl accident, the activity concentrations of radiocesium were measured in both the meals served at the cafeteria of a research center and in the employees eating there. The time-dependent means of monthly 137Cs activities in meals and people show a similar distribution pattern with highest values between March and July 1987, i.e., only 1 y after the accident. In meals, the highest activities were found when the menu consisted of pork, milk, or milk products. The 50-y cumulative effective dose calculated from the whole-body measurements is 0.21 mSv for male and 0.15 mSv for female employees. Cafeteria food contributed only a small share to this exposure.

  12. Upward mobilization of 137Cs in surface soils of Chamaecyparis obtusa Sieb. et Zucc. (hinoki) plantation in Japan.

    PubMed

    Fukuyama, Taijiro; Takenaka, Chisato

    2004-01-01

    The use of 137Cs has recently been adopted to estimate erosion in hinoki plantations in Japan. However, there have been several reports of the upward mobilization of 137Cs in forest humus layers. In this study, the vertical distribution of 137Cs within the soil profile was measured in a hinoki plantation. In order to confirm the upward migration of 137Cs from mineral soil to fresh surface litter and to identify mechanisms of the transfer, changes in 137Cs specific activity in the contents of litterbags were examined in a hinoki plantation. A controlled laboratory experiment was also conducted to assess the effect of microbial activity on the upward migration of 137Cs. As a result, the higher 137Cs activities in the surface organic layer of a hinoki plantation than in fresh litter and the increasing 137Cs total content of litterbags with time demonstrated the upward mobilization of 137Cs from mineral soil to the surface organic layer. Physical movement of soil particles by raindrop splash was considered an important process in 137Cs upward migration. The results of our laboratory experiment indicate an influence from soil microbial activity on the upward mobilization of 137Cs. Thus, upward migration of 137Cs and constant litter removal by runoff may induce 137Cs loss from steep forested catchments and underestimation of the 137Cs inventory leading to the overestimation of soil redistribution rates.

  13. Apparatus development for measurement of (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident.

    PubMed

    Kajimoto, Tsuyoshi; Endo, Satoru; Tanaka, Kenichi; Okashiro, Yasuharu; Kai, Hiroaki; Fujii, Syuuji; Mishima, Atsushi; Matsubara, Takahide; Yoshida, Shinji

    2016-09-01

    We developed an apparatus containing a NaI(Tl) scintillator to measure the (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident. The unfolding method with the least-squares technique was used to determine the radioactivity. Detector responses for each radionuclide in soil were calculated with EGS5 code for the unfolding method. The radionuclides that were measured were (40)K, (134)Cs, (137)Cs, (208)Tl, (214)Bi, and (228)Ac. The measured spectrum agreed well with the spectrum calculated from the response matrix and measured radioactivities. The unfolding method allows us to use the NaI(Tl) scintillator despite the overlap of peaks.

  14. Apparatus development for measurement of (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident.

    PubMed

    Kajimoto, Tsuyoshi; Endo, Satoru; Tanaka, Kenichi; Okashiro, Yasuharu; Kai, Hiroaki; Fujii, Syuuji; Mishima, Atsushi; Matsubara, Takahide; Yoshida, Shinji

    2016-09-01

    We developed an apparatus containing a NaI(Tl) scintillator to measure the (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident. The unfolding method with the least-squares technique was used to determine the radioactivity. Detector responses for each radionuclide in soil were calculated with EGS5 code for the unfolding method. The radionuclides that were measured were (40)K, (134)Cs, (137)Cs, (208)Tl, (214)Bi, and (228)Ac. The measured spectrum agreed well with the spectrum calculated from the response matrix and measured radioactivities. The unfolding method allows us to use the NaI(Tl) scintillator despite the overlap of peaks. PMID:27289189

  15. The extremely high 137Cs inventory in the Sulu Sea: a possible mechanism.

    PubMed

    Yamada, Masatoshi; Wang, Zhong-Liang; Zheng, Jian

    2006-01-01

    Large-volume seawater samples were collected in the Sulu and South China Seas and their (137)Cs activities were determined by gamma-ray spectrometry using a low background type high-purity Ge detector. Vertical distributions of (137)Cs activity showed an exponential decrease in the South China Sea, whereas a subsurface maximum at 200m depth and monotonic decrease below 300m were observed in the Sulu Sea. A significant difference in intermediate water (137)Cs activities in the 500-2000m depth was observed between the Sulu and South China Seas, i.e., the (137)Cs activities in the Sulu Sea were remarkably higher than those in the South China Sea. The difference in the (137)Cs inventory below 500m was approximately 1200Bqm(-2) between the Sulu and South China Seas. The (137)Cs total inventory of 3200Bqm(-2) in the Sulu Sea was 5.7 times higher than that expected from global fallout. A possible mechanism controlling this extremely high (137)Cs total inventory may be inflows of the (137)Cs rich water masses through the Luzon Strait, lateral transport across the Mindoro Strait into the Sulu Sea, and then subduction into the deep layer in the basin.

  16. Uptake and elimination of {sup 137}Cs by climbing perch (Anabus testudineus)

    SciTech Connect

    Malek, M.A.

    1999-12-01

    This work describes the uptake and retention/biological elimination of {sup 137}Cs by climbing perch (Anabus testudineus) under laboratory conditions. The accumulated {sup 137}Cs concentration in the whole body of the fish was measured at certain intervals up to 38 d. A significant accumulation of {sub 137}Cs was not achieved by the end of the experiment. The bioaccumulation factors and the distribution of the radionuclide in edible parts of the fish were determined. The effective half-life of {sup 137}Cs in the fish species was found to be {approximately}147 d (average) for elderly and adult fishes and {approximately}300 d for younger fishes. Accumulation of {sup 137}Cs in the edible parts of the fish was found to be {approximately}77% of whole body accumulation.

  17. [sup 137]Cs levels in deer following the Three Mile Island accident

    SciTech Connect

    Field, R.W. )

    1993-06-01

    White-tailed deer (Odocoileus virgianus) tongues were assayed to assess whether or not significant widespread [sup 137]Cs contamination occurred in the vicinity of Three Mile Island Nuclear Station as a result of the 1979 accident. White-tailed deer tongues harvested from 10 Pennsylvania counties more than 88 km away from Three Mile Island had significantly higher [sup 137]Cs levels than deer tongues harvested from counties surrounding the nuclear plant. The mean deer tongue [sup 137]Cs levels found in Pennsylvania white-tailed deer were lower than [sup 137]Cs levels found in deer from other parts of the US sampled shortly after culmination of major atmospheric nuclear testing. These findings support the conclusions of previous studies suggesting that only minimal quantities of [sup 137]Cs escaped from the damaged Three Mile Island plant after the accident.

  18. 137Cs as a tracer of recent sedimentary processes in Lake Michigan

    USGS Publications Warehouse

    Cahill, R.A.; Steele, J.D.

    1986-01-01

    To determine recent sediment movement, we measured the levels of 137Cs (an artificial radionuclide produced during nuclear weapons testing) of 118 southern Lake Michigan samples and 27 in Green Bay. These samples, taken from 286 grab samples of the upper 3 cm of sediment, were collected in 1975 as part of a systematic study of Lake Michigan sediment. 137Cs levels correlated well with concentrations of organic carbon, lead, and other anthropogenic trace metals in the sediment. 137Cs had a higher correlation with silt-sized than with clay-sized sediment (0.55 and 0.46, respectively). Atmospherically derived 137Cs and trace metals are being redistributed by sedimentary processes in Lake Michigan after being incorporated in suspended sediment. We determined a distribution pattern of 137Cs that represents areas of southern Lake Michigan where sediment deposition is occurring. ?? 1986 Dr W. Junk Publishers.

  19. 137Cs levels in deer following the Three Mile Island accident.

    PubMed

    Field, R W

    1993-06-01

    White-tailed deer (Odocoileus virgianus) tongues were assayed to assess whether or not significant widespread 137Cs contamination occurred in the vicinity of Three Mile Island Nuclear Station as a result of the 1979 accident. White-tailed deer tongues harvested from 10 Pennsylvania counties more than 88 km away from Three Mile Island had significantly higher 137Cs levels than deer tongues harvested from counties surrounding the nuclear plant. The mean deer tongue 137Cs levels found in Pennsylvania white-tailed deer were lower than 137Cs levels found in deer from other parts of the U.S. sampled shortly after culmination of major atmospheric nuclear testing. These findings support the conclusions of previous studies suggesting that only minimal quantities of 137Cs escaped from the damaged Three Mile Island plant after the accident. PMID:8491625

  20. 137Cs in soil and fallout around Zagreb (Croatia) at the time of the Fukushima accident.

    PubMed

    Šoštarić, Marko; Petrinec, Branko; Babić, Dinko

    2013-12-01

    This paper addresses the noticeable increase of 137Cs activity concentrations in soil and fallout in the area surrounding Zagreb (Croatia) that occurred at the time of the 2011 Fukushima accident. This topic is important for public health as 137Cs is highly toxic due to its long half-life of radioactive decay and chemical similarity to potassium. 137Cs concentrations in fallout were much greater than in soil, but remained present longer in the latter. While being detectable in our measurements, 137Cs did not spread through the food chain in amounts exceeding the maximum allowed level of radioactive food contamination. However, more thorough and consistent measurements need to be done in order to establish the precise activity trends of 137Cs in Zagreb soil and fallout.

  1. 137Cs levels in deer following the Three Mile Island accident.

    PubMed

    Field, R W

    1993-06-01

    White-tailed deer (Odocoileus virgianus) tongues were assayed to assess whether or not significant widespread 137Cs contamination occurred in the vicinity of Three Mile Island Nuclear Station as a result of the 1979 accident. White-tailed deer tongues harvested from 10 Pennsylvania counties more than 88 km away from Three Mile Island had significantly higher 137Cs levels than deer tongues harvested from counties surrounding the nuclear plant. The mean deer tongue 137Cs levels found in Pennsylvania white-tailed deer were lower than 137Cs levels found in deer from other parts of the U.S. sampled shortly after culmination of major atmospheric nuclear testing. These findings support the conclusions of previous studies suggesting that only minimal quantities of 137Cs escaped from the damaged Three Mile Island plant after the accident.

  2. Spatial pattern of 137Cs in soils in a mixed deciduous forest in Fukushima, Japan

    NASA Astrophysics Data System (ADS)

    Takada, M.; Yamada, T.; Takahara, T.; Okuda, T.

    2015-12-01

    Spatial heterogeneity of 137Cs contamination was studied in a forest floor of Fukushima region, c.a. 40 km NW of Fukushima Daiichi Nuclear Power Plant (FDNPP) focusing on downwards flow from forest canopy via stemflow and throughfall which play major role in determining spatial contamination of 137Cs after the FNDP accident. Setting a study plot (400 m2) in a secondary mixed deciduous forest, dominated by Quercus crispula and Abies firma in canopy layer in August and November 2014, we sampled the souk from surface to 5 cm in depth of soils and measured 137Cs in every 2 m grids and at tree stem bases. The total estimated activity of 137Cs in soil within the study plot was approximately 210 kBq/m2, but showed large spatial heterogeneity showing 30 times of difference between the lowest and highest activities. The activity decreased with increasing distances from tree stem bases. High activity around tree stem bases was presumably due to the stemflow containing 137Cs seeped into soil only around tree stem bases that raised radioactivity in soil locally in the areas. Relatively low activity away from trees (outside canopies) may be due to small effects of stemflow and throughfall. Activity of 137Cs around bases of deciduous broadleaf trees increased with increasing the tree size. Because larger trees have higher potentials to capture larger amount of 137Cs on the tree surface, cumulative activity of 137Cs included in stemflow may increase with increasing the tree size. However evergreen coniferous tree species (Abies firma) did not show such a pattern relating to the tree size. The difference is assumed to be affected by phenological characteristics as the accident happened in winter and deciduous broadleaf trees did not have leaves and 137Cs deposited on tree bodies, while evergreen coniferous tree had leaves and 137Cs was intercepted by the canopies.

  3. Temporal variation of 137Cs water column inventory in the North Pacific since the 1960s.

    PubMed

    Aoyama, M; Hirose, K

    2003-01-01

    The temporal variation of water column inventories of 137Cs in the North Pacific since the 1960s was examined based on the analysis of the 137Cs profiles in HAM database. 137Cs in seawater in the North Pacific have originated mainly from global fallout from atmospheric nuclear weapons tests, which occurred in the early 1960s. In the 1960s, both the meridional distribution of 137Cs inventory in the North Pacific and that of fallout on land stations showed mid-latitude maximum. The region with higher deposition at land stations, however, was more northern than the latitudes where the 137Cs inventory in the North Pacific showed a maximum. The difference of the latitude where maximum 137Cs deposition/inventory was observed reflects the difference of the geographical distribution of the precipitation amount in the Pacific and Atlantic Oceans followed by the different warm current systems in each ocean. A good positive relation between 137Cs inventory and annual precipitation amount was discovered in the ocean stations at the middle latitude in the North Pacific. The horizontal distribution of 137Cs inventories at the middle latitudes in the North Pacific is characterized as west-high and east-low in the early 1960s, which was basically controlled by the distribution of annual precipitation amount. Eastward advection, then, modified it to be less difference in 1966-1967 after the highest deposition periods in 1963-1965. In the 1970s and 1980s, increases of the 137Cs inventory at the lower latitude of 10-20 deg. N are found. Surface and subsurface southward transports are considered as the source of this increasing 137Cs inventory.

  4. Estimation of vertical migration velocity of (137)Cs in the Mount IDA/Kazdagi, Turkey.

    PubMed

    Karadeniz, Özlem; Çakır, Rukiye; Karakurt, Hidayet

    2015-08-01

    This paper presents the results obtained from a radioecological study carried out in the forest sites of Mount IDA (Kazdagi)/Edremit, Turkey. For 118 soil profiles, the depth distribution of (137)Cs activity was established by fitting the experimental points to an exponential, a gaussian or a log-normal function. The relaxation lengths were in the range of 1.09-16.7 cm with a mean of 5.73 cm, showing a slow transport and a strong retention capacity of (137)Cs even after the 26-y period of Chernobyl accident. From the data for the vertical distribution of (137)Cs in soil profiles, the mean annual migration velocity of (137)Cs was in the range of 0.11-0.62 cm year(-1) with a mean of 0.30 cm year(-1). Statistically significant correlations between the thickness of the humus layer and the mean annual velocity of (137)Cs were found for both coniferous and mixed forest sites. The mean annual velocity of (137)Cs in the forests sites with Pinus nigra var pallasiana was significantly higher than sites with Pinus brutia. External dose-rates from the (137)Cs in forest soils were estimated using a conversion factor used in many studies and comprised with the external dose-rates determined according to the vertical distribution of (137)Cs within the soil depth profiles. It is clearly seen that both levels and spatial distribution patterns of the external dose-rates from (137)Cs were influenced considerably with the vertical migration rate and the vertical distribution of (137)Cs.

  5. [Distribution of 137Cs and relative influencing factors on typical karst sloping land].

    PubMed

    Zhang, Xiao-Nan; Wang, Ke-Lin; Zhang, Wei; Chen, Hong-Song; He, Xun-Yang; Zhang, Xin-Bao

    2009-11-01

    Based on the field survey and the analysis of a large number of soil samples, the distribution of 137 Cs and its influencing factors were studied using 137 Cs tracer technology on typical karst sloping land. The results indicate that the distribution of 137 Cs in soil profile in karst areas show the similar characteristics as that in non-karst areas, fitted an exponential pattern in forest soils and a uniform pattern in cultivated soils. In the sinkhole points in karst areas, 137 Cs exists in deep soil layers and its specific activity vary from 1.7 to 3.3 Bq/kg in soil layers above 45cm, suggesting the existing soil around karst sinkhole is mainly formed by the accumulation of erosion materials. The 137 Cs specific activity in the soil from two rock cracks are 16.8 Bq/kg and 37.6 Bq/kg respectively, which are much higher than that in the soil around the rock, this phenomenon indicates that bare rock is an important influencing factor for 137 Cs spatial movement. With the increment of altitude, the 137 Cs area activity exhibits an irregular fluctuation and evident spatial heterogeneity. On the forest land, the 137 Cs area activities which range from 299.4 to 1 592.6 Bq/m2 are highly positively correlated with the slope gradient and positively correlated with the altitude; while on the cultivated land, the 137 Cs area activities which range from 115.8 to 1478.6 Bq/m2 are negatively correlated with the slope gradient but negatively correlated with the altitude. Topography, geomorphology and human disturbance intensity are the key factors influencing 137 Cs spatial distribution.

  6. Effects of radiocesium inventory on (137)Cs concentrations in river waters of Fukushima, Japan, under base-flow conditions.

    PubMed

    Ochiai, Shinya; Ueda, Shinji; Hasegawa, Hidenao; Kakiuchi, Hideki; Akata, Naofumi; Ohtsuka, Yoshihito; Hisamatsu, Shun'ichi

    2015-06-01

    To investigate the behavior of nuclear accident-derived (137)Cs in river water under base-flow conditions, concentrations of dissolved and particulate (137)Cs were measured at 16 sampling points in seven rivers of Fukushima Prefecture, Japan, in 2012 and 2013. The concentration of dissolved (137)Cs was significantly correlated with the mean (137)Cs inventory in the catchment area above each sampling point in both sampling years. These results suggest that the concentration of dissolved (137)Cs under base-flow conditions is primarily determined by the (137)Cs inventory of the catchment area above the sampling point. However, the concentration of particulate (137)Cs did not show a clear relationship with either the mean (137)Cs inventory or the dissolved (137)Cs concentration, thus indicating that particulate and dissolved forms do not effectively interact in rivers. To evaluate the contribution of the (137)Cs inventory within catchment areas, we analyzed relations between the (137)Cs concentration and the mean (137)Cs inventory over the area within certain flow path lengths that were traced along the river and slope above the sampling point. Coefficients of determination for dissolved (137)Cs concentrations were highest for the longest flow path, i.e., the whole catchment area, and lower for shorter flow paths. Coefficients of determination for particulate (137)Cs concentrations were only moderately high for the shortest flow path in 2012, whereas the values were quite low for all flow paths in 2013. These results suggest that dissolved (137)Cs can originate from a larger area of the catchment even under base-flow conditions; however, particulate (137)Cs did not show such behavior. The results also show that under base-flow conditions, dissolved and particulate (137)Cs behave independently during their transport from river catchments to the ocean.

  7. 137Cs vertical migration in a deciduous forest soil following the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Nakanishi, Takahiro; Matsunaga, Takeshi; Koarashi, Jun; Atarashi-Andoh, Mariko

    2014-02-01

    The large amount of (137)Cs deposited on the forest floor because of the Fukushima Dai-ichi Nuclear Power Plant accident represents a major potential long-term source for mobile (137)Cs. To investigate (137)Cs mobility in forest soils, we investigated the vertical migration of (137)Cs through seepage water, using a lysimetric method. The study was conducted in a deciduous forest soil over a period spanning 2 month to 2 y after the Fukushima nuclear accident. Our observations demonstrated that the major part of (137)Cs in the litter layer moved into the mineral soil within one year after the accident. On the other hand, the topsoil prevented migration of (137)Cs, and only 2% of (137)Cs in the leachate from litter and humus layer penetrated below a 10 cm depth. The annual migration below a 10 cm depth accounted for 0.1% of the total (137)Cs inventory. Therefore, the migration of (137)Cs by seepage water comprised only a very small part of the total (137)Cs inventory in the mineral soil, which was undetectable from the vertical distribution of (137)Cs in the soil profile. In the present and immediate future, most of the (137)Cs deposited on the forest floor will probably remain in the topsoil successively, although a small but certain amount of bioavailable (137)Cs exists in forest surface soil.

  8. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    SciTech Connect

    1995-10-01

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department`s mission as stated in that document. ``The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.``

  9. Computational modeling of 137Cs contaminant transfer associated with sediment transport in Abukuma River.

    PubMed

    Iwasaki, T; Nabi, M; Shimizu, Y; Kimura, I

    2015-01-01

    A numerical model capable of simulating the transfer of (137)Cs in rivers associated with transport of fine sediment is presented. The accident at Fukushima Dai-ichi Nuclear Power Plant (FDNPP) released radionuclides into the atmosphere, and after fallout several radionuclides in them, such as radiocesium ((134)Cs, (137)Cs) and radioiodine ((131)I) were adsorbed on surface soil particles around FDNPP and transported by surface water. To understand the transport and deposition of the radioactive contaminant along with surface soil particles and its flux to the ocean, we modeled the transport of the (137)Cs contaminant by computing the water flow and the associated washload and suspended load transport. We have developed a two-dimensional model to simulate the plane flow structure, sediment transport and associated (137)Cs contaminant transport in rivers by combining a shallow water flow model and an advection-diffusion equation for the transport of sediment. The proposed model has been applied to the lower reach of Abukuma River, which is the main river in the highly contaminated area around FDNPP. The numerical results indicate that most (137)Cs supplied from the upstream river reach with washload would directly reach to Pacific Ocean. In contrast, washload-oriented (137)Cs supplied from the upstream river basin has a limited role in the radioactive contamination in the river. The results also suggest that the proposed framework of computational model can be a potential tool for understanding the sediment-oriented (137)Cs behavior in rivers. PMID:24909793

  10. Computational modeling of 137Cs contaminant transfer associated with sediment transport in Abukuma River.

    PubMed

    Iwasaki, T; Nabi, M; Shimizu, Y; Kimura, I

    2015-01-01

    A numerical model capable of simulating the transfer of (137)Cs in rivers associated with transport of fine sediment is presented. The accident at Fukushima Dai-ichi Nuclear Power Plant (FDNPP) released radionuclides into the atmosphere, and after fallout several radionuclides in them, such as radiocesium ((134)Cs, (137)Cs) and radioiodine ((131)I) were adsorbed on surface soil particles around FDNPP and transported by surface water. To understand the transport and deposition of the radioactive contaminant along with surface soil particles and its flux to the ocean, we modeled the transport of the (137)Cs contaminant by computing the water flow and the associated washload and suspended load transport. We have developed a two-dimensional model to simulate the plane flow structure, sediment transport and associated (137)Cs contaminant transport in rivers by combining a shallow water flow model and an advection-diffusion equation for the transport of sediment. The proposed model has been applied to the lower reach of Abukuma River, which is the main river in the highly contaminated area around FDNPP. The numerical results indicate that most (137)Cs supplied from the upstream river reach with washload would directly reach to Pacific Ocean. In contrast, washload-oriented (137)Cs supplied from the upstream river basin has a limited role in the radioactive contamination in the river. The results also suggest that the proposed framework of computational model can be a potential tool for understanding the sediment-oriented (137)Cs behavior in rivers.

  11. 239+240Pu, 90Sr and 137Cs inventories in surface soils of Vietnam.

    PubMed

    Quang, N H; Long, N Q; Lieu, D B; Mai, T T; Ha, N T; Nhan, D D; Hien, P D

    2004-01-01

    Fallout 239+240Pu, 238Pu, 90Sr and 137Cs inventories in surface soils were measured for 20 locations in northern Vietnam yielding the mean values (+/- standard error) of 26.5+/-3.8 Bq m(-2) for 239+240Pu, 1048+/-143 Bq m(-2) for 137Cs and 212+/-28 Bq m(-2) for 90Sr. The concentrations of 137Cs and plutonium isotopes strongly correlate with each other resulting in a stable 239+240Pu/137Cs inventory ratio of 0.025+/-0.002. Among soil parameters, organic matter and fulvic acids strongly correlate with caesium and plutonium isotopes, especially in the 0-10 cm layer. 137Cs and 239+240Pu are distributed rather similarly over the 0-10 cm and 10-20 cm layers. At locations with high contents of sand (82-93%) along the South China Sea coast, the downward percolation by rainwater results in a higher accumulation of 239+240Pu and 137Cs in the 10-20 cm layer. The mean 137Cs/ 90Sr inventory ratio is 9.3+/-2.2, and the correlation is weak between these isotopes.

  12. Evaluation of radioactive exposure from 137Cs in contaminated areas of Northern Ukraine.

    PubMed

    Handl, J; Beltz, D; Botsch, W; Harb, S; Jakob, D; Michel, R; Romantschuk, L D

    2003-04-01

    The paper gives averages of 137Cs deposition densities in soils from three areas in Northern Ukraine measured 12 to 15 y following the Chernobyl accident: in an area near Narodici (75 km west of the Chernobyl nuclear power plant in the so-called zone II) heavily contaminated by the Chernobyl fall-out and in areas around Korosten and Zhitomir showing contamination levels to be much lower. The three areas exhibited very different 137Cs deposition densities of 2.2 MBq m(-2), 400 kBq m(-2), and 5 kBq m(-2), respectively. During a 1-y observation, measurements of the 137Cs transfer in the food chain to humans and 137Cs whole body contents dependent on the 137Cs daily intake were carried out under realistic conditions of the rural inhabitants who lived in settlements within zone II. Detailed investigations of components of the daily diet showed that the high 137Cs contamination levels found in soils of zone II do not affect in any way low 137Cs concentrations of all important agricultural products harvested and consumed by villagers. With regard to consumption habits of the population of zone II, mushrooms and wild berries were found to contribute more than 95% of the 137Cs daily intake to the 137Cs whole body content of about 12 kBq (with maximum values up to 760 kBq) measured in a group of inhabitants of zone II during a period from July 1998 to July 1999. The median of the annual dose of these inhabitants from external and internal exposures was 1.2 mSv y(-1) with a geometric standard deviation of 2.6. Excluding extreme habits, the geometric mean of the total exposure was 1.0 mSv y(-1) with a geometric standard deviation of 1.3. PMID:12705449

  13. Long-term transport and dispersion of 137Cs released into ocean off Fukushima nuclear accident

    NASA Astrophysics Data System (ADS)

    Zhao, Chang; Qiao, Fangli; Wang, Guansuo; Xia, Changshui; Jung, KyungTae

    2014-05-01

    In the following days after the Fukushima nuclear accident which happened in 11th March 2011, significant amounts of radioactive materials (131I, 134Cs and 137Cs) had been leaking into the terrestrial and marine environments. The radionuclides model was used to study the distribution of the 137Cs in the Pacific and the Indian Ocean released from the Fukushima accident. The simulation on the distribution of 137Cs agrees well with the the observed profiles in the 9th November 2011, which proved the validaty of the model. In the first year of our model run, the 137Cs is carried eastward by the Kuroshio and its extension, spreading southward and northword meanwhile. Four or five years after the accident, the 137Cs reaches the US coast with the surface waters of the Pacific Ocean; its concentration is no higher than 3 Bq/m3. Ten years after the accident, all the North Pacific Ocean is labeled with the 137Cs from the Fukushima. The concentration is less than 1 Bq/m3 at that time. Thirty years after the accident, the concentration of 137Cs in both the Pacific and the Indian Ocean is below 0.1 Bq/m3. Since the spreading path of 137Cs from the Fukushima nuclear accident is just the migration route of the Pacific tuna, a kind of fish inhabit the western and eastern North Pacific, it may cause radioactive contamination to the fish. In the offshore seas of China, the 137Cs from Fukushima nuclear accident is very low (<0.2 Bq/m3) .

  14. Evaluation of radioactive exposure from 137Cs in contaminated areas of Northern Ukraine.

    PubMed

    Handl, J; Beltz, D; Botsch, W; Harb, S; Jakob, D; Michel, R; Romantschuk, L D

    2003-04-01

    The paper gives averages of 137Cs deposition densities in soils from three areas in Northern Ukraine measured 12 to 15 y following the Chernobyl accident: in an area near Narodici (75 km west of the Chernobyl nuclear power plant in the so-called zone II) heavily contaminated by the Chernobyl fall-out and in areas around Korosten and Zhitomir showing contamination levels to be much lower. The three areas exhibited very different 137Cs deposition densities of 2.2 MBq m(-2), 400 kBq m(-2), and 5 kBq m(-2), respectively. During a 1-y observation, measurements of the 137Cs transfer in the food chain to humans and 137Cs whole body contents dependent on the 137Cs daily intake were carried out under realistic conditions of the rural inhabitants who lived in settlements within zone II. Detailed investigations of components of the daily diet showed that the high 137Cs contamination levels found in soils of zone II do not affect in any way low 137Cs concentrations of all important agricultural products harvested and consumed by villagers. With regard to consumption habits of the population of zone II, mushrooms and wild berries were found to contribute more than 95% of the 137Cs daily intake to the 137Cs whole body content of about 12 kBq (with maximum values up to 760 kBq) measured in a group of inhabitants of zone II during a period from July 1998 to July 1999. The median of the annual dose of these inhabitants from external and internal exposures was 1.2 mSv y(-1) with a geometric standard deviation of 2.6. Excluding extreme habits, the geometric mean of the total exposure was 1.0 mSv y(-1) with a geometric standard deviation of 1.3.

  15. Behavior of 131I and 137Cs in environments released from the Fukushima nuclear disaster

    NASA Astrophysics Data System (ADS)

    Ohta, T.; Mahara, Y.; Kubota, T.; Igarashi, T.

    2011-12-01

    The devastating tsunami that caused by the great earthquake (M = 9.0) off the coast of northeastern Honshu on 11 March 2011 destroyed large coastal areas of Tohoku and north Kanto, Japan. Radionuclides, including 131I, 134Cs, and 137Cs, were released into the atmosphere from the Fukushima Daiichi plants. Concentration of levels of 131I, 134Cs, and 137Cs in Ibaraki Prefecture, Japan, released from the Fukushima Daiichi plant were investigated in the soil and precipitation. The concentrations of 131I and 137Cs in the soil from the surface to 1 cm depth in Ibaraki Prefecture were 9360-13,400 Bq/kg and 720-3250 Bq/kg, respectively. The concentration of 137Cs at this soil observation site originating from the Fukushima plant was 8.4 to 21 times that found locally after the Nagasaki atomic bomb explosion. Most of the 134Cs and 137Cs from rainwater were trapped by the surface soil and sand to a depth of 1 cm, whereas only about 30% of the 131I was collected by the surface soil, suggesting that 131I would move deeper than 137Cs and 134Cs. The 131I in the rainwater was in the anion exchangeable form, and all of it could be collected by anion exchangeable mechanisms, whereas 30% of the 131I that had passed through the soil could not be trapped by the anion exchange resin, suggesting that the chemical form of this 30% was in a changeable, organic-bound form. The 131I, 134Cs, and 137Cs that were absorbed on soil were difficult to be dissolved into water. As the half-life of 131I is short and 137Cs is strongly adsorbed on the surface soil and sand, these radionuclides would be unlikely to reach the groundwater before completely decaying; contamination of groundwater with 131I and 137Cs supplied from rainwater to the surface soil is therefore exceedingly unlikely. As the 137Cs is likely to migrate only 0.6 cm in 10 years, people living in the Fukushima and Kanto areas will be exposed to radiation from 137Cs in the surface soil and sand. For protection, surface soils and sands

  16. 210Pb method for estimating the rate of carbonate sand sedimentation

    USGS Publications Warehouse

    Holmes, Charles W.

    1981-01-01

    The plot of 210Pb activity against depth in carbonate sands on the Virgin Island Bank is a negative asymmetric hyperbolic curve. As depth increases, an initial rapid decrease in 210Pb activity caused by the decay of unsupported 210Pb and 226Ra is followed by increasing activity as a result of 210Pb achieving equilibrium with in growing 230Th. As this curve is time dependent, an estimate of the relative ages in carbonate sequences and the rates of net carbonate accumulation can be made. The ease of 210Pb activity determinations makes this procedure an attractive method in obtaining carbonate sand accumulation rates.

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

    PubMed

    Zotina, T A; Trofimova, E A; Dementyev, D V; Bolsunovsky, A Ya

    2016-05-01

    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 7.0 Bq/kg of fresh weight. The maximum content of the radionuclide has been found in juveniles. The content of (137)Cs in pike muscles and body decreased considerably with age. The high content of (137)Cs in the muscles of juveniles is probably a consequence of their higher intensity of feeding as compared to older individuals, which is due to the intense growth of juveniles. PMID:27411826

  18. Relations of fine-root morphology on (137)Cs uptake by fourteen Brassica species.

    PubMed

    Aung, Han Phyo; Aye, Yi Swe; Mensah, Akwasi Dwira; Omari, Richard Ansong; Djedidi, Salem; Oikawa, Yosei; Ohkama-Ohtsu, Naoko; Yokoyama, Tadashi; Bellingrath-Kimura, Sonoko Dorothea

    2015-12-01

    Fourteen Brassica species consisting of seven leafy vegetables and seven root vegetables were examined for (137)Cs uptake differences in relation to their fine-root morphological characters. A pot experiment was conducted from November 2014 to February 2015 in a Phytroton using a contaminated soil of Fukushima prefecture. Leafy vegetables showed bigger root diameters, larger root surface area and larger root volume. Consequently, leafy vegetables had higher (137)Cs uptake compared to root vegetables. Among the three fine-root parameters, only root surface area was observed as a significant contributing factor to higher (137)Cs uptake in terms of transfer factor (TF, dry weight basis). Kakina exhibited higher (137)Cs TF value (0.20) followed by Chinese cabbage (0.18) and mizuna (0.17). Lower TF values were observed in turnip (0.059), rutabaga (Kitanoshou) (0.062) and radish (Ha daikon) (0.064). PMID:26355648

  19. Relations of fine-root morphology on (137)Cs uptake by fourteen Brassica species.

    PubMed

    Aung, Han Phyo; Aye, Yi Swe; Mensah, Akwasi Dwira; Omari, Richard Ansong; Djedidi, Salem; Oikawa, Yosei; Ohkama-Ohtsu, Naoko; Yokoyama, Tadashi; Bellingrath-Kimura, Sonoko Dorothea

    2015-12-01

    Fourteen Brassica species consisting of seven leafy vegetables and seven root vegetables were examined for (137)Cs uptake differences in relation to their fine-root morphological characters. A pot experiment was conducted from November 2014 to February 2015 in a Phytroton using a contaminated soil of Fukushima prefecture. Leafy vegetables showed bigger root diameters, larger root surface area and larger root volume. Consequently, leafy vegetables had higher (137)Cs uptake compared to root vegetables. Among the three fine-root parameters, only root surface area was observed as a significant contributing factor to higher (137)Cs uptake in terms of transfer factor (TF, dry weight basis). Kakina exhibited higher (137)Cs TF value (0.20) followed by Chinese cabbage (0.18) and mizuna (0.17). Lower TF values were observed in turnip (0.059), rutabaga (Kitanoshou) (0.062) and radish (Ha daikon) (0.064).

  20. A comparison of {sup 137}Cs radioactivity in localized evergreen and deciduous plant species

    SciTech Connect

    Rangel, R.C.

    1996-05-01

    A vegetation study at the Comanche Peak Steam Electric Station (CPSES) near Glen Rose, Texas was conducted in 1991 and 1992. The CPSES is a commercial nuclear power plant owned and operated by Texas Utilities Electric of Dallas, Texas. The US Nuclear Regulatory Commission (USNRC) requires the CPSES to routinely sample broadleaf vegetation in place of milk samples. Few commercial dairies exist in the vicinity. Broadleaf tree species are scarce because the climate and local limestone geology have produced a dry rolling hill topography. An evergreen juniper is the dominant tree species. Few broadleaves during the winter season have hindered year-round sampling. This study compares the environmental {sup 137}Cs concentrations between broadleaf and evergreen foliage at CPSES. Soil {sup 137}Cs concentrations from each vegetation location were also compared to the foliage {sup 137}Cs concentrations. The study`s objective was to determine if the deciduous and evergreen vegetation {sup 137}Cs concentrations are statistically the same.

  1. Long-term retention of (137)Cs in three forest soil types with different soil properties.

    PubMed

    Suchara, Ivan; Sucharová, Julie; Holá, Marie; Pilátová, Helena; Rulík, Petr

    2016-07-01

    Current (137)Cs activity concentrations were studied at three localities in individual soil horizons of Stagnosol, Arenic Podzol and Haplic Cambisol soil units in soil blocks with dimensions of 20 × 20 × 40 cm situated below pine canopies (n = 3) and spruce canopies (n = 3), and below small canopy gaps, at least 15 × 15 m in area (n = 3 + 3), which have probably endured since 1986. The main zone of (137)Cs accumulation in all the localities was found to be in the organic horizons (H and F). No significant transport and accumulation of (137)Cs into illuvial soil horizons (Bm, Bs or Bhs, Bv and Bv/IIC) was found. The estimated current total (137)Cs activity concentrations in the soil blocks 40 cm in depth were only slightly higher below the coniferous canopy than they were below nearby canopy gaps. The inventory of (137)Cs in the soils was found to be in accordance with the estimated (137)Cs inputs from the Chernobyl fallout and from global fallout. The low amounts of (137)Cs found accumulated in the aboveground biomass (mosses, grasses, needles) did not substantially bias the studied radiocaesium balance in the soils. The vertical migration rate of (137)Cs in soils (cm/year) had a tendency to be higher below canopies than below canopy gaps and below pine canopies than below spruce canopies. We expected the current (137)Cs activity concentrations in the individual soil horizons to be related to the studied soil parameters: pH (H2O), pH (CaCl2), content of organic matter and mineral portion and portion of humic and fulvic acid contents (Q4/6). However, this was not confirmed. Similarly, we observed a weak tendency toward higher (137)Cs activity in soils below the canopy than in soils below canopy gaps. The available gaps used in our study may have been too small, and they may have been affected by an accumulation of litter and humus containing (137)Cs from the surrounding plots situated below neighbouring canopies. PMID:27085039

  2. Long-term retention of (137)Cs in three forest soil types with different soil properties.

    PubMed

    Suchara, Ivan; Sucharová, Julie; Holá, Marie; Pilátová, Helena; Rulík, Petr

    2016-07-01

    Current (137)Cs activity concentrations were studied at three localities in individual soil horizons of Stagnosol, Arenic Podzol and Haplic Cambisol soil units in soil blocks with dimensions of 20 × 20 × 40 cm situated below pine canopies (n = 3) and spruce canopies (n = 3), and below small canopy gaps, at least 15 × 15 m in area (n = 3 + 3), which have probably endured since 1986. The main zone of (137)Cs accumulation in all the localities was found to be in the organic horizons (H and F). No significant transport and accumulation of (137)Cs into illuvial soil horizons (Bm, Bs or Bhs, Bv and Bv/IIC) was found. The estimated current total (137)Cs activity concentrations in the soil blocks 40 cm in depth were only slightly higher below the coniferous canopy than they were below nearby canopy gaps. The inventory of (137)Cs in the soils was found to be in accordance with the estimated (137)Cs inputs from the Chernobyl fallout and from global fallout. The low amounts of (137)Cs found accumulated in the aboveground biomass (mosses, grasses, needles) did not substantially bias the studied radiocaesium balance in the soils. The vertical migration rate of (137)Cs in soils (cm/year) had a tendency to be higher below canopies than below canopy gaps and below pine canopies than below spruce canopies. We expected the current (137)Cs activity concentrations in the individual soil horizons to be related to the studied soil parameters: pH (H2O), pH (CaCl2), content of organic matter and mineral portion and portion of humic and fulvic acid contents (Q4/6). However, this was not confirmed. Similarly, we observed a weak tendency toward higher (137)Cs activity in soils below the canopy than in soils below canopy gaps. The available gaps used in our study may have been too small, and they may have been affected by an accumulation of litter and humus containing (137)Cs from the surrounding plots situated below neighbouring canopies.

  3. [90Sr and 137Cs in higher aquatic plants of the Chernobyl nuclear plant exlusion zone

    PubMed

    Gudkov, D I; Derevets, V V; Kuz'menko, M I; Nazarov, A B

    2001-01-01

    The content of radionuclides 90Sr and 137Cs in higher aquatic plants of water objects within Chernobyl NPP exclusion zone has been analysed. Biodiversity of phytocenose was studied and species-indicators of radioactive contamination were revealed. The seasonal dynamics of radionuclide content in macrophytes was studied and the role of main aquatic plant clumps in processes of 137Cs and 90Sr distribution in abiotic component of biohydrocenose was demonstrated.

  4. A measurement routine to determine 137Cs activities at steep mountain slopes

    NASA Astrophysics Data System (ADS)

    Schaub, Monika; Konz, Nadine; Meusburger, Katrin; Alewell, Chrstine

    2010-05-01

    Caesium-137 (137Cs) is a common tracer for soil erosion. So far, in-situ measurements in steep alpine environments have not often been done. Most studies have been carried out in arable lands and with Ge detectors. However, the NaI detector system is a good priced, easy to handle field instrument. A comparison of laboratory measurements with GeLi detector and in-situ measurements with NaI detector of 137Cs gamma soil radiation has been done in an alpine catchment (Urseren Valley, Swizerland). The aim of this study was to calibrate the in-situ NaI detector system for application at steep alpine slopes. Replicate samples from an altitudinal transect through the Urseren Valley were measured ex situ in the laboratory with a GeLi detector, and compared to in situ NaI detector measurements. Ex situ soil samples showed a big variability in 137Cs activities at a meter-scale. This large, small scale heterogeneity determined with the GeLi detector is smoothed out by uncollimated in-situ measurements with the NaI detector, which provide integrated estimates of 137Cs within the field of view of each measurement (3.1 m2). There was no dependency of 137Cs on pH, clay content and carbon content. However, a close relationship was determined between 137Cs and soil moisture. Thus, in-situ data must be corrected for soil moisture. Close correlation (R2 = 0.86) was found for 137Cs activities (in Bq kg-1) estimated with both, in-situ (NaI detector) and laboratory (GeLi detector) methods which proves the validity of the in-situ measurements with the NaI detector system. This paper describes the calibration of the NaI detector system for field application under elevated 137Cs activities originating from Chernobyl fallout.

  5. Plutonium and 137Cs in surface water of the South Pacific Ocean.

    PubMed

    Hirose, K; Aoyama, M; Fukasawa, M; Kim, C S; Komura, K; Povinec, P P; Sanchez-Cabeza, J A

    2007-08-01

    The present plutonium and 137Cs concentrations in South Pacific Ocean surface waters were determined. The water samples were collected in the South Pacific mid-latitude region (32.5 degrees S) during the BEAGLE expedition conducted in 2003-04 by JAMSTEC. 239,240Pu concentrations in surface seawater of the South Pacific were in the range of 0.5 to 4.1 mBq m(-3), whereas 137Cs concentrations ranged from 0.07 to 1.7 Bq m(-3). The observed 239,240Pu and 137Cs concentrations in the South Pacific were almost of the same level as those in the North Pacific subtropical gyre. The surface 239,240Pu in the South Pacific subtropical gyre showed larger spatial variations than 137Cs, as it may be affected by physical and biogeochemical processes. The 239,240Pu/137Cs activity ratios, which reflect biogeochemical processes in seawater, were generally smaller than that observed in global fallout, except for the most eastern station. The 239,240Pu/137Cs ratios in the South Pacific tend to be higher than that in the North Pacific. The relationships between anthropogenic radionuclides and oceanographic parameters such as salinity and nutrients were examined. The 137Cs concentrations in the western South Pacific (the Tasman Sea) and the eastern South Pacific were negatively correlated with the phosphate concentration, whereas there is no correlation between the 137Cs and nutrients concentrations in the South Pacific subtropical gyre. The mutual relationships between anthropogenic radionuclides and oceanographic parameters are important for better understanding of transport processes of anthropogenic radionuclides and their fate in the South Pacific. PMID:17459459

  6. Plutonium and 137Cs in surface water of the South Pacific Ocean.

    PubMed

    Hirose, K; Aoyama, M; Fukasawa, M; Kim, C S; Komura, K; Povinec, P P; Sanchez-Cabeza, J A

    2007-08-01

    The present plutonium and 137Cs concentrations in South Pacific Ocean surface waters were determined. The water samples were collected in the South Pacific mid-latitude region (32.5 degrees S) during the BEAGLE expedition conducted in 2003-04 by JAMSTEC. 239,240Pu concentrations in surface seawater of the South Pacific were in the range of 0.5 to 4.1 mBq m(-3), whereas 137Cs concentrations ranged from 0.07 to 1.7 Bq m(-3). The observed 239,240Pu and 137Cs concentrations in the South Pacific were almost of the same level as those in the North Pacific subtropical gyre. The surface 239,240Pu in the South Pacific subtropical gyre showed larger spatial variations than 137Cs, as it may be affected by physical and biogeochemical processes. The 239,240Pu/137Cs activity ratios, which reflect biogeochemical processes in seawater, were generally smaller than that observed in global fallout, except for the most eastern station. The 239,240Pu/137Cs ratios in the South Pacific tend to be higher than that in the North Pacific. The relationships between anthropogenic radionuclides and oceanographic parameters such as salinity and nutrients were examined. The 137Cs concentrations in the western South Pacific (the Tasman Sea) and the eastern South Pacific were negatively correlated with the phosphate concentration, whereas there is no correlation between the 137Cs and nutrients concentrations in the South Pacific subtropical gyre. The mutual relationships between anthropogenic radionuclides and oceanographic parameters are important for better understanding of transport processes of anthropogenic radionuclides and their fate in the South Pacific.

  7. Factors controlling the spatiotemporal variation of (137)Cs in seabed sediment off the Fukushima coast: implications from numerical simulations.

    PubMed

    Misumi, Kazuhiro; Tsumune, Daisuke; Tsubono, Takaki; Tateda, Yutaka; Aoyama, Michio; Kobayashi, Takuya; Hirose, Katsumi

    2014-10-01

    We used numerical simulations to investigate major controls on spatiotemporal variations of (137)Cs activities in seabed sediments off the Fukushima coast during the first year after the Fukushima Daiichi Nuclear Power Plant accident. The numerical model we used includes (137)Cs transfer between bottom water and sediment by adsorption and desorption, and radioactive decay. The model successfully reproduced major features of the observed spatiotemporal variations of (137)Cs activities in sediments. The spatial pattern of (137)Cs in sediments, which mainly reflected the history of (137)Cs activities in bottom water overlying the sediments and the sediment particle size distribution, became established during the first several months after the accident. The simulated temporal persistence of the (137)Cs activity in the sediments was due to adsorption of (137)Cs onto the sediment mineral fraction having a long desorption timescale of (137)Cs. The simulated total (137)Cs inventory in sediments integrated over the offshore area, where most of the monitoring stations were located, was on the order of 10(13) Bq; this value is consistent with a previous estimate based on observed data. Taking into account (137)Cs activities in sediments in both the coastal area and in the vicinity of the power plant, the simulated total inventory of (137)Cs in sediments off the Fukushima coast increased to a value on the order of 10(14) Bq.

  8. (137)Cs trapped by biomass within 20 km of the Fukushima Daiichi Nuclear Power Plant.

    PubMed

    Koizumi, Akio; Niisoe, Tamon; Harada, Kouji H; Fujii, Yukiko; Adachi, Ayumu; Hitomi, Toshiaki; Ishikawa, Hirohiko

    2013-09-01

    Analysis of (137)Cs trapped in biomass in highly contaminated zones is crucial in predicting the long-term fate of (137)Cs following the explosion at the Fukushima Daiichi Nuclear Power Plant. We surveyed forest 20-50 km from the plant in July and September 2011 to evaluate (137)Cs trapped in biomass within 20 km of the plant. We determined the ambient dose rate and collected forest soils and twigs at 150 sampling points. Removability from the canopy was evaluated by washing leaves and branches with water and organic solvents. The biomass of the forest canopy was then calculated. (137)Cs fallout was simulated with an atmospheric transport model. The modeled dose rate agreed with observations (n = 24) (r = 0.62; p < 0.01). Washing experiments demonstrated that unremovable portions accounted for 53.9 ± 6.4% of (137)Cs trapped by deciduous canopy (n = 4) and 59.3 ± 13.8% of (137)Cs trapped by evergreen canopy (n = 10). In total, it was estimated that 74.5 × 10(12) Bq was trapped by canopy in the forest within the no-go zone, with 44.2 × 10(12) Bq allocated to unremovable portions, and that 0.86% of the total release was trapped in biomass as of September 2011. PMID:23889208

  9. Deposition of atmospheric (137)Cs in Japan associated with the Asian dust event of March 2002.

    PubMed

    Fujiwara, Hideshi; Fukuyama, Taijiro; Shirato, Yasuhito; Ohkuro, Toshiya; Taniyama, Ichiro; Zhang, Tong-Hui

    2007-10-01

    Considerable deposition of (137)Cs was observed in the northwestern coastal area of Japan in March 2002. Since there were no nuclear explosions or serious nuclear accidents in the early 2000s, transport of previously contaminated dust appears to be the only plausible explanation for this event. In March 2002, there was a massive sandstorm on the East Asian continent, and the dust raised by the storm was transported across the sea to Japan. This dust originated in Mongolia and northeastern China, in an area distant from the Chinese nuclear test site at Lop Nor or any other known possible sources of (137)Cs. Our radioactivity measurements showed (137)Cs enrichment in the surface layer of grassland soils in the area of the sandstorm, which we attributed to accumulation as a result of past nuclear testing. We suggest that the grassland is a potential source of (137)Cs-bearing soil particles. Since the late 1990s, this area has experienced drought conditions, resulting in a considerable reduction of vegetation cover. We attribute the prodigious release of (137)Cs-bearing soil particles into the atmosphere during the sandstorm and the subsequent deposition of (137)Cs in Japan to this change.

  10. 137Cs distribution among annual rings of different tree species contaminated after the Chernobyl accident.

    PubMed

    Soukhova, N V; Fesenko, S V; Klein, D; Spiridonov, S I; Sanzharova, N I; Badot, P M

    2003-01-01

    The distributions of 137Cs among annual rings of Pinus sylvestris and Betula pendula at four experimental sites located in the most contaminated areas in the Russian territory after the Chernobyl accident in 1986 were studied. Trees of different ages were sampled from four forest sites with different tree compositions and soil properties. The data analysis shows that 137Cs is very mobile in wood and the 1986 rings do not show the highest contamination. The difference between pine and birch in the pattern of radial 137Cs distribution can be satisfactorily explained by the difference in radial ray composition. 137Cs radial distribution in the wood can be described as the sum of two exponential functions for both species. The function parameters are height, age and species dependent. The distribution of 137Cs in birch wood reveals much more pronounced dependence on site characteristics and/or the age of trees than pines. The data obtained can be used to assess 137Cs content in wood. PMID:12683726

  11. Deposition of atmospheric (137)Cs in Japan associated with the Asian dust event of March 2002.

    PubMed

    Fujiwara, Hideshi; Fukuyama, Taijiro; Shirato, Yasuhito; Ohkuro, Toshiya; Taniyama, Ichiro; Zhang, Tong-Hui

    2007-10-01

    Considerable deposition of (137)Cs was observed in the northwestern coastal area of Japan in March 2002. Since there were no nuclear explosions or serious nuclear accidents in the early 2000s, transport of previously contaminated dust appears to be the only plausible explanation for this event. In March 2002, there was a massive sandstorm on the East Asian continent, and the dust raised by the storm was transported across the sea to Japan. This dust originated in Mongolia and northeastern China, in an area distant from the Chinese nuclear test site at Lop Nor or any other known possible sources of (137)Cs. Our radioactivity measurements showed (137)Cs enrichment in the surface layer of grassland soils in the area of the sandstorm, which we attributed to accumulation as a result of past nuclear testing. We suggest that the grassland is a potential source of (137)Cs-bearing soil particles. Since the late 1990s, this area has experienced drought conditions, resulting in a considerable reduction of vegetation cover. We attribute the prodigious release of (137)Cs-bearing soil particles into the atmosphere during the sandstorm and the subsequent deposition of (137)Cs in Japan to this change. PMID:17604085

  12. The (137)Cs accumulation by forest-derived products in the Gomel region.

    PubMed

    Bulko, N I; Shabaleva, M A; Kozlov, A K; Tolkacheva, N V; Mashkov, I A

    2014-01-01

    This paper reports basic features of the (137)Cs uptake by forest-derived products in the Gomel region. Even with the soil contamination density of 37 kBq m(-2) the radionuclide contents in 20-30% of mushrooms and berries were found to be higher than the admissible levels. The (137)Cs contamination density of soil, site type and meteorological parameters were observed as the major factors which govern the radiocaesium uptake by mushrooms and berries. The (137)Cs contents in forest-derived products were found to increase directly with the soil contamination density. Bilberries (Vaccinium myrtillus) growing on different site types differed significantly in the (137)Cs content. It was also determined that statistically significant differences in the (137)Cs radioactivity of forest foods growing on different natural sites were governed by the factor designated in the current study by "territorial". The differences are to be accounted for both by forms of the Chernobyl fallout and by the natural and climatic conditions determining variations in the availability of radionuclides in the soil. In dry years the (137)Cs concentrations in some mushroom species were higher than in normal years.

  13. Sediment and (137)Cs behaviors in the Ogaki Dam Reservoir during a heavy rainfall event.

    PubMed

    Kurikami, Hiroshi; Kitamura, Akihiro; Yokuda, Satoru Thomas; Onishi, Yasuo

    2014-11-01

    We performed a simulation of sediment and (137)Cs behaviors in the Ogaki Dam Reservoir, one of the main irrigation reservoirs in the Fukushima prefecture, Japan, during a heavy rainfall event occurred in 2013. The one-dimensional river and reservoir simulation scheme TODAM, Time-dependent One-dimensional Degradation and Migration, was applied for calculating the time dependent migration of sediment and (137)Cs in dissolved and sediment-sorbed forms in the reservoir. Continuous observational data achieved in the upper rivers were used as the input boundary conditions for the simulation. The simulation results were compared with the continuous data achieved in the lower river and we confirmed the predicted values of sediment and (137)Cs in sediment-sorbed form at the exit of reservoir satisfactorily reproduced the observational data. We also performed sediment and (137)Cs behavioral simulation by changing the water level of the reservoir, because such a dam operation could control the quantities of sediment and (137)Cs discharge from and/or deposition in the reservoir. The simulation clarified that the reservoir played an important role to delay and buffer the movement of radioactive cesium in heavy rainfall events and the buffer effect of the reservoir depended on particle sizes of suspended sediment and the water level. It was also understood that silt deposition was the main source of the bed contamination (except for the initial fallout impact), while clay was the main carrier of (137)Cs to the lower river at a later stage of rainfall events.

  14. (137)Cs trapped by biomass within 20 km of the Fukushima Daiichi Nuclear Power Plant.

    PubMed

    Koizumi, Akio; Niisoe, Tamon; Harada, Kouji H; Fujii, Yukiko; Adachi, Ayumu; Hitomi, Toshiaki; Ishikawa, Hirohiko

    2013-09-01

    Analysis of (137)Cs trapped in biomass in highly contaminated zones is crucial in predicting the long-term fate of (137)Cs following the explosion at the Fukushima Daiichi Nuclear Power Plant. We surveyed forest 20-50 km from the plant in July and September 2011 to evaluate (137)Cs trapped in biomass within 20 km of the plant. We determined the ambient dose rate and collected forest soils and twigs at 150 sampling points. Removability from the canopy was evaluated by washing leaves and branches with water and organic solvents. The biomass of the forest canopy was then calculated. (137)Cs fallout was simulated with an atmospheric transport model. The modeled dose rate agreed with observations (n = 24) (r = 0.62; p < 0.01). Washing experiments demonstrated that unremovable portions accounted for 53.9 ± 6.4% of (137)Cs trapped by deciduous canopy (n = 4) and 59.3 ± 13.8% of (137)Cs trapped by evergreen canopy (n = 10). In total, it was estimated that 74.5 × 10(12) Bq was trapped by canopy in the forest within the no-go zone, with 44.2 × 10(12) Bq allocated to unremovable portions, and that 0.86% of the total release was trapped in biomass as of September 2011.

  15. Biological effects of {sup 137}CsCl injected in beagle dogs

    SciTech Connect

    Nikula, K.J.; Muggenburg, B.A.; Griffith, W.C.

    1995-06-01

    The toxicity of intravenously administered {sup 137}CsCl in the beagle dog was investigated as part of a program to evaluate the biological effects of internally deposited fission-product radionuclides. The intravenous route of exposure was chosen for simplicity and accuracy because it was known that after intravenous injection, inhalation or ingestion, internally deposited {sup 137}CsCl is rapidly absorbed and distributed throughout the body, exposing the whole body to {beta}-particle and {gamma} radiations. Fifty-four dogs were injected intravenously with {sup 137}Cs to provide one group of six dogs with mean initial body burdens of 141 MBq {sup 137}Cs/kg body mass and four groups of 12 dogs each with mean initial body burdens of 104, 72, 52 and 36 MBq {sup 137}Cs/kg. Twelve dogs were injected with isotonic saline as study controls. Because the number of study controls dogs was small, data from an additional 49 control dogs from other studies at the Inhalation Toxicology Research Institute that were performed over a similar span of years were also used. There was a significant, dose-dependent decrease in survival of the {sup 137}Cs-injected dogs. Eleven {sup 137}Cs-injected dogs, including all six in the highest initial body burden group, died within 81 days after injection, primarily due to hematopoietic cell damage resulting in severe pancytopenia. An additional 25 dogs had transient hematological dyscrasia but survived for long times. All {sup 137}Cs-injected male dogs had marked damage to the germinal epithelium of the testicular seminiferous tubules with azoospermia in the long-term survivors. benign and malignant neoplasms occurred in a variety of organs in {sup 137}Cs-injected dogs, rather than in a single target organ. When individual organs were considered, the incidence of malignant neoplasms was increased in the liver and in the nasal cavity and paranasal sinuses of the {sup 137}Cs-injected dogs. 34 refs., 6 figs., 6 tabs.

  16. Assessment of 137Cs and 90Sr Fluxes in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Matishov, Gennady; Usiagina, Irina; Kasatkina, Nadezhda; Ilin, Gennadii

    2014-05-01

    On the basis of published and own data the annual balance of radionuclide income/outcome was assessed for 137Cs and 90Sr in the Barents Sea for the period from 1950s to the presnt. The scheme of the isotope balance calculation in the Barents Sea included the following processes:atmospheric fallout; river run-off; liquid radioactive wastes releases, income from the Norwegian and the White Seas; outflow to the adjacent areas through the Novaya Zemlya straits and the transects Svalbard-Franz Josef Land and Franz Josef Land-Novaya Zemlya; radioactive decay. According to the multiyear dynamics, the inflow of 137Cs and 90Sr to the Barents Sea was significantly preconditioned by currents from the Norwegian Sea. Three peaks of 137Cs and 90Sr isotope concentrations were registered for the surface waters on the western border of the Barents Sea. The first one was observed in the mid-1960s and was conditioned by testing of nuclear weapons. The increase of isotope concentrations in 1975 and 1980 was preconditioned by the discharge of atomic waste by the Sellafield nuclear reprocessing plant. Nowadays, after the sewage disposal plant was built, the annual discharge of nuclear waste from Sellafield plant is low. The Norwegian Sea was a major source of 137Cs and 90Sr isotope income into the Barents Sea for the period of 1960-2014. Currently, the transborder transfer of 90Sr and 137Cs from the Norwegian Sea into the Barents Sea constitutes about 99% of income for each element. Atmospheric precipitation had a major impact in the 1950-1960s after the testing of the nuclear weapons, and in 1986 after the accident at Chernobyl Nuclear Power Station. In 1963, the atmospheric precipitation of 137Cs reached 1050 TBq; and that of 90Sr, 630 TBq. In 1986, a significant amount of 137Cs inflow (up to 1010 TBq/year) was registered. The 137Cs isotope income exceeded the 90Sr income in the 1960s-1980s, and equal amounts penetrated into the Barents Sea from the Norwegian Sea in the 1990s. Before

  17. [137Cs profile distribution character and its implication for soil erosion on Karst slopes of northwest Guangxi].

    PubMed

    Feng, Teng; Chen, Hong-song; Zhang, Wei; Nie, Yun-peng; Wang, Ke-lin

    2011-03-01

    This paper studied the profile distribution characters of 137Cs and soil organic carbon (SOC) on the Karst slopes and in the fissures in typical peak-cluster depression in Northwest Guangxi, aimed to approach the applicability of 137Cs method on Karst slopes and the implication of 37Cs for the characteristics of slope soil erosion. In all test profiles, there was a significant correlation between 137Cs and SOC, indicating that both of them might have the same loss pathway. On the slopes under secondary forests, 137Cs mainly existed within the depth 0-24 cm. On the upper middle and middle slope sites, 137Cs had an exponential decrease with depth, indicating no or slight surface erosion; while on the foot slope site, the distribution pattern of 137Cs indicated severer erosion. On the slopes with cultivated lands, 137Cs distributed uniformly within the plough layer. In the upper middle and middle slopes profiles, 137Cs mainly existed in the depth around 15 cm and far less than the background value, indicating severe soil erosion; while in foot slope profiles, 137Cs was aggraded to the depth 45 cm. A discontinuous distribution of 137Cs in the profiles was detected on the foot slopes under secondary forests, on the upper middle and foot slopes of cultivated lands, and in the fissures, indicating that the soil particles on Karst slopes had a trend of losing with rainwater to the underground, but the loss quantity was negligible, compared with surface erosion.

  18. [137Cs profile distribution character and its implication for soil erosion on Karst slopes of northwest Guangxi].

    PubMed

    Feng, Teng; Chen, Hong-song; Zhang, Wei; Nie, Yun-peng; Wang, Ke-lin

    2011-03-01

    This paper studied the profile distribution characters of 137Cs and soil organic carbon (SOC) on the Karst slopes and in the fissures in typical peak-cluster depression in Northwest Guangxi, aimed to approach the applicability of 137Cs method on Karst slopes and the implication of 37Cs for the characteristics of slope soil erosion. In all test profiles, there was a significant correlation between 137Cs and SOC, indicating that both of them might have the same loss pathway. On the slopes under secondary forests, 137Cs mainly existed within the depth 0-24 cm. On the upper middle and middle slope sites, 137Cs had an exponential decrease with depth, indicating no or slight surface erosion; while on the foot slope site, the distribution pattern of 137Cs indicated severer erosion. On the slopes with cultivated lands, 137Cs distributed uniformly within the plough layer. In the upper middle and middle slopes profiles, 137Cs mainly existed in the depth around 15 cm and far less than the background value, indicating severe soil erosion; while in foot slope profiles, 137Cs was aggraded to the depth 45 cm. A discontinuous distribution of 137Cs in the profiles was detected on the foot slopes under secondary forests, on the upper middle and foot slopes of cultivated lands, and in the fissures, indicating that the soil particles on Karst slopes had a trend of losing with rainwater to the underground, but the loss quantity was negligible, compared with surface erosion. PMID:21657012

  19. Spatial uncertainty of the 137Cs reference inventory for Australian soil

    NASA Astrophysics Data System (ADS)

    Chappell, Adrian; Hancock, Gary; Viscarra Rossel, Raphael A.; Loughran, Robert

    2011-12-01

    Soil erosion threatens the productivity of agricultural land, reduces the soil's ability to store water, promotes losses of nutrients, organic matter and soil biota and increases the amount of dust carried by wind. It is difficult to measure directly, particularly over time periods with sufficient duration to represent its variability. The caesium-137 (137Cs) technique estimates net soil redistribution by the combined effect of wind, water and tillage erosion. Used with a single sampling campaign, the 137Cs technique provides retrospective estimates for a given location on medium-term (30-40 years) erosion or deposition rates. In 1990 a national reconnaissance survey of soil erosion in Australia was performed using 137Cs. The aim here is to use the results of that national inventory to establish with spatial uncertainty a preliminary baseline map of the 137Cs reference inventory for Australia to subsequently estimate net (mid 1950s to early 1990s) soil redistribution for Australia. We used an indicator co-simulation between 141 samples of the 137Cs reference inventory and gridded mean annual (1954-1990) rainfall and compared the results with a deterministic method using rainfall and latitude. The former produced a baseline map which reconstructed the spatial data with less bias and smaller uncertainty than the latter. The Australian 137Cs reference inventory map can be improved over time with additional samples and the improved map used for subsequent soil redistribution assessments. Where sufficient data exist the geostatistical method may provide similarly reliable 137Cs reference inventory estimates at unsampled locations around the world.

  20. Radiolead (210)Pb and (210)Po/(210)Pb activity ratios in calcium supplements and the assessment of their possible dose to consumers.

    PubMed

    Strumińska-Parulska, Dagmara I

    2016-08-23

    This paper presents the results of pioneer study of the most popular calcium supplements as a potential additional source of radiolead (210)Pb in human diet. The analyzed calcium pharmaceutics contained organic or inorganic calcium compounds; some came from natural sources as mussels' shells, fish extracts, or sedimentary rocks. The idea was to investigate the naturally occurring (210)Pb activity in different calcium supplements and calculate the annual effective radiation dose from radiolead (210)Pb decay in consumed calcium supplement. The results showed (210)Pb concentrations in natural origin calcium supplements (especially sedimentary rocks) were significantly higher. The highest (210)Pb activity concentrations were determined in mineral tablets made from dolomite - 2.97 ± 0.18 mBq g(-1), while the lowest was observed in organic calcium compounds - both calcium lactate - 0.08 ± 0.01 and 0.13 ± 0.01 mBq g(-1). The highest annual radiation dose from (210)Pb taken with 1 tablet of calcium supplement per day was calculated for soluble calcium lactate sample - 1.19 ± 0.03 µSv year(-1), while the highest annual radiation dose from (210)Pb taken daily with 1 g of pure Ca for dolomite - 5.57 ± 0.34 µSv year(-1).

  1. Radiolead (210)Pb and (210)Po/(210)Pb activity ratios in calcium supplements and the assessment of their possible dose to consumers.

    PubMed

    Strumińska-Parulska, Dagmara I

    2016-08-23

    This paper presents the results of pioneer study of the most popular calcium supplements as a potential additional source of radiolead (210)Pb in human diet. The analyzed calcium pharmaceutics contained organic or inorganic calcium compounds; some came from natural sources as mussels' shells, fish extracts, or sedimentary rocks. The idea was to investigate the naturally occurring (210)Pb activity in different calcium supplements and calculate the annual effective radiation dose from radiolead (210)Pb decay in consumed calcium supplement. The results showed (210)Pb concentrations in natural origin calcium supplements (especially sedimentary rocks) were significantly higher. The highest (210)Pb activity concentrations were determined in mineral tablets made from dolomite - 2.97 ± 0.18 mBq g(-1), while the lowest was observed in organic calcium compounds - both calcium lactate - 0.08 ± 0.01 and 0.13 ± 0.01 mBq g(-1). The highest annual radiation dose from (210)Pb taken with 1 tablet of calcium supplement per day was calculated for soluble calcium lactate sample - 1.19 ± 0.03 µSv year(-1), while the highest annual radiation dose from (210)Pb taken daily with 1 g of pure Ca for dolomite - 5.57 ± 0.34 µSv year(-1). PMID:27253716

  2. 137Cs re-sampling as a method for soil erosion assessment in Alpine grasslands

    NASA Astrophysics Data System (ADS)

    Arata, Laura; Meusburger, Katrin; Bissig, Nicole; Mabit, Lionel; Alewell, Christine

    2014-05-01

    Over the past decades, radioactive fallout 137Cs has been used as a tracer to provide information on soil erosion and sedimentation rates. However, the method may produce relatively large uncertainties in Alpine grasslands. The latter difficulties are caused by a combination of (i) the heterogeneous distribution of atmospheric 137Cs Chernobyl fallout, (ii) the partly snow covered ground in Alpine areas during the fallout event in April 1986, which results in inhomogeneous 137Cs distribution during snow melt and (iii) uncertainties in finding undisturbed references sites in the geomorphological and anthropogenic highly active slopes of the Alps. To overcome these difficulties, our aim is to replace the classical 137Cs approach, where an undisturbed reference site is compared to erosional sites, with a re-sampling approach, where we re-sample sites which have already been measured for 137Cs inventories in the past. Thus, we use temporal instead of spatial reference. The study area is located in the Central Swiss Alps in the Urseren Valley. Potential erosional sites have been sampled in 2007 and re-sampled in 2012. Two different grassland types were investigated: hayfield (2 sites) and pasture without dwarf shrubs (3 sites). For each site, 4 to 9 sampling points have been defined, and at each point two soil samples have been collected. To reduce the random error, the two soil samples were bulked prior to gamma-analysis. 137Cs inventories of the two sampling years were calculated and used to assess recent soil erosion in the experimental sites. Our results show that within the 5 years measurable soil erosion and deposition processes have occurred within the sites, as indicated by the relevant difference between the 137Cs inventories of 2007 and 2012. 64% of the sites exhibit a decrease in 137Cs inventories, 20% of the sites an increase, and the remaining 16% no significant difference. In particular, hayfield sites have been affected by erosion processes, mostly due to

  3. Distribution and Retention of 137Cs in Sediments at the Hanford Site, Washington

    SciTech Connect

    McKinley, James P.; Zeissler, C. J.; Zachara, John M.; Serne, R. Jeffrey; Lindstrom, Richard M.; Schaef, Herbert T.; Orr, Robert D.

    2001-07-25

    {sup 137}Cesium and other contaminants have leaked from high level waste (HLW) single-shell storage tanks (SSTs) at the Hanford Site in southeastern Washington. {sup 137}Cesium and other contaminants have leaked from single-shell storage tanks (SSTs) into coarse-textured, relatively unweathered unconsolidated sediments. Contaminated sediments were retrieved from beneath a leaky SST to investigate the distribution of adsorbed {sup 137}Cs{sup +} across different sediment size fractions. All fractions contained mica (biotite, muscovite, vermiculatized biotite), quartz, and plagioclase along with smectite and kaolinite in the clay-size fraction. A phosphor-plate autoradiograph method was used to identify particular sediment particles responsible for retaining {sup 137}Cs{sup +}. The Cs-bearing particles were found to be individual mica flakes or agglomerated smectite, mica, quartz, and plagioclase. Of these, only the micaceous component was capable of sorbing Cs{sup +} strongly. Sorbed {sup 137}Cs{sup +} could not be significantly removed from sediments by leaching with dithionite citrate buffer or KOH, but a fraction of the sorbed {sup 137}Cs{sup +} (5?22%) was desorbable with solutions containing an excess of Rb{sup +}. The small amount of {sup 137}Cs{sup +} that might be mobilized by migrating fluids in the future would likely sorb to nearby micaceous clasts in downgradient sediments.

  4. 137Cs and 90Sr behavioural regularities in the southeastern part of the Baltic Sea.

    PubMed

    Styro, D; Bumeliene, Z; Lukinskiene, M; Morkuniene, R

    2001-01-01

    Variations in 137Cs concentrations were investigated over the period 1986-1997 in the southeastern part of the Baltic Sea, following the Chernobyl power plant accident. The rate of "self-cleaning" was demonstrated to be very slow, the average concentration of 137Cs in 1996 being almost the same as that measured directly after the accident, in 1986. Measurements of both 137Cs and 90Sr concentrations generally revealed homogeneous distributions in this region of the Baltic Sea, though patchy distributions did develop under some hydrometeorological conditions. Specifically, the 137Cs concentration distribution became heterogeneous with values varying in the range 60-92 Bq/m3 under south-southwesterly wind conditions whilst the 90Sr concentration distribution developed similar characteristics with values ranging from 15 to 64 Bq/m3 under east-southeasterly wind conditions. In addition, in coastal waters, over extensive periods of north-northwesterly winds in 1995, 137Cs concentrations increased to values 1.5-2 times the overall average concentration, which was registered in 1986 and 1996. These data therefore reveal a continuing significant pollution of the waters of the Baltic Sea resulting from the Chernobyl power plant accident, a pollution compounded by the slow rate of radionuclide self-cleaning and significant probability of sudden regional concentration increase.

  5. Accuracy of post-bomb 137Cs and 14C in dating fluvial deposits

    USGS Publications Warehouse

    Ely, L.L.; Webb, R.H.; Enzel, Y.

    1992-01-01

    The accuracy and precision of 137Cs and 14C for dating post-1950 alluvial deposits were evaluated for deposits from known floods on two rivers in Arizona. The presence of 137Cs reliably indicates that deposition occurred after intensive above-ground nuclear testing was initiated around 1950. There was a positive correlation between the measured level of 137Cs activity and the clay content of the sediments, although 137Cs was detected even in sandy flood sediments with low clay content. 137Cs is a valuable dating tool in arid environments where organic materials for 14C or tree-ring dating are scarce and observational records are limited. The 14C activity measured in different types of fine organic detritus yielded dates within 1 to 8 yr of a 1980 flood deposit, and the accuracy was species-dependent. However, undifferentiated mixtures of fine organic materials from several post-bomb deposits of various ages repeatedly yielded dates between 1958 and 1962, and detrital charcoal yielded a date range of 1676-1939. In semiarid environments, the residence time of most types of organic debris precludes accurate annual resolution of post-bomb 14C dates. ?? 1992.

  6. 137Cs and 90Sr transfer to milk in Austrian alpine agriculture.

    PubMed

    Lettner, H; Hubmer, A; Bossew, P; Strebl, F

    2007-01-01

    The alpine regions of Austria were among the most contaminated territories outside of the former USSR after the Chernobyl accident. In the investigated province of Salzburg the median (137)Cs surface deposition was 31.4 kBq m(-2) with maximum values exceeding 90 kBq m(-2) (May 1986). To quantify the transfer of (137)Cs and (90)Sr from vegetation to milk in these seminatural conditions nine seasonally grazed alps were identified and vegetation and milk sampled during summer 2002 and summer 2003. Mean+/-SD milk transfer coefficients (fm) for (137)Cs and (90)Sr were 0.0071+/-0.0009 d l(-1), and 0.0011+/-0.0004 d l(-1), respectively; which for (137)Cs is markedly higher than those fm values found in intensive agricultural systems. Transfer kinetics for (137)Cs into cow milk were approximated using a 2-compartment model with a short and a long-term component. Fitting the model to empirical data results in reliable estimates of the time constant of the short-term component, biological half-life 1.06+/-0.28 d, whereas the estimates of the long-term component are subject to high uncertainties.

  7. Monitoring 137Cs and 134Cs at marine coasts in Indonesia between 2011 and 2013.

    PubMed

    Suseno, Heny; Prihatiningsih, Wahyu Retno

    2014-11-15

    Environmental samples (seawater, sediments and biota) were collected along the eastern and western Indonesian coasts between 2011 and 2013 to anticipate the possible impacts of the Fukushima radioactive releases in Indonesia. On the eastern coasts (south and north Sulawesi), the (137)Cs concentrations in the seawater and sediments were 0.12-0.32 Bq m(-3) and 0.10-1.03 Bq kg(-1), respectively. On the western coasts (West Sumatra, Bangka Island, North Java, South Java and Madura island), the (137)Cs concentrations in the seawater and sediments were 0.12-0.66 Bq m(-3) and 0.19-1.64 Bq kg(-1), respectively. In general, the (137)Cs concentrations in the fish from several Indonesian coasts were 137)Cs concentrations in mollusk, crab and prawn were 10.65-38.78, 4.02 and 6.16 mBq kg(-1), respectively. (134)Cs was not detected in the seawater, sediments or biota. Thus, it was concluded that (137)Cs on the eastern and western Indonesian coasts originated from global fallout.

  8. Prussian Blue decorporation of {sup 137}Cs in beagles of different ages

    SciTech Connect

    Melo, D.R.; Lundgren, D.L.; Muggenburg, B.A.; Guilmette, R.A.

    1996-08-01

    A 6-wk study was conducted using immature (4.7 mo), young adult (2.4 y), and aged (13.5 y) male beagles to determine the modifying effect of age on the effectiveness of Prussian Blue decorporation therapy for the removal of injected {sup 137}Cs. Whole-body clearance rates for injected {sup 137}Cs decreased with increasing age in the dogs. Treatment with Prussian Blue changed the ratio of fecal to urinary {sup 137}Cs excretion from 0.8 in untreated dogs to 2.2 in treated animals. The {sup 137}Cs concentrations in tissues of untreated and Prussian Blue-treated dogs at the end of the 6-wk study were similar, with the greatest concentrations in the skeletal muscle tissue, spleen, and kidneys. There was a lower concentration of {sup 137}Cs in the livers of the treated dogs. The reductions in the average total whole-body doses resulting from Prussian Blue treatment during the course of this study were 51% in the immature, 31% in the young adult, and 38% in the aged dogs. Because of the differences in the intake of Prussian Blue by the dogs in the different groups relative to their body weight, it is unclear as to the relative effectiveness of Prussian Blue in dogs of different ages. 33 refs., 1 fig., 5 tabs.

  9. Seasonal 7Be and 137Cs activities in surface air before and after the Chernobyl event.

    PubMed

    Kulan, A

    2006-01-01

    Seasonal fluctuations of cosmogenic (7)Be (T(1/2)=53.4 days) and anthropogenic (137)Cs (T(1/2)=30 years) activities in surface air (aerosols) have been extracted from a long data record (1972-2000) at high latitude (56 degrees N-68 degrees N, Sweden). Normalization to weekly average values was used to control long-term trends so that cyclical trends could be investigated. Enhanced (7)Be activity was observed in spring and summer seasons and likely relates to the seasonal thinning of the tropopause. Variations in the (137)Cs activity record seem to reflect how the isotope was injected in the atmosphere (stratospheric from bomb tests and tropospheric from the Chernobyl accident) and subsequent transport mechanisms. Accordingly, until 1986, the surface air (137)Cs activity was strongly related to nuclear weapons test fallout and exhibits temporal fluctuations resembling the (7)Be. Conversely, since 1986 the Chernobyl-produced (137)Cs dominates the long-term record that shows annual cycles that are strongly controlled by atmospheric boundary layer conditions. Additionally, short-term data within the post-Chernobyl period suggest subtle intrusion of air masses rich in (137)Cs that may occur throughout the year, and differences resulting from spatial occurrence at these latitudes. This is an important observation that may have to do with year-to-year variation and calls for caution when interpreting short-term data records. PMID:16876295

  10. Porous Alumina Silicate Matrix Gubka for Solidification of {sup 137}Cs Strip Product

    SciTech Connect

    Aloy, Albert; Strelnikov, Alexander; Essimantovskiy, Vyacheslav

    2007-07-01

    Separated liquid high-level radioactive waste (HLW) fractions, in particular, about 100 liters of a {sup 137}Cs strip product with activity up to {approx} 100 Ci/l (3.7 TBq/l) have been produced during the development and testing of partitioning technology and temporarily stored at V.G. Khlopin Radium Institute (KRI) (Saint-Petersburg, Russia). The bench-scale experimental unit designed for operation in the hot cell was developed for {sup 137}Cs strip product solidification using an alumina silicate porous inorganic material (PIM) called Gubka. Conditions of saturation, drying, and calcinations of the salts into Gubka pores were optimized, and the operations under a remote control regime were executed during tests using a simulated strip product doped with {sup 137}Cs. The volume reduction coefficients were equal by a factor of 3.2-3.9 and a {sup 137}Cs discharge into an off-gas system was not detected. {sup 137}Cs leach rates from Gubka blocks after calcination at 800 deg. C were 1.0-1.5.10{sup -3} g/m{sup 2}.per day. (authors)

  11. Determination of low (137)Cs concentration in seawater using ammonium 12-molybdophosphate adsorption and chemical separation method.

    PubMed

    Park, J H; Chang, B U; Kim, Y J; Seo, J S; Choi, S W; Yun, J Y

    2008-12-01

    A new method has been developed for analyzing (137)Cs in a small volume of seawater. Ammonium 12-molybdophosphate (AMP) was used two times during pretreatment procedure. The first step was to adsorb (137)Cs in seawater samples into AMP in order to reduce sample volume, and the second was to remove (87)Rb, interference nuclide for beta counting. The AMP adsorbing (137)Cs was dissolved by sodium hydroxide solution, and then (137)Cs was finally formed to be cesium chloroplatinate precipitate by adding 10% hexachloroplatinic acid. The beta rays emitted from (137)Cs were measured with a low background gas-proportional alpha/beta counter. This method was applied to several seawater samples taken in the East Sea of Korea. Compared to the routinely used gamma-spectrometry method, this new AMP method was reliable and suitable for analyzing (137)Cs in deep seawater. PMID:18799246

  12. Post-depositional redistribution and gradual accumulation of 137Cs in a riparian wetland ecosystem in Sweden.

    PubMed

    Stark, K; Wallberg, P; Nylén, T

    2006-01-01

    After the Chernobyl accident, high activity concentrations of (137)Cs (>1 MBq m(-2)) were detected in a riparian swamp in the central-eastern part of Sweden. The objective of this study was to clarify the redistribution processes behind the accumulation of (137)Cs in the wetland. A mass balance budget of (137)Cs was calculated based on soil and sediment samples and reports in the literature. Results showed that accumulation occurred over several years. Of all the (137)Cs activity discharged between 1986 and 2002 from the upstream lake, 29% was estimated to be retained in the wetland. In 2003, measurements showed that 17 kBq m(-2) sedimented on the stream banks of the wetland. Continuing overbank sedimentation by spring flooding prolongs the time that the wetland will contain high activity concentrations of (137)Cs. Consequently, organisms living in wetlands serving as sinks for (137)Cs may become exposed over long time periods to high activity concentrations.

  13. Factors affecting 137Cs bio- availability under the application of different fertilizing systems

    NASA Astrophysics Data System (ADS)

    Fedorkova, M. V.; Belova, N. I.

    2012-04-01

    Although it has been 25 years since the Chernobyl accident, it was generally found that radiocaesium remained bio-availability in some regions. Plant uptake of 137Cs is depended from quantity of exchangeable radionuclide and strongly influenced by soil properties. The addition of fertilizers to soil induces chemical and biological changes that influence the distribution of free ions the different phases (soil and soil solution). In this study we try to estimate influence of different soil conditions affecting the 137Cs bio-availability under the application of manure and inorganic fertilizers. Our research carried out in 2001-2008 years on contaminated after Chernobyl accident sod-podzolic soil during of prolonged field experiment. The experimental site was located in south-west of Bryansk region, Russia. Contamination density by 137Cs in the sampling point was equal to 475±30 kBq/m2. The sequence of crops in rotation was: 1) potato; 2) oats 3) lupine 4) winter rye. Three fertilizing systems were compared: organic - 80 tons per hectare of cow manure; inorganic fertilizing system - different rates of NPK (low, temperate and high) and mixed - 40 tons per hectare of cow manure + NPK. Main soil properties and chemical form of 137Cs and K (potassium) were detected. Radiocaesium activity was determined in soil and plant samples by gamma spectrometry, using a high purity Ge detectors. Overall efficiency was known to an accuracy of about 10-12%. Obtained results shows, that various fertilizing systems influence soil properties, chemical forms of 137Cs and K in soil and radionuclide soil-to-plant transfer in different ways. The highest reduction of exchangeable 137Cs in soil was found in case with application of organic fertilizers and also - temperate NPK rates. Part of exchangeable 137Cs is equal 6.8% (from total activity) in case of manure, 7.8% in case of inorganic fertilizers with control value - 10.2%. Caesium mobility in soil is affected by such soil properties as

  14. 210Pb-226Ra disequilibria in Icelandic basalts and implications for melt transport time

    NASA Astrophysics Data System (ADS)

    Sigmarsson, O.

    2003-04-01

    Primitive basalts with radioactive disequilibrium between isotopes of the 238U decay chain may provide constraints on the timescales of mantle melt migration. The disequilibria between 238U, 230Th and 226Ra have been studied in several Recent basalts whereas very few results exist on the 210Pb-226Ra disequilibria. Only basalts significantly younger than 100 years old can be studied for 210Pb-226Ra disequilibria due to the short half-live of 210Pb (22.3 years). Most lavas measured so far show either 210Pb-226Ra equilibria or 210Pb-deficit which have been attributed to the degassing of 222Rn in shallow magma chambers. Icelandic tholeiites from the last century are in radioactive equilibrium with (210Pb/226Ra) equal to unity. These basalts are fed from shallow magma chambers having residence time exceeding 100 years. In contrast, primitive alkaline basalts (MgO =7-12%) from Surtsey island had (210Pb/226Ra) ranging from 0.45±0.04 to 0.82±0.06 at the time of eruption. These large 210Pb deficits are unlikely to result from shallow magma degassing since no magma chamber existed beneath this volcanic island which was born during the 1963-67 eruption. The 210Pb-226Ra disequilibria increase from the beginning towards the end of the eruption when the most primitive basalts were produced, and decreases systematically with increasing Th content. These same basalts show a negative correlation between Pb and Cu abundances which are inconsistent with exsolution of sulfur rich liquid or crystallisation of sulphides as a fractionation mechanism of 210Pb and 226Ra. The large deficit of 210Pb in Surtsey lavas were thus most likely generated during mantle partial melting. In such a case, the time of melt transport from the source region to surface is constrained to be significantly shorter than 100 years.

  15. Sediment and (137)Cs behaviors in the Ogaki Dam Reservoir during a heavy rainfall event.

    PubMed

    Kurikami, Hiroshi; Kitamura, Akihiro; Yokuda, Satoru Thomas; Onishi, Yasuo

    2014-11-01

    We performed a simulation of sediment and (137)Cs behaviors in the Ogaki Dam Reservoir, one of the main irrigation reservoirs in the Fukushima prefecture, Japan, during a heavy rainfall event occurred in 2013. The one-dimensional river and reservoir simulation scheme TODAM, Time-dependent One-dimensional Degradation and Migration, was applied for calculating the time dependent migration of sediment and (137)Cs in dissolved and sediment-sorbed forms in the reservoir. Continuous observational data achieved in the upper rivers were used as the input boundary conditions for the simulation. The simulation results were compared with the continuous data achieved in the lower river and we confirmed the predicted values of sediment and (137)Cs in sediment-sorbed form at the exit of reservoir satisfactorily reproduced the observational data. We also performed sediment and (137)Cs behavioral simulation by changing the water level of the reservoir, because such a dam operation could control the quantities of sediment and (137)Cs discharge from and/or deposition in the reservoir. The simulation clarified that the reservoir played an important role to delay and buffer the movement of radioactive cesium in heavy rainfall events and the buffer effect of the reservoir depended on particle sizes of suspended sediment and the water level. It was also understood that silt deposition was the main source of the bed contamination (except for the initial fallout impact), while clay was the main carrier of (137)Cs to the lower river at a later stage of rainfall events. PMID:24980512

  16. Prediction of spatial variation in global fallout of 137Cs using precipitation.

    PubMed

    Pálsson, S E; Howard, B J; Wright, S M

    2006-08-31

    Deposition from atmospheric nuclear weapons tests (termed global fallout) has been shown to be proportional to the rate of precipitation. Here we describe methods for using precipitation and radionuclide deposition information for a reference site to estimate global fallout at other locations. These methods have been used to estimate global fallout in Iceland, identified during the Arctic Monitoring and Assessment Programme (AMAP) by Wright et al. [Wright, S.M., Howard, B.J., Strand, P., Nylén, T., Sickel, M.A.K., 1999. Prediction of 137Cs deposition from atmospheric nuclear weapons tests within the Arctic. Environ Pollut 104, 131-143.] as one of the Arctic areas which received the highest global fallout, but where measurements of contamination were sparse, and difficult to obtain due to the remote and inaccessible terrain of much of the country. Measurements of global fallout 137Cs deposition have been made in Iceland at sites close to meteorological stations to ensure that precipitation data were of high quality. The AMAP modeling approach, based on measured precipitation and radionuclide deposition data, was applied using a reference monitoring station located close to Reykjavik. The availability of good precipitation data and locally based estimates of time dependent ratios of 137Cs deposition to precipitation during the fallout period gave a better correlation between predicted and measured 137Cs global fallout (r2=0.96) than that achieved using the much more heterogeneous set of data collected by AMAP over the whole of the Arctic. Having obtained satisfactory results with the model for a number of calibration sites alongside meteorological stations we then produced a map of estimated 137Cs deposition based on a model of estimated precipitation. This deposition map was then successfully validated (r2=0.85) for sites where 137Cs deposition was measured; the associated uncertainty in predictions was also estimated.

  17. 137Cs and (239+240)Pu levels in the Asia-Pacific regional seas.

    PubMed

    Duran, E B; Povinec, P P; Fowler, S W; Airey, P L; Hong, G H

    2004-01-01

    137Cs and (239+240)Pu data in seawater, sediment and biota from the regional seas of Asia-Pacific extending from 50 degrees N to 60 degrees S latitude and 60 degrees E to 180 degrees E longitude based on the Asia-Pacific Marine Radioactivity Database (ASPAMARD) are presented and discussed. 137Cs levels in surface seawater have been declining to its present median value of about 3 Bq/m3 due mainly to radioactive decay, transport processes, and the absence of new significant inputs. (239+240)Pu levels in surface seawater are much lower, with a median of about 6 mBq/m3. (239+240)Pu appears to be partly scavenged by particles and is therefore more readily transported down the water column. As with seawater, (239+240)Pu concentrations are lower than 137Cs in surface sediment. The median 137Cs concentration in surface sediment is 1.4 Bq/kg dry, while that of (239+240)Pu is only 0.2 Bq/kg dry. The vertical profiles of both 137Cs and (239+240)Pu in the sediment column of coastal areas are different from deep seas which can be attributed to the higher sedimentation rates and additional contribution of run-offs from terrestrial catchment areas in the coastal zone. Comparable data for biota are far less extensive than those for seawater and sediment. The median 137Cs concentration in fish (0.2 Bq/kg wet) is higher than in crustaceans (0.1 Bq/kg wet) or mollusks (0.1 Bq/kg wet). Benchmark values (as of 2001) for 137Cs and (239+240)Pu concentrations in seawater, sediment and biota are established to serve as reference values against which the impact of future anthropogenic inputs can be assessed. ASPAMARD represents one of the most comprehensive compilations of available data on 137Cs and (239+240)Pu in particular, and other anthropogenic as well as natural radionuclides in seawater, sediment and biota from the Asia-Pacific regional seas. PMID:15245845

  18. [Effect of soil radiation pollution on the plant content of 137Cs and biogenic elements].

    PubMed

    Gromova, V S

    2010-01-01

    The paper presents the data of many years' studies of the effect of different soil radiation pollution levels on the plant accumulation of different types of 137Cs and potassium and phosphorus salts. With increased soil radiation levels, not only the plant content of 137Cs becomes higher, but that of potassium and phosphoric acid also changes. The amount of potassium is decreased in the topinambour and increased in the lentils, but only in its seeds; that of potassium and phosphoric acid is increased in all parts of rape.

  19. Natural effective half-life of {sup 137}Cs in tea plants

    SciTech Connect

    Uenlue, M.Y.; Topcuoglu, S.; Kuecuekcezzar, R.

    1995-01-01

    Contamination levels and variation of {sup 137}Cs in tea plant leaves from 1986-1992 were determined over the coast line of the Eastern Black Sea region in Turkey. The decrease of {sup 137}Cs radionuclide concentration in tea plant leaves may be described by a double exponential function with 94.8% activity lost with a T{sub eff} of 125 d and 5.2% activity lost with a T{sub eff} of 1,114 d. 19 refs., 4 figs., 1 tab.

  20. [Modeling the behavior of 137Cs in a soil-plant system after use of ameliorators].

    PubMed

    Spiridonov, S I; Fesenko, S V; Sanzharova, N I

    2001-01-01

    The main processes and mechanisms responsible for 137Cs behaviour in the soil-forest plants system following the application of ameliorants are described. Mathematical models are presented based on the identification of mechanisms governing the physico-chemical and biological processes, a set of which determined the radionuclides uptake by plants. The models parameterization is exemplified by forest soils subjected to radioactive contamination after the Chernobyl accident. Effects of ameliorants and time of their application on 137Cs behaviour in the soil-plant system are assessed. The contribution of soil chemical and biological processes to the decrease in the radionuclide uptake by plants is estimated. PMID:11458650

  1. Accumulation and distributions of {sup 137}Cs in fresh water snail Pila ampullacea

    SciTech Connect

    Suseno, Heny

    2014-10-24

    Pila ampullacea are found in tropical freshwaters of Indonesia. This snail exhibit several characteristics of ideal indicator organisms in order to understand the bioaccumulation of {sup 137}Cs. Biokinetic experiment was performaced in aquaria system and under influenced of concentration K{sup +} in water. The result of experiment shown that Under difference K{sup +} concentration in water, Pila ampullacea have capability to accumulated {sup 137}Cs with CF value range 8.95 to 12.52 ml.g{sup −1}. Both uptake and depuration rate were influenced by concentration of K{sup +} in water.

  2. Excretion rates of 210Po and 210Pb in Prague inhabitants.

    PubMed

    Hölgye, Zoltán

    2013-01-01

    Excretion rates of (210)Po and (210)Pb in the urine were investigated in 40 healthy inhabitants of Prague (22 males, 18 females, age: 23-70 y, non-smokers). In 20 inhabitants the excretion rates of (210)Po and (210)Pb in faeces were also studied. The mean urinary excretion rates of (210)Po and (210)Pb were 4.1 and 6.0 mBq d(-1), respectively. It was demonstrated, statistically, that the urinary excretion rates of (210)Po and (210)Pb are higher in men than those in women. The highest excretion rates of (210)Po and (210)Pb found in the participants were 10.8 and 16.6 mBq d(-1), respectively. The mean activity ratio of (210)Po/(210)Pb in the urine was 0.73. The mean excretion rates of (210)Po and (210)Pb in faeces were 56.5 and 54.6 mBq d(-1). The mean activity ratio of (210)Po/(210)Pb in faeces was 1.0.

  3. Skeletal sup 210 Pb from inhalation of sup 222 Rn and its decay products

    SciTech Connect

    Keane, A.T.; Schlenker, R.A.; Stebbings, J.H.

    1990-01-01

    Concern about health effects of radon and its decay products has recently broadened to include the potential role of radon in the causation of myeloid leukemia, multiple myeloma, and melanoma, kidney cancer, and certain childhood cancers. Description of the distribution of radon and its daughters in the skeleton and the marrow, and the dose delivered to red marrow, are of particular relevance. Our interest in a metabolic model for inhaled radon and radon decay products originated with an interest in the use of radioactivity measurement techniques in vivo to quantify the {sup 210}Pb activity of bone. In this paper we estimate the rates of transfer to body fluids of {sup 210}Pb originating from inhaled radon and radon decay products and the quantity of {sup 210}Pb deposited in compact and in cancellous bone for the ideal case of continuous exposure to a constant level of radon and its daughters. We review the contributions of ambient airborne {sup 210}Pb, diet, and active and passive smoking to skeletal levels of {sup 210}Pb, and finally, from the magnitude and the variability of the natural {sup 210}Pb content of the skeleton, we estimate the minimal rate of exposure to airborne radon and its decay products that is required to elevate the skeletal {sup 210}Pb content of an individual to a statistically significant level above the population mean skeletal {sup 210}Pb content derived from all the other environmental sources combined. 55 refs., 4 tabs.

  4. A simple model of 222Rn accumulation leading to 210Pb excesses in volcanic rocks

    NASA Astrophysics Data System (ADS)

    Condomines, M.; Sigmarsson, O.; Gauthier, P. J.

    2010-05-01

    While most rocks from active volcanoes display (210Pb/226Ra) activity ratios lower than or close to the equilibrium value of 1, several other have ratios much higher than 1. Transfer of 222Rn by magmatic volatiles has often been advocated to explain both 210Pb deficits and excesses. We develop here a model to account for 210Pb excesses through 222Rn accumulation. We show that large 210Pb excesses can be readily obtained, even for moderate ratios of degassing magma over accumulating magma, in a closed-system model where the 222Rn atoms produced by decay of 226Ra in the degassing magma are continuously extracted by a gas phase. For a given duration of volatile transfer, relative 210Pb excesses are expected to be much larger than 210Pb deficits. This model is applied to samples from Santorini (Aegean arc) and Surtsey (Iceland) both of which show high (210Pb/226Ra) ratios of 6.7 and 2.3 respectively at the time of eruption. The agreement with field data suggests that 222Rn accumulation leading to 210Pb excesses might be a rather common process in zoned magma chambers as well as in individual lava flows, and that it can be described by a closed-system model.

  5. 137Cs concentration in meat of wild boars (Sus scrofa) in Croatia a decade and half after the Chernobyl accident.

    PubMed

    Vilic, M; Barisic, D; Kraljevic, P; Lulic, S

    2005-01-01

    Gamma-spectrometric measurements of 137Cs activities in meat of wild boars collected in Croatia at several locations with different levels of 137Cs contamination are presented. Samples were collected during the period between 2000 and 2002, about 15 years after the Chernobyl accident. 137Cs concentrations ranged over three orders of magnitude: 0.4-611.5 Bq kg(-1). On the basis of these results, 137Cs concentrations at researched areas could be categorized into three groups: (i) the area of Slavonski Brod, Lipik and Slunj with 137Cs concentrations in meat of only a few Bq kg(-1); (ii) the area of Vrbovsko and Sirac with 137Cs concentrations of a few tens of Bq kg(-1); and (iii) the Fuzine area with 137Cs values in wild boar meat of a few hundreds of Bq kg(-1). In areas with approximately equal contamination level, 137Cs concentrations in wild boar meat varied over two orders of magnitude. This fact suggests that the main reason for high 137Cs values in wild boar meat could be due to food consumed by wild boars, and only secondarily in contamination level of area where they live. Intensive mushroom consumption during autumn months could be one of the factors responsible for high 137Cs values in wild boar meat. An average dose arising from 137Cs due to ingestion of wild boar meat in Croatia is below radiological health concern except in the area of Fuzine, and only in cases of high annual wild boar meat intake, probably by hunters or members of their families.

  6. Potential of Chromolaena odorata for phytoremediation of (137)Cs from solution and low level nuclear waste.

    PubMed

    Singh, Shraddha; Thorat, Vidya; Kaushik, C P; Raj, Kanwar; Eapen, Susan; D'Souza, S F

    2009-03-15

    Potential of Chromolaena odorata plants for remediation of (137)Cs from solutions and low level nuclear waste was evaluated. When plants were exposed to solutions spiked with three different levels of (137)Cs, namely 1 x 10(3) kBqL(-1), 5 x 10(3) kBqL(-1) and 10 x 10(3) kBqL(-1), 89%, 81% and 51% of (137)Cs was found to be remediated in 15 d, respectively. At the lowest Cs activity (1 x 10(3) kBqL(-1)), accumulation of Cs was found to be higher in roots compared to shoots, while at higher Cs activities (5 x 10(3) kBqL(-1) and 10 x 10(3) kBqL(-1)), Cs accumulation was more in shoots than roots. When plants were incubated in low level nuclear waste, 79% of the activity was removed by plants at the end of 15 d. The present study suggests that C. odorata could be used as a potential candidate plant for phytoremediation of (137)Cs.

  7. Effective and ecological half-lives of 137Cs in cow's milk in alpine agriculture.

    PubMed

    Lettner, Herbert; Hubmer, Alexander; Bossew, Peter; Strebl, Friederike; Steinhäusler, Friedrich

    2009-02-01

    In the mountainous "Hohe Tauern" region of Salzburg (Austria), milk samples have been collected in a long-term montitoring programme since 1988, at eight alpine sites used for extensive, seasonal stock farming. For this alpine environment with its acidic soils developed on silicate bedrock, high soil-to-plant transfer factors and long-lasting (137)Cs contamination levels in milk--the main product of seasonal agriculture at elevated altitudes--are characteristic features. The decrease in (137)Cs concentration in milk measured since 1988 turned out to be best described by one or two effective half-lives. For the period from 1993 to 2007, which can be modelled with one effective half-life for all sites, effective half-lives between 3.7 and 15.0 years (ecological half-lives: 4.3-29.9 years) were obtained. The effective half-life increases with mean altitude of the investigated graze pastures, probably due to reduced migration velocities of (137)Cs and low (137)Cs half-value depths of a few centimetres in the soil.

  8. Depth distribution of (137)Cs in anthrosol from the experimental field "Radmilovac" near Belgrade, Serbia.

    PubMed

    Vukašinović, Ivana; Todorović, Dragana; Dorđević, Aleksandar; Rajković, Miloš B; Pavlović, Vladimir B

    2013-09-01

    This is a preliminary study of the depth distribution of (137)Cs radionuclides in cultivated anthrosol soil of a 15-year old peach tree plantation at the experimental field "Radmilovac" near Belgrade. Before planting, the soil was ploughed at the depth of 1 m. The soil had not been annually ploughed, irrigated and treated with mineral fertilizers for three years before sampling. Activity concentration for (137)Cs ranged from 1.8 Bq kg(-1) to 35 Bq kg(-1). Along the soil depth it varied highly, reaching as high a total variation coefficient as 83 %. Radiocaesium distribution patterns depended on the extent of soil mixing in the plough layer, as it was mechanically transferred from the surface to the lower soil layers during cultivation. (137)Cs was associated with humus content and fixation to clay fractions in the soil. Our results single out soil's hygroscopic water as a valuable parameter for (137)Cs behaviour that could be used commonly if the measurement is standardised. PMID:24084351

  9. Distribution of 90Sr and 137Cs in Arctic soil profiles polluted by heavy metals.

    PubMed

    Puhakainen, M; Heikkinen, T; Steinnes, E; Thørring, H; Outola, I

    2005-01-01

    Effects of industrial pollution on the behaviour of radionuclides in spruce forest ecosystems were studied along a gradient from of a copper-nickel smelter in Monchegorsk, NW Russia. A reference site was situated in Lapland, Finland, 152 km west of Monchegorsk. Most of the total 137Cs activity in soil was in mineral (E and B) horizons, except at the reference site where the major part was still in the organic surface layer. Most of the total 90Sr activity still remaining in the soil profile was found in the surface layer, but the relative amount decreased with increasing level of industrial pollution. Pollutants from the smelter clearly affected the chemical speciation of radionuclides. Smaller amounts of exchangeable radionuclides were present in the organic surface layer at the most polluted sites. The decline of 137Cs with decreasing distance from the smelter correlated strongly with a similar depletion in exchangeable K and Mg. Total concentrations of 137Cs and 90Sr showed high correlations with exchangeable cations, particularly in the E and upper B horizon. A sudden change in behaviour of 137Cs in the lower B horizon may be associated with changes in clay mineralogy along the soil profile caused by weathering.

  10. Ecological half-life of 137Cs in plants associated with a contaminated stream.

    PubMed

    Peles, John D; Smith, Michael H; Brisbin, I Lehr

    2002-01-01

    Ecological half-life (Te) is a useful measure for studying the long-term decline of contaminants, such as radionuclides, in natural systems. The current investigation determined levels of radiocesium (137Cs) in two aquatic (Polygonum punctatum, Sagittaria latifolia) and three terrestrial (Alnus serrulata, Myrica cerifera, Salix nigra) plant species from a contaminated stream and floodplain on the U.S. Department of Energy's Savannah River Site. Current 137Cs levels in plants were used in conjunction with historical data to determine Te of 137Cs in each species. Median concentrations of 137Cs were highest in S. latifolia (0.84 Bq g(-1)) and lowest in M. cerifera (0.10 Bq g(-1)). Te's ranged from 4.85 yr in M. cerifera to 8.35 yr in S. nigra, both terrestrial species. Te's for all aquatic (6.30 yr) and all terrestrial (5.87) species combined were very similar. The Te's of the two aquatic primary producers (P. punctatum and S. latifolia) in the Steel Creek ecosystem were somewhat longer than Te values previously reported for some consumers from this ecosystem.

  11. 137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska

    SciTech Connect

    Hamilton, T F; Seagars, D J; Jokela, T; Layton, D

    2005-02-02

    The activity concentration of Cesium-137 ({sup 137}Cs) and naturally-occurring Polonium-210 ({sup 210}Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean {sup 137}Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg{sup -1} (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg{sup -1} (N=2, wet weight), respectively, in bearded seal. In general, {sup 137}Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, {sup 210}Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean {sup 210}Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg{sup -1}, respectively. This compares with {sup 210}Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg{sup -1} measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for {sup 210}Po that those of {sup 137}Cs. We conclude from radiological dose estimates that ingestion of {sup 137}Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic.

  12. Enviromental influences on the {sup 137}Cs kinetics of the yellow-bellied turtle (Trachemys Scripta)

    SciTech Connect

    Peters, E.L.; Brisbin, L.I. Jr.

    1996-02-01

    Assessments of ecological risk require accurate predictions of contaminant dynamics in natural populations. However, simple deterministic models that assume constant uptake rates and elimination fractions may compromise both their ecological realism and their general application to animals with variable metabolism or diets. In particular, the temperature-dependent model of metabolic rates characteristic of ectotherms may lead to significant differences between observed and predicted contaminant kinetics. We examined the influence of a seasonally variable thermal environment on predicting the uptake and annual cycling of contaminants by ectotherms, using a temperature-dependent model of {sup 137}Cs kinetics in free-living yellow-bellied turtles, Trachemys scripta. We compared predictions from this model with those of deterministics negative exponential and flexibly shaped Richards sigmoidal models. Concentrations of {sup 137}Cs in a population if this species in Pond B, a radionuclide-contaminated nuclear reactor cooling reservoir, and {sup 137}Cs uptake by the uncontaminated turtles held captive in Pond B for 4 yr confirmed both the pattern of uptake and the equilibrium concentrations predicted by the temperature-dependent model. Almost 90% of the variance on the predicted time-integrated {sup 137}Cs concentration was explainable by linear relationships with model paramaters. The model was also relatively insensitive to uncertainties in the estimates of ambient temperature, suggesting that adequate estimates of temperature-dependent ingestion and elimination may require relatively few measurements of ambient conditions at sites of interest. Analyses of Richards sigmoidal models of {sup 137}Cs uptake indicated significant differences from a negative exponential trajectory in the 1st yr after the turtles` release into Pond B. 76 refs., 7 figs., 5 tabs.

  13. 137Cs and 210Po in Pacific walrus and bearded seal from St. Lawrence Island, Alaska.

    PubMed

    Hamilton, Terry; Seagars, Dana; Jokela, Terry; Layton, David

    2008-06-01

    The activity concentration of Cesium-137 ((137)Cs) and naturally-occurring Polonium-210 ((210)Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea during May 1996. The mean (137)Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg(-1) (n=5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg(-1) (n=2, wet weight), respectively, in bearded seal. In general, (137)Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, (210)Po activity concentrations are more variable and appear to be higher level compared with mammal data from other regions. The mean (210)Po concentration in the muscle tissue, liver and kidney of Pacific walrus (n=5, wet weight) were 28.7, 189, and 174 Bq kg(-1), respectively. This compares with (210)Po concentration values (n=2, wet weight) of 27, 207 and 68 Bq kg(-1) measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated concentration factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for (210)Po that those of (137)Cs. We conclude from radiological dose estimates that ingestion of (137)Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessment of risks of Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic.

  14. Gene Expression Response of Mice after a Single Dose of 137Cs as an Internal Emitter

    PubMed Central

    Paul, Sunirmal; Ghandhi, Shanaz A.; Weber, Waylon; Doyle-Eisele, Melanie; Melo, Dunstana; Guilmette, Raymond; Amundson, Sally A.

    2014-01-01

    Cesium-137 is a radionuclide of concern in fallout from reactor accidents or nuclear detonations. When ingested or inhaled, it can expose the entire body for an extended period of time, potentially contributing to serious health consequences ranging from acute radiation syndrome to increased cancer risks. To identify changes in gene expression that may be informative for detecting such exposure, and to begin examining the molecular responses involved, we have profiled global gene expression in blood of male C57BL/6 mice injected with 137CsCl. We extracted RNA from the blood of control or 137CsCl-injected mice at 2, 3, 5, 20 or 30 days after exposure. Gene expression was measured using Agilent Whole Mouse Genome Microarrays, and the data was analyzed using BRB-ArrayTools. Between 466–6,213 genes were differentially expressed, depending on the time after 137Cs administration. At early times (2–3 days), the majority of responsive genes were expressed above control levels, while at later times (20–30 days) most responding genes were expressed below control levels. Numerous genes were overexpressed by day 2 or 3, and then underexpressed by day 20 or 30, including many Tp53-regulated genes. The same pattern was seen among significantly enriched gene ontology categories, including those related to nucleotide binding, protein localization and modification, actin and the cytoskeleton, and in the integrin signaling canonical pathway. We compared the expression of several genes three days after 137CsCl injection and three days after an acute external gamma-ray exposure, and found that the internal exposure appeared to produce a more sustained response. Many common radiation-responsive genes are altered by internally administered 137Cs, but the gene expression pattern resulting from continued irradiation at a decreasing dose rate is extremely complex, and appears to involve a late reversal of much of the initial response. PMID:25162453

  15. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi. PMID:26690320

  16. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi.

  17. Persistence of 137Cs in the litter layers of forest soil horizons of Mount IDA/Kazdagi, Turkey.

    PubMed

    Karadeniz, Özlem; Karakurt, Hidayet; Çakır, Rukiye; Çoban, Fatih; Büyükok, Emir; Akal, Cüneyt

    2015-01-01

    In 2010-2012, an extensive study was performed in forest sites of Mount IDA (Kazdagi)/Edremit 26 years after the Chernobyl accident. The (137)Cs activity concentrations were determined by gamma-ray spectrometry in the forest soil layers (OL, OF + OH and A horizons) separately. Based on 341 surface soil samples and 118 soil profiles, activity concentrations of (137)Cs in OL horizons varied between 0.25 ± 0.14 and 70 ± 1 Bq kg(-1), while the ranges of (137)Cs activity concentrations in OF + OH and A horizons were 13 ± 1-555 ± 3 Bq kg(-1) and 2 ± 1-253 ± 2 Bq kg(-1), respectively. Cesium-137 deposition in the study area was estimated to be in the range of 1-39 kBq m(-2) and a linear relationship between the deposition of (137)Cs and the altitude was observed. The distributions of (137)Cs activities in OL, OF + OH and A horizons throughout the region were mapped in detail. The highest (137)Cs activities were found in OF + OH horizons, with markedly lower (137)Cs activity in mineral horizons of soil profiles. It is observed that (137)Cs content of humus layer increases with the thickness of the humus layer for coniferous forest sites. The (137)Cs activity concentrations were higher than the recommended screening limits (150 Bq kg(-1)) at some of the investigated areas. The current activity concentration of top soil layers indicates that over many years since the initial deposition, (137)Cs activity is keeping still high in the organic horizons. PMID:25464048

  18. Analysis of 50-y record of surface (137)Cs concentrations in the global ocean using the HAM-global database.

    PubMed

    Inomata, Yayoi; Aoyama, Michio; Hirose, Katsumi

    2009-01-01

    We investigated spatial and temporal variations in (137)Cs concentrations in the surface waters of the global ocean for the period from 1957 to 2005 using the "HAM database - a global version". Based on the 0.5-y average value of (137)Cs concentrations in the surface water in each sea area, we classified the temporal variations into four types. (1) In the North Pacific Ocean where there was high fallout from atmospheric nuclear weapons tests, the rates of decrease in the (137)Cs concentrations changed over the five decades: the rate of decrease from the 1950s to the 1970s was much faster than that after the 1970s, and the (137)Cs concentrations were almost constant after the 1990s. Latitudinal differences in (137)Cs concentrations in the North Pacific Ocean became small with time. (2) In the equatorial Pacific and Indian Oceans, the (137)Cs concentrations varied within a constant range in the 1970s and 1980s, suggesting the advection of (137)Cs from areas of high global fallout in the mid-latitudes of the North Pacific Ocean. (3) In the eastern South Pacific and Atlantic Oceans (south of 40 degrees S), the concentrations decreased exponentially over the five decades. (4) In the Arctic and North Atlantic Oceans, including marginal seas, (137)Cs concentrations were strongly controlled by discharge from nuclear reprocessing plants after the late 1970s. The apparent half-residence times of (137)Cs in the surface waters of the global ocean from 1970 to 2005 ranged from 4.5 to 36.8 years. The apparent half-residence times were longer in the equatorial region and shorter in the higher latitudes. There was no notable difference between the latitudinal distributions of the apparent half-residence times in the Pacific and Indian Oceans. These results suggest that (137)Cs in the North Pacific Ocean is transported to the equatorial, South Pacific, and Indian Oceans by the oceanic circulation. PMID:19137147

  19. Persistence of 137Cs in the litter layers of forest soil horizons of Mount IDA/Kazdagi, Turkey.

    PubMed

    Karadeniz, Özlem; Karakurt, Hidayet; Çakır, Rukiye; Çoban, Fatih; Büyükok, Emir; Akal, Cüneyt

    2015-01-01

    In 2010-2012, an extensive study was performed in forest sites of Mount IDA (Kazdagi)/Edremit 26 years after the Chernobyl accident. The (137)Cs activity concentrations were determined by gamma-ray spectrometry in the forest soil layers (OL, OF + OH and A horizons) separately. Based on 341 surface soil samples and 118 soil profiles, activity concentrations of (137)Cs in OL horizons varied between 0.25 ± 0.14 and 70 ± 1 Bq kg(-1), while the ranges of (137)Cs activity concentrations in OF + OH and A horizons were 13 ± 1-555 ± 3 Bq kg(-1) and 2 ± 1-253 ± 2 Bq kg(-1), respectively. Cesium-137 deposition in the study area was estimated to be in the range of 1-39 kBq m(-2) and a linear relationship between the deposition of (137)Cs and the altitude was observed. The distributions of (137)Cs activities in OL, OF + OH and A horizons throughout the region were mapped in detail. The highest (137)Cs activities were found in OF + OH horizons, with markedly lower (137)Cs activity in mineral horizons of soil profiles. It is observed that (137)Cs content of humus layer increases with the thickness of the humus layer for coniferous forest sites. The (137)Cs activity concentrations were higher than the recommended screening limits (150 Bq kg(-1)) at some of the investigated areas. The current activity concentration of top soil layers indicates that over many years since the initial deposition, (137)Cs activity is keeping still high in the organic horizons.

  20. Variations of 210Pb concentrations in surface air at Thessaloniki, Greece (40°N)

    NASA Astrophysics Data System (ADS)

    Ioannidou, A.; Kotsopoulou, E.; Karanatsiou, A.; Papastefanou, C.

    2012-04-01

    Atmospheric concentrations of 210Pb were measured over the year 2009 in ground level air at Thessaloniki, Northern Greece (40°62' N, 22°95'E). The mean activity concentrations of 210Pb in surface air have been found to be 671 ± 213 μBq m-3. The highest values of monthly atmospheric concentrations of 210Pb were observed in the autumn and the lowest in the spring period. The higher values of 210Pb during autumn were attributed to frequent inversion conditions of the surface layers, resulting in an enrichment of radon and its decay products in surface air. The lower values during the winter months might be due to the low emanation of radon from the frozen or snow-covered soil. The minima of 210Pb concentrations during spring might reflect on higher washout during this period, which results in less emanation of radon from saturated with water soil, resulting in less production of 210Pb near ground-level air. The relative high values during summer are probably due to the higher 222Rn exhalation from the ground and due to the higher air mixing within the troposphere, which has as a result to carry down to the surface layer 210Pb whose origin is older air masses which entered into the free troposphere.

  1. Sources and sinks of [sup 210]Pb in Concepcion Bay, Chile

    SciTech Connect

    Salamanca, Orrego, M.A.

    1993-01-01

    The sources and sinks of [sup 210]Pb to Concepcion Bay waters were evaluated to discern the relative importance of the main removal and supply mechanisms of this radionuclide to the waters of Concepcion Bay. The main inputs of [sup 210]Pb are the atmospheric supply and the advection of offshore upwelling waters. The atmospheric input was measured in precipitation using a collector and inventories of excess [sup 210]Pb in Rocuant and Raqui marsh sediments. The average atmospheric supply of [sup 210]Pb for Concepcion area is about 0.3 dpm cm[sup [minus]2] yr[sup [minus]1]. The advective input from upwelling varies from 0.6 [+-] 1.3 to 2.1 [+-] 2.0 dpm cm[sup [minus]2] yr[sup [minus]1]. [sup 210]Pb is removed efficiently from the water column as shelf water with high [sup 210]Pb content crosses the continental shelf off Concepcion Bay, with [sup 210]Pb/[sup 226]Ra activity ratios decreasing by a factor of 3 to 4 before reaching the interior of the bay. This is coincident with an increase of suspended matter concentration towards inside the bay. The main removal of [sup 210]Pb from Concepcion Bay waters is deposition in sediments. There is an increase of the [sup 210]Pb inventories toward the bay entrance excess (by a factor of 2) and outside the bay sediments (by a factor of 7). This pattern can be explained by an increase of mixing of sediments by the benthic infauna and enhanced removal of [sup 210]Pb from the water column by particles near the bay mouth. Mass balance calculations are included. The residence time of [sup 210]Pb with respect to removal from water column is estimated to be 17 to 43 days. The results of this research indicate that [sup 210]Pb and probably other similar particle-reactive contaminants (such as heavy metals) are retained and redistributed inside the bay by circulation, resuspension and biological mixing.

  2. Biological effects of {sup 137}CsCl injected in beagle dogs of different dogs

    SciTech Connect

    Nikula, K.J.; Boecker, B.B.; Griffith, W.C.

    1996-11-01

    The toxicity of {sup 137}Cs in the beagle dog was investigated at the Inhalation Toxicology Research Institute (ITRI) and Argonne National Laboratory (ANL) as part of programs to evaluate the biological effects of both radionuclides in atomic bomb fallout and internally deposited fission-product radionuclides. In the ITRI study, young adult dogs were exposed once by intravenous injection to a range of {sup 137}Cs concentrations; the results have recently been published. The purpose of the present report is to summarize the ANL study and to compare the results of the two studies. At ANL, 63 dogs in three age groups (15 juveniles, 142-151 days old; 38 young adults, 388-427 days old; and 10 middle-aged dogs, 1387-2060 days old) were given {sup 137}Cs intravenously at levels (61-162f MBq/kg) near those expected to be lethal within 30 days after injection. There were 17 control dogs from the same colony. Twenty-three of the dogs injected with {sup 137}Cs, including all middle-aged dogs, died within 52 days after injection due to hematopoietic cell damage resulting in severe pancytopenia that led to fatal hemorrhage and/or septicemia. The other significant early effect was damage to the germinal epithelium of the seminiferous tubules. The design of the ANL study revealed an age- and gender-related differential radiosensitivity for early effects. The middle-aged dogs died significantly earlier due to complications of hematological dyscrasia compared to the juvenile and young adult dogs, and the middle-aged females died significantly earlier than the middle-aged males. The most significant non-neoplastic late effects in the {sup 137}Cs-injected dogs from ANL and ITRI were atrophy of the germinal epithelium of seminiferous tubules with azoospermia, and a significant dose-dependent decrease in survival. The survival of the ANL dogs was decreased more than that of the ITRI dogs at similar radiation doses from {sup 137}Cs. 19 refs., 6 figs., 4 tabs.

  3. 135Cs/137Cs isotopic composition of environmental samples across Europe: Environmental transport and source term emission applications

    DOE PAGES

    Snow, Mathew S.; Snyder, Darin C.

    2015-11-02

    135Cs/137Cs isotopic analyses represent an important tool for studying the fate and transport of radiocesium in the environment; in this work the 135Cs/137Cs isotopic composition in environmental samples taken from across Europe is reported. Surface soil and vegetation samples from western Russia, Ukraine, Austria, and Hungary show consistent aged thermal fission product 135Cs/137Cs isotope ratios of 0.58 ± 0.01 (age corrected to 1/1/15), with the exception of one sample of soil-moss from Hungary which shows an elevated 135Cs/137Cs ratio of 1.78 ± 0.12. With the exception of the outlier sample from Hungary, surface soil/vegetation data are in quantitative agreement withmore » values previously reported for soils within the Chernobyl exclusion zone, suggesting that radiocesium at these locations is primarily composed of homogenous airborne deposition from Chernobyl. Seawater samples taken from the Irish Sea show 135Cs/137Cs isotope ratios of 1.22 ± 0.11 (age corrected to 1/1/15), suggesting aged thermal fission product Cs discharged from Sellafield. Furthermore, the differences in 135Cs/137Cs isotope ratios between Sellafield, Chernobyl, and global nuclear weapons testing fallout indicate that 135Cs/137Cs isotope ratios can be utilized to discriminate between and track radiocesium transport from different nuclear production source terms, including major emission sources in Europe.« less

  4. (135)Cs/(137)Cs isotopic composition of environmental samples across Europe: Environmental transport and source term emission applications.

    PubMed

    Snow, Mathew S; Snyder, Darin C

    2016-01-01

    (135)Cs/(137)Cs isotopic analyses represent an important tool for studying the fate and transport of radiocesium in the environment; in this work the (135)Cs/(137)Cs isotopic composition in environmental samples taken from across Europe is reported. Surface soil and vegetation samples from western Russia, Ukraine, Austria, and Hungary show consistent aged thermal fission product (135)Cs/(137)Cs isotope ratios of 0.58 ± 0.01 (age corrected to 1/1/15), with the exception of one sample of soil-moss from Hungary which shows an elevated (135)Cs/(137)Cs ratio of 1.78 ± 0.12. With the exception of the outlier sample from Hungary, surface soil/vegetation data are in quantitative agreement with values previously reported for soils within the Chernobyl exclusion zone, suggesting that radiocesium at these locations is primarily composed of homogenous airborne deposition from Chernobyl. Seawater samples taken from the Irish Sea show (135)Cs/(137)Cs isotope ratios of 1.22 ± 0.11 (age corrected to 1/1/15), suggesting aged thermal fission product Cs discharged from Sellafield. The differences in (135)Cs/(137)Cs isotope ratios between Sellafield, Chernobyl, and global nuclear weapons testing fallout indicate that (135)Cs/(137)Cs isotope ratios can be utilized to discriminate between and track radiocesium transport from different nuclear production source terms, including major emission sources in Europe.

  5. (135)Cs/(137)Cs isotopic composition of environmental samples across Europe: Environmental transport and source term emission applications.

    PubMed

    Snow, Mathew S; Snyder, Darin C

    2016-01-01

    (135)Cs/(137)Cs isotopic analyses represent an important tool for studying the fate and transport of radiocesium in the environment; in this work the (135)Cs/(137)Cs isotopic composition in environmental samples taken from across Europe is reported. Surface soil and vegetation samples from western Russia, Ukraine, Austria, and Hungary show consistent aged thermal fission product (135)Cs/(137)Cs isotope ratios of 0.58 ± 0.01 (age corrected to 1/1/15), with the exception of one sample of soil-moss from Hungary which shows an elevated (135)Cs/(137)Cs ratio of 1.78 ± 0.12. With the exception of the outlier sample from Hungary, surface soil/vegetation data are in quantitative agreement with values previously reported for soils within the Chernobyl exclusion zone, suggesting that radiocesium at these locations is primarily composed of homogenous airborne deposition from Chernobyl. Seawater samples taken from the Irish Sea show (135)Cs/(137)Cs isotope ratios of 1.22 ± 0.11 (age corrected to 1/1/15), suggesting aged thermal fission product Cs discharged from Sellafield. The differences in (135)Cs/(137)Cs isotope ratios between Sellafield, Chernobyl, and global nuclear weapons testing fallout indicate that (135)Cs/(137)Cs isotope ratios can be utilized to discriminate between and track radiocesium transport from different nuclear production source terms, including major emission sources in Europe. PMID:26540258

  6. Relationships Between Pb and 210Pb in Aerosol and Precipitation at a Semiremote Site in Northern Wisconsin

    NASA Astrophysics Data System (ADS)

    Talbot, R. W.; Andren, A. W.

    1983-08-01

    Measurements of Al, Pb, 210Pb, and 210Po in precipitation and aerosol were used to estimate wet and dry components of the atmospheric flux at a semiremote site in northern Wisconsin. Wet deposition was primarily responsible for removing airborne Pb, 210Pb, and 210Po, while dry deposition was also important for Al. Although Pb and 210Pb both exhibited a wet/total ratio of about 0.8, precipitation washout ratios for Pb and 210Pb suggested that 210Pb was washed from the atmosphere with greater efficiency than was Pb. This phenomenon was also illustrated by comparing the weighted mean annual specific activity in precipitation (976 pCi 210Pb mg-1 Pb) and in aerosol (476 pCi 210Pb mg-1 Pb) at this site between June 1979 and June 1980. By consideration of the apparent differential precipitation washout of Pb and 210Pb, a reasonable estimate of the atmospheric flux of Pb was obtained by using the mean Pb/210Pb ratio in aerosol and the 210Pb flux. The atmospheric flux to northern Wisconsin was estimated to be 0.8 μg cm-2 yr-1 for Pb and 0.70 pCi cm-2 yr-1 for 210Pb.

  7. Concentrations of (137)Cs in summer pasture plants that reindeer feed on in the reindeer management area of Finland.

    PubMed

    Anttila, Annukka; Leppänen, Ari-Pekka; Rissanen, Kristiina; Ylipieti, Jarkko

    2011-07-01

    Samples of summer pasture plants that reindeer feed on were collected in order to study (137)Cs concentrations in different plant species and in species nested in certain site types, and to study the regional distribution of (137)Cs in the Finnish reindeer management area. Plant species were categorized by the site types of mineral soil forest (xeric heath forest and mesic heath forest) and peatland. A third category called 'other plant species' included plants with various site types, poorly determined species and species with poor statistics. The (137)Cs concentrations in different site types differed significantly. The mean (137)Cs concentrations of the whole reindeer management area in the xeric heath forest plant species was 44 ± 27 Bq/kg dw, in the mesic heath forest plant species 75 ± 59 Bq/kg dw and in the peatland plant species 219 ± 150 Bq/kg dw. The peatland species uptake (137)Cs more efficiently than plant species of mineral soil forests. A particularly efficient collector of (137)Cs was Trichophorum sp. It is suggested that Trichophorum sp. could be used as an indicator species for reindeer summer fodder plants. The highest concentrations of (137)Cs were found in Southern Lapland and the lowest in Northern Lapland. Today, the concentrations of (137)Cs in summer pasture plants that reindeer feed on in Finland are at such a level that there is no need to avoid any plant species. In the case of future nuclear fallout, reindeer grazing in peatlands would increase concentrations of (137)Cs in reindeer meat.

  8. Modeling (137)Cs bioaccumulation in the salmon-resident killer whale food web of the Northeastern Pacific following the Fukushima Nuclear Accident.

    PubMed

    Alava, Juan José; Gobas, Frank A P C

    2016-02-15

    To track the long term bioaccumulation of (137)Cs in marine organisms off the Pacific Northwest coast of Canada, we developed a time dependent bioaccumulation model for (137)Cs in a marine mammalian food web that included fish-eating resident killer whales. The model outcomes show that (137)Cs can be expected to gradually bioaccumulate in the food web over time as demonstrated by the increase of the apparent trophic magnification factor of (137)Cs, ranging from 0.76 after 1 month of exposure to 2.0 following 30 years of exposure. (137)Cs bioaccumulation is driven by relatively rapid dietary uptake rates, moderate depuration rates in lower trophic level organisms and slow elimination rates in high trophic level organisms. Model estimates of the (137)Cs activity in species of the food web, based on current measurements and forecasts of (137)Cs activities in oceanic waters and sediments off the Canadian Pacific Northwest, indicate that the long term (137)Cs activities in fish species including Pacific herring, wild Pacific salmon, sablefish and halibut will remain well below the current (137)Cs-Canada Action Level for consumption (1000 Bq/kg) following a nuclear emergency. Killer whales and Pacific salmon are expected to exhibit the largest long term (137)Cs activities and may be good sentinels for monitoring (137)Cs in the region. Assessment of the long term consequences of (137)Cs releases from the Fukushima aftermath should consider the extent of ecological magnification in addition to ocean dilution. PMID:26657356

  9. Modeling (137)Cs bioaccumulation in the salmon-resident killer whale food web of the Northeastern Pacific following the Fukushima Nuclear Accident.

    PubMed

    Alava, Juan José; Gobas, Frank A P C

    2016-02-15

    To track the long term bioaccumulation of (137)Cs in marine organisms off the Pacific Northwest coast of Canada, we developed a time dependent bioaccumulation model for (137)Cs in a marine mammalian food web that included fish-eating resident killer whales. The model outcomes show that (137)Cs can be expected to gradually bioaccumulate in the food web over time as demonstrated by the increase of the apparent trophic magnification factor of (137)Cs, ranging from 0.76 after 1 month of exposure to 2.0 following 30 years of exposure. (137)Cs bioaccumulation is driven by relatively rapid dietary uptake rates, moderate depuration rates in lower trophic level organisms and slow elimination rates in high trophic level organisms. Model estimates of the (137)Cs activity in species of the food web, based on current measurements and forecasts of (137)Cs activities in oceanic waters and sediments off the Canadian Pacific Northwest, indicate that the long term (137)Cs activities in fish species including Pacific herring, wild Pacific salmon, sablefish and halibut will remain well below the current (137)Cs-Canada Action Level for consumption (1000 Bq/kg) following a nuclear emergency. Killer whales and Pacific salmon are expected to exhibit the largest long term (137)Cs activities and may be good sentinels for monitoring (137)Cs in the region. Assessment of the long term consequences of (137)Cs releases from the Fukushima aftermath should consider the extent of ecological magnification in addition to ocean dilution.

  10. Determination of (210)Pb and (210)Po in water using the extractive scintillation cocktail Polex™.

    PubMed

    Landstetter, Claudia; Hiegesberger, Bernd; Sinojmeri, Merita; Katzlberger, Christian

    2014-11-01

    Method validation was performed to achieve the accreditation for our determination method of (210)Pb and (210)Po in water. A Pb(NO3)2 carrier is added to the sample and lead is precipitated with Na2SxH2O. (210)Po is co-precipitated and the extractive scintillation cocktail Polex(™) is used to determine (210)Po and (210)Pb. Uranium is also extracted by Polex(™). It can be removed by washing the precipitate with 1% HNO3. The ingrowth of (210)Pb from (222)Rn during transportation time must be calculated. It has to be subtracted from the original (210)Pb in the sample and taken into account for the calculation of the lower limit of detection.

  11. Determination of (210)Pb and (210)Po in water using the extractive scintillation cocktail Polex™.

    PubMed

    Landstetter, Claudia; Hiegesberger, Bernd; Sinojmeri, Merita; Katzlberger, Christian

    2014-11-01

    Method validation was performed to achieve the accreditation for our determination method of (210)Pb and (210)Po in water. A Pb(NO3)2 carrier is added to the sample and lead is precipitated with Na2SxH2O. (210)Po is co-precipitated and the extractive scintillation cocktail Polex(™) is used to determine (210)Po and (210)Pb. Uranium is also extracted by Polex(™). It can be removed by washing the precipitate with 1% HNO3. The ingrowth of (210)Pb from (222)Rn during transportation time must be calculated. It has to be subtracted from the original (210)Pb in the sample and taken into account for the calculation of the lower limit of detection. PMID:24816175

  12. Accumulation of /sup 137/Cs in commercial fish of the Belyarsk nuclear power station cooling supply

    SciTech Connect

    Trapeznikova, V.N.; Kulikov, N.V.; Trapeznikov, A.V.

    1984-07-01

    Results are presented of a comparative study of the accumulation of /sup 137/Cs in basic species of commercial fish of the Beloyarsk reservoir which is used as the cooling supply for the Beloyarsk nuclear power station. Possible reasons for interspecies differences in accumulation of the radionuclide are indicated, and the increased accumulation of /sup 137/Cs by free-living fish in the zone of heated water effluent from the station and the reduced accumulation of the emitter in carp, which are cultivated on artificial food in cages, are noted. Levels of the content of the radionuclide are compared in roach and farm carp from the cooling supplies of the Beloyarsk station and the Reftinsk power plant in the Urals.

  13. Marine dispersion assessment of 137Cs released from the Fukushima nuclear accident.

    PubMed

    Min, Byung-Il; Periáñez, Raul; Kim, In-Gyu; Suh, Kyung-Suk

    2013-07-15

    Radionuclides were released into the atmosphere and ocean due to an accident in the Fukushima Daiichi Nuclear Power Plant (NPP) in March 2011. Numerical simulations were carried out to evaluate the distribution of (137)Cs in the ocean considering both direct releases to the sea and deposition from the atmosphere as source terms. A significant amount of atmospheric deposition occurred on the sea surface in the northeast direction from the Fukushima NPP, due to westerly winds and precipitations on March 15-31, 2011. In a previous study using local scale modeling, no significant differences in resulting (137)Cs patterns in water and sediments with and without atmospheric deposition were found. However, this new research, on a regional scale, has pointed out meaningful differences in seabed sediment radionuclide concentrations in the Fukushima northeast area with and without atmospheric deposition.

  14. Ecological half-life of 137Cs in lichens in an alpine region.

    PubMed

    Machart, Peter; Hofmann, Werner; Türk, Roman; Steger, Ferdinand

    2007-01-01

    About 17 years after the Chernobyl accident, lichen samples were collected in an alpine region in Austria (Bad Gastein), which was heavily contaminated by the Chernobyl fallout. Measured 137Cs activity concentrations in selected lichens (Cetraria islandica, Cetraria cucullata, and Cladonia arbuscula) ranged from 100 to 1100 Bq kg(-1) dry weight, depending on lichen species and sampling site. Ecological half-lives for 137Cs in different lichen samples, obtained by comparison with earlier measurements of the same lichen species at the same site, ranged from 2 to 6 years, with average values between 3 and 4 years. Comparison with earlier studies indicated that ecological half-lives hardly changed during the last 10 years, suggesting that ecological clearance mechanisms (e.g. washout or soil transfer) did not vary substantially at the selected sampling area.

  15. {sup 137}Cs content in the fruit bodies of various Tuber species

    SciTech Connect

    Lorenzelli, R.; Lamma, A.; Zambonelli, A.; Serra, F.

    1996-12-01

    In this research, the concentration of {sup 137}Cs in the fruit bodies of the Tuber species T. magnatum Pico, T. borchii Vitt., T. aestivum Vitt., and T. excavatum Vitt. collected in three different regions of Italy was determined. The values obtained have been compared to the soil concentration of {sup 137}Cs, and the transfer factor was determined. The radiocesium content of the examined fruit bodies ranged from 2.5 Bq kg{sup {minus}1} to 33.3 Bq kg{sup {minus}1} fresh weight; the median transfer factor values of the four species ranged between 0.06 and 0.6. Our findings indicate that the radiocesium level in truffles from these regions of Italy is generally low, and, thus, their consumption is not of radiological concern. The results may suggest certain hypotheses as to the mechanisms involved in radiocesium uptake in these fungi. 19 refs., 1 fig., 4 tabs.

  16. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site.

    PubMed

    Robison, William L; Conrado, Cynthia L; Bogen, Kenneth T; Stoker, A Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 (137Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137Cs and 90Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137Cs and 90Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137Cs/90Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137Cs/90Sr ratios in soil in 1987 relative to the 137Cs/90Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on the ELH for 90Sr

  17. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site.

    PubMed

    Robison, William L; Conrado, Cynthia L; Bogen, Kenneth T; Stoker, A Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 (137Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137Cs and 90Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137Cs and 90Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137Cs/90Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137Cs/90Sr ratios in soil in 1987 relative to the 137Cs/90Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on the ELH for 90Sr

  18. [Regularities of changes in 137Cs content in milk in the long term after the Chernobyl nuclear reactor accident].

    PubMed

    Fesenko, S V; Pakhomov, A Iu; Pasternak, A D; Goriainov, V A; Fesenko, G A; Panov, A V

    2004-01-01

    Regularities of changes in 137Cs content in cattle milk in the long term after the Chernobyl accident have been analyzed. Contamination levels of haylands and pastures, soil properties, specific features of agricultural production and time after the fallout play a crucial role in 137Cs concentration changes in animal products. Trends have been studied that reflect the influence of these factors and their significance assessed. The half-life periods of 137Cs decay in milk vary over the period of 1994 to 2000 between 7.1 and 14.8 years and approach similar periods calculated for the long term after global radioactive fallout from nuclear weapons tests.

  19. Hindcast of 137Cs in the North Pacific Ocean from 1945 to 2013 by eddy-resolving ROMS

    NASA Astrophysics Data System (ADS)

    Tsubono, Takaki; Misumi, Kazuhiro; Tsumune, Daisuke; Aoyama, Michio; Hirose, Katsumi

    2014-05-01

    We conducted the hindcast of 137Cs activity in the North Pacific Ocean from 1945 to 2013, before and after the Fukushima Dai-ichi Nuclear Power Plant (1F NPP) accident. We used the Regional Ocean Model System (ROMS) with high resolution (1/12°-1/4° in horizontal, 45 levels in vertical), of which domain was the North Pacific Ocean. This model employed the CORE normal year forcing data for a driving forcing and the 50 years averaged SODA data for boundary conditions. The reconstructed global fallout due to atmospheric nuclear weapons' tests and Chernobyl accident was employed for atmospheric input flux of 137Cs from 1945 to 2013. After the accident, the atmospheric deposition and direct release of 137Cs from 1F NPP were also employed for input condition. Five ensemble calculations of 137Cs activity were conducted by moving the start period of the input flux for one year. The simulated vertical distributions of 137Cs activity along 165°E represented the overall patterns of the observed 137Cs activity before (in 2002) and after (in 2012) the accident, in particular the high activity core of the 137Cs around North Pacific Subtropical Mode Water and Central Mode Water, indicating that this model can represent the subduction process and formation of the Mode Waters. The simulated 137Cs activity in the surface ranged from 0.75 to 2.Bq m-3 in the north of Kuroshio Extension in 2011 before the accident. The main body of high 137Cs activity water from 1F NPP was transported in the northern part of Kuroshio Extension after the accident. In Sep. 2012, 18 months after the accident, the main body of high 137Cs activity water (≥ 10 Bq m-3) was located at around 40°N, 150°E-160°W. The water over 10 Bq m-3 of 137Cs activity was not detected in surface layer, but in the layer of σθ=25.8-26.2 at two small areas (44°N, 180°W-165°W and 48°N, 160°W-140°W). This model simulation suggests that the main body of high 137Cs activity water from 1F NPP has never reached the

  20. [Regularities of changes in 137Cs content in milk in the long term after the Chernobyl nuclear reactor accident].

    PubMed

    Fesenko, S V; Pakhomov, A Iu; Pasternak, A D; Goriainov, V A; Fesenko, G A; Panov, A V

    2004-01-01

    Regularities of changes in 137Cs content in cattle milk in the long term after the Chernobyl accident have been analyzed. Contamination levels of haylands and pastures, soil properties, specific features of agricultural production and time after the fallout play a crucial role in 137Cs concentration changes in animal products. Trends have been studied that reflect the influence of these factors and their significance assessed. The half-life periods of 137Cs decay in milk vary over the period of 1994 to 2000 between 7.1 and 14.8 years and approach similar periods calculated for the long term after global radioactive fallout from nuclear weapons tests. PMID:15287266

  1. Assessing soil redistribution in a complex karst catchment using fallout 137Cs and GIS

    NASA Astrophysics Data System (ADS)

    Navas, A.; López-Vicente, M.; Gaspar, L.; Machín, J.

    2013-08-01

    Caesium-137 derived from nuclear testing in the past century has been widely used as a sediment tracer of soil redistribution, providing information on medium term (40-50 years) erosion rates. To date, most studies have focused on individual fields of limited extent, but estimated rates and patterns of soil redistribution require upscaling to catchment level. An attempt to assess soil redistribution processes with strong geomorphic control on complex terrain, such as an internally drained karst catchment, is presented in this work. A comprehensive geomorphological survey of the Estanya Lake catchment (Spanish Pyrenees) enabled the main geomorphic elements to be identified with a grid resolution of 5 × 5 m, which was the basis for the terrain analyses. A detailed DEM was constructed and improved after field identification of the drainage system and point measures on gentle slopes with Total Topographic Station. A 100 × 100 m sampling grid was established to derive point data of 137Cs inventories across the catchment. Geostatistical interpolation of point samples of 137Cs inventories in soil was carried out to identify and assess the areas of sediment gain and loss by comparing with 137Cs reference inventories. Profile activity models were used to calibrate 137Cs data and to derive estimates of soil redistribution. GIS was used to provide spatially distributed erosion and deposition rates in the landscape for the whole catchment. The median values of soil erosion and deposition of 4.7 and 3.1 Mg ha- 1 year- 1, respectively, showed a large variability and reveal coupling between erosional and depositional forms in the catchment. The highest erosion and deposition rates were found in cultivated fields at the southern sector of the catchment. The spatial analysis of the results supports the importance of taking into account geomorphological features in karst catchments as relevant controlling factors in soil redistribution processes.

  2. The inhibitory effects of potassium chloride versus potassium silicate application on (137)Cs uptake by rice.

    PubMed

    Fujimura, Shigeto; Yoshioka, Kunio; Ota, Takeshi; Ishikawa, Tetsuya; Sato, Makoto; Satou, Mutsuto

    2016-03-01

    After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company on 11 March 2011, potassium fertilizer was applied to agricultural fields in the southern Tohoku and northern Kanto regions of Japan to reduce the uptake of radiocesium by crops. In this study, we examined the effects of two types of potassium fertilizers, potassium chloride (a readily available potassium fertilizer) and potassium silicate (a slow-release potassium fertilizer), as well as a split application of potassium, on the accumulation of (137)Cs by rice plants in two pot experiments. The (137)Cs concentrations in the brown rice and in the above-ground plants were significantly lower after potassium chloride application than after potassium silicate application. The potassium ion (K(+)) concentrations in soil solutions sampled 9 and 21 d after transplanting were significantly higher for the potassium chloride application than for the potassium silicate application. The K(+) concentrations in soil solutions observed in the application of potassium silicate were similar to those in the treatment when no potassium was applied. This finding indicates that the application of potassium silicate did not sufficiently increase the available K(+) for rice plants in the soil, which led to a greater uptake of (137)Cs after the potassium silicate application than after the application of potassium chloride. The (137)Cs concentration in brown rice was higher in the split application of potassium fertilizer with the second application at the full heading stage than that without split application and the split application with the second application before heading. PMID:26773513

  3. Evaluation of the 2014 EC measurement comparison on (137)Cs in air filters.

    PubMed

    Máté, B; Sobiech-Matura, K; Altzitzoglou, T

    2016-03-01

    In 2014, the Joint Research Centre organised an interlaboratory comparison of (137)Cs measurement in air filters. This paper describes the context of the European measurement comparisons, as well as the technical implementation. Furthermore, sample treatment and measurements performed by participating laboratories are discussed and finally the evaluation of comparison results is presented. The intercomparison results are such that 71 out of the 76 laboratories (i.e. 93.4%) reported values within ±33% range of the reference value.

  4. Chernobyl {sup 137}Cs used to determine sediment accretion rates at selected northern European coastal wetlands

    SciTech Connect

    Callaway, J.C.; DeLaune, R.D.; Patrick, W.H. Jr.

    1996-05-01

    Sediment cores were collected form five coastal wetlands along the North Sea (England and Netherlands) and Baltic Sea (Poland). {sup 137}Cs dating was used to assess sediment accretion rates, including rates based on the {sup 137}Cs peak from the 1986 accident at Chernobyl. Peaks form the Chernobyl fallout were found in cores from the Oder and Vistula Rivers in Poland, from the Eastern Scheldt in the Netherlands, and in one of the two cores from Stiffkey Marsh, UK. No evidence of Chernobyl fallout was found in cores from Dengie Marsh, UK. The Chernobyl {sup 137}Cs peak serves as an excellent marker for short-term accretion rates because of its high activity. Vertical accretion rates (cm yr{sup {minus}1}) based on 1963 and 1986 peaks were similar at most sites; differences may be due to large inputs of sediment from storms or recent accumulation of organic matter. Large differences in sediment characteristics and accretion rates were found between samples from Poland and western Europe. Vertical accretion rates over the period 1963-1986 ranged from 0.26 to 0.85 cm{sup {minus}1} and from 0.30 to 1.90 cm yr{sup {minus}1} over the 1986-1991 period. Vertical accretion rates for the period these sites are in imminent danger of excessive flooding. The Chernobyl {sup 137}Cs peak will be especially useful for studies of short-term (i.e. very recent) sedimentation in the near future and for comparisons of sediment processes over different time scales. 33 refs., 4 figs., 4 tabs.

  5. Using 137Cs to quantify the sediment delivery ratio in a small watershed.

    PubMed

    Li, Mian; Yao, Wenyi; Li, Zhanbin; Liu, Puling; Yang, Er; Shen, Zhenzhou

    2012-01-01

    Understanding the sediment delivery ratio (SDR) is important in controlling sediments for the sustainable development of natural resources and in the design of the construction such as dams and reservoirs. The purpose of this investigation is to determine the SDR by the (137)Cs tracing method in a small watershed in the Sichuan Hilly Basin of China. In the study watershed, different land plots are divided according to the land use type, and 97 sampling sites were selected from these plots. The results show that the average net soil loss rates from the forest land and sloping cultivated land are 1759 and 4468t/km(2)a, respectively. No (137)Cs was detectable on the bare rock surfaces and previous work showed that the erosion rate from the bare rock area was 14,260t/km(2)a. In the depositional zone, the sedimentation rates in the Caoto (a kind of cultivated land located at the foot of hills) and paddy field are 3113 and 3562t/km(2)a, respectively. Combining the area of each land use in the small watershed, the SDR of 0.40 is obtained in the past four decades. The (137)Cs technique was shown to provide an effective and rapid means of estimating the SDR within the small watershed.

  6. Release, deposition and elimination of radiocesium ((137)Cs) in the terrestrial environment.

    PubMed

    Ashraf, Muhammad Aqeel; Khan, Ayesha Masood; Ahmad, Mushtaq; Akib, Shatirah; Balkhair, Khaled S; Bakar, Nor Kartini Abu

    2014-12-01

    Radionuclide contamination in terrestrial ecosystems has reached a dangerous level. The major artificial radionuclide present in the environment is (137)Cs, which is released as a result of weapon production related to atomic projects, accidental explosions of nuclear power plants and other sources, such as reactors, evaporation ponds, liquid storage tanks, and burial grounds. The release of potentially hazardous radionuclides (radiocesium) in recent years has provided the opportunity to conduct multidisciplinary studies on their fate and transport. Radiocesium's high fission yield and ease of detection made it a prime candidate for early radio-ecological investigations. The facility setting provides a diverse background for the improved understanding of various factors that contribute toward the fate and transfer of radionuclides in the terrestrial ecosystem. In this review, we summarize the significant environmental radiocesium transfer factors to determine the damaging effects of radiocesium on terrestrial ecosystem. It has been found that (137)Cs can trace the transport of other radionuclides that have a high affinity for binding to soil particles (silts and clays). Possible remedial methods are also discussed for contaminated terrestrial systems. This review will serve as a guideline for future studies of the fate and transport of (137)Cs in terrestrial environments in the wake of the Fukushima Nuclear Power Plant disaster in 2011. PMID:24804829

  7. Uptake of 137Cs in vegetable crops grown on a contaminated lakebed.

    PubMed

    Seel, J F; Whicker, F W; Adriano, D C

    1995-06-01

    Mean concentrations and plant:soil concentration ratios of 137Cs were determined for six vegetable crops grown on an exposed, contaminated lakebed of a former reactor cooling reservoir in South Carolina. Each crop species was grown with or without potassium fertilizer. Selected crops were also irrigated with either reservoir water or groundwater. Subsamples of crops were prepared for human consumption before analysis to determine the extent of any loss. Plant:soil concentration ratios (dry basis) ranged from 0.22 to 6.82, values which were substantially higher than those used in generic assessment models. While there was no statistically significant effect of irrigation source or culinary preparation, the effect of potassium-fertilizer was dramatic. In many cases, concentrations of 137Cs in those plants receiving potassium were less than half of the concentrations in plants that did not receive potassium. Significant differences among species and plant parts for 137Cs concentrations were observed. Dose/risk calculations for the ingestion of these vegetables by a hypothetical 30-y resident indicates the possibility of a lifetime fatal cancer risk well-above the U.S. Environmental Protection Agency's regulatory guideline of 10(-4).

  8. Spatial distribution of fallout 137Cs in the coastal marine environment of India.

    PubMed

    Jha, S K; Gothankar, S S; Sartandel, S; Pote, M B; Hemalatha, P; Rajan, M P; Vidyasagar, D; Indumati, S P; Shrivastava, R; Puranik, V D

    2012-11-01

    The data on the fallout (137)Cs in the coastal marine environment assume significance in view of massive expansion of nuclear power plants in the Asia-Pacific region and to fulfill the benchmark study required to evaluate the possible impact of the Fukushima radioactive releases in the Asia-Pacific region. Measurements of (137)Cs in sea water, along with salinity and temperature, were carried out at 30 locations covering the coastal area of the Arabian Sea and the Bay of Bengal. For the present study the Indian coastal area is divided in three different regions. The (137)Cs concentration in sea water of the entire Indian coastal region varies from 0.30 to 1.25 Bq m(-3). The data obtained in the present study was compared with the North Indian Ocean data and it was observed that there is a 33% decrease in the Arabian Sea (region I), 50% in the high rainfall coastal area (region II) and 24% in the Bay of Bengal (region III).

  9. Release, deposition and elimination of radiocesium ((137)Cs) in the terrestrial environment.

    PubMed

    Ashraf, Muhammad Aqeel; Khan, Ayesha Masood; Ahmad, Mushtaq; Akib, Shatirah; Balkhair, Khaled S; Bakar, Nor Kartini Abu

    2014-12-01

    Radionuclide contamination in terrestrial ecosystems has reached a dangerous level. The major artificial radionuclide present in the environment is (137)Cs, which is released as a result of weapon production related to atomic projects, accidental explosions of nuclear power plants and other sources, such as reactors, evaporation ponds, liquid storage tanks, and burial grounds. The release of potentially hazardous radionuclides (radiocesium) in recent years has provided the opportunity to conduct multidisciplinary studies on their fate and transport. Radiocesium's high fission yield and ease of detection made it a prime candidate for early radio-ecological investigations. The facility setting provides a diverse background for the improved understanding of various factors that contribute toward the fate and transfer of radionuclides in the terrestrial ecosystem. In this review, we summarize the significant environmental radiocesium transfer factors to determine the damaging effects of radiocesium on terrestrial ecosystem. It has been found that (137)Cs can trace the transport of other radionuclides that have a high affinity for binding to soil particles (silts and clays). Possible remedial methods are also discussed for contaminated terrestrial systems. This review will serve as a guideline for future studies of the fate and transport of (137)Cs in terrestrial environments in the wake of the Fukushima Nuclear Power Plant disaster in 2011.

  10. Evidence for diffusive redistribution of sup 210 Pb in lake sediments

    SciTech Connect

    Benoit, G.; Hemond, H.F. )

    1991-07-01

    {sup 210}Pb, {sup 210}Po, and ancillary geochemical parameters were measured in the sediments and pore waters of a lake with seasonally anoxic bottom waters. Substantial release of radionuclides to the water column has been documented at this site. Solid phase {sup 210}Pb profiles do not match the expected input history, suggesting that the radionuclide may be undergoing redistribution. High levels of the radionuclides were measured in pore waters, consistent with partition coefficients in the range from 10{sup 3} to 10{sup 4}. The high pore water activities, apparent redistribution pattern, and the documented release of {sup 210}Pb from these sediments to the water column, all point to the possible importance of pore water diffusion as a {sup 210}Pb transport mechanism. The distribution of {sup 210}Pb in these sediments was successfully modeled using a combination of sediment burial and pore water diffusion without the need to invoke particle reworking. Theoretical analysis supports the idea that in some cases large dating errors can result if diffusive redistribution of {sup 210}Pb is neglected.

  11. Aging effect of 137Cs obtained from 137Cs in the Kanto loam layer from the Fukushima nuclear power plant accident and in the Nishiyama loam layer from the Nagasaki A-bomb explosion.

    PubMed

    Ohta, Tomoko; Mahara, Yasunori; Kubota, Takumi; Igarashi, Toshifumi

    2013-01-01

    We measured (134)Cs and (137)Cs in the surface soil of the Kanto loam in the eastern Tokyo metropolitan area and the Nishiyama loam in Nagasaki, Japan. The observed (137)Cs deposition in the Kanto loam from the Fukushima nuclear power plant (NPP) accident ranged from 4.0 to 77 kBq m(-2), which corresponds to 0.3-5 times of that in the Nishiyama loam. The (137)Cs retardation factor in the Kanto loam obtained seven months after the Fukusima NPP accident and in the Nishiyama loam after 36 and 38 years from the detonation of the Pu atomic bomb (A-bomb) ranged from 180 to 260 and 2000 to 10,000, respectively. This difference in the retardation factors is attributed to an aging effect that corresponds to seven months and 36 to 38 years after the deposition of (137)Cs occurred on the soil minerals. PMID:24107558

  12. Aging effect of 137Cs obtained from 137Cs in the Kanto loam layer from the Fukushima nuclear power plant accident and in the Nishiyama loam layer from the Nagasaki A-bomb explosion.

    PubMed

    Ohta, Tomoko; Mahara, Yasunori; Kubota, Takumi; Igarashi, Toshifumi

    2013-01-01

    We measured (134)Cs and (137)Cs in the surface soil of the Kanto loam in the eastern Tokyo metropolitan area and the Nishiyama loam in Nagasaki, Japan. The observed (137)Cs deposition in the Kanto loam from the Fukushima nuclear power plant (NPP) accident ranged from 4.0 to 77 kBq m(-2), which corresponds to 0.3-5 times of that in the Nishiyama loam. The (137)Cs retardation factor in the Kanto loam obtained seven months after the Fukusima NPP accident and in the Nishiyama loam after 36 and 38 years from the detonation of the Pu atomic bomb (A-bomb) ranged from 180 to 260 and 2000 to 10,000, respectively. This difference in the retardation factors is attributed to an aging effect that corresponds to seven months and 36 to 38 years after the deposition of (137)Cs occurred on the soil minerals.

  13. (137)Cs distributions in soil and trees in forest ecosystems after the radioactive fallout - Comparison study between southern Finland and Fukushima, Japan.

    PubMed

    Pumpanen, Jukka; Ohashi, Mizue; Endo, Izuki; Hari, Pertti; Bäck, Jaana; Kulmala, Markku; Ohte, Nobuhito

    2016-09-01

    The nuclear accidents at Chernobyl and Fukushima released large amounts of (137)Cs radionuclides into the atmosphere which spread over large forest areas. We compared the (137)Cs concentration distribution in different parts of two coniferous forest ecosystems (needle litter, stems and at different depths in the soil) over short and long term periods in Finland and Japan. We also estimated the change in (137)Cs activity concentrations in needle and soil between 1995 and 2013 in Southern Finland based on the back-calculated (137)Cs activity concentrations. We hypothesized that if the (137)Cs activity concentrations measured in 1995 and 2013 showed a similar decline in concentration, the (137)Cs activity concentration in the ecosystem was already stable in 1995. But if not, the (137)Cs activity concentrations were still changing in 2013. Our results showed that the vertical distribution of the (137)Cs fallout in the soil was similar in Hyytiälä and Fukushima. The highest (137)Cs concentrations were observed in the uppermost surface layers of the soil, and they decreased exponentially deeper in the soil. We also observed that (137)Cs activity concentrations estimated from the samples in 1995 and 2013 in Finland showed different behavior in the surface soil layers compared to the deep soil layer. These results suggested that the (137)Cs nuclei were still mobile in the surface soil layers 27 years after the accident. Our results further indicated that, in the aboveground parts of the trees, the (137)Cs concentrations were much closer to steady-state when compared to those of the surface soil layers based on the estimated declining rates of (137)Cs concentration activity in needles which were similar in 1995 and 2013. Despite its mobility and active role in the metabolism of trees, the (137)Cs remains in the structure of the trees for decades, and there is not much exchange of (137)Cs between the heartwood and surface layers of the stem. PMID:27158060

  14. (137)Cs distributions in soil and trees in forest ecosystems after the radioactive fallout - Comparison study between southern Finland and Fukushima, Japan.

    PubMed

    Pumpanen, Jukka; Ohashi, Mizue; Endo, Izuki; Hari, Pertti; Bäck, Jaana; Kulmala, Markku; Ohte, Nobuhito

    2016-09-01

    The nuclear accidents at Chernobyl and Fukushima released large amounts of (137)Cs radionuclides into the atmosphere which spread over large forest areas. We compared the (137)Cs concentration distribution in different parts of two coniferous forest ecosystems (needle litter, stems and at different depths in the soil) over short and long term periods in Finland and Japan. We also estimated the change in (137)Cs activity concentrations in needle and soil between 1995 and 2013 in Southern Finland based on the back-calculated (137)Cs activity concentrations. We hypothesized that if the (137)Cs activity concentrations measured in 1995 and 2013 showed a similar decline in concentration, the (137)Cs activity concentration in the ecosystem was already stable in 1995. But if not, the (137)Cs activity concentrations were still changing in 2013. Our results showed that the vertical distribution of the (137)Cs fallout in the soil was similar in Hyytiälä and Fukushima. The highest (137)Cs concentrations were observed in the uppermost surface layers of the soil, and they decreased exponentially deeper in the soil. We also observed that (137)Cs activity concentrations estimated from the samples in 1995 and 2013 in Finland showed different behavior in the surface soil layers compared to the deep soil layer. These results suggested that the (137)Cs nuclei were still mobile in the surface soil layers 27 years after the accident. Our results further indicated that, in the aboveground parts of the trees, the (137)Cs concentrations were much closer to steady-state when compared to those of the surface soil layers based on the estimated declining rates of (137)Cs concentration activity in needles which were similar in 1995 and 2013. Despite its mobility and active role in the metabolism of trees, the (137)Cs remains in the structure of the trees for decades, and there is not much exchange of (137)Cs between the heartwood and surface layers of the stem.

  15. Modification of (137)Cs transfer to rape (Brassica napus L.) phytomass under the influence of soil microorganisms.

    PubMed

    Pareniuk, O; Shavanova, K; Laceby, J P; Illienko, V; Tytova, L; Levchuk, S; Gudkov, I; Nanba, K

    2015-11-01

    After nuclear accidents, such as those experienced in Chernobyl and Fukushima, microorganisms may help purify contaminated soils by changing the mobility of radionuclides and their availability for plants by altering the physical and chemical properties of the substrate. Here, using model experiments with quartz sand as a substrate we investigate the influence of microorganisms on (137)Cs transfer from substrate to plants. The highest transition of (137)Cs from substrate to plants (50% increase compared to the control) was observed after Brassica napus L. seeds were inoculated by Azotobacter chroococcum. The best results for reducing the accumulation of (137)Cs radionuclides (30% less) were noted after the inoculation by Burkholderia sp.. Furthermore, Bacillus megaterium demonstrated an increased ability to accumulate (137)Cs. This research improves our prediction of the behavior of radionuclides in soil and may contribute towards new, microbiological countermeasures for soil remediation following nuclear accidents. PMID:26210686

  16. Field Deployment of Illite Clay as an InSitu Method for Remediating 137Cs-Contaminated Wetlands

    SciTech Connect

    Kaplan, D.I.

    2003-01-29

    The research reported herein centered on a field deployment of the in situ remediation method with the goal of learning if the clay amendments reduce the biological availability of 137Cs in contaminated wetlands.

  17. Distribution of local 137Cs anomalies on the seafloor near the Fukushima Dai-ichi Nuclear Power Plant.

    PubMed

    Thornton, Blair; Ohnishi, Seiki; Ura, Tamaki; Odano, Naoteru; Sasaki, Shun; Fujita, Tsuneo; Watanabe, Tomowo; Nakata, Kaoru; Ono, Tsuneo; Ambe, Daisuke

    2013-09-15

    An estimated 3.5±0.7×10(15) Bq of (137)Cs is thought to have been discharged into the ocean following the melt down at Fukushima Dai-ichi Nuclear Power Plant (F1NPP). While efforts have been made to monitor seafloor radiation levels, the sampling techniques used cannot capture the continuous distribution of radionuclides. In this work, we apply in situ measurement techniques using a towed gamma ray spectrometer to map the continuous distribution of (137)Cs on the seafloor within 20 km of the F1NPP. The results reveal the existence of local (137)Cs anomalies, with levels of (137)Cs an order of magnitude higher than the surrounding seafloors. The sizes of the anomalies mapped in this work range from a few meters to a few hundreds of meters in length, and it is demonstrated that the distribution of these anomalies is strongly influenced by meter scale features of the terrain.

  18. Extreme 210Pb-226Ra Disequilibria Observed in arc Lavas: Implications for the Time Scales of Magma Degassing

    NASA Astrophysics Data System (ADS)

    Turner, S.; Black, S.

    2003-12-01

    We have undertaken α -counting measurements of 210Pb activity in 39 arc lavas previously analysed by TIMS for U-Th-Ra and, more recently, U-Pa disequilibria from the Lesser Antilles, Tonga, Vanuatu, Philippines, Marianas, Sunda, Kamchatka and the Aleutians. The lavas were erupted between 1953 and 1999 and show extreme variation in 210Pb -226Ra disequilibria with age corrected (210Pb /226Ra) activity ratios ranging from 0.36 to 3.14. In detail, the majority (25) of the lavas analysed preserve 210Pb deficits with 17 having (210Pb /226Ra) < 0.9 and 7 (210Pb /226Ra) < 0.8 whilst 5 are below (210Pb /226Ra) = 0.6. Of the 14 lavas that have 210Pb excess, 6 have (210Pb /226Ra) > 1.2. Whereas 210Pb deficits are found across the compositional spectrum of lavas analysed (silica = 47-65 percent), (210Pb /226Ra) appears to increase with increasing silica in those lavas that have 210Pb excesses. The 210Pb deficits are most readily interpreted in terms of protracted magma degassing and the numerical model of Gauthier and Condomines 1999 (EPSL 172: 111-126) suggests that the typical duration of degassing is on the order of 10's of years but may reach 45 years in the case of the largest 210Pb deficits at Yasur in Vanuatu, Mt Mayon in the Philippines, Avachinsky in Kamchatka and Spurr, Redoubt and Shishaldin in the Aleutians. These estimates for the duration of degassing represent minimum time scales since they assume 100 percent efficient degassing of 222Rn and no magma replenishment during that period. Therefore, it appears that the majority of arc magmas undergo efficient and protracted degassing for decades prior to eruption. By contrast, there is no simple model for explaining the 210Pb excesses. Mass balance calculations indicate that plagioclase accumulation cannot account for the observed excesses. Instead, we suggest that inefficient gas release and/or sublimation of 210Pb produced by decay from 222Rn during gaseous transport through the magma may be responsible for the

  19. Ecological half-life of 137Cs in fish from a stream contaminated by nuclear reactor effluents.

    PubMed

    Peles, J D; Bryan, A L; Garten, C T; Ribble, D O; Smith, M H

    2000-12-18

    Radiocesium (137Cs) concentrations were determined during 1974, 1981 and 1998 for seven species of fish inhabiting a stream (Steel Creek) contaminated by effluents from a nuclear reactor to examine the decline of this radionuclide in a natural ecosystem. Median 137Cs concentrations were highest in Micropterus salmoides (largemouth bass) during each year of the investigation (1974 = 6.67 Bq g(-1) dry wt. of whole body; 1981 = 3.72 Bq g(-1); 1998 = 0.35 Bq g(-1)), but no patterns of differences were observed among Aphredoderus sayanus (pirate perch), Esox americanus (redfin pickerel), Lepomis auritus (redbreast sunfish), L. gulosus (warmouth), L. punctatus (spotted sunfish), and Notropis cummingsae (dusky shiner). Results demonstrated a rapid decline in 137Cs within fish from Steel Creek during the 24-year period. For example, 137Cs concentrations in all fish species declined significantly among years, even after accounting for radioactive decay. The observed percent declines in 137Cs concentrations of individual species were 3-4 times greater between 1974 and 1981 compared to that expected by physical decay alone, and 2-3 times greater during 1981-1998. Ecological half-lives (EHLs) of 137Cs in fish ranged from 4.43 years in A. sayanus to 6.53 years in L. gulosus. The EHL for 137Cs in all fish species combined was 5.54 years. Current levels of 137Cs in fish from Steel Creek (1.16 Bq g(-1) dry wt. of whole body to below detection limits) indicate that the consumption of fish from this ecosystem poses little risk to humans and sensitive wildlife species. These results demonstrate the importance of incorporating the concept of ecological half-life into determinations concerning the length and severity of potential risks associated with radiocontaminants.

  20. Long-term reduction in (137)Cs concentration in food crops on coral atolls resulting from potassium treatment.

    PubMed

    Robison, William L; Stone, E L; Hamilton, T F; Conrado, C L

    2006-01-01

    Bikini Island was contaminated on March 1, 1954 by the Bravo detonation (U.S. nuclear test series, Castle) at Bikini Atoll. About 90% of the estimated dose from nuclear fallout to potential island residents is from cesium-137 ((137)Cs) transferred from soil to plants that are consumed by residents. Thus, radioecology research efforts have been focused on removing (137)Cs from soil and/or reducing its uptake into vegetation. Most effective was addition of potassium (K) to soil that reduces (137)Cs concentration in fruits to 3-5% of pretreatment concentrations. Initial observations indicated this low concentration continued for some time after K was last applied. Long-term studies were designed to evaluate this persistence in more detail because it is very important to provide assurance to returning populations that (137)Cs concentrations in food (and, therefore, radiation dose) will remain low for extended periods, even if K is not applied annually or biennially. Potassium applied at 300, 660, 1260, and 2070 kg ha(-1) lead to a (137)Cs concentration in drinking-coconut meat that is 34, 22, 10, and about 4% of original concentration, respectively. Concentration of (137)Cs remains low 8-10 y after K is last applied. An explanation for this unexpected result is discussed. PMID:16650918

  1. Long-Term Reduction in 137Cs Concentration in Food Crops on Coral Atolls Resulting from Potassium Treatment

    SciTech Connect

    Robison, W; Stone, E; Hamilton, T; Conrado, C

    2005-04-08

    Bikini Island was contaminated March 1, 1954 by the Bravo detonation (U.S nuclear test series, Castle) at Bikini Atoll. About 90% of the estimated dose from nuclear fallout to potential island residents is from cesium-137 ({sup 137}Cs) transferred from soil to plants that are consumed by residents. Thus, radioecology research efforts have been focused on removing {sup 137}Cs from soil and/or reducing its uptake into vegetation. Most effective was addition of potassium (K) to soil that reduces {sup 137}Cs concentration in fruits to 3-5% of pretreatment concentrations. Initial observations indicated this low concentration continued for some time after K was last applied. Long-term studies were designed to evaluate this persistence in more detail because it is very important to provide assurance to returning populations that {sup 137}Cs concentrations in food (and, therefore, radiation dose) will remain low for extended periods, even if K is not applied annually or biennially. Potassium applied at 300, 660, 1260, and 1970 kg ha{sup -1} lead to a {sup 137}Cs concentration in drinking coconut meat that is 34, 22, 10, and about 4 % of original concentration, respectively. Concentration of {sup 137}Cs remains low 8 to 10 y after K is last applied. An explanation for this unexpected result is discussed.

  2. Long-Term Reduction in 137Cs Concentration in Food Crops on Coral Atolls Resulting from Potassium Treatment

    SciTech Connect

    Robison, W L; Stone, E L; Hamilton, T F; Conrado, C L

    2004-04-14

    Bikini Island was contaminated March 1, 1954 by the Bravo detonation (U.S nuclear test series, Castle) at Bikini Atoll. About 90% of the estimated dose from nuclear fallout to potential island residents is from cesium-137 ({sup 137}Cs) transferred from soil to plants that are consumed by residents. Thus, radioecology research efforts have been focused on removing {sup 137}Cs from soil and/or reducing its uptake into vegetation. Most effective was addition of potassium (K) to soil that reduces {sup 137}Cs concentration in fruits to 3-5% of pretreatment concentrations. Initial observations indicated this low concentration continued for some time after K was last applied. Long-term studies were designed to evaluate this persistence in more detail because it is very important to provide assurance to returning populations that {sup 137}Cs concentrations in food (and, therefore, radiation dose) will remain low for extended periods, even if K is not applied annually or biennially. Potassium applied at 300, 660, 1260, and 2070 kg ha{sup -1} lead to a {sup 137}Cs concentration in drinking coconut meat that is 34, 22, 10, and about 4% of original concentration, respectively. Concentration of {sup 137}Cs remains low 8 to 10 y after K is last applied. An explanation for this unexpected result is discussed.

  3. Long-term reduction in (137)Cs concentration in food crops on coral atolls resulting from potassium treatment.

    PubMed

    Robison, William L; Stone, E L; Hamilton, T F; Conrado, C L

    2006-01-01

    Bikini Island was contaminated on March 1, 1954 by the Bravo detonation (U.S. nuclear test series, Castle) at Bikini Atoll. About 90% of the estimated dose from nuclear fallout to potential island residents is from cesium-137 ((137)Cs) transferred from soil to plants that are consumed by residents. Thus, radioecology research efforts have been focused on removing (137)Cs from soil and/or reducing its uptake into vegetation. Most effective was addition of potassium (K) to soil that reduces (137)Cs concentration in fruits to 3-5% of pretreatment concentrations. Initial observations indicated this low concentration continued for some time after K was last applied. Long-term studies were designed to evaluate this persistence in more detail because it is very important to provide assurance to returning populations that (137)Cs concentrations in food (and, therefore, radiation dose) will remain low for extended periods, even if K is not applied annually or biennially. Potassium applied at 300, 660, 1260, and 2070 kg ha(-1) lead to a (137)Cs concentration in drinking-coconut meat that is 34, 22, 10, and about 4% of original concentration, respectively. Concentration of (137)Cs remains low 8-10 y after K is last applied. An explanation for this unexpected result is discussed.

  4. Long-term simulations of the 137Cs dispersion from the Fukushima accident in the world ocean.

    PubMed

    Nakano, Masanao; Povinec, Pavel P

    2012-09-01

    The LAMER calculation code was used for simulation of the distribution of (137)Cs released after the Fukushima accident into the Pacific and Indian Oceans. The maximum (137)Cs concentration predicted for surface waters of the open NW Pacific Ocean in 2012 (21 Bq/m(3) at 38 °N, 164 °E) will be comparable to that observed during the early 1960s after atmospheric nuclear weapons tests. The (137)Cs in surface waters of the Pacific Ocean will reach the US coast 4-5 y after the accident, however, the levels will be low (<3 Bq/m(3)). All the North Pacific Ocean will be labeled with Fukushima (137)Cs 10 y after the accident with concentrations below 1 Bq/m(3). Thirty years after the accident the (137)Cs levels in the Pacific and Indian Oceans will be below 0.1 Bq/m(3), i.e. undetectable on the present global fallout background. The effective dose commitment with ingestion of marine biota found in 2012 in the open NW Pacific Ocean was estimated to be 1.7 μSv/y, mostly delivered by (134,137)Cs. The estimated dose is by about a factor of 500 lower than the present dose limit for the public. PMID:22244453

  5. Phytoremediation of radiostrontium ((90)Sr) and radiocesium ((137)Cs) using giant milky weed (Calotropis gigantea R.Br.) plants.

    PubMed

    Eapen, Susan; Singh, Shraddha; Thorat, Vidya; Kaushik, C P; Raj, Kanwar; D'Souza, S F

    2006-12-01

    Potential of plants to remove radionuclides/toxic elements from soils and solutions can be successfully applied for removal of important radionuclides such as strontium-90 ((90)Sr) and cesium-137 ((137)Cs). When uptake of (137)Cs and (90)Sr by Calotropis gigantea plants incubated in distilled water spiked with the radionuclides either alone or in combination was studied, it was found to have a high efficiency for the removal of (90)Sr, with 90% being removed from solutions (5 x 10(3)kBql(-1)) within 24h of incubation. However, in case of (137)Cs, about 44% could be removed from solutions (5 x 10(3)kBql(-1)) at the end of 168h of incubation. Accumulation of (90)Sr and (137)Cs was higher in roots compared to shoots. The plants could remediate both (90)Sr and (137)Cs when they were added together to the solution. When two months old plants were incubated in low level nuclear waste, 99% of activity disappeared at the end of 15 days. The present study suggests that C. gigantea could be used as a potential candidate plant for phytoremediation of (90)Sr and (137)Cs.

  6. Aggregated Transfer Factors For Small Mammals Collected From the Exposed Sediments Of A 137 Cs Contaminated Reservoir

    SciTech Connect

    Paller, Michael H.; Jannika, G. Timothy; Wike, Lynn D

    2005-10-04

    {sup 137}Cs transfer factors were computed for small mammals collected from the dried sediment areas of a partially drained, contaminated reservoir. Soil {sup 137}Cs concentrations were heterogeneous on small and large spatial scales, with a geometric mean of 253.1 Bq/kg dry weight. About 50% of the variance in cotton rat Sigmodon hispidus tissue {sup 137}Cs levels was explained by variation in soil {sup 137}Cs levels. Soil to animal transfer factors (whole body dry weight) averaged 6.0 for cotton rats and 1.2 for cotton mice Peromyscus gossypinus. These values are similar to {sup 137}Cs transfer factors for herbivorous, homeothermic animals from other contaminated ecosystems. Site-specific transfer factors can significantly affect the estimation of dose. In the RESRAD-BIOTA dose model, the default transfer factor for {sup 137}Cs in terrestrial animals is 110 resulting in an estimate of radiation dose to terrestrial biota that is 16 times more than the dose calculated with the actual measured transfer factor.

  7. Relationship between the {sup 137}Cs whole-body counting results and soil and food contamination in farms near Chernobyl

    SciTech Connect

    Takatsuji, Toshihiro; Sato, Hitoshi; Takada, Jun

    2000-01-01

    The authors measured the radioactivity in the soil and child food samples from farms near Mogilev (56--270 GBq km{sup {minus}2} {sup 137}Cs), Gomel (36--810 GBq km{sup {minus}2} {sup 137}Cs), and Klincy (59--270 GBq km{sup {minus}2} {sup 137}Cs), who had whole-body {sup 137}Cs counting results measured as part of a health examination in the Chernobyl Sasakawa Health and Medical Cooperation Project. Soil contamination on the family farm seems to be the main source of human contamination because most of the people in the area live on small farms and they and their domestic animals eat crops from the farms. A clear correlation was found between the children's whole-body {sup 137}Cs counting results and the radioactivity in their food (correlation coefficient: 0.76; confidence level of correlation: 3.2 x 10{sup {minus}9}). There were also significant correlations between the whole-body {sup 137}Cs counting results and both the radioactivity of the soil samples (correlation coefficient: 0.22; confidence level of correlation: 0.0107) and the average contamination level of their current residence (correlation coefficient: 0.20; confidence level of correlation: 0.0174).

  8. Inoculation with arbuscular mycorrhizae does not improve 137Cs uptake in crops grown in the Chernobyl region.

    PubMed

    Vinichuk, M; Mårtensson, A; Rosén, K

    2013-12-01

    Methods for cleaning up radioactive contaminated soils are urgently needed. In this study we investigated whether the use of arbuscular mycorrhizal (AM) fungi can improve (137)Cs uptake by crops. Barley, cucumber, perennial ryegrass, and sunflower were inoculated with AM fungi and grown in low-level radionuclide contaminated soils in a field experiment 70 km southwest of Chernobyl, Ukraine, during two successive years (2009-2010). Roots of barley, cucumber and sunflower plants were slightly or moderately infected with AM fungus and root infection frequency was negatively or non-correlated with (137)Cs uptake by plants. Roots of ryegrass were moderately infected with AM fungus and infection frequency was moderately correlated with (137)Cs uptake by ryegrass. The application of AM fungi to soil in situ did not enhance radionuclide plant uptake or biomass. The responsiveness of host plants and AM fungus combination to (137)Cs uptake varied depending on the soil, although mycorrhization of soil in the field was conditional and did not facilitate the uptake of radiocesium. The total amount of (137)Cs uptake by plants growing on inoculated soil was equal to amounts in plant cultivated on non-inoculated soil. Thus, the use of AM fungi in situ for bioremediation of soil contaminated with a low concentration of (137)Cs could not be recommended. PMID:23933082

  9. Long-term simulations of the 137Cs dispersion from the Fukushima accident in the world ocean.

    PubMed

    Nakano, Masanao; Povinec, Pavel P

    2012-09-01

    The LAMER calculation code was used for simulation of the distribution of (137)Cs released after the Fukushima accident into the Pacific and Indian Oceans. The maximum (137)Cs concentration predicted for surface waters of the open NW Pacific Ocean in 2012 (21 Bq/m(3) at 38 °N, 164 °E) will be comparable to that observed during the early 1960s after atmospheric nuclear weapons tests. The (137)Cs in surface waters of the Pacific Ocean will reach the US coast 4-5 y after the accident, however, the levels will be low (<3 Bq/m(3)). All the North Pacific Ocean will be labeled with Fukushima (137)Cs 10 y after the accident with concentrations below 1 Bq/m(3). Thirty years after the accident the (137)Cs levels in the Pacific and Indian Oceans will be below 0.1 Bq/m(3), i.e. undetectable on the present global fallout background. The effective dose commitment with ingestion of marine biota found in 2012 in the open NW Pacific Ocean was estimated to be 1.7 μSv/y, mostly delivered by (134,137)Cs. The estimated dose is by about a factor of 500 lower than the present dose limit for the public.

  10. Long-term decline of 137Cs concentration in honey in the second decade after the Chernobyl accident.

    PubMed

    Panatto, Donatella; Gasparini, Roberto; Lai, Piero; Rovatti, Paola; Gallelli, Giovanni

    2007-08-15

    In the years 2001-2004 the (137)Cs activity was investigated in a total of 336 samples of different varieties of honey harvested in the Liguria Region of Northern Italy. Our purpose was to define (a) residual radioactive contamination following the Chernobyl accident and (137)Cs long-term decline, (b) correlation between (137)Cs activity and different honey varieties, and (c) correlation between (137)Cs activity and the prevailing geomorphological configuration in the collection areas. The mean (137)Cs specific activity was 4.33+/-5.04 S.D. Bq/kg. Chestnut honey showed higher levels of radioactive contamination, which were ascribed to the extensive, superficial and deep, root apparatus of the tree. Honey samples from acidic argillite soils, which withhold radionuclides after deposition and slowly release them to plants, also showed higher (137)Cs activity. Long-term decline was calculated at 456 days, a value lower than those published from different food sources in the years following the accident. The rate of long-term decline decreases with time.

  11. Biomonitoring fallout 137Cs in resident and migratory fishes collected along the southern coast of India and assessment of dose.

    PubMed

    Khan, Mohan Feroz; Wesley, Samuel Godwin

    2012-05-01

    The globally distributed fallout radionuclide (137)Cs was monitored in 25 resident and 22 migratory fish species collected from some regions of west and east coast of southern India to establish a baseline data. The samples were collected during June 2008 to June 2009. Higher level of (137)Cs was noted in planktivorous fishes and lower level in herbivores. A significant variation in (137)Cs was observed between fishes with different feeding habits and different migratory pattern. Oceanodromic migratory fishes displayed higher cesium levels than other migratory types. Similarly, migratory fishes displayed higher (137)Cs concentration compared to resident fishes. The overall range of (137)Cs varied from 0.06 to 0.3 Bq/kg in fishes. The biological concentration varied from 55 to 250. The average external dose rate to fishes was calculated to be 2.7 × 10(-7) μGy/h, while the internal dose rate varied from 8.50 × 10(-6) to 5.27 × 10(-5) μGy/h. The hazard quotient for fishes was found to be less than 1. The average intake of (137)Cs via fishes to the public was calculated to be 3.5 Bq/year and subsequently the committed effective dose was 0.05 μSv/year. The data obtained were less than global average and comparable to those of many regions.

  12. The usefulness of 137Cs as a tracer for soil erosion assessment: A critical reply to Parsons and Foster (2011)

    NASA Astrophysics Data System (ADS)

    Mabit, L.; Meusburger, K.; Fulajtar, E.; Alewell, C.

    2013-12-01

    A large number of geoscientists worldwide from different disciplines have recognized and have adopted the 137Cs method as an effective tracer to assess soil erosion rates during the last decades. The recent review of Parsons and Foster (2011) challenged the usefulness of this radioisotopic method primarily by questioning the assumption of the representativeness of the reference inventory and its conservative behavior and the 137Cs data conversion into soil erosion rates. While there are many studies published on 137Cs method, Parsons and Foster (2011) have not evaluated the full range of the existing literature. We present additional highly relevant studies, assessing and applying the 137Cs method successfully. While we agree that the applicability of the 137Cs method to assess soil erosion magnitude needs careful planning as well as expert knowledge, we highlight in our reply that if the method is based on suitable and statistically sound sampling, 137Cs is a very effective soil tracer to assess soil erosion magnitude.

  13. Influence of submarine groundwater discharge on (210)Po and (210)Pb bioaccumulation in fish tissues.

    PubMed

    Garcia-Orellana, J; López-Castillo, E; Casacuberta, N; Rodellas, V; Masqué, P; Carmona-Catot, G; Vilarrasa, M; García-Berthou, E

    2016-05-01

    This study presents the results of the accumulation of (210)Po and (210)Pb in fish tissues and organs in a brackish-water marshland that is characterized by high concentrations of (222)Rn and (226)Ra supplied by submarine groundwater discharge (SGD). Tissues and organs from Cyprinus carpio, Chelon labrosus and Carassius auratus in the wetland were significantly enriched by both (210)Pb and (210)Po (up to 55 and 66 times, respectively) compared to blanks. The major input route of (210)Pb and (210)Po into the fish body seems to be through ingestion, due to the high levels of (210)Pb and (210)Po found in the gut content as well as in organs involved in digestion and metabolism (i.e. gut, kidney and hepatopancreas). Results showed that (210)Po was more accumulated in all fish tissues and organs except for the spine, which showed a higher affinity for (210)Pb, due to its capacity to replace Ca from apatite in bones. Over all the variables analyzed, fish tissues/organs and, secondarily, fish species were the most important factors explaining the concentration of radionuclides, whereas fish length and the sampling location played a minor role. The relationship of the two radionuclides varied markedly among tissues and their concentration levels were only correlated in gills, gut and, marginally, in spines. In general, the highest values of (210)Pb and (210)Po concentrations in tissues were found on C. labrosus tissues rather C. auratus and C. carpio. This study demonstrates that inputs of natural radionuclides supplied by SGD to coastal semi-enclosed areas (such as marshlands, lagoons or ponds) may significantly increase the contents of (210)Pb and (210)Po in fish tissues/organs. Thus, this study represents one of the first evidences of direct ecological effects derived from SGD. PMID:26913976

  14. Decay/ingrowth uncertainty correction of (210)Po/(210)Pb in seawater.

    PubMed

    Lin, Wuhui; Ma, Hao; Chen, Liqi; Zeng, Zhi; He, Jianhua; Zeng, Shi

    2014-11-01

    Due to increasing application of (210)Po/(210)Pb in studying particle dynamics, a consistent procedure and calculation to derive accurate and precise result of (210)Po and (210)Pb in seawater should be proposed in the framework of intercalibration by GEOTRACES. The associated uncertainty of radioactivity, which is a significant component of data report, plays a vital role in intercomparison and should be well evaluated. Although measurement uncertainty of laboratory result was well defined in ISO standards and IAEA technical documents, the decay/ingrowth uncertainty correction from laboratory result to in-situ result was less studied. It was demonstrated that the relative uncertainty of in-situ (210)Pb activity was independent of elapsed time and equal to relative uncertainty of laboratory measuring (210)Po activity at second spontaneous deposition date. The relative uncertainty of in-situ (210)Po activity decreases with in-situ activity ratio of (210)Po to (210)Pb and increases with elapsed time between sampling date and separation date, relative uncertainty of laboratory measuring (210)Po activity at first spontaneous deposition date and relative uncertainty of in-situ (210)Pb activity. It was more important to improve precision of (210)Po at first spontaneous deposition date than that of (210)Po at second spontaneous deposition date. To obtain a desirable relative uncertainty of in-situ (210)Po activity, the maximum allowing elapsed time for (210)Po, which was important for sampling strategy making and quality assurance, was calculated by in-situ activity ratio of (210)Po to (210)Pb and precision of analytical method for (210)Po. The methodology of decay/ingrowth uncertainty correction could also be applied for other radionuclide pairs ((234)Th/(238)U, (90)Y/(90)Sr, (210)Bi/(210)Pb), sample matrixes (aerosols), and disciplines. PMID:24992240

  15. Decay/ingrowth uncertainty correction of (210)Po/(210)Pb in seawater.

    PubMed

    Lin, Wuhui; Ma, Hao; Chen, Liqi; Zeng, Zhi; He, Jianhua; Zeng, Shi

    2014-11-01

    Due to increasing application of (210)Po/(210)Pb in studying particle dynamics, a consistent procedure and calculation to derive accurate and precise result of (210)Po and (210)Pb in seawater should be proposed in the framework of intercalibration by GEOTRACES. The associated uncertainty of radioactivity, which is a significant component of data report, plays a vital role in intercomparison and should be well evaluated. Although measurement uncertainty of laboratory result was well defined in ISO standards and IAEA technical documents, the decay/ingrowth uncertainty correction from laboratory result to in-situ result was less studied. It was demonstrated that the relative uncertainty of in-situ (210)Pb activity was independent of elapsed time and equal to relative uncertainty of laboratory measuring (210)Po activity at second spontaneous deposition date. The relative uncertainty of in-situ (210)Po activity decreases with in-situ activity ratio of (210)Po to (210)Pb and increases with elapsed time between sampling date and separation date, relative uncertainty of laboratory measuring (210)Po activity at first spontaneous deposition date and relative uncertainty of in-situ (210)Pb activity. It was more important to improve precision of (210)Po at first spontaneous deposition date than that of (210)Po at second spontaneous deposition date. To obtain a desirable relative uncertainty of in-situ (210)Po activity, the maximum allowing elapsed time for (210)Po, which was important for sampling strategy making and quality assurance, was calculated by in-situ activity ratio of (210)Po to (210)Pb and precision of analytical method for (210)Po. The methodology of decay/ingrowth uncertainty correction could also be applied for other radionuclide pairs ((234)Th/(238)U, (90)Y/(90)Sr, (210)Bi/(210)Pb), sample matrixes (aerosols), and disciplines.

  16. Fractionation of 210Po and 210Pb in coastal waters of the NW Mediterranean continental margin

    NASA Astrophysics Data System (ADS)

    Tateda, Yutaka; Carvalho, Fernando P.; Fowler, Scott W.; Miquel, Juan-Carlos

    2003-03-01

    The natural radionuclides 210Po and 210Pb were analyzed in samples of surface sea water, rain and dry fallout, and river water collected along the NW Mediterranean coast as well as from a sediment trap moored 3 km south of Monaco. Using a box model calculation, the balances and fluxes of 210Po and 210Pb in the coastal waters of the NW Mediterranean were estimated. Atmospheric inputs of 210Po and 210Pb to Monaco coastal waters varied seasonally and were maximal in winter when storms and strong winds transfered continental 222Rn-rich air and aerosols of top soil particles to coastal surface waters, which in turn enhanced the 210Po and 210Pb input to these waters. The balance estimation using all fluxes in surface waters indicated that 210Pb was removed from surface water with residence times of 2.1, 0.40, and 2.7 years for dissolved, particulate, and total 210Pb, respectively. In the bottom water and surface sediments, additional excess 210Pb sinking and sedimentation fluxes were observed, suggesting a substantial down slope transport of sediment particles. Similarly, the residence times of 210Po in surface water were 1.2, 0.38, and 0.77 years for dissolved, particulate, and total 210Po, respectively; however, a deficit in the 210Po sinking flux in the bottom layer, compared to removal flux from the surface waters, suggested rapid degradation of 210Po-bearing biogenic particles during sinking following periods of low biological productivity.

  17. Influence of submarine groundwater discharge on (210)Po and (210)Pb bioaccumulation in fish tissues.

    PubMed

    Garcia-Orellana, J; López-Castillo, E; Casacuberta, N; Rodellas, V; Masqué, P; Carmona-Catot, G; Vilarrasa, M; García-Berthou, E

    2016-05-01

    This study presents the results of the accumulation of (210)Po and (210)Pb in fish tissues and organs in a brackish-water marshland that is characterized by high concentrations of (222)Rn and (226)Ra supplied by submarine groundwater discharge (SGD). Tissues and organs from Cyprinus carpio, Chelon labrosus and Carassius auratus in the wetland were significantly enriched by both (210)Pb and (210)Po (up to 55 and 66 times, respectively) compared to blanks. The major input route of (210)Pb and (210)Po into the fish body seems to be through ingestion, due to the high levels of (210)Pb and (210)Po found in the gut content as well as in organs involved in digestion and metabolism (i.e. gut, kidney and hepatopancreas). Results showed that (210)Po was more accumulated in all fish tissues and organs except for the spine, which showed a higher affinity for (210)Pb, due to its capacity to replace Ca from apatite in bones. Over all the variables analyzed, fish tissues/organs and, secondarily, fish species were the most important factors explaining the concentration of radionuclides, whereas fish length and the sampling location played a minor role. The relationship of the two radionuclides varied markedly among tissues and their concentration levels were only correlated in gills, gut and, marginally, in spines. In general, the highest values of (210)Pb and (210)Po concentrations in tissues were found on C. labrosus tissues rather C. auratus and C. carpio. This study demonstrates that inputs of natural radionuclides supplied by SGD to coastal semi-enclosed areas (such as marshlands, lagoons or ponds) may significantly increase the contents of (210)Pb and (210)Po in fish tissues/organs. Thus, this study represents one of the first evidences of direct ecological effects derived from SGD.

  18. A first attempt to derive soil erosion rates from 137Cs airborne gamma measurements in two Alpine valleys

    NASA Astrophysics Data System (ADS)

    Arata, Laura; Meusburger, Katrin; Bucher, Benno; Mabit, Lionel; Alewell, Christine

    2016-04-01

    The application of fallout radionuclides (FRNs) as soil tracers is currently one of the most promising and effective approach for evaluating soil erosion magnitudes in mountainous grasslands. Conventional assessment or measurement methods are laborious and constrained by the topographic and climatic conditions of the Alps. The 137Cs (half-life = 30.2 years) is the most frequently used FRN to study soil redistribution. However the application of 137Cs in alpine grasslands is compromised by the high heterogeneity of the fallout due to the origin of 137Cs fallout in the Alps, which is linked to single rain events occurring just after the Chernobyl accident when most of the Alpine soils were still covered by snow. The aim of this study was to improve our understanding of the 137Cs distribution in two study areas in the Central Swiss Alps: the Ursern valley (Canton Uri), and the Piora valley (Canton Ticino). In June 2015, a helicopter equipped with a NaI gamma detector flew over the two study sites and screened the 137Cs activity of the top soil. The use of airborne gamma measurements is particularly efficient in case of higher 137Cs concentration in the soil. Due to their high altitude and high precipitation rates, the Swiss Alps are expected to be more contaminated by 137Cs fallout than other parts of Switzerland. The airborne gamma measurements have been related to several key parameters which characterize the areas, such as soil properties, slopes, expositions and land uses. The ground truthing of the airborne measurements (i.e. the 137Cs laboratory measurements of the soil samples collected at the same points) returned a good fit. The obtained results offer an overview of the 137Cs concentration in the study areas, which allowed us to identify suitable reference sites, and to analyse the relationship between the 137Cs distribution and the above cited parameters. The authors also derived a preliminary qualitative and a quantitative assessment of soil redistribution

  19. Detection of /sup 210/Pb in the lungs of smokers by in-vivo gamma spectrometry

    SciTech Connect

    Berger, C.D.; Lane, B.H.

    1982-09-01

    Since mainstream smoke is highly enriched in /sup 210/Pb, alpha radiation from inhaled cigarette smoke particles has been proposed as a cancer-producing agent in cigarette smokers. /sup 210/Po and /sup 210/Pb have been observed in tobacco, cigarette smoke and in the lungs of smokers. Since /sup 210/Pb is highly enriched in mainstream smoke, there have been estimates of yearly excesses of /sup 210/Pb in the lungs of one-pack-a-day smokers of 3 to 10 pCi (0.11 to 0.37 Bq). The ORNL Whole Body Counter was used to verify this estimate by the methodology of high-resolution, in vivo gamma spectrometry. Measurements were made on 113 adult male non-radiation workers who have either smoked at least one pack of cigarettes per day for at least five years, or have never smoked cigarettes. An analysis-of-variance table was generated based on the Pb-ratio for each individual which revealed that there was no statistically significant increase in the amount of /sup 210/Pb in the lungs of smokers over those of non-smokers. Sources of error are also discussed.

  20. Apportioning global and non-global components of mercury deposition through (210)Pb indexing.

    PubMed

    Lamborg, Carl H; Engstrom, Daniel R; Fitzgerald, William F; Balcom, Prentiss H

    2013-03-15

    Our previous work has documented a correlation between Hg concentrations and (210)Pb activity measured in wet deposition that might be used to help apportion sources of Hg in precipitation. Here we present the results of a 27-month precipitation collection effort using co-located samplers for Hg and (210)Pb designed to assess this hypothesis. Study sites were located on the east and west coasts of North America, in the continental interior, and on the Florida Peninsula. Relatively high variability in Hg/(210)Pb ratios was found at all sites regionally and seasonally (e.g., overall: 0.99-9.13ngdpm(-1)). The ratio of average volume-weighted Hg concentrations and (210)Pb activities showed consistent trends (higher in impacted area), with Glacier Bay in southeast Alaska, exhibiting the lowest value. Assuming that Glacier Bay represents a benchmark for a site with no regional contribution, we estimate less than 50% of the Hg input was "global" at the Seattle and Florida sites. Differences in Hg/(210)Pb in wet deposition could be due to either a regional/local source contribution of Hg, or a regional/local enhancement in the removal of Hg from the atmosphere (i.e., oxidants), however, this approach is not capable of discerning between these two possibilities. Thus, this method of source apportionment represents an estimate of the maximal amount of Hg contributed by regional sources and may be limited in regions of deep convective mixing.

  1. Analysis of (210)Pb in water samples with plastic scintillation resins.

    PubMed

    Lluch, E; Barrera, J; Tarancón, A; Bagán, H; García, J F

    2016-10-12

    (210)Pb is a radioactive lead isotope present in the environment as member of the (238)U decay chain. Since it is a relatively long-lived radionuclide (T1/2 = 22.2 years), its analysis is of interest in radiation protection and the geochronology of sediments and artwork. Here, we present a method for analysing (210)Pb using plastic scintillation resins (PSresins) packaged in solid-phase extraction columns (SPE cartridge). The advantages of this method are its selectivity, the low limit of detection, as well as reductions in the amount of time and reagents required for analysis and the quantity of waste generated. The PSresins used in this study were composed of a selective extractant (4',4″(5″)-Di-tert-butyldicyclohexano-18-crown-6 in 1-octanol) covering the surface of plastic scintillation microspheres. Once the amount of extractant (1:1/4) and medium of separation (2 M HNO3) were optimised, PSresins in SPE cartridges were calibrated with a standard solution of (210)Pb. (210)Pb could be fully separated from its daughters, (210)Bi and (210)Po, with a recovery value of 91(3)% and detection efficiency of 44(3)%. Three spiked water samples (one underground and two river water samples) were analysed in triplicates with deviations lower than 10%, demonstrating the validity of the PS resin method for (210)Pb analysis. PMID:27662757

  2. Analysis of (210)Pb in water samples with plastic scintillation resins.

    PubMed

    Lluch, E; Barrera, J; Tarancón, A; Bagán, H; García, J F

    2016-10-12

    (210)Pb is a radioactive lead isotope present in the environment as member of the (238)U decay chain. Since it is a relatively long-lived radionuclide (T1/2 = 22.2 years), its analysis is of interest in radiation protection and the geochronology of sediments and artwork. Here, we present a method for analysing (210)Pb using plastic scintillation resins (PSresins) packaged in solid-phase extraction columns (SPE cartridge). The advantages of this method are its selectivity, the low limit of detection, as well as reductions in the amount of time and reagents required for analysis and the quantity of waste generated. The PSresins used in this study were composed of a selective extractant (4',4″(5″)-Di-tert-butyldicyclohexano-18-crown-6 in 1-octanol) covering the surface of plastic scintillation microspheres. Once the amount of extractant (1:1/4) and medium of separation (2 M HNO3) were optimised, PSresins in SPE cartridges were calibrated with a standard solution of (210)Pb. (210)Pb could be fully separated from its daughters, (210)Bi and (210)Po, with a recovery value of 91(3)% and detection efficiency of 44(3)%. Three spiked water samples (one underground and two river water samples) were analysed in triplicates with deviations lower than 10%, demonstrating the validity of the PS resin method for (210)Pb analysis.

  3. Atmospheric deposition patterns of (210)Pb and (7)Be in Cienfuegos, Cuba.

    PubMed

    Alonso-Hernández, Carlos M; Morera-Gómez, Yasser; Cartas-Águila, Héctor; Guillén-Arruebarrena, Aniel

    2014-12-01

    The radiometric composition of bulk deposition samples, collected monthly for one year, February 2010 until January 2011, at a site located in Cienfuegos (22° 03' N, 80° 29' W) (Cuba), are analysed in this paper. Measurement of (7)Be and (210)Pb activity concentrations were carried out in 12 bulk deposition samples. The atmospheric deposition fluxes of (7)Be and (210)Pb are in the range of 13.2-132 and 1.24-8.29 Bq m(-2), and their mean values are: 56.6 and 3.97 Bq m(-2), respectively. The time variations of the different radionuclide have been discussed in relation with meteorological factors and the mean values have been compared to those published in recent literature from other sites located at different latitudes. The annual average flux of (210)Pb and (7)Be were 47 and 700 Bq m(-2) y(-1), respectively. Observed seasonal variations of deposition data are explained in terms of different environmental features. The atmospheric deposition fluxes of (7)Be and (210)Pb were moderately well correlated with precipitation and well correlated with one another. The (210)Pb/(7)Be ratios in the monthly depositions samples varied in the range of 0.05-0.10 and showed a strong correlation with the number of rainy days.

  4. Modelling the 137Cs ingestion dose from consumption of marine fish in Hong Kong.

    PubMed

    Poon, C B; Au, S M

    2002-01-01

    This paper presents a compartmental model for estimating the ingestion dose, due to 137Cs, arising from the consumption of marine fish in Hong Kong. 137Cs is one of the more important radionuclides released in routine liquid effluents discharged from the Guangdong Nuclear Power Station at Daya Bay, which began commercial operation in 1994. In the model, three sea/ocean compartments are considered. Assuming the discharge of this radionuclide is maintained at a constant rate, the model shows that the concentration of 137Cs in the water and in the marine fish in the three sea compartments would become steady after 5 years. The predicted annual dose to an average local individual in Hong Kong, for a release rate of 10 GBq.y(-1), is 3.2 x 10(-5) microSv, which is dominated by the contribution from fish cultured in Hong Kong waters. The cumulative collective dose to the local population of 6 million, at 50 years of discharge, amounts to 9.0 x 10(-3) man.Sv. The annual dose to members of the critical group of local fish farmers does not exceed 3.0 x 10(-3) microSv. All these doses are small compared to the dose of around 1.2 microSv.y(-1) arising from ingestion of naturally occurring radionuclides found in marine fish. Sensitivity of model parameters and uncertainties of prediction are also studied. Difficulties encountered in model validation are discussed. Despite such difficulties. limited field data that are available show that the predicted results are generally within one order of magnitude with measurements.

  5. Spatial uncertainty of 137Cs-derived net (1950s-1990) soil redistribution for Australia

    NASA Astrophysics Data System (ADS)

    Chappell, Adrian; Viscarra Rossel, Raphael A.; Loughran, Robert

    2011-12-01

    The caesium-137 (137Cs) technique has been used successfully in many parts of the world to estimate net (ca. 30-50 years) soil redistribution by wind and water erosion and tillage activities. The point-based technique has hitherto been confined largely to individual fields and hillslopes, particularly in Australia. Its application here to the Australian continent (≈5 km grid) was achieved using geostatistics and nationally coordinated measurements (early 1990s) from ≈200 locations at the ≈1 km scale. A map of the 137Cs reference inventory for Australia has been previously established. Sequential indicator co-simulation of the 137Cs inventory and the Australian Soil Classification was used to estimate net (between mid-1950s and early 1990s) soil redistribution using the Australian Empirical Model. This geostatistical approach showed that nearly five times more soil was lost from cultivated land (-4.29 to +0.17 t ha-1 yr-1) than from uncultivated (-0.91 to +0.05 t ha-1 yr-1) land in Australia. This information on spatial uncertainty is essential for regional soil management to assess the risk to soil conservation. Soil erosion exceeding a tolerable threshold value (e.g., 0.5 t ha-1 yr-1) occurred over 16% of Australia, mainly in cultivated regions (median = -1.26 t ha-1 yr-1). Soil erosion estimates are neglected in carbon balances for greenhouse gas abatement and carbon accounting models. Reliable quantitative data on the recent extent and rates of soil erosion are needed to underpin the selection of effective soil conservation measures, to inform carbon balances and to understand regional soil function for sustainable agricultural systems.

  6. Freundlich and dual Langmuir isotherm models for predicting 137Cs binding on Savannah River Site soils.

    PubMed

    Goto, Momoko; Rosson, Robert; Wampler, J Marion; Elliott, W Crawford; Serkiz, Steven; Kahn, Bernd

    2008-01-01

    Distribution of 137Cs and stable cesium between aqueous solution and near-surface soil samples from five locations at the Savannah River Site was measured in order to develop a predictive model for 137Cs uptake by the soils. Sorption of 137Cs in these soils appears to be mostly by hydroxy-interlayered vermiculite. Batch sorption studies with 4 d for equilibration were conducted at three cesium concentrations and at two backing electrolyte (NaNO3) concentrations. The soil-solution mixtures were pH-adjusted to evaluate the effects of pH on cesium sorption. Sorbed cesium was related to the equilibrium aqueous cesium concentrations by a Freundlich isotherm model. Model fits on logarithmic scales have a common slope of 0.60 +/- 0.03 for acidic mixtures and 0.69 +/- 0.04 for neutralized mixtures but have unique intercepts that are influenced by backing electrolyte concentration and pH. An ion-exchange model is proposed that pertains to all five soils and relates the Freundlich isotherms to the cation exchange capacity of soil and the aqueous concentrations of cesium, sodium, and a third ionic species that was hydrogen in the acidic mixtures and potassium in the neutralized mixtures. Model fits are consistent with Kd values in the entire range of 5-2,300 L kg(-1) determined for the five soil types. As an alternate model, dual Langmuir isotherms were fitted to the data. The results suggest cesium sorption by (1) relatively few interlayer-wedge sites, highly selective for cesium, and (2) much more abundant but less selective sites on internal and external planar surfaces.

  7. Flow cytometric DNA analysis of ducks accumulating 137Cs on a reactor reservoir.

    PubMed

    George, L S; Dallas, C E; Brisbin, I L; Evans, D L

    1991-06-01

    The objective of this study was to detect red blood cell (rbc) DNA abnormalities in male, game-farm mallard ducks as they ranged freely and accumulated 137Cs (radiocesium) from an abandoned nuclear reactor cooling reservoir. Prior to release, the ducks were tamed to enable recapture at will. Flow cytometric measurements conducted at intervals during the first year of exposure yielded cell cycle percentages of DNA (G0/G1, S, G2 + M phases) of rbc, as well as coefficients of variation (CV) in the G0/G1 phase. DNA histograms of exposed ducks were compared with two sets of controls which were maintained 30 and 150 miles from the study site. 137Cs live wholebody burdens were also measured in these animals in a parallel kinetics study, and an approximate steady-state equilibrium was attained after about 8 months. DNA histograms from 2 of the 14 contaminated ducks revealed DNA aneuploid-like patterns after 9 months exposure. These two ducks were removed from the experiment at this time, and when sampled again 1 month later, one continued to exhibit DNA aneuploidy. None of the control DNA histograms demonstrated DNA aneuploid-like patterns. There were no significant differences in cell cycle percentages at any time point between control and exposed animals. A significant increase in CV was observed at 9 months exposure, but after removal of the two ducks with DNA aneuploidy, no significant difference was detected in the group monitored after 12 months exposure. An increased variation in the DNA and DNA aneuploidy could, therefore, be detected in duck rbc using flow cytometric analysis, with the onset of these effects being related to the attainment of maximal levels of 137Cs body burdens in the exposed animals.

  8. The extraction of {sup 137}Cs and {sup 89}Sr from waste simulants using pillared montmorillonite

    SciTech Connect

    Sylvester, P.; Clearfield, A.

    1998-08-01

    Two samples of a silica-pillared montmorillonite produced using 3-aminopropyltrimethoxy silane and an alumina-pillared montmorillonite were evaluated for the removal of {sup 137}Cs and {sup 89}Sr from a simulated nuclear waste solution and a simulated groundwater, and the results were compared to the parent montmorillonite and two zeolites, AW500 (chabazite) and clinoptilolite. The parent and pillared clays were characterized using x-ray powder diffraction and surface area analysis by nitrogen adsorption/desorption studies. The pillared clays exhibited d-spacings of between 17.43 and 18.32 {angstrom} after calcination, and surface areas ranging from 71.3 to 264.4 m{sup 2}/g. Both of the silica-pillared clays and the alumina-pillared clay exhibited excellent K{sub d}s for {sup 137}Cs from simulated groundwater with values of 23,650, 23,260 and 144,570 mL/g, respectively. These were far better than the K{sub d}s obtained by clinoptilolite and AW500 which had K{sub d}s of only 14,560 and 9,650 mL/g, respectively. None of the pillared clays showed a high selectivity for {sup 89}Sr from groundwater or {sup 137}Cs from simulated alkaline tank waste. They did, however, show a slight selectivity for {sup 89}Sr in the simulated Hanford tank wastes, but this is thought to be due to a precipitation mechanism rather than to ion exchange.

  9. Further studies on the distribution of 137Cs in British coastal waters—I. Irish Sea

    NASA Astrophysics Data System (ADS)

    Jefferies, D. F.; Steele, A. K.; Preston, A.

    1982-06-01

    The concentrations of 137Cs, discharged to the northeast Irish Sea from the British Nuclear Fuels Limited (BNFL) Windscale Works, Cumbria, have been measured in the Irish Sea and its approaches during 1970 to 1978. Seawater labelled by 137Cs has been used to study the variability of local and distant dispersion and to estimate residence times and volume transports. In the immediate vicinity of the outfall a release rate of 1 Ci d -1 produces a mean annual concentration of 4.2 pCi l -1 (2.6 to 6.3 pCi l -1) with an approximate 30-fold reduction to 0.15 pCi l -1 in the northern exit to the Irish Sea and at least a 300-fold reduction at the southern entrance. The release rate ranged from 60 to 400 Ci d -1 (annual average) during the study period. The main flow patterns are deduced and show a substantial change before and after 1976. Using estimated inventories of the radionuclide in various areas, the rate of input into the system, and a simple exponential model, the residence 'half time' of water east of a line south from Scotland through the Isle of Man to Anglesey is estimated to be 200 days. The estimate for the whole northern Irish Sea was 1 year between 1970 and 1976, with a sharp reduction thereafter. The change is confirmed by estimating the volume transport through the North Channel from data from the Stranraer-Larne, Fishguard-Rosslare, and Swansea-Cork ferries. The mean flow through the Irish Sea for the period October 1971 to May 1978 was 5 km 3 d -1 with mean flows of 3.4 km 3 d -1 prior to January 1976 and 7.9 km 3 d -1 thereafter to May 1978. Transit times from the discharge point to the North Channel have also been estimated from the change in concentration of the radionuclides 137Cs( t1/2 = 30.1 y) and 134Cs( t1/2 = 2.1 y) and from serial correlation of rates of discharge and concentrations of 137Cs at distance.

  10. In Situ Remediation of {sup 137}Cs Contaminated Wetlands Using Naturally Occurring Minerals

    SciTech Connect

    Kaplan, D.I.

    1999-08-11

    Cesium-137 has contaminated a large area of the wetlands on the Savannah River Site. Remediation of the contaminated wetlands is problematic because current techniques destroy the sensitive ecosystem and generate a higher dose to workers. To address this problem, we proposed a non-trusive, in situ technology to sequester 137Cs in sediments. One intention of this study was to provide information regarding a go/no go decision for future work. Since the proof-of-concept was successful and several minerals were identified as potential candidates for this technology, a go decision was made.

  11. Simulation and Measurement of Absorbed Dose from 137 Cs Gammas Using a Si Timepix Detector

    NASA Technical Reports Server (NTRS)

    Stoffle, Nicholas; Pinsky, Lawrence; Empl, Anton; Semones, Edward

    2011-01-01

    The TimePix readout chip is a hybrid pixel detector with over 65k independent pixel elements. Each pixel contains its own circuitry for charge collection, counting logic, and readout. When coupled with a Silicon detector layer, the Timepix chip is capable of measuring the charge, and thus energy, deposited in the Silicon. Measurements using a NIST traceable 137Cs gamma source have been made at Johnson Space Center using such a Si Timepix detector, and this data is compared to simulations of energy deposition in the Si layer carried out using FLUKA.

  12. Modeling dynamics of (137)Cs in forest surface environments: Application to a contaminated forest site near Fukushima and assessment of potential impacts of soil organic matter interactions.

    PubMed

    Ota, Masakazu; Nagai, Haruyasu; Koarashi, Jun

    2016-05-01

    A process-based model for (137)Cs transfer in forest surface environments was developed to assess the dynamic behavior of Fukushima-derived (137)Cs in a Japanese forest. The model simulation successfully reproduced the observed data from 3year migration of (137)Cs in the organic and mineral soil layers at a contaminated forest near Fukushima. The migration of (137)Cs from the organic layer to the mineral soil was explained by the direct deposition pattern on the forest floor and the turnover of litter materials in the organic layer under certain ecological conditions. Long-term predictions indicated that more than 90% of the deposited (137)Cs would remain within the top 5cm of the soil for up to 30years after the accident, suggesting that the forest acts as an effective long-term reservoir of (137)Cs with limited transfer via the groundwater pathway. The model was also used to explore the potential impacts of soil organic matter (SOM) interactions on the mobility and bioavailability of (137)Cs in the soil-plant system. The simulation results for hypothetical organic soils with modified parameters of (137)Cs turnover revealed that the SOM-induced reduction of (137)Cs adsorption elevates the fraction of dissolved (137)Cs in the soil solution, thereby increasing the soil-to-plant transfer of (137)Cs without substantially altering the fractional distribution of (137)Cs in the soil. Slower fixation of (137)Cs on the flayed edge site of clay minerals and enhanced mobilization of the clay-fixed (137)Cs in organic-rich soils also appeared to elevate the soil-to-plant transfer of (137)Cs by increasing the fraction of the soil-adsorbed (exchangeable) (137)Cs. A substantial proportion (approximate 30%-60%) of (137)Cs in these organic-rich soils was transferred to layers deeper than 5cm decades later. These results suggested that SOM influences the behavior of (137)Cs in forests over a prolonged period through alterations of adsorption and fixation in the soil.

  13. Modeling dynamics of (137)Cs in forest surface environments: Application to a contaminated forest site near Fukushima and assessment of potential impacts of soil organic matter interactions.

    PubMed

    Ota, Masakazu; Nagai, Haruyasu; Koarashi, Jun

    2016-05-01

    A process-based model for (137)Cs transfer in forest surface environments was developed to assess the dynamic behavior of Fukushima-derived (137)Cs in a Japanese forest. The model simulation successfully reproduced the observed data from 3year migration of (137)Cs in the organic and mineral soil layers at a contaminated forest near Fukushima. The migration of (137)Cs from the organic layer to the mineral soil was explained by the direct deposition pattern on the forest floor and the turnover of litter materials in the organic layer under certain ecological conditions. Long-term predictions indicated that more than 90% of the deposited (137)Cs would remain within the top 5cm of the soil for up to 30years after the accident, suggesting that the forest acts as an effective long-term reservoir of (137)Cs with limited transfer via the groundwater pathway. The model was also used to explore the potential impacts of soil organic matter (SOM) interactions on the mobility and bioavailability of (137)Cs in the soil-plant system. The simulation results for hypothetical organic soils with modified parameters of (137)Cs turnover revealed that the SOM-induced reduction of (137)Cs adsorption elevates the fraction of dissolved (137)Cs in the soil solution, thereby increasing the soil-to-plant transfer of (137)Cs without substantially altering the fractional distribution of (137)Cs in the soil. Slower fixation of (137)Cs on the flayed edge site of clay minerals and enhanced mobilization of the clay-fixed (137)Cs in organic-rich soils also appeared to elevate the soil-to-plant transfer of (137)Cs by increasing the fraction of the soil-adsorbed (exchangeable) (137)Cs. A substantial proportion (approximate 30%-60%) of (137)Cs in these organic-rich soils was transferred to layers deeper than 5cm decades later. These results suggested that SOM influences the behavior of (137)Cs in forests over a prolonged period through alterations of adsorption and fixation in the soil. PMID:26897402

  14. Spatial patterns of (137)Cs inventories and soil erosion from earth-banked terraces in the Yimeng Mountains, China.

    PubMed

    Zhang, Yunqi; Long, Yi; An, Juan; Yu, Xingxiu; Wang, Xiaoli

    2014-10-01

    The Yimeng Mountains is one of China's most susceptible regions to soil erosion. In this region, slopes are composed of granite- or gneiss-derived soils that are commonly cultivated using earth-banked terraces. Based on the (137)Cs measurement for nine reference cores, the present study analysed the spatial patterns of (137)Cs inventory and soil erosion using 105 sampling points in a seven-level earth-banked terrace system. The mean (137)Cs inventory, standard deviation, coefficient of variation, and allowable error for the nine reference cores were 987 Bq m(-2), 71 Bq m(-2), 7%, and 6%, respectively, values that may reflect the heterogeneity of the initial (137)Cs fallout deposit. Within each terrace, the (137)Cs inventory generally increases from the rear edge to the front edge, accompanied by a decrease in the erosion rate. This results from planation by tillage and rainfall runoff during the development of the earth-banked terraces. Across the entire seven-level terrace system, (137)Cs inventories decrease from the highest terrace downwards, but increase in the lower terraces, whereas erosion rate displays the opposite trend. These trends are the result of the combined effects of the earth-bank segmented hillslope, the limited protection of the earth banks, and rainfall runoff in combination with tillage. The high coefficients of variation of (137)Cs inventories for the 21 sampling rows, with a mean value of 44%, demonstrate the combined effects of variations in original microtopography, anthropogenic disturbance, the incohesive soils weathered from underlying granite, and the warm climate. Although earth-banked terraces can reduce soil erosion to some extent, the estimated erosion rates for the study area are still very high. PMID:24844614

  15. 137Cs in fungal sporocarps in relation to vegetation in a bog, pine swamp and forest along a transect.

    PubMed

    Vinichuk, M; Rosén, K; Dahlberg, A

    2013-01-01

    In this study, we estimated the relative importance of vegetation and fungi for radiocesium uptake and biological retention in adjacent bog, pine swamp, and forest. The measurements for (137)Cs activity concentration in sporocarps (i.e. fruitbodies of fungi) and vegetation along a bog to forest transect were combined with complementary published data to calculate estimates. Aboveground vegetation comprised 17.7% of the total fallout-derived radiocesium in the system in bog, 16.5% in pine swamp, and 40.6% in forest. In fungal sporocarps grown along a gradient, (137)Cs activity comprised <0.001% of the total radiocesium for peat bog, <0.02% for pine swamp, and 0.11% for forest. Total (137)Cs activity in sporocarps increased along the gradient due to increased production of sporocarps in the presence of trees from 0.006 (bog), 0.097 (pine swamp) and 0.67 (forest) g dwt m(-2). Based on calculation of the total vegetation biomass and through relationships between fungal biomass in sporocarps and as mycelia in soil, the total (137)Cs activity located in fungi was estimated as 0.1% in bog, 2% in pine swamp, and 11% in forest. An analysis of the time-dependency of (137)Cs in the sporocarps in forest between 1990 and 2011 suggested an ecological half-life for (137)Cs between 8 and 13 years. Although fungi comprised a relatively small fraction of the total radiocesium in the systems, its activity decreased slowly with time, and ecological residence time for (137)Cs in sporocarps of fungi was long, suggesting they will continue to contribute to the accumulation and cycling of this radionuclide in forest.

  16. Genotypic difference in (137)Cs accumulation and transfer from the contaminated field in Fukushima to azuki bean (Vigna angularis).

    PubMed

    Win, Khin Thuzar; Oo, Aung Zaw; Kojima, Katsuhiro; Salem, Djedidi; Yamaya, Hiroko; Bellingrath-Kimura, Sonoko Dorothea; Tomooka, Norihiko; Kaga, Akito; Ohkama-Ohtsu, Naoko; Yokoyama, Tadashi

    2016-07-01

    The screening of mini-core collection of azuki bean accessions (Vigna angularis (Willd.) Ohwi & Ohashi) for comparative uptake of (137)Cs in their edible portions was done in field trials on land contaminated by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Ninety seven azuki bean accessions including their wild relatives from a Japanese gene bank, were grown in a field in the Fukushima prefecture, which is located approximately 51 km north of FDNPP. The contamination level of the soil was 3665 ± 480 Bq kg(-1) dry weight ((137)Cs, average ± SD). The soil type comprised clay loam, where the sand: silt: clay proportion was 42:21:37. There was a significant varietal difference in the biomass production, radiocaesium accumulation and transfer factor (TF) of radiocaesium from the soil to edible portion. Under identical agricultural practice, the extent of (137)Cs accumulation by seeds differed between the accessions by as much as 10-fold. Inter-varietal variation was expressed at the ratio of the maximum to minimum observed (137)Cs transfer factor for seeds ranged from 0.092 to 0.009. The total biomass, time to flowering and maturity, and seed yield had negative relationship to (137)Cs activity concentration in seeds. The results suggest that certain variety/varieties of azuki bean which accumulated less (137)Cs in edible portion with preferable agronomic traits are suitable to reduce the (137)Cs accumulation in food chain on contaminated land. PMID:27105146

  17. Spatial patterns of (137)Cs inventories and soil erosion from earth-banked terraces in the Yimeng Mountains, China.

    PubMed

    Zhang, Yunqi; Long, Yi; An, Juan; Yu, Xingxiu; Wang, Xiaoli

    2014-10-01

    The Yimeng Mountains is one of China's most susceptible regions to soil erosion. In this region, slopes are composed of granite- or gneiss-derived soils that are commonly cultivated using earth-banked terraces. Based on the (137)Cs measurement for nine reference cores, the present study analysed the spatial patterns of (137)Cs inventory and soil erosion using 105 sampling points in a seven-level earth-banked terrace system. The mean (137)Cs inventory, standard deviation, coefficient of variation, and allowable error for the nine reference cores were 987 Bq m(-2), 71 Bq m(-2), 7%, and 6%, respectively, values that may reflect the heterogeneity of the initial (137)Cs fallout deposit. Within each terrace, the (137)Cs inventory generally increases from the rear edge to the front edge, accompanied by a decrease in the erosion rate. This results from planation by tillage and rainfall runoff during the development of the earth-banked terraces. Across the entire seven-level terrace system, (137)Cs inventories decrease from the highest terrace downwards, but increase in the lower terraces, whereas erosion rate displays the opposite trend. These trends are the result of the combined effects of the earth-bank segmented hillslope, the limited protection of the earth banks, and rainfall runoff in combination with tillage. The high coefficients of variation of (137)Cs inventories for the 21 sampling rows, with a mean value of 44%, demonstrate the combined effects of variations in original microtopography, anthropogenic disturbance, the incohesive soils weathered from underlying granite, and the warm climate. Although earth-banked terraces can reduce soil erosion to some extent, the estimated erosion rates for the study area are still very high.

  18. Potassium fertilization and (137)Cs transfer from soil to grass and barley in Sweden after the Chernobyl fallout.

    PubMed

    Rosén, K; Vinichuk, M

    2014-04-01

    Fertilization of soils contaminated by radionuclides with potassium (K) and its effect on (137)Cs transfer from soil to crops is well studied in field conditions; however experiments over many years are few. The effects of potassium fertilization on cesium-137 ((137)Cs) transfer to hay, pasture grass, and barley growing on organic rich soils and mineral sand and loam soils in a number of field experimental sites situated in different environments in Sweden are summarized and discussed. The basic experimental treatments were control (no K fertilizers were applied), 50, 100, and 200 kg K ha(-1). In the experiment, which lasted over 3-6 years, (137)Cs transfer factors in control treatments ranged between 0.0004 m(2) kg(-1) (barley grain on sand soil) and 0.07 m(2) kg(-1) (pasture grass on organic rich soil). Potassium application on soils with low clay content i.e. mineral sand and organic rich soils was effective at the 50-100 kg ha(-1) level. Application of 200 kg K ha(-1) resulted in a five-fold reduction in (137)Cs transfer for hay and up to four-fold for barley grain. The effects of potassium application were generally greater on sand than organic rich soil and were observed already in the first cut. After K application, the reduction in (137)Cs transfer to crops was correlated with (137)Cs:K ratios in plant material. Additional application of zeolite caused a 1.4 reduction of (137)Cs transfer to hay on sand and 1.8-fold reduction on organic rich soil; whereas, application of potash-magnesia and CaO had no effect.

  19. Pre- and post-accident (129)I and (137)Cs levels, and (129)I/(137)Cs ratios in soil near the Fukushima Dai-ichi Nuclear Power Plant, Japan.

    PubMed

    Matsunaka, Tetsuya; Sasa, Kimikazu; Sueki, Keisuke; Takahashi, Tsutomu; Satou, Yukihiko; Matsumura, Masumi; Kinoshita, Norikazu; Kitagawa, Jun-ichi; Matsuzaki, Hiroyuki

    2016-01-01

    To evaluate the deposition density and extent of subsurface infiltration of (129)I and (137)Cs in the restricted area that was highly contaminated by the accident of Fukushima Dai-ichi Nuclear Power Plant, cumulative inventories of (129)I and (137)Cs, concentrations of (129)I and (137)Cs, and (129)I/(137)Cs ratio in 30-cm-long soil columns were compared with pre-accident levels from the same area. The cores were collected before and after the accident from locations of S-1 (4 km west of FDNPP) and S-2 (8 km west of FDNPP). Deposition densities of (129)I and (137)Cs in the soil following the accident were 0.90-2.33 Bq m(-2) and 0.80-4.04 MBq m(-2), respectively, which were 14-39 and 320-510 times larger than the pre-accident levels of (129)I (59.3-63.3 mBq m(-2)) and (137)Cs (2.51-7.88 kBq m(-2)), respectively. Approximately 90% of accident-derived (129)I and (137)Cs deposited in the 30-cm soil cores was concentrated in the surface layer from 0 to 44-95 kg m(-2) of mass depth (0-4.3-6.2 cm depth) and from 0 to 16-25 kg m(-2) of mass depth (0-1.0-3.1 cm depth), respectively. The relaxation mass depths (h0) of 10.8-11.2 kg m(-2) for (129)I estimated in the previous study were larger than those of 8.1-10.6 kg m(-2) for (137)Cs at both sites, owing to the larger infiltration depth of radioiodine mainly by the gravitational water penetration in the surface soil in our study sites. Approximately 7-9% of the accident-derived (129)I was present in the lower layer from 44 to 100 kg m(-2) (4.3-8.6 cm depth) at S-1, and from 95 to 160 kg m(-2) (6.2-10.2 cm depth) at S-2. Approximately 1% of (137)Cs seems to infiltrate deeper than (129)I in the lower layer at each site in contrast to the surface layer. PMID:26492397

  20. Pre- and post-accident (129)I and (137)Cs levels, and (129)I/(137)Cs ratios in soil near the Fukushima Dai-ichi Nuclear Power Plant, Japan.

    PubMed

    Matsunaka, Tetsuya; Sasa, Kimikazu; Sueki, Keisuke; Takahashi, Tsutomu; Satou, Yukihiko; Matsumura, Masumi; Kinoshita, Norikazu; Kitagawa, Jun-ichi; Matsuzaki, Hiroyuki

    2016-01-01

    To evaluate the deposition density and extent of subsurface infiltration of (129)I and (137)Cs in the restricted area that was highly contaminated by the accident of Fukushima Dai-ichi Nuclear Power Plant, cumulative inventories of (129)I and (137)Cs, concentrations of (129)I and (137)Cs, and (129)I/(137)Cs ratio in 30-cm-long soil columns were compared with pre-accident levels from the same area. The cores were collected before and after the accident from locations of S-1 (4 km west of FDNPP) and S-2 (8 km west of FDNPP). Deposition densities of (129)I and (137)Cs in the soil following the accident were 0.90-2.33 Bq m(-2) and 0.80-4.04 MBq m(-2), respectively, which were 14-39 and 320-510 times larger than the pre-accident levels of (129)I (59.3-63.3 mBq m(-2)) and (137)Cs (2.51-7.88 kBq m(-2)), respectively. Approximately 90% of accident-derived (129)I and (137)Cs deposited in the 30-cm soil cores was concentrated in the surface layer from 0 to 44-95 kg m(-2) of mass depth (0-4.3-6.2 cm depth) and from 0 to 16-25 kg m(-2) of mass depth (0-1.0-3.1 cm depth), respectively. The relaxation mass depths (h0) of 10.8-11.2 kg m(-2) for (129)I estimated in the previous study were larger than those of 8.1-10.6 kg m(-2) for (137)Cs at both sites, owing to the larger infiltration depth of radioiodine mainly by the gravitational water penetration in the surface soil in our study sites. Approximately 7-9% of the accident-derived (129)I was present in the lower layer from 44 to 100 kg m(-2) (4.3-8.6 cm depth) at S-1, and from 95 to 160 kg m(-2) (6.2-10.2 cm depth) at S-2. Approximately 1% of (137)Cs seems to infiltrate deeper than (129)I in the lower layer at each site in contrast to the surface layer.

  1. (210)Po and (210)Pb in medicinal plants in the region of Karnataka, Southern India.

    PubMed

    Chandrashekara, K; Somashekarappa, H M

    2016-08-01

    The activity concentrations of naturally occurring radionuclides (210)Po and (210)Pb were estimated in some selected medicinal plants and soil samples of coastal Karnataka in India. The mean activity concentrations of (210)Po and (210)Pb varied in the range of 4.7-42.9 Bq kg(-1) (dry weight) and 36.1-124 Bq kg(-1) (dry weight) in the soil samples, and 3.3-63.7 Bq kg(-1) (dry weight) and 12.0-406 Bq kg(-1) (dry weight), in the medicinal plant samples, respectively. The plants, Ocimum sanctum L. and Plectranthus amboinicus (Lour.) Spreng had significantly higher activity concentrations of (210)Po and (210)Pb than other species sampled. In spite of disequilibrium between them, these two radionuclides were well correlated in both soil and medicinal plants. PMID:27155527

  2. Radioactivity of 210Pb in Japanese cigarettes and radiation dose from smoking inhalation.

    PubMed

    Sakoda, A; Fukao, K; Kawabe, A; Kataoka, T; Hanamoto, K; Yamaoka, K

    2012-06-01

    It is well known that cigarette tobaccos contain naturally occurring radioactive nuclides such as (210)Pb and (210)Po. In many countries, the radioactivity of tobaccos has been measured to estimate the effective dose from smoking inhalation. The present study covered 24 cigarette brands including the top 20 of sales in Japan between April 2008 and March 2009. The activity concentrations of (210)Pb were measured by gamma-ray spectrometry, and then those of its progeny ((210)Po) were evaluated assuming the radioactive equilibrium between the two nuclides. Their concentrations were in the range of 2-14 mBq cigarette(-1) with an arithmetic mean of 8±3 mBq cigarette(-1). The annual committed effective doses were also calculated, based on the scenario that a smoker consumes 20 cigarettes a day. The average doses from (210)Pb and (210)Po inhalations were 22±9 and 68±27 μSv y(-1), respectively.

  3. Rapid determination of (210)Pb and (210)Po in water and application to marine samples.

    PubMed

    Villa-Alfageme, M; Mas, J L; Hurtado-Bermudez, S; Masqué, P

    2016-11-01

    Measurement of radionuclides in marine samples, specifically radioactive pairs disequilibrium, has gained interest lately due to their ability to trace cutting edge biogeochemical processes. In this context, we developed a fast, direct method for determining (210)Pb and (210)Po water through the use of ultra low-level liquid scintillation counting and alpha-particle spectrometry respectively and through Eichrom Sr resins for the Po-Pb separation. For (210)Pb analysis, the method uses stable lead as a yield tracer measured by a robust ICP-MS technique, and (210)Po is determined through self-deposition using the conventional (209)Po yield tracer. The improvements of the method over other techniques are: a) the analysis can be completed within 6 days, simplifying other methods, b) very low limits of detection have been achieved -0.12 and 0.005mBqL(-1) for (210)Pb and (210)Po, respectively - and c) most of the method could be carried out in on-board analysis. We applied the method to different aqueous samples and specifically to marine samples. We determined (210)Pb and (210)Po in the dissolved fraction of Mediterranean Sea water and an estuary at the South-West of Spain. We found that it can be successfully employed to marine samples but we recommend to i) use a minimum of 20L water to measure the (210)Pb in the dissolved phase by LSC and lower volumes to measure total concentrations; ii) wait for (210)Pb and (210)Bi in secular equilibrium and measure the total spectrum to minimise the limit of detection and improve accuracy.

  4. Temporal variations of 7Be and 210Pb activity in aerosols at Xiamen, China

    NASA Astrophysics Data System (ADS)

    Huang, Dekun

    2016-04-01

    The radionuclides serve as powerful tracers to identify and quantify several atmospheric processes, such as source, transport and mixing of air masses, air masses exchanging between various atmospheric layers, residence times of atmospheric gasses and pollutants. 7Be and 210Pb activities in aerosols were measurement from October, 2013 to September, 2015 at Xiamen (24°26'7.44″N, 118°5'31.30″N) in South China. The activity of 7Be and 210Pb in aerosols from 2013 to 2015 in Xiamen ranged from 0.26 to 9.05 (mean:4.15) mBq m-3 and from 0.14 to 2.64 (mean:1.05) mBq m-3, respectively. The mean activity of 7Be was comparable with the activities of other places in the same latitude, while the mean activity of 210Pb was lower than the activity of the locations at high altitudes. The possible reason is that Xiamen is a coastal city located on southwest Pacific. The activities of 7Be and 210Pb had a commonly low value in summer (July-September) and a high value in autumn (October-December), it may be controlled by the rainfall. There is significant relationship between the monthly 210Pb activities and the concentration of PM 2.5 and PM 10. In contrast, monthly 7Be activities only show significant correlation with the concentration of PM 10, which implies that 7Be and 210Pb can be used to trace the different sources of the aerosols. And the dry 7Be depositional fluxes increased with latitude along the coast of China (R2=0.92, n=8).

  5. Rapid determination of (210)Pb and (210)Po in water and application to marine samples.

    PubMed

    Villa-Alfageme, M; Mas, J L; Hurtado-Bermudez, S; Masqué, P

    2016-11-01

    Measurement of radionuclides in marine samples, specifically radioactive pairs disequilibrium, has gained interest lately due to their ability to trace cutting edge biogeochemical processes. In this context, we developed a fast, direct method for determining (210)Pb and (210)Po water through the use of ultra low-level liquid scintillation counting and alpha-particle spectrometry respectively and through Eichrom Sr resins for the Po-Pb separation. For (210)Pb analysis, the method uses stable lead as a yield tracer measured by a robust ICP-MS technique, and (210)Po is determined through self-deposition using the conventional (209)Po yield tracer. The improvements of the method over other techniques are: a) the analysis can be completed within 6 days, simplifying other methods, b) very low limits of detection have been achieved -0.12 and 0.005mBqL(-1) for (210)Pb and (210)Po, respectively - and c) most of the method could be carried out in on-board analysis. We applied the method to different aqueous samples and specifically to marine samples. We determined (210)Pb and (210)Po in the dissolved fraction of Mediterranean Sea water and an estuary at the South-West of Spain. We found that it can be successfully employed to marine samples but we recommend to i) use a minimum of 20L water to measure the (210)Pb in the dissolved phase by LSC and lower volumes to measure total concentrations; ii) wait for (210)Pb and (210)Bi in secular equilibrium and measure the total spectrum to minimise the limit of detection and improve accuracy. PMID:27591584

  6. {sup 40}K, {sup 115}Cs and {sup 226}Ra Soil and Plant Content in Seminatural Grasslands of Central Argentina

    SciTech Connect

    Ayub, J. Juri; Velasco, R. H.; Rizzotto, M.; Quintana, E.; Aguiar, J.

    2008-08-07

    Activity concentrations of {sup 40}K, {sup 226}Ra and {sup 137}Cs have been analyzed in soil and plant samples, collected in permanent grassland in central Argentina. Two near areas (A1 and A2) under field conditions with soil undisturbed at least in the last four decades were selected. For each of the three studied radionuclides we do not find differences in the inventories between both areas. The inventories range from 143 kBq m{sup -2} to 197 kBq m{sup -2} for {sup 40}K and from 13 kBq m{sup -2} to 18 kBq m{sup -2} for {sup 226}Ra. The vertical distributions of {sup 40}K and {sup 226}Ra are uniform through de soil profile. For {sup 137}Cs the inventories range from 0.33 kBq m{sup -2} to 0.73 kBq m{sup -2}. In spite of {sup 137}Cs inventories are similar in both areas the distribution through vertical profile is different. {sup 137}Cs activity concentration has a maximum for layers 5-10 cm depth in A1 and 10-15 cm depth in A2. For deeper layers both areas show similar activity concentrations. The diffusion coefficient (D{sub s}) and convection velocity (v{sub s}) are estimated with a convection-diffusion model. D{sub s} values are in the range reported in the bibliography, while v{sub s} values are one order of magnitude higher. After 40 years most {sup 137}Cs fallout is still in the layer 10-15 cm depth. The great penetration of {sup 137}Cs (25 cm) in these soils may be the result of a high sand and low fine materials content. {sup 137}Cs and {sup 226}Ra were not detected in grass samples. Activity concentration of {sup 40}K in vegetal samples ranges from 116 Bq kg{sup -1} to 613 Bq kg{sup -1}. The TF values obtained for {sup 40}K show a lognormal distribution and ranges from 0.05 to 0.42.

  7. A comparison of {sup 137}Cs radioactivity in localized evergreen and deciduous plant species

    SciTech Connect

    Rangel, R.C.; Schlapper, G.A.; McLain, M.E.; Pitt, W.W.

    1996-06-01

    A vegetation study at the Comanche Steam Electric Station (CPSES) in Texas was conducted in 1991 and 1992. The CPSES is a commercial nuclear power plant. The CPSES environmental monitoring program collects broadleaf vegetation samples as per the Nuclear Regulatory Commission (NRC). Broadleaf trees are scarce in the area because of local climate, soils, and geology. The dominate tree is an evergreen juniper. Few broadleaves are available during winter for sampling. This study compared the environmental {sup 137}C s radioactivity between broadleaf and evergreen foliage. The study`s objective was to determine if {sup 137}C s radioactivity is statistically the same in the deciduous and evergreen vegetation. Radioactivity from the same statistical population could allow the sampling program to collect evergreen (junipers) foliage. Broadleaf and evergreen tree leaf samples were collected on and off the CPSES area. Gamma-ray spectrometry was performed on the samples to measure {sup 137}Cs radioactivity. The means of the {sup 137}Cs concentrations in broadleaf and evergreen foliage samples were found to be statistically the same and therefore from the same population. This study`s conclusion is that evergreen leaves from juniper trees can be used to supplement and/or substitute for the broadleaf samples currently collected. This change in foliage collection, if approved by the NRC, would allow the CPSES to better satisfy its environmental sampling regulatory requirements.

  8. {sup 137}Cs elimination by chronically-contaminated largemouth bass (Micropterus salmoides)

    SciTech Connect

    Peters, E.L.; Newman, M.C.

    1999-03-01

    The temperature-dependent {sup 137}Cs biological half-times (T{sub b}) of lifetime-exposed largemouth bass (Micropterus salmoides) from a nuclear cooling reservoir at the US Department of Energy`s Savannah River Site were calculated from whole-body measurements of live fish and compared with literature records for acutely and chronically-contaminated fish. The T{sub b}`s of the bass averaged 322 d, 225 d, and 140 d at 15, 20, and 26 C, respectively. These mean T{sub b}`s were 1.7 to 2.5 times longer than would be expected for acutely contaminated fish, and 1.2 to 1.8 times longer than those predicted for fish at steady-state with their environment according to recent models. This slower elimination did not appear to result from slower elimination from skeletal muscle compared with other soft tissues, in that the muscle to whole-body {sup 137}Cs concentration ratios after the elimination period were similar to those of freshly-caught bass. Their results suggested that elimination rates estimated from the terminal elimination components of acutely-dosed fish may not reflect the elimination rates of fish exposed to contaminants throughout their lifetime, even when care is taken to allow sufficient time for absorption of the dose.

  9. Activity ratios of 137Cs, 90Sr and 239+240Pu in environmental samples.

    PubMed

    Bossew, P; Lettner, H; Hubmer, A; Erlinger, C; Gastberger, M

    2007-01-01

    Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as 137Cs, 90Sr and 239+240Pu. In environmental samples, 137Cs and 239+240Pu can be divided into the contributions of either source, if also the isotopes 134Cs and 238Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for 90Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition. In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu. PMID:17407799

  10. Estimation of sedimentation rate in the Middle and South Adriatic Sea using 137Cs.

    PubMed

    Petrinec, Branko; Franic, Zdenko; Ilijanic, Nikolina; Miko, Slobodan; Strok, Marko; Smodis, Borut

    2012-08-01

    (137)Cs activity concentrations were studied in the sediment profiles collected at five locations in the Middle and South Adriatic. In the sediment profiles collected from the South Adriatic Pit, the deepest part of the Adriatic Sea, two (137)Cs peaks were identified. The peak in the deeper layer was attributed to the period of intensive atmospheric nuclear weapon tests (early 1960s), and the other to the Chernobyl nuclear accident (1986). Those peaks could be used to estimate sedimentation rates by relating them to the respective time periods. Grain-size analysis showed no changes in vertical distribution through the depth of the sediment profile, and these results indicate uniform sedimentation, as is expected in deeper marine environments. It was not possible to identify respective peaks on more shallow locations due to disturbance of the seabed either by trawlers (locations PalagruŽa and Jabuka) or by river sediment (location Albania). The highest sedimentation rates were found in Albania (∼4 mm y(-1)) and Jabuka (3.1 mm y(-1)). For PalagruŽa, the sedimentation rate was estimated to be 1.8 mm y(-1), similar to the South Adriatic Pit where the sedimentation rate was estimated to be 1.8±0.5 mm y(-1). Low sedimentation rates found for the Middle and South Adriatic Sea are consistent with previously reported results for the rest of the Mediterranean.

  11. Interactions of 57Co, 85Sr and 137Cs with peat under acidic precipitation conditions.

    PubMed

    Sanchez, A L; Schell, W R; Thomas, E D

    1988-03-01

    Following the burial of low-level wastes in nuclear waste repositories, the interactions of radionuclides with surrounding soil infiltrated by acid precipitation could cause radionuclide migration and transport into nearby wells. To evaluate this migration through organically rich soil in the unsaturated zone, we measured sorption and desorption distribution ratios (Rd) of 57Co, 85Sr and 137Cs onto peat at pH 4. Peat samples rich in organic C showed relatively higher sorption Rd values for 57Co and 85Sr compared to soil samples with less organic C. The sorption and desorption Rd values for these radionuclides are similar, indicating the reversibility of the sorption process. The measurements suggest the importance of organic complexes for the retention of these radionuclides at the pH range (pH 4), where hydrolysis of the metals is not important and sorption is expected to be low. Cesium-137, on the other hand, appears to be associated more strongly with inorganic components of the soil samples, with its Rd value significantly higher in the peat material containing less organic C. The 137Cs desorption Rd on the same peat sample is also comparable to the sorption Rd indicating equilibrium. Both the organic and inorganic components of peat are thus able to retard the migration of radionuclides which may be found in nuclear waste repositories. The design of such a repository may be improved using a peat barrier to restrict radionuclide migration.

  12. Monte Carlo-based investigation of water-equivalence of solid phantoms at (137)Cs energy.

    PubMed

    Vishwakarma, Ramkrushna S; Selvam, T Palani; Sahoo, Sridhar; Mishra, Subhalaxmi; Chourasiya, Ghanshyam

    2013-10-01

    Investigation of solid phantom materials such as solid water, virtual water, plastic water, RW1, polystyrene, and polymethylmethacrylate (PMMA) for their equivalence to liquid water at (137)Cs energy (photon energy of 662 keV) under full scatter conditions is carried out using the EGSnrc Monte Carlo code system. Monte Carlo-based EGSnrc code system was used in the work to calculate distance-dependent phantom scatter corrections. The study also includes separation of primary and scattered dose components. Monte Carlo simulations are carried out using primary particle histories up to 5 × 10(9) to attain less than 0.3% statistical uncertainties in the estimation of dose. Water equivalence of various solid phantoms such as solid water, virtual water, RW1, PMMA, polystyrene, and plastic water materials are investigated at (137)Cs energy under full scatter conditions. The investigation reveals that solid water, virtual water, and RW1 phantoms are water equivalent up to 15 cm from the source. Phantom materials such as plastic water, PMMA, and polystyrene phantom materials are water equivalent up to 10 cm. At 15 cm from the source, the phantom scatter corrections are 1.035, 1.050, and 0.949 for the phantoms PMMA, plastic water, and polystyrene, respectively.

  13. Removal of 137Cs from Dissolved Hanford Tank Saltcake by Treatment with IE-911

    SciTech Connect

    Rapko, Brian M. ); Sinkov, Serguei I. ); Levitskaia, Tatiana G. )

    2003-04-10

    The U.S. Department of Energy's Richland Operations Office plans to accelerate the cleanup of the Hanford Site. Testing new technology for the accelerated cleanup will require dissolved saltcake from single-shell tanks. However, the 137Cs will need to be removed from the saltcake to alleviate radiation hazards. A saltcake composite constructed from archived samples from Hanford Single Shell Tanks 241-S-101, 241-S-109, 241-S-110, 241-S-111, 241-U-106, and 241-U-109 was dissolved in water, adjusted to 5 M Na, and transferred from the 222-S building to the Radiochemical Processing Laboratory (RPL). At the RPL, the approximately 5.5 liters of solution was passed through a 0.2-micron polyethersulfone filter, collected, and homogenized. The filtered solution then was passed through an ion exchange column containing approximately 150 mL IONSIV IE-911, an engineered form of crystalline silicotitanate available from UOP, at approximately 200 mL/hour in a continuous operation until all of the feed solution had been run through the column. An analysis of the 137Cs concentrations in the initial feed solution and combined column effluent indicates that> 99.999 percent of the Cs in the feed solution was removed by this operation. This report describes the Cs-depletion operations together with a partial analysis of the as-received solution and a more extensive characterization of the Cs-depleted solution.

  14. Removal of 137-Cs from Dissolved Hanford Tank Saltcake by Treatment with IE-911

    SciTech Connect

    Rapko, Brian M.; Sinkov, Sergei I.; Levitskaia, Tatiana G.

    2003-12-09

    The U.S. Department of Energy’s Richland Operations Office plans to accelerate the cleanup of the Hanford Site. Testing new technology for the accelerated cleanup will require dissolved saltcake from single-shell tanks. However, the 137Cs will need to be removed from the saltcake to alleviate radiation hazards. A saltcake composite constructed from archived samples from Hanford Site single-shell tanks 241-S-101, 241-S-109, 241-S-110, 241-S-111, 241-U-106, and 241-U-109 was dissolved in water, adjusted to 5 M Na, and transferred from the 222-S Laboratory to the Radiochemical Processing Laboratory (RPL). At the RPL, the approximately 5.5 liters of solution was passed through a 0.2-micron polyethersulfone filter, collected, and homogenized. The filtered solution then was passed through an ion exchange column containing approximately 150 mL IONSIV® IE-911, an engineered form of crystalline silicotitanate available from UOP, at approximately 200 mL/hour in a continuous operation until all of the feed solution had been run through the column. An analysis of the 137Cs concentrations in the initial feed solution and combined column effluent indicates that > 99.999 percent of the Cs in the feed solution was removed by this operation. PNNR

  15. {sup 210}Po and {sup 210}Pb in Forest Soil and in Wild Berries in Finland

    SciTech Connect

    Vaaramaa, Kaisa; Lehto, Jukka; Solatie, Dina; Aro, Lasse

    2008-08-07

    The behaviour of {sup 210}Po and {sup 210}Pb was investigated in forests in the Southern Finland site and in the Northern Finland site. Sampling sites were in Scots pine (Pinus sylvestris) forests. Maximum activities of {sup 210}Po and {sup 210}Pb in soil columns were found in organic layers. According to preliminary results of wild berry samples, the lowest {sup 210}Po concentrations were found in berries. The highest concentration of {sup 210}Po was found in stems of the blueberry (Vaccinium myrtillus) and the lingonberry (Vaccinium vitis-idaea) samples.

  16. Measurement of liquid scintillation sources of (210)Pb obtained from (222)Rn decay.

    PubMed

    Antohe, A; Sahagia, M; Luca, A; Ioan, M-R; Ivan, C

    2016-03-01

    Liquid scintillation samples were filled with (222)Rn and the activity was measured with good precision after reaching the secular equilibrium with the progeny (218)Po, (214)Pb, (214)Bi and (214)Po. After decay of most of (222)Rn activity, the samples contain (210)Pb and progeny. The activities of (210)Pb and progeny can be calculated as a function of time using the initial (222)Rn activity. The samples were measured in a TDCR counter and the experimentally determined counting efficiencies are in accordance with previously published results.

  17. Measurement of liquid scintillation sources of (210)Pb obtained from (222)Rn decay.

    PubMed

    Antohe, A; Sahagia, M; Luca, A; Ioan, M-R; Ivan, C

    2016-03-01

    Liquid scintillation samples were filled with (222)Rn and the activity was measured with good precision after reaching the secular equilibrium with the progeny (218)Po, (214)Pb, (214)Bi and (214)Po. After decay of most of (222)Rn activity, the samples contain (210)Pb and progeny. The activities of (210)Pb and progeny can be calculated as a function of time using the initial (222)Rn activity. The samples were measured in a TDCR counter and the experimentally determined counting efficiencies are in accordance with previously published results. PMID:26725538

  18. 137Cs in recent tsunami deposits - a potential tracer of selective tsunami sediment entrainment?

    NASA Astrophysics Data System (ADS)

    Spiske, M.; Bahlburg, H.; Suckow, A.

    2012-12-01

    The tsunami of 27 February, 2010 affected a 600 km long stretch of the central Chilean coastline. We documented the tsunami deposits 4 months after the event in 2010 and two years later in 2012. The broad coastal plain at La Trinchera was inundated ca. 430 m inland and up to 8 m above sea level. A ca. 10 cm thick layer of tsunami sand was deposited on top of marsh sediments. A comparison of this layer in 2010 and 2012 reveals a change in the relative mineral composition and related grain size. In 2010 the layer consisted of 90-93% heavy minerals, 1-4% quartz, 2-3% organics and 1-3% feldspar. In 2012 the relative abundances changed to 63-76% heavy minerals, 10-12% quartz, 16-20% organics and 5-7% feldspar, as a result of the erosion of parts of the finer grained heavy minerals. Furthermore, the thickness decreased to ca. 8 cm. The concentration of the artificial radionuclide 137Cs was recorded using high-resolution gamma-spectrometry. Especially in the northern hemisphere, 137Cs is a tracer for radioactive fallout emitted mainly during nuclear tests in the 1950s to 1960s, peaking around 1963, or nuclear bombing and accidents. In contrast, Cs-concentrations in the southern hemisphere are about four times lower (<1 Bq/kg). Generally, the Cs-signal in terrestrial sediments is higher compared to marine deposits due to Cs-dilution in sea water. For recent (younger than ca. 60 years) onshore tsunami sediments, a mixed Cs-signal is expected because a tsunami can entrain sediments from different depositional environments and different stratigraphic age levels. At La Trinchera, gamma-spectrometry revealed a 137Cs-content of 0.5 Bq/kg for the lower ca. 5 cm of the tsunami layer. The 137Cs-concentration of the upper 5 cm was below the detection limit of 0.1 Bq/kg. Even though the tsunami layer appears to be structureless, the Cs-content may help to distinguish between two distinctive depositional units within the layer. We suggest that the lower part represents reworked

  19. Post-Chernobyl 137Cs in the atmosphere of Thessaloniki: a consequence of the financial crisis in Greece.

    PubMed

    Stoulos, S; Ioannidou, A; Vagena, E; Koseoglou, P; Manolopoulou, M

    2014-02-01

    The background radiation level of (137)Cs at the urban atmosphere of Thessaloniki has been increased during the recent decade only due to the Fukushima accident fallout. Since then, no other signal of (137)Cs was observed until the winter period of 2013, when slightly elevated (137)Cs concentrations were measured. The (137)Cs signals observed were up to 12 μBq m(-3), mainly during holidays and weekends followed by lower or even non-detectable activities in the next working days. Those episodes are attributed to the increase of biomass products combustion for residential heating as this year the tax of oil for heating was drastically raised as a consequence of the financial crisis. A preliminary survey of various wood products as well as of bottom ashes from different domestic burning devices is presented. (137)Cs concentrations up to 11 Bq kg(-1) were measured in wood products and up to 500 Bq kg(-1) in ash samples. PMID:24316685

  20. Post-Chernobyl 137Cs in the atmosphere of Thessaloniki: a consequence of the financial crisis in Greece.

    PubMed

    Stoulos, S; Ioannidou, A; Vagena, E; Koseoglou, P; Manolopoulou, M

    2014-02-01

    The background radiation level of (137)Cs at the urban atmosphere of Thessaloniki has been increased during the recent decade only due to the Fukushima accident fallout. Since then, no other signal of (137)Cs was observed until the winter period of 2013, when slightly elevated (137)Cs concentrations were measured. The (137)Cs signals observed were up to 12 μBq m(-3), mainly during holidays and weekends followed by lower or even non-detectable activities in the next working days. Those episodes are attributed to the increase of biomass products combustion for residential heating as this year the tax of oil for heating was drastically raised as a consequence of the financial crisis. A preliminary survey of various wood products as well as of bottom ashes from different domestic burning devices is presented. (137)Cs concentrations up to 11 Bq kg(-1) were measured in wood products and up to 500 Bq kg(-1) in ash samples.

  1. Use of (137)Cs technique for soil erosion study in the agricultural region of Casablanca in Morocco.

    PubMed

    Nouira, A; Sayouty, E H; Benmansour, M

    2003-01-01

    Accelerated erosion and soil degradation currently cause serious problems to the Oued El Maleh basin (Morocco). Furthermore, there is still only limited information on rates of soil loss for optimising strategies for soil conservation. In the present study we have used the (137)Cs technique to assess the soil erosion rates on an agricultural land in Oued el Maleh basin near Casablanca (Morocco). A small representative agricultural field was selected to investigate the soil degradation required by soil managers in this region. The transect approach was applied for sampling to identify the spatial redistribution of (137)Cs. The spatial variability of (137)Cs inventory has provided evidence of the importance of tillage process and the human effects on the redistribution of (137)Cs. The mean (137)Cs inventory was found about 842 Bq m(-2), this value corresponds to an erosion rate of 82 tha(-1) yr(-1) by applying simplified mass balance model in a preliminary estimation. When data on site characteristics were available, the refined mass balance model was applied to highlight the contribution of tillage effect in soil redistribution. The erosion rate was estimated about 50 tha(-1) yr(-1). The aspects related to the sampling procedures and the models for calculation of erosion rates are discussed.

  2. Comparison of the post-Chernobyl 137Cs contamination of mushrooms from eastern Europe, Sweden, and North America.

    PubMed Central

    Smith, M L; Taylor, H W; Sharma, H D

    1993-01-01

    A comparison was made of 134Cs and 137Cs contamination in fungi from eastern Europe and eastern North America. Mean activities of 25 Ukrainian, 6 Swedish, and 10 North American collections were 4,660, 9,750, and 205 Bq/kg (dry weight), respectively. Additional measurements were made on samples from the Moscow, southern Belarus, and Yugoslavia/Bulgaria regions. Activity values were found to vary by several orders of magnitude within all geographic areas, even for the same mushroom species. Significantly higher specific activities were observed in mycorrhizal species than in saprophytic and parasitic fungi. Unfortunately, many of the European mycorrhizal species considered as prized edibles contained unacceptably high levels of 137Cs (> 1,000 Bq/kg [dry weight]) and should be used sparingly as food. By contrast, no mushrooms collected in Ontario or northern Michigan exceeded 1,000 Bq of 137Cs per kg (dry weight). The excessive 137Cs contamination was evident in mushrooms from areas that had substantial fallout from the 1986 accident in reactor 4 at the Chernobyl nuclear power station. However, observations suggest that about 20% of the 137Cs in eastern Europe (Moscow area, Belarus, and Ukraine) is of non-Chernobyl origin. PMID:8439144

  3. Comparison of the post-Chernobyl [sup 137]Cs contamination of mushrooms from eastern Europe, Sweden, and North America

    SciTech Connect

    Smith, M.L.; Taylor, H.W.; Sharma, H.D. )

    1993-01-01

    A comparison was made of 134Cs and 137Cs contamination in fungi from eastern Europe and eastern North America. Mean activities of 25 Ukrainian, 6 Swedish, and 10 North American collections were 4,660, 9,750, and 205 Bq/kg (dry weight), respectively. Additional measurements were made on samples from the Moscow, southern Belarus, and Yugoslavia/Bulgaria regions. Activity values were found to vary by several orders of magnitude within all geographic areas, even for the same mushroom species. Significantly higher specific activities were observed in mycorrhizal species than in saprophytic and parasitic fungi. Unfortunately, many of the European mycorrhizal species considered as prized edibles contained unacceptably high levels of 137Cs (> 1,000 Bq/kg [dry weight]) and should be used sparingly as food. By contrast, no mushrooms collected in Ontario or northern Michigan exceeded 1,000 Bq of 137Cs per kg (dry weight). The excessive 137Cs contamination was evident in mushrooms from areas that had substantial fallout from the 1986 accident in reactor 4 at the Chernobyl nuclear power station. However, observations suggest that about 20% of the 137Cs in eastern Europe (Moscow area, Belarus, and Ukraine) is of non-Chernobyl origin.

  4. Geographical trends in 137Cs fallout from the Chernobyl accident and leaching from natural surface soil in Norway.

    PubMed

    Gjelsvik, Runhild; Steinnes, Eiliv

    2013-12-01

    In order to follow the turnover of (137)Cs in natural soils and estimate future trends in exposure of livestock, samples of natural surface soils were collected at 0-3 cm depth at 464 sites in 1995 and 463 sites in 2005 covering the country. In both cases the geographical pattern observed was similar to the original distribution from 1986, but the decline of (137)Cs activity in the surface soil was not the same everywhere. In 1995 the (137)Cs reduction since 1986 was found to be considerably greater in coastal areas than farther inland. The main reason for this appears to be the much greater deposition of marine cations such as Mg(2+) and Na(+) in the coastal areas, replacing Cs ions fixed on soil particle surfaces. This cation exchange appeared to be particularly strong near the southern coast where deposition of NH4(+) from transboundary air pollution is evident in addition to the marine cations. During 1995-2005 the (137)Cs decline in the surface soil was more uniform over the country than in the preceding 10-year period but still significantly higher in coastal areas than inland. Differences in precipitation chemistry may have influenced the uptake of (137)Cs in terrestrial food chains.

  5. (135)Cs/(137)Cs isotopic ratio as a new tracer of radiocesium released from the Fukushima nuclear accident.

    PubMed

    Zheng, Jian; Tagami, Keiko; Bu, Wenting; Uchida, Shigeo; Watanabe, Yoshito; Kubota, Yoshihisa; Fuma, Shoichi; Ihara, Sadao

    2014-05-20

    Since the Fukushima Daiichi nuclear power plant (FDNPP) accident in 2011, intensive studies of the distribution of released fission products, in particular (134)Cs and (137)Cs, in the environment have been conducted. However, the release sources, that is, the damaged reactors or the spent fuel pools, have not been identified, which resulted in great variation in the estimated amounts of (137)Cs released. Here, we investigated heavily contaminated environmental samples (litter, lichen, and soil) collected from Fukushima forests for the long-lived (135)Cs (half-life of 2 × 10(6) years), which is usually difficult to measure using decay-counting techniques. Using a newly developed triple-quadrupole inductively coupled plasma tandem mass spectrometry method, we analyzed the (135)Cs/(137)Cs isotopic ratio of the FDNPP-released radiocesium in environmental samples. We demonstrated that radiocesium was mainly released from the Unit 2 reactor. Considering the fact that the widely used tracer for the released Fukushima accident-sourced radiocesium in the environment, the (134)Cs/(137)Cs activity ratio, will become unavailable in the near future because of the short half-life of (134)Cs (2.06 years), the (135)Cs/(137)Cs isotopic ratio can be considered as a new tracer for source identification and long-term estimation of the mobility of released radiocesium in the environment.

  6. Porous three-dimensional graphene foam/Prussian blue composite for efficient removal of radioactive (137)Cs.

    PubMed

    Jang, Sung-Chan; Haldorai, Yuvaraj; Lee, Go-Woon; Hwang, Seung-Kyu; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

    2015-12-16

    In this study, a simple one-step hydrothermal reaction is developed to prepare composite based on Prussian blue (PB)/reduced graphene oxide foam (RGOF) for efficient removal of radioactive cesium ((137)Cs) from contaminated water. Scanning electron microscopy and transmission electron microscopy show that cubic PB nanoparticles are decorated on the RGO surface. Owing to the combined benefits of RGOF and PB, the composite shows excellent removal efficiency (99.5%) of (137)Cs from the contaminated water. The maximum adsorption capacity is calculated to be 18.67 mg/g. An adsorption isotherm fit-well the Langmuir model with a linear regression correlation value of 0.97. This type of composite is believed to hold great promise for the clean-up of (137)Cs from contaminated water around nuclear plants and/or after nuclear accidents.

  7. The effect of organic amendment on potential mobility and bioavailability of 137Cs and 60Co in tropical soils.

    PubMed

    Wasserman, M A; Bartoly, F; Portilho, A P; Rochedo, E R R; Viana, A G; Pérez, D V; Conti, C C

    2008-03-01

    In this work the role of organic matter in the potential mobility and bioavailability of 137Cs and 60Co in Brazilian soil was investigated. Radish was cultivated in pots containing the top layer (0-20 cm) of a Histosol, Ferralsol and Nitisol spiked with 137Cs and 60Co. In the case of the Ferralsol and Nitisol samples, besides the control, two different rates of organic amendments were used. In these soils, a sequential extraction protocol was used to identify the main soil compartments that could be responsible for the variation of transfer factor values. Our results indicate that organic amendment could be suggested as a practical countermeasure for 137Cs and 60Co contamination, since it reduces bioavailability of radionuclides and, consequently, soil to plant transfer factor values by almost one order of magnitude in a short period of time.

  8. Porous three-dimensional graphene foam/Prussian blue composite for efficient removal of radioactive 137Cs

    NASA Astrophysics Data System (ADS)

    Jang, Sung-Chan; Haldorai, Yuvaraj; Lee, Go-Woon; Hwang, Seung-Kyu; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

    2015-12-01

    In this study, a simple one-step hydrothermal reaction is developed to prepare composite based on Prussian blue (PB)/reduced graphene oxide foam (RGOF) for efficient removal of radioactive cesium (137Cs) from contaminated water. Scanning electron microscopy and transmission electron microscopy show that cubic PB nanoparticles are decorated on the RGO surface. Owing to the combined benefits of RGOF and PB, the composite shows excellent removal efficiency (99.5%) of 137Cs from the contaminated water. The maximum adsorption capacity is calculated to be 18.67 mg/g. An adsorption isotherm fit-well the Langmuir model with a linear regression correlation value of 0.97. This type of composite is believed to hold great promise for the clean-up of 137Cs from contaminated water around nuclear plants and/or after nuclear accidents.

  9. Porous three-dimensional graphene foam/Prussian blue composite for efficient removal of radioactive 137Cs

    PubMed Central

    Jang, Sung-Chan; Haldorai, Yuvaraj; Lee, Go-Woon; Hwang, Seung-Kyu; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

    2015-01-01

    In this study, a simple one-step hydrothermal reaction is developed to prepare composite based on Prussian blue (PB)/reduced graphene oxide foam (RGOF) for efficient removal of radioactive cesium (137Cs) from contaminated water. Scanning electron microscopy and transmission electron microscopy show that cubic PB nanoparticles are decorated on the RGO surface. Owing to the combined benefits of RGOF and PB, the composite shows excellent removal efficiency (99.5%) of 137Cs from the contaminated water. The maximum adsorption capacity is calculated to be 18.67 mg/g. An adsorption isotherm fit-well the Langmuir model with a linear regression correlation value of 0.97. This type of composite is believed to hold great promise for the clean-up of 137Cs from contaminated water around nuclear plants and/or after nuclear accidents. PMID:26670798

  10. Prediction of groundwater contamination with 137Cs and 131I from the Fukushima nuclear accident in the Kanto district.

    PubMed

    Ohta, Tomoko; Mahara, Yasunori; Kubota, Takumi; Fukutani, Satoshi; Fujiwara, Keiko; Takamiya, Koichi; Yoshinaga, Hisao; Mizuochi, Hiroyuki; Igarashi, Toshifumi

    2012-09-01

    We measured the concentrations of (131)I, (134)Cs, and (137)Cs released from the Fukushima nuclear accident in soil and rainwater samples collected March 30-31, 2011, in Ibaraki Prefecture, Kanto district, bordering Fukushima Prefecture to the south. Column experiments revealed that all (131)I in rainwater samples was adsorbed onto an anion-exchange resin. However, 30% of (131)I was not retained by the resin after it passed through a soil layer, suggesting that a portion of (131)I became bound to organic matter from the soil. The (137)Cs migration rate was estimated to be approximately 0.6 mm/y in the Kanto area, which indicates that contamination of groundwater by (137)Cs is not likely to occur in rainwater infiltrating into the surface soil after the Fukushima accident.

  11. Porous three-dimensional graphene foam/Prussian blue composite for efficient removal of radioactive (137)Cs.

    PubMed

    Jang, Sung-Chan; Haldorai, Yuvaraj; Lee, Go-Woon; Hwang, Seung-Kyu; Han, Young-Kyu; Roh, Changhyun; Huh, Yun Suk

    2015-01-01

    In this study, a simple one-step hydrothermal reaction is developed to prepare composite based on Prussian blue (PB)/reduced graphene oxide foam (RGOF) for efficient removal of radioactive cesium ((137)Cs) from contaminated water. Scanning electron microscopy and transmission electron microscopy show that cubic PB nanoparticles are decorated on the RGO surface. Owing to the combined benefits of RGOF and PB, the composite shows excellent removal efficiency (99.5%) of (137)Cs from the contaminated water. The maximum adsorption capacity is calculated to be 18.67 mg/g. An adsorption isotherm fit-well the Langmuir model with a linear regression correlation value of 0.97. This type of composite is believed to hold great promise for the clean-up of (137)Cs from contaminated water around nuclear plants and/or after nuclear accidents. PMID:26670798

  12. One-year, regional-scale simulation of 137Cs radioactivity in the ocean following the Fukushima Dai-ichi Nuclear Power Plant accident

    NASA Astrophysics Data System (ADS)

    Tsumune, D.; Tsubono, T.; Aoyama, M.; Uematsu, M.; Misumi, K.; Maeda, Y.; Yoshida, Y.; Hayami, H.

    2013-08-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant following the Great East Japan Earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways: direct release from the accident site and atmospheric deposition. A 1 yr, regional-scale simulation of 137Cs activity in the ocean offshore of Fukushima was carried out, the sources of radioactivity being direct release, atmospheric deposition, and the inflow of 137Cs deposited into the ocean by atmospheric deposition outside the domain of the model. Direct releases of 137Cs were estimated for 1 yr after the accident by comparing simulated results and measured activities adjacent to the accident site. The contributions of each source were estimated by analysis of 131I/137Cs and 134Cs/137Cs activity ratios and comparisons between simulated results and measured activities of 137Cs. The estimated total amounts of directly released 131I, 137Cs, and 137Cs were 11.1 ± 2.2 PBq, 3.5 ± 0.7 PBq, and 3.6 ± 0.7 PBq, respectively. Simulated 137Cs activities attributable to direct release were in good agreement with measured 137Cs activities not only adjacent to the accident site, but also in a wide area in the model domain, therefore this implies that the estimated direct release rate was reasonable. Employment of improved nudging data by JCOPE2 improved both the offshore transport result and the reproducibility of 137Cs activities 30 km offshore. On the other hand, simulated 137Cs activities attributable to atmospheric deposition were low compared to measured activities. The rate of atmospheric deposition into the ocean was underestimated because of a lack of measurements of deposition into the ocean when atmospheric deposition rates were being estimated. Simulated 137Cs activities attributable to the inflow of 137Cs deposited into the ocean outside the domain of the model were in good agreement with measured activities in the open ocean within the model

  13. Determining floodplain sedimentation rates using 137Cs in a low fallout environment dominated by channel- and cultivation-derived sediment inputs, central Queensland, Australia.

    PubMed

    Hughes, Andrew O; Olley, Jon M; Croke, Jacky C; Webster, Ian T

    2009-10-01

    Fallout (137)Cs has been widely used to determine floodplain sedimentation rates in temperate environments, particularly in the northern hemisphere. Its application in low fallout, tropical environments in the southern hemisphere has been limited. In this study we assess the utility of (137)Cs for determining rates of floodplain sedimentation in a dry-tropical catchment in central Queensland, Australia. Floodplain and reference site cores were analysed in two centimetre increments, depth profiles were produced and total (137)Cs inventories calculated from the detailed profile data. Information on the rates of (137)Cs migration through local soils was obtained from the reference site soil cores. This data was used in an advection-diffusion model to account of (137)Cs mobility in floodplain sediment cores. This allowed sedimentation rates to be determined without the first year of detection for (137)Cs being known and without having to assume that (137)Cs remains immobile following deposition. Caesium-137 depth profiles in this environment are demonstrated to be an effective way of determining floodplain sedimentation rates. The total (137)Cs inventory approach was found to be less successful, with only one of the three sites analysed being in unequivocal agreement with the depth profile results. The input of sediment from catchment sources that have little, or no, (137)Cs attached results in true depositional sites having total inventories that are not significantly different from those of undisturbed reference sites.

  14. 137Cs(90Sr) and Pu isotopes in the Pacific Ocean sources & trends

    SciTech Connect

    Hamilton, T.F., Millies-Lacrox, J.C.; Hong, G.H.

    1996-11-01

    The main source of artificial radioactivity in the world`s oceans can be attributed to worldwide fallout from atmospheric nuclear weapons testing. Measurements of selected artificial radionuclides in the Pacific Ocean were first conducted in the 1960`s where it was observed that fallout radioactivity had penetrated the deep ocean. Extensive studies carried out during the 1973-74 GEOSECS provided the first comprehensive data on the lateral and vertical distributions of {sup 9O}Sr, {sup 137}Cs and Pu isotopes in the Pacific on a basin wide scale. Estimates of radionuclide inventories in excess of amounts predicted to be delivered by global fallout alone were attributed to close-in fallout and tropospheric inputs from early U.S. tests conducted on Bikini and Enewetak Atolls in the Equatorial Pacific. In general, levels of fallout radionuclides (including {sup 9O}Sr, {sup 137}Cs and Pu isotopes) in the surface waters of the Pacific Ocean have decreased considerably over the past 4 decades and are now much more homogeneously distributed. Resuspension and the subsequent deposition of fallout radionuclides from previously deposited debris on land has become an important source term for the surface ocean. This can be clearly seen in measurements of fallout radionuclides in mineral aerosols over the Korean Peninsula (Yellow dust events). Radionuclides may also be transported from land to sea in river runoff-these transport mechanisms are more important in the Pacific Ocean where large quantities of river water and suspended sands/fluvial sediments reach the coastal zone. Another unique source of artificial radionuclides in the Pacific Ocean is derived from the slow resolubilization and transport of radionuclides deposited in contaminated lagoon and slope sediments near U.S. and French test sites. Although there is a small but significant flux of artificial radionuclides depositing on the sea floor, > 80% of the total 239, {sup 240}Pu inventory and > 95% of the total {sup

  15. Using 137 Cs measurements to investigate the influence of erosion and soil redistribution on soil properties.

    PubMed

    Du, P; Walling, D E

    2011-05-01

    Information on the interaction between soil erosion and soil properties is an important requirement for sustainable management of the soil resource. The relationship between soil properties and the soil redistribution rate, reflecting both erosion and deposition, is an important indicator of this interaction. This relationship is difficult to investigate using traditional approaches to documenting soil redistribution rates involving erosion plots and predictive models. However, the use of the fallout radionuclide (137)Cs to document medium-term soil redistribution rates offers a means of overcoming many of the limitations associated with traditional approaches. The study reported sought to demonstrate the potential for using (137)Cs measurements to assess the influence of soil erosion and redistribution on soil properties (particle size composition, total C, macronutrients N, P, K and Mg, micronutrients Mn, Mo, Fe, Cu and Zn and other elements, including Ti and As). (137)Cs measurements undertaken on 52 soil cores collected within a 7 ha cultivated field located near Colebrooke in Devon, UK were used to establish the magnitude and spatial pattern of medium-term soil redistribution rates within the field. The soil redistribution rates documented for the individual sampling points within the field ranged from an erosion rate of -12.9 t ha(-1) yr(-1) to a deposition rate of 19.2 t ha(-1) yr(-1). Composite samples of surface soil (0-5 cm) were collected immediately adjacent to each coring point and these samples were analysed for a range of soil properties. Individual soil properties associated with these samples showed significant variability, with CV values generally lying in the range 10-30%. The relationships between the surface soil properties and the soil redistribution rate were analysed. This analysis demonstrated statistically significant relationships between some soil properties (total phosphorus, % clay, Ti and As) and the soil redistribution rate, but for

  16. (137)Cs inter-plant concentration ratios provide a predictive tool for coral atolls with distinct benefits over transfer factors.

    PubMed

    Robison, William L; Hamilton, Terry F; Bogen, Kenneth T; Conrado, Cynthia L; Kehl, Steven R

    2008-01-01

    Inter-plant concentration ratios (IPCR) [Bqg(-1)(137)Cs in coral atoll tree food crops/Bqg(-1)(137)Cs in leaves of native plant species whose roots share a common soil volume] can replace transfer factors (TF) to predict (137)Cs concentration in tree food crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact that tree roots naturally integrate (137)Cs over large volumes of soil. Root absorption of (137)Cs replaces large-scale, expensive soil sampling schemes to reduce variability in (137)Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log-normally distributed (LND) with geometric standard deviation (GSD)=1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSDs of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD=1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10-20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples. PMID:17904254

  17. 137Cs Inter-Plant Concentration Ratios Provide a Predictive Tool for Coral Atolls with Distinct Benefits Over Transfer Factors

    SciTech Connect

    Robison, W L; Hamilton, T F; Bogen, K; Corado, C L; Kehl, S R

    2007-07-17

    Inter-plant concentration ratios (IPCR), [Bq g{sup -1} {sup 137}Cs in coral atoll tree food-crops/Bq g{sup -1} {sup 137}Cs in leaves of native plant species whose roots share a common soil volume], can replace transfer factors (TF) to predict {sup 137}Cs concentration in tree food-crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact tree roots naturally integrate 137Cs over large volumes of soil. Root absorption of {sup 137}Cs replaces large-scale, expensive soil sampling schemes to reduce variability in {sup 137}Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log normally distributed (LND) with geometric standard deviation (GSD) = 1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSD's of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD = 1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10 to 20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples.

  18. (137)Cs inter-plant concentration ratios provide a predictive tool for coral atolls with distinct benefits over transfer factors.

    PubMed

    Robison, William L; Hamilton, Terry F; Bogen, Kenneth T; Conrado, Cynthia L; Kehl, Steven R

    2008-01-01

    Inter-plant concentration ratios (IPCR) [Bqg(-1)(137)Cs in coral atoll tree food crops/Bqg(-1)(137)Cs in leaves of native plant species whose roots share a common soil volume] can replace transfer factors (TF) to predict (137)Cs concentration in tree food crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact that tree roots naturally integrate (137)Cs over large volumes of soil. Root absorption of (137)Cs replaces large-scale, expensive soil sampling schemes to reduce variability in (137)Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log-normally distributed (LND) with geometric standard deviation (GSD)=1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSDs of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD=1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10-20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples.

  19. Influence of biologically-active substances on {sup 137}Cs and heavy metals uptake by Barley plant

    SciTech Connect

    Kruglov, Stanislav; Filipas, Alexander

    2007-07-01

    Available in abstract form only. Full text of publication follows: When solving the problem of contaminated agricultural lands rehabilitation, most of attention is concentrated on the effective means which allow the obtaining of ecologically safe production. The minimization of radionuclides and heavy metals (HM) content in farm products on the basis of their migration characteristics in agro-landscapes and with the regard for different factors influencing contaminants behavior in the soil-plant system is of great significance. Our investigation has shown that the effect of biologically active substances (BAS) using for seeds treatment on {sup 137}Cs transfer to barley grown on Cd contaminated soil was dependent on their properties and dosage, characteristics of soil contamination and biological peculiarities of plants, including stage of plants development. Seeds treatment by plant growth regulator Zircon resulted in a significant increase in {sup 137}Cs activity in harvest (40- 50%), increase in K concentration and significant reduction in Ca concentration. Increased Cd content in soil reduced {sup 137}Cs transfer to barley plants by 30-60% (p<0,05) and Zircon application further reduced its concentration. Ambiol and El also reduced {sup 137}Cs uptake by roots and Cd and Pb phyto-toxicity. The experimental data do not make it possible to link the BAS effect on inhibition of {sup 137}Cs absorption by plants directly with their influence on HM phyto-toxicity. The dependence of Concentration Ratio of {sup 137}Cs on the Ambiol and El dose was not proportional and the most significant decrease in the radionuclide uptake by plants was reported with the use of dose showing the most pronounced stimulating effect on the barley growth and development. The pre-sowing seed treatment with Ambiol increased Pb absorption by 35-50% and, on the contrary, decreased Cd uptake by plants by 30-40%. (authors)

  20. Long-term behavior of (90)Sr and (137)Cs in the environment: Case studies in Switzerland.

    PubMed

    Corcho-Alvarado, J A; Balsiger, B; Sahli, H; Astner, M; Byrde, F; Röllin, S; Holzer, R; Mosimann, N; Wüthrich, S; Jakob, A; Burger, M

    2016-08-01

    We present long-term records of the (137)Cs and (90)Sr activity concentrations in soil, grass and milk from two lowland and two alpine pastures of Switzerland. The data is used for better understanding the long-term behavior of these radionuclides in the environment. Transfer factors between compartments are used as qualitative indicators of the magnitude of transfer and as a way to compare different elements (e.g. Cs and Sr) in similar conditions. The long-term behavior was quantified by means of the effective half-life which integrates all processes that cause a decrease of activity in a given medium such as leaching, fixation, erosion and radioactive decay. Our study shows that (90)Sr is more likely transferred from alpine soil to grass than (137)Cs. This is explained by a stronger fixation of Cs in the soils. We observed higher transfers of (90)Sr to grass in soils with lower Ca concentrations, and vice versa. In contrast, the transfer of (137)Cs to grass was not affected by the variations of the K content in the soil. We provide evidence that shows that (137)Cs, after intake by dairy cattle, is more likely transferred to milk than (90)Sr. However, as the (90)Sr and Ca transfers to milk are influenced by parameters/processes that were not taken into account in our study, our result cannot be entirely validated. The effective half-lives of (137)Cs and (90)Sr in soil, grass and milk corresponded with previous estimates in alpine soils. We have found that processes other than radioactive decay are responsible for a major decrease of the (90)Sr activity in soil. For (137)Cs, on the other hand, radioactive decay is among the most relevant process. Our data shows to be of interest in studying the trends of behavior of radionuclides in alpine regions. PMID:27132253

  1. Growth rate of a deep-sea coral using sup 210 Pb and other isotopes

    SciTech Connect

    Druffel, E.R.M.; King, L.I.; Belastock, R.A.; Buesseler, K.O. )

    1990-05-01

    A deep-sea coral was studied to determine its growth rate and to reconstruct time histories of isotope distributions in the deep ocean. The specimen was collected at a depth of 600 m off Little Bahama Banks using the Deep Submergence Vehicle (DSV) Alvin. The growth rate of the calcitic coral trunk was determined using excess {sup 210}Pb measured in concentric bands. Excess {sup 210}Pb was found in the outer half of the coral's radius, and a growth rate of 0.11 {plus minus} 0.02 mm/a is calculated. Assuming a constant growth rate during formation of the entire trunk, an age of 180 {plus minus} 40 a is estimated for the coral. The decrease observed in radiocarbon activities measured on the same bands (Griffin and Druffel, 1989) concurred with the growth rate estimated from excess {sup 210}Pb activity. {sup 239,240}Pu activities measured by mass spectrometry were also detected in the outer two bands of the coral, as expected from the {sup 210}Pb chronology. Stable oxygen and carbon isotopes measured in samples collected by a variety of techniques are positively correlated. This is evidence of a variable kinetic isotope effect most likely caused by variations in the skeletal growth rate. Long-lived corals such as this specimen have the potential for serving as integrators of seawater chemistry in the deep-sea over several century timescales.

  2. /sup 210/Pb dating and the recent geologic history of Crystal Bay, Lake Minnetonka, Minnesota

    SciTech Connect

    Murchie, S.L.

    1985-11-01

    /sup 210/Pb dating of five cores from Crystal Bay, Lake Minnetonka, was used to examine the geologic history of the basin during the last century. A lakewide /sup 210/Pb budget and the basinwide average cumulative activities of /sup 210/Pb within time-stratigraphic units were estimated from multiple cores. Ages of time-stratigraphic markers and sediment accumulation rates of time-stratigraphic units were calculated from a constant-flux /sup 210/Pb-dating model. The basinwide bulk-sediment accumulation rate was found to have increased from 0.003 g cm/sup -2/ yr/sup -1/ before settlement to 0.07 g cm/sup -2/ yr/sup -1/ for the period from 1962 to 1983. Since settlement of the surrounding area, profundal sediment became highly calcareous and accumulation of littoral marl began. Intensity of focusing of sediment to the center of Crystal Bay decreased as basinwide sediment accumulation rates increased. Light organic sediment was also found to be more intensely focused than heavier siliceous or calcareous sediment. Accumulation of sediment spread to regions shallower than 5 m as the rate of sedimentation exceeded the rate of sediment resuspension at the depth, about 4 mm yr/sup -1/.

  3. Lead precipitation fluxes at tropical oceanic sites determined from /sup 210/Pb measurements

    SciTech Connect

    Settle, D.M.; Patterson, C.C.; Turekian, K.K.; Cochran, J.K.

    1982-02-20

    Concentrations of lead, /sup 210/Pb, and /sup 210/Po were measured in rain selected for least influence by local sources of contamination at several tropical and subtropical islands (Enewetak; Pigeon Key, Florida; and American Samoa) and shipboard stations (near Bermuda and Tahiti). Ratios expressed as ng Pb/dpm /sup 210/Pb in rain were 250--900 for Pigeon Key (assuming 12% adsorption for /sup 210/Pb and no adsorption for lead), depending on whether the air masses containing the analyzed rain came from the Caribbean or from the continent, respectively; about 390 for the northern Sargasso Sea downwind from emissions of industrial lead in North America; 65 for Enewetak, remote from continental emissions of industrial lead in the northern hemisphere; and 14 near Tahiti, a remote location in the southern hemisphere where industrial lead emissions to the atmosphere are much less than in the northern hemisphere. (The American Samoa sample yielded a higher ratio than Tahiti; the reason for this is not clear but may be due to local Pb sources). The corresponding fluxes of lead to the oceans, based on measured or modeled /sup 210/Pb precipitation fluxes, are about 4 ng Pb/cm/sup 2/y for Tahiti, 10 for Enewetak, and 270 for the Sargasso Sea site, and between 110 to 390 at Pigeon Key.

  4. Epiphytic fruticose lichens as biomonitors for retrospective evaluation of the (134)Cs/(137)Cs ratio in Fukushima fallout.

    PubMed

    Ramzaev, V; Barkovsky, A; Gromov, A; Ivanov, S; Kaduka, M

    2014-12-01

    In 2011-2013, sampling of epiphytic fruticose lichens of the genera Usnea, Bryoria and Alectoria was carried out on Sakhalin and Kuril Islands (the Sakhalin region, Russia) to investigate contamination of these organisms with the Fukushima-derived (134)Cs and (137)Cs. Activities of the radionuclides were determined in all 56 samples of lichens taken for the analysis. After correction for radioactive decay (on 15 March 2011), the activity concentrations ranged from 2.1 Bq kg(-1) (d.w.) to 52 Bq kg(-1) for (134)Cs and from 2.3 Bq kg(-1) to 52 Bq kg(-1) for (137)Cs. Cesium-134 and (137)Cs activities for the whole set of lichens (n = 56) were strongly positively correlated; Spearman's rank correlation coefficient was calculated as 0.991 (P < 0.01). The activity concentrations of (134)Cs and (137)Cs in Usnea lichens from the Sakhalin and Kunashir islands declined with a factor of three in the period from 2011 to 2013. The average biological half-time for both cesium radionuclides in lichens of the genus Usnea is estimated as 1.3 y. The mean of 0.99 ± 0.10 and median of 0.99 were calculated for the decay corrected (134)Cs/(137)Cs activities ratios in the lichens (n = 56). The radionuclides ratio in the lichens did not depend on location of sampling site, species and the time that had passed after the Fukushima accident. The regression analysis has shown the background pre-Fukushima level of (137)Cs of 0.4 ± 0.3 Bq kg(-1), whereas the ratio between the Fukushima-borne (134)Cs and (137)Cs in the lichens was estimated as 1.04. The (134)Cs/(137)Cs activities ratio in lichens from the Sakhalin region is consistent with the ratios reported by others for the heavy contaminated areas on Honshu Island in Japan following the Fukushima accident. The activity concentrations of natural (7)Be in lichens from the Sakhalin region varied between 100 Bq kg(-1) and 600 Bq kg(-1); the activity concentrations did not exhibit temporal variations during a 2y

  5. (7)Be, (210)Pb, and (210)Po in the surface air from the Arctic to Antarctica.

    PubMed

    Persson, Bertil R R; Holm, Elis

    2014-12-01

    In the present study we have investigated the activity concentrations of (210)Pb, (210)Po as well as (7)Be in surface air of the North and South Atlantic (1988-1989), the Arctic Ocean (1991), and along the coastline of Siberia (1994) during succeeding expeditions in the Swedish Polar Research program. During the cruises in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average air concentrations of (7)Be was 0.6 ± 0.4 mBq/m(3), (210)Pb 40 ± 4 μBq/m(3) and (210)Po-38 ± 10 μBq/m(3). During the Swedish-Russian Tundra Ecology-94 expedition along the Siberian coastline the average air concentrations of (7)Be and (210)Pb measured during May-July were 11 ± 3, and 2.4 ± 0.4 mBq/m(3), and during July-September they were 7.2 ± 2 and 2.7 ± 1.1 mBq/m(3) respectively. The results from measurements of the activity concentration of (210)Pb in the air over the Arctic Ocean vary between 75 and 176 μBq/m(3). In the air close to land masses, however, the activity concentration of (210)Pb in the air increases to 269-2712 μBq/m(3). The activity concentration of (7)Be in the South Atlantic during the cruise down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m(3). The activity concentration of (210)Pb in the South Atlantic down to Antarctica varied between 6 and 14 μBq/m(3). At the Equator the activity concentration recorded in November 1988 was 630 μBq/m(3) and in April 1989 it was 260 μBq/m(3). The average activity concentration of (210)Pb during the route Gothenburg-Montevideo in 1988 was 290 and on the return Montevideo-Gothenburg it was 230 μBq/m(3). The activity concentration of (210)Po in the South Atlantic down to Antarctica varied between 15 and 58 μBq/m(3). At the Equator the activity concentration in November 1988 was 170 and in April 1989 it was 70 μBq/m(3). The average activity concentration of (210)Po during the route Gothenburg-Montevideo in 1988 was 63 and on the return Montevideo

  6. (7)Be, (210)Pb, and (210)Po in the surface air from the Arctic to Antarctica.

    PubMed

    Persson, Bertil R R; Holm, Elis

    2014-12-01

    In the present study we have investigated the activity concentrations of (210)Pb, (210)Po as well as (7)Be in surface air of the North and South Atlantic (1988-1989), the Arctic Ocean (1991), and along the coastline of Siberia (1994) during succeeding expeditions in the Swedish Polar Research program. During the cruises in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average air concentrations of (7)Be was 0.6 ± 0.4 mBq/m(3), (210)Pb 40 ± 4 μBq/m(3) and (210)Po-38 ± 10 μBq/m(3). During the Swedish-Russian Tundra Ecology-94 expedition along the Siberian coastline the average air concentrations of (7)Be and (210)Pb measured during May-July were 11 ± 3, and 2.4 ± 0.4 mBq/m(3), and during July-September they were 7.2 ± 2 and 2.7 ± 1.1 mBq/m(3) respectively. The results from measurements of the activity concentration of (210)Pb in the air over the Arctic Ocean vary between 75 and 176 μBq/m(3). In the air close to land masses, however, the activity concentration of (210)Pb in the air increases to 269-2712 μBq/m(3). The activity concentration of (7)Be in the South Atlantic during the cruise down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m(3). The activity concentration of (210)Pb in the South Atlantic down to Antarctica varied between 6 and 14 μBq/m(3). At the Equator the activity concentration recorded in November 1988 was 630 μBq/m(3) and in April 1989 it was 260 μBq/m(3). The average activity concentration of (210)Pb during the route Gothenburg-Montevideo in 1988 was 290 and on the return Montevideo-Gothenburg it was 230 μBq/m(3). The activity concentration of (210)Po in the South Atlantic down to Antarctica varied between 15 and 58 μBq/m(3). At the Equator the activity concentration in November 1988 was 170 and in April 1989 it was 70 μBq/m(3). The average activity concentration of (210)Po during the route Gothenburg-Montevideo in 1988 was 63 and on the return Montevideo

  7. Localized lesions induced by sup 137 Cs during the Goiania accident

    SciTech Connect

    Oliveira, A.R.; Brandao-Mello, C.E.; Valverde, N.J.; Farina, R.; Curado, M.P. )

    1991-01-01

    A description is given of initial symptoms and clinical observations regarding acute localized radiation lesions in 28 persons exposed to 137Cs during the Goiania radiological accident. Specialized procedures to estimate the extent and gravity of the lesions and establish a therapeutic strategy, as well as to anticipate the prognosis in each case, are briefly discussed. Measures taken for reduction of pain and inflammation are noted, and an explanation is given for difficulties encountered due to adverse working conditions and the serious clinical manifestations presented by various patients concomitantly with their lesions. Also noted is the difficulty in obtaining credible information regarding exposure, such as source-to-object distance, duration of exposure, and source activity, which precluded dosimetry studies in most cases.

  8. [Radionuclides 90Sr and 137Cs in the benthos near the nuclear submarine "Komsomolets"].

    PubMed

    Kuznetsov, A P; Shmelev, I P; Demidov, A M; Efimov, B V; Shubko, V M

    1999-01-01

    We have analyzed the content of radionuclides 90Sr and 137Cs in the benthofauna and deposits near the nuclear submarine "Komsomolets." Analysis was performed on the basis of the materials of the 31st (1993) and 36th (1995) voyages of R/V "Akademik Mstislav Keldysh" in correspondence with the system of monitoring the state of the abiotic and biotic situation near the nuclear submarine "Komsomolets" (Norwegian Sea). Whereas during the 33rd voyage of this vessel (1994) the content of these elements in the benthic animals at stations located close to the submarine somewhat exceeded the background level of radioactivity (Kuznetsov et al., 1996), no such excess was found during the 31st and 36th voyages. Meanwhile, radioactive cobalt (60Co) was found in representatives of three groups of animals during the 31st voyage at two stations located near the submarine. PMID:10188365

  9. Influence of soil acidification in southern Norway on the 137Cs exposure of moose?

    PubMed

    Steinnes, Eiliv; Gaare, Eldar; Engen, Steinar

    2009-06-01

    The mean (137)Cs activity concentration in 278 liver samples of moose (Alces alces) from 16 municipalities located in different parts of Norway varied within the range 43-752 Bq kg(-1) among the municipalities. In general the geographical variation corresponded to the fallout pattern produced by the Chernobyl accident. In three communities in the southernmost part of the country however the transfer factor, defined as the activity in moose liver divided by the corresponding level in surface soil, was 6.5 times higher on average than elsewhere in Norway. Possible reasons for this highly significant difference are discussed, and it is hypothesized that the apparently much higher plant uptake in the south may be related to extensive soil acidification in this area from transboundary pollution.

  10. Vertical migration studies of 137Cs from nuclear weapons fallout and the Chernobyl accident.

    PubMed

    Almgren, S; Isaksson, M

    2006-01-01

    The vertical migration of (137)Cs originating from nuclear weapons fallout (NWF) and the Chernobyl accident has been studied at 33 sampling sites in western Sweden. An attempt to describe the present depth distribution with a solution to the convection-diffusion equation (CDE) with a pulse-like fallout event as the initial condition was made. A sum of two CDEs describing the NWF and Chernobyl debris was fitted to the actual depth profiles measured by soil sampling. The fitted depth profiles were used to correct in situ measurements for the actual depth distribution, showing good agreement with the accumulated activities in soil samples. As expected, the vertical migration was very slow and most caesium was still present in the upper soil layers. The ranges of the apparent convection velocity, v, and apparent diffusion coefficient, D, were between 0 and 0.35 cm/year and 0.06 and 2.63 cm(2)/year, respectively.

  11. An empirical multivariate log-normal distribution representing uncertainty of biokinetic parameters for 137Cs.

    PubMed

    Miller, G; Melo, D; Martz, H; Bertelli, L

    2008-01-01

    A simplified biokinetic model for (137)Cs has six parameters representing transfer of material to and from various compartments. Using a Bayesian analysis, the joint probability distribution of these six parameters is determined empirically for two cases with quite a lot of bioassay data. The distribution is found to be a multivariate log-normal. Correlations between different parameters are obtained. The method utilises a fairly large number of pre-determined forward biokinetic calculations, whose results are stored in interpolation tables. Four different methods to sample the multidimensional parameter space with a limited number of samples are investigated: random, stratified, Latin Hypercube sampling with a uniform distribution of parameters and importance sampling using a lognormal distribution that approximates the posterior distribution. The importance sampling method gives much smaller sampling uncertainty. No sampling method-dependent differences are perceptible for the uniform distribution methods. PMID:18420573

  12. The influence of forest shelterbelts on 137Cs fallout in Chernobyl affected areas (Tula region, Russia).

    NASA Astrophysics Data System (ADS)

    Ivanov, Maxim; Shamshurina, Eugeniya; Tatyana, Paramonova; Vladimir, Belyaev; Angelina, Gavruchenkova; Nikolai, Lugovoy; Konstantinov, Pavel

    2015-04-01

    The radioactive fallout after Chernobyl accident caused serious contamination by 137Cs along extensive area of East-European plain.Cs137 fall down on earth surface in two ways: gravitational - "dry" and rainfall - "wet" way. "Dry" fallout is a result of direct deposition of radionuclides from atmosphere with average speed of about 0.1-1 mm/sec. The fate of "dry fall"is far less than rainfall mechanism. Erupted water steam of reactor zone full of radioactive material enriched precipitation with 137Cs. Therefore, the derived spatial structure of contamination was under control of rainfall pattern in May-June 1986. On the areas affected by rainfall fallout was the Southern part of Tula region in Middle Russia. It got name as "Plava hot spot" by the town in the center of this area. Tula is a traditional rural region, the vast areas covered by chernozem soils are cultivated for centuries. During cultivation forest cover was reduced that urged growth of wind erosion and loss of soil fertility. Hence, in the middle of 20 the century large arrangements for creation of forest shelterbelts were conducted. High efficiency of shelterbelts made them a widely provided part of new human-transformed landscape. Usually shelterbelts are set as a regular network across main direction of winds in particular region. Such organization help to reduce speed of air steam in the lowest 20-30 m layer of atmosphere. In addition, shelterbelts are very good collectors of snow in winter time which increase total moisture of soil and its fertility. Represented investigation is conducted to find out any correlation between shelterbelts and fallout of radionuclides. If such correlation is significant, it has to be taken into account for further environmental surveys. Two shelterbelts on the interfluve positions were chosen for detailed examination. Both selected objects emerged before 1986 but have different width, floristic composition, orientation and type of construction. One of shelterbelts is

  13. EVALUATION OF THE MIGRATION POTENTIAL FOR 60Co AND 137Cs AT THE MAINE YANKEE SITE.

    SciTech Connect

    FUHRMANN,M.SULLIVAN,T.

    2002-08-08

    The objective of this report is to discuss the degree of sorption and desorption of {sup 137}Cs and {sup 60}Co that may be associated with the granite bedrock and the ''popcorn'' cement drain system that underlie the Maine Yankee Containment Foundation. The purpose is to estimate how much retardation of these two radionuclides takes place in groundwater that flows in the near-field of the Containment Foundation, specifically with respect to contamination originating at the PAB Test Pit. Specific concerns revolve around the potential for the contamination originating near the PAB to create a radioactive dose to a hypothetical ''resident farmer'' using a well intercepting this water to exceed 4 millirems/yr.

  14. Tracing soil erosion impacts on soil organisms using 137Cs and soil nematodes

    NASA Astrophysics Data System (ADS)

    Baxter, Craig; Rowan, John S.; McKenzie, Blair M.; Neilson, Roy

    2014-05-01

    The application of environmental radionuclides in soil tracing and erosion studies is now well established in geomorphology. Sediment and erosion-tracing studies are undertaken for a range of purposes in the earth sciences but until now few studies have used the technique to answer biological questions. An experiment was undertaken to measure patterns of soil loss and gain over 50 years, effectively calculating a field-scale sediment budget, to investigate soil erosion relationships between physical and biological soil components. Soil nematodes were identified as a model organism, a ubiquitous and abundant group sensitive to disturbance and thus useful indicator taxa of biological and physico-chemical changes. A field site was selected at the James Hutton Institute's experimental Balruddery Farm in NE Scotland. 10 metre-resolution topographical data was collected with differential GPS. Based on these data, a regular 30 m-resolution sampling grid was constructed in ArcGIS, and a field-sampling campaign undertaken. 104 soil cores (~50 cm-deep) were collected with a percussion corer. Radio-caesium (137Cs) activity concentrations were measured using high-purity germainum gamma-ray spectroscopy, and 137Cs areal activities derived from these values. Organic matter content by loss on ignition and grain-size distribution by laser granulometry were also measured. Additional samples were collected to characterise the soil nematode community, both for abundance and functional (trophic) composition using a combination of low-powered microscopy and molecular identification techniques (dTRFLP). Results were analysed with ArcGIS software using the Spatial Analyst package. Results show that spatial relationships between physical, chemical and biological parameters were complex and interrelated. Previous field management was found to influence these relationships. The results of this experiment highlight the role that soil erosion processes play in medium-term restructuring of the

  15. Relationships of 137Cs inventory with magnetic measures of calcareous soils of hilly region in Iran.

    PubMed

    Ayoubi, Shamsollah; Ahmadi, Mohamamd; Abdi, Mohammad Reza; Abbaszadeh Afshar, Farideh

    2012-10-01

    Erosion is a natural process, but it has been dramatically increased by human activities; and this adversely influences soil productivity and environmental quality. For quantification of soil erosion, several techniques including the use of Cs-137 have been employed. This study was conducted to explore the relationships of Cs-137 inventory with magnetic properties in calcareous soils in western Iran. Ten transects were selected in the hilly region in Chelgerd district of Iran. Soil samples from 0 to 30 and 30-50 cm depths were collected from fifty points to determine Cs-137 inventory, magnetic measures and selected physico-chemical properties (in total there were 100 soil samples). The results showed that simple mass balance model (SMBM) estimated a gross erosion rate of 29.6 t ha(-1) yr(-1) and a net soil deposition of 21.8 t ha(-1) yr(-1); hence, a net soil loss of 9.6 t ha(-1) yr(-1) and a sediment delivery ratio of 31.4%. Simple linear regression and non-linear regression analysis showed that mass magnetic susceptibility (χ(lf)) explained only 33.64% and 45% of variability in Cs-137 in the transects studied. The results of multiple linear regression analysis of (137)Cs with magnetic parameters and physico-chemical properties indicated that extractable potassium and χ(lf) explained approximately 61% of the total variability in (137)Cs in the area studied. Overall, the results suggest that further research is needed for the use of magnetic characteristics as an alternative technique in place Cs-137 methodology for calcareous soils. PMID:22522385

  16. Estimation Of 137Cs Using Atmospheric Dispersion Models After A Nuclear Reactor Accident

    NASA Astrophysics Data System (ADS)

    Simsek, V.; Kindap, T.; Unal, A.; Pozzoli, L.; Karaca, M.

    2012-04-01

    Nuclear energy will continue to have an important role in the production of electricity in the world as the need of energy grows up. But the safety of power plants will always be a question mark for people because of the accidents happened in the past. Chernobyl nuclear reactor accident which happened in 26 April 1986 was the biggest nuclear accident ever. Because of explosion and fire large quantities of radioactive material was released to the atmosphere. The release of the radioactive particles because of accident affected not only its region but the entire Northern hemisphere. But much of the radioactive material was spread over west USSR and Europe. There are many studies about distribution of radioactive particles and the deposition of radionuclides all over Europe. But this was not true for Turkey especially for the deposition of radionuclides released after Chernobyl nuclear reactor accident and the radiation doses received by people. The aim of this study is to determine the radiation doses received by people living in Turkish territory after Chernobyl nuclear reactor accident and use this method in case of an emergency. For this purpose The Weather Research and Forecasting (WRF) Model was used to simulate meteorological conditions after the accident. The results of WRF which were for the 12 days after accident were used as input data for the HYSPLIT model. NOAA-ARL's (National Oceanic and Atmospheric Administration Air Resources Laboratory) dispersion model HYSPLIT was used to simulate the 137Cs distrubition. The deposition values of 137Cs in our domain after Chernobyl Nuclear Reactor Accident were between 1.2E-37 Bq/m2 and 3.5E+08 Bq/m2. The results showed that Turkey was affected because of the accident especially the Black Sea Region. And the doses were calculated by using GENII-LIN which is multipurpose health physics code.

  17. Damage of the mouse testis by tritiated water and 137Cs-gamma-rays.

    PubMed

    Kashiwabara, Shoji; Kashimoto, Naoki; Sanoh, Seigo; Uesaka, Toshihiro; Katoh, Osamu; Watanabe, Hiromitsu

    2003-09-01

    Tritiated water at 23.2, 46.3 or 92.5 MBq/animal and 137Cs-gamma-rays at 9.5 Gy (equivalent 370 MBq) or lower doses were administered to 6-week old male C3H/HeNCrj and C57BL/6NCrj mice, as well as F1 Crj: B6C3F1 (C3H x C57BL) progeny. Each set of six to ten animals were autopsied 30 days after the first irradiation. Testis weights were decreased dose dependently, relative values being highest in the C3H and lowest in the C57BL case, with B6C3F1 intermediate. Vacuolization in seminiferous tubules appeared in the 23.2 MBq group and increased with the dose. Focal pyknosis and karyomegaly were found at 46.3 MBq, while primary and secondary spermatocytes and spermatids disappeared with 92.5 MBq. Only a few spermatogonia and Sertoli cells remained after exposure to 9.5 Gy 137Cs-gamma-rays. Sizes of seminiferous tubules were decreased dose dependently, with no strain differences. When male B6C3F1 mice were irradiated with Cs-gamma-rays at 0.119 (equivalent 4.63 MBq tritiated water) or 2.38 Gy (equivalent 92.5 MBq tritiated water), body weights and size of the seminiferous tubules were decreased at both doses, and the larger dose also caused reduction of testis weight and abnormal sperm. However, all changes except for the alteration in weights had disappeared 1 month after the final irradiation. It is considered that the size of seminiferous tubules may be a good parameter for radiation damage in the testis.

  18. Effect of periodic wetting and drying on selective sorption of 137Cs by mixtures of soil and organomineral sorbent

    NASA Astrophysics Data System (ADS)

    Popov, V. E.; Maslova, K. M.; Stepina, I. A.

    2014-05-01

    The incubation of sandy soddy-podzolic soil with a three-component organomineral sorbent (OMS) on the basis of sapropel, neutralized hydrolysis lignin, and clay-salt slime under alternating wetting-drying (W-D) conditions for two years has increased the selective sorption of 137Cs by 2.5-5 times. The addition of 5% OMS increases the effect of periodic W-D cycles on the selective sorption of 137Cs compared to the addition of 10% OMS. The relationship between the 137Cs interception potential and the number of W-D cycles has been predicted on the basis of the additivity rule and under the assumption that this potential linearly depends on the number of W-D cycles. The predicted values of the 137Cs interception potential almost coincide with the experimental data for the mixtures of sandy soddy-podzolic soil with 10% OMS and are lower than the experimental values by 60% for the mixtures of soil with 10% OMS.

  19. Modelling temporal trends of 137Cs and 99Tc concentrations in Fucus vesiculosus from the eastern Irish coastline.

    PubMed

    Cournane, S; Vintró, L León; Mitchell, P I; McMahon, C A; Smith, K; Long, S

    2011-11-01

    Time series of 137Cs and 99Tc activity concentrations in the brown seaweed Fucus vesiculosus and seawater, gathered at three locations on the eastern Irish coastline during the period 1988-2008, have been modelled using a novel approach incorporating a variable uptake rate in the seaweed. Seasonal variations in the time series, identified using spectral analysis, were incorporated into the model which was used to determine transfer kinetic parameters and to predict 137Cs and 99Tc concentrations in seaweed, as influenced by levels in ambient seawater. An optimisation method combining evolutionary and grid search minimisation techniques was adopted to determine the best values for the model parameters, from which concentration factors (CF) and biological half-lives (tb1/2) for 137Cs and 99Tc in F. vesiculosus were calculated. CF values of 170-179 and 1.1×105 l kg(-1) (dry weight) were obtained for 137Cs and 99Tc, respectively, while the corresponding tb1/2 values were 39-47 and 32 days, respectively.

  20. A comparison of 90Sr and 137Cs uptake in plants via three pathways at two Chernobyl-contaminated sites.

    PubMed

    Malek, M A; Hinton, T G; Webb, S B

    2002-01-01

    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. Root uptake was 200 times greater than foliar absorption at the near-field site of Chistogalovka and eight times greater at Polesskoye, where the fallout consisted of the more soluble condensation-type, rather than fuel particles. Strontium's bioavailability exceeded that of 137Cs (analyzed in the same plants) by orders of magnitude when compared using concentration ratios. Simplistic, cumulative effective dose calculations for humans ingesting 90Sr- and 137Cs-contaminated plants revealed that the dose at Chistogalovka was greater from 90Sr (185 mSv vs. 3 mSv from 137Cs), while at Polesskoye the dose from 137Cs (66 mSv) was 30 times greater than from 90Sr (2 mSv). PMID:11814162

  1. Modeling of 137Cs migration in soils using an 80-year soil archive: role of fertilizers and agricultural amendments.

    PubMed

    Monna, F; van Oort, F; Hubert, P; Dominik, J; Bolte, J; Loizeau, J-L; Labanowski, J; Lamri, J; Petit, C; Le Roux, G; Chateau, C

    2009-01-01

    An 80-year soil archive, the 42-plot experimental design at the INRA in Versailles (France), is used here to study long-term contamination by 137Cs atmospheric deposition and the fate of this radioisotope when associated with various agricultural practices: fallow land, KCl, NH4(NO3), superphosphate fertilizers, horse manure and lime amendments. The pertinence of a simple box model, where radiocaesium is supposed to move downward by convectional mechanisms, is checked using samples from control plots which had been neither amended, nor cultivated since 1928. This simple model presents the advantage of depending on only two parameters: alpha, a proportional factor allowing the historical atmospheric 137Cs fluxes to be reconstructed locally, and k, an annual loss coefficient from the plow horizon. Another pseudo-unknown is however necessary to run the model: the shape of historical 137Cs deposition, but this function can be easily computed by merging several curves previously established by other surveys. A loss of approximately 1.5% per year from the plow horizon, combined with appropriate fluxes, provides good concordance between simulated and measured values. In the 0-25cm horizon, the residence half time is found to be approximately 18yr (including both migration and radioactive decay). Migration rate constants are also calculated for some plots receiving continuous long-term agricultural treatments. Comparison with the control plots reveals significant influence of amendments on 137Cs mobility in these soils developed from a unique genoform. PMID:19013695

  2. Modeling of 137Cs migration in soils using an 80-year soil archive: role of fertilizers and agricultural amendments.

    PubMed

    Monna, F; van Oort, F; Hubert, P; Dominik, J; Bolte, J; Loizeau, J-L; Labanowski, J; Lamri, J; Petit, C; Le Roux, G; Chateau, C

    2009-01-01

    An 80-year soil archive, the 42-plot experimental design at the INRA in Versailles (France), is used here to study long-term contamination by 137Cs atmospheric deposition and the fate of this radioisotope when associated with various agricultural practices: fallow land, KCl, NH4(NO3), superphosphate fertilizers, horse manure and lime amendments. The pertinence of a simple box model, where radiocaesium is supposed to move downward by convectional mechanisms, is checked using samples from control plots which had been neither amended, nor cultivated since 1928. This simple model presents the advantage of depending on only two parameters: alpha, a proportional factor allowing the historical atmospheric 137Cs fluxes to be reconstructed locally, and k, an annual loss coefficient from the plow horizon. Another pseudo-unknown is however necessary to run the model: the shape of historical 137Cs deposition, but this function can be easily computed by merging several curves previously established by other surveys. A loss of approximately 1.5% per year from the plow horizon, combined with appropriate fluxes, provides good concordance between simulated and measured values. In the 0-25cm horizon, the residence half time is found to be approximately 18yr (including both migration and radioactive decay). Migration rate constants are also calculated for some plots receiving continuous long-term agricultural treatments. Comparison with the control plots reveals significant influence of amendments on 137Cs mobility in these soils developed from a unique genoform.

  3. Comparison of Pu and (137)Cs as tracers of soil and sediment transport in a terrestrial environment.

    PubMed

    Everett, S E; Tims, S G; Hancock, G J; Bartley, R; Fifield, L K

    2008-02-01

    Following atmospheric nuclear weapons testing in the 1950s and 1960s significant quantities of (137)Cs and (239+240)Pu were deposited worldwide. In recent decades, (137)Cs has been commonly used as a tracer of soil erosion and sedimentation, particularly in the Northern Hemisphere where atomic deposition was three times as great as in the Southern Hemisphere. The relatively short 30-year half-life of this isotope means that its sensitivity as a tracer is rapidly decreasing. In contrast, with half-lives of 24,110 and 6561 years, the sensitivity of the two plutonium isotopes remains essentially the same as when it was deposited. Here we use the technique of Accelerator Mass Spectrometry to demonstrate the potential of anthropogenic Pu as an alternative to (137)Cs as a tracer of soil transport in Australia. We measure an average (137)Cs/(239+240)Pu activity ratio of 27.3+/-1.5 and an average (240)Pu/(239)Pu atom ratio of 0.149+/-0.003, both slightly lower than the global average.

  4. Tracing pre-eruptive magma degassing using ( 210Pb/ 226Ra) disequilibria in the volcanic deposits of the 1980-1986 eruption of Mount St. Helens

    NASA Astrophysics Data System (ADS)

    Berlo, Kim; Turner, Simon; Blundy, Jon; Black, Stuart; Hawkesworth, Chris

    2006-09-01

    Disequilibria between 210Pb and 226Ra can be used to trace magma degassing, because the intermediate nuclides, particularly 222Rn, are volatile. Products of the 1980-1986 eruptions of Mount St. Helens have been analysed for ( 210Pb/ 226Ra). Both excesses and deficits of 210Pb are encountered suggesting rapid gas transfer. The time scale of diffuse, non-eruptive gas escape prior to 1980 as documented by 210Pb deficits is on the order of a decade using the model developed by Gauthier and Condomines (Earth Planet. Sci. Lett. 172 (1999) 111-126) for a non-renewed magma chamber and efficient Rn removal. The time required to build-up 210Pb excess is much shorter (months) as can be observed from steady increases of ( 210Pb/ 226Ra) with time during 1980-1982. The formation of 210Pb excess requires both rapid gas transport through the magma and periodic blocking of gas escape routes. Superposed on this time trend is the natural variability of ( 210Pb/ 226Ra) in a single eruption caused by tapping magma from various depths. The two time scales of gas transport, to create both 210Pb deficits and 210Pb excesses, cannot be reconciled in a single event. Rather 210Pb deficits are associated with pre-eruptive diffuse degassing, while 210Pb excesses document the more vigorous degassing associated with eruption and recharge of the system.

  5. Transfer of {sup 210}Po and {sup 210}Pb through the lichen-caribou-wolf food chain of northern Canada

    SciTech Connect

    Thomas, P.A.; Sheard, J.W.; Swanson, S.

    1994-06-01

    Natural background activity and food chain transfer of the uranium decay products, {sup 210}Po and {sup 210}Pb, were examined in the lichen-caribou-wolf food chain at two locations in the Northwest Territories of Canada. {sup 210}Po and {sup 210}Pb activities in lichens differed with species and location. Both {sup 210}Po and {sup 210}Pb were markedly higher in caribou bone than in wolf bone. {sup 210}Po activities in liver, kidney, and muscle were similar in both species. Caribou fetuses had lower activities of {sup 210}Po but higher activities of {sup 210}Pb than maternal muscle and placenta, suggesting greater placental transport of {sup 210}Pb than {sup 210}Po. Concentration ratios (CR = Bq kg{sup {minus}1} in consumer/Bq kg{sup {minus}1} in its food source) and f{sub f} values (f{sub f} in d kg{sup {minus}1} = Bq kg{sup {minus}1} in muscle/Bq d{sup {minus}1} ingested) showed that wolves retain more {sup 210}Po and less {sup 210}Pb from their diet than do caribou. {sup 210}Po CRs averaged 0.38 for caribou/lichens, 0.26 for caribou/rumen contents, and 0.40 for wolves/caribou. {sup 210}Pb CRs averaged 0.36 for caribou/lichens, 0.57 for caribou/rumen contents, and 0.13 for wolves/caribou. 43 refs., 4 figs., 5 tabs.

  6. Transfer of 210Po and 210Pb through the lichen-caribou-wolf food chain of northern Canada.

    PubMed

    Thomas, P A; Sheard, J W; Swanson, S

    1994-06-01

    Natural background activity and food chain transfer of the uranium decay products, 210Po and 210Pb, were examined in the lichen-caribou-wolf food chain at two locations in the Northwest Territories of Canada. 210Po and 210Pb activities in lichens differed with species and location. Both 210Po and 210Pb were markedly higher in caribou bone than in wolf bone. 210Po activities in liver, kidney, and muscle were similar in both species. Caribou fetuses had lower activities of 210Po but higher activities of 210Pb than maternal muscle and placenta, suggesting greater placental transport of 210Pb than 210Po. Concentration ratios (CR = Bq kg-1 in consumer/Bq kg-1 in its food source) and ff values (ff in d kg-1 = Bq kg-1 in muscle/Bq d-1 ingested) showed that wolves retain more 210Po and less 210Pb from their diet than do caribou. 210Po CRs averaged 0.38 for caribou/lichens, 0.26 for caribou/rumen contents, and 0.40 for wolves/caribou. 210Pb CRs averaged 0.36 for caribou/lichens, 0.57 for caribou/rumen contents, and 0.13 for wolves/caribou.

  7. Influence of water management and fertilizer application on (137)Cs and (133)Cs uptake in paddy rice fields.

    PubMed

    Wakabayashi, Shokichi; Itoh, Sumio; Kihou, Nobuharu; Matsunami, Hisaya; Hachinohe, Mayumi; Hamamatsu, Shioka; Takahashi, Shigeru

    2016-06-01

    Cesium-137 derived from the Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident contaminated large areas of agricultural land in Eastern Japan. Previous studies before the accident have indicated that flooding enhances radiocesium uptake in rice fields. We investigated the influence of water management in combination with fertilizers on (137)Cs concentrations in rice plants at two fields in southern Ibaraki Prefecture. Stable Cs ((133)Cs) in the plants was also determined as an analogue for predicting (137)Cs behavior after long-term aging of soil (137)Cs. The experimental periods comprised 3 y starting from 2012 in one field, and 2 y from 2013 in another field. These fields were divided into three water management sections: a long-flooding section without midsummer drainage, and medial-flooding, and short-flooding sections with one- or two-week midsummer drainage and earlier end of flooding than the long-flooding section. Six or four types of fertilizer subsections (most differing only in potassium application) were nested in each water management section. Generally, the long-flooding treatment led to higher (137)Cs and (133)Cs concentrations in both straw and brown rice than medial- and short-flooding treatments, although there were some notable exceptions in the first experimental year at each site. Effects of differing potassium fertilizer treatments were cumulative; the effects on (137)Cs and (133)Cs concentrations in rice plants were not obvious in 2012 and 2013, but in 2014, these concentrations were highest where potassium fertilizer had been absent and lowest where basal dressings of K had been tripled. The relationship between (137)Cs and (133)Cs in rice plants was not correlative in the first experimental year at each site, but correlation became evident in the subsequent year(s). This study demonstrates a novel finding that omitting midsummer drainage and/or delaying drainage during the grain-filling period enhances

  8. Evolution and fluxes of 137Cs in the Black Sea/Turkish Straits System/North Aegean Sea

    NASA Astrophysics Data System (ADS)

    Delfanti, R.; Özsoy, E.; Kaberi, H.; Schirone, A.; Salvi, S.; Conte, F.; Tsabaris, C.; Papucci, C.

    2014-07-01

    The vertical profiles of 137Cs were determined in the North Aegean, Marmara and Black Seas, to assess inventories and fluxes of the radionuclide in these basins. The inventory of 137Cs in the Western Black Sea integrated from the surface down to 400 m water depth is 3.4 ± 0.1 kBq m- 2, which is surprisingly close to the amount determined in 1988, decay corrected to 2007 (2.9 ± 0.1 kBq m- 2). On the other hand, based on the comparison of profiles roughly 20 years apart, it is estimated that about 1 kBq m- 2 has been transferred from above the halocline to depths below the halocline, emphasizing the effective redistribution of tracers within the same period. We estimate that about 12 TBq y- 1 of 137Cs presently leaves the Black Sea with the upper layer flow through the Bosphorus and only 2 TBq y- 1 is returned with the lower layer inflow of Mediterranean water from the Marmara Sea. Accounting for river fluxes, estimated on the order of 2 TBq y- 1 few years after the Chernobyl accident, and possibly decreased by now, we can thus estimate a net rate of loss of about 8-10 TBq y- 1. Investigating the effective redistribution in the upper water column, the supply by the inflowing Mediterranean water alone does not explain the increase of 137Cs concentration and inventory at intermediate depths in the Western Black Sea. The most important mechanism transferring 137Cs and dissolved contaminants from the surface water to the sub-pycnocline layer appears to be the turbulent entrainment of a larger quantity of Black Sea water into the inflowing plume of Mediterranean water through mixing processes on the southwestern shelf and continental slope following its exit from the Bosphorus. This process produces an extra export of some10 TBq y- 1 of 137Cs from the surface to the sub-pycnocline depths of the Black Sea, a quantity comparable in magnitude to the total export out from the basin. It is the entrainment flux resulting from the mixing, and the further advection and

  9. Relationship between caesium (137Cs) load, cardiovascular symptoms, and source of food in 'Chernobyl' children -- preliminary observations after intake of oral apple pectin.

    PubMed

    Bandazhevskaya, G S; Nesterenko, V B; Babenko, V I; Yerkovich, T V; Bandazhevsky, Y I

    2004-12-18

    Seventeen years after the nuclear power accident at Chernobyl, most of the radio-contamination among the population of Southern Belarus is caused by incorporation of long-lived radioisotopes. The varying levels of 137Cs observed among children in this area are explained by the source of their food, especially by the consumption of contaminated milk produced privately. We stratified children from rural areas of Belarus (caesium [137Cs] contamination >5 Ci/km(2)) by their 137Cs loads into three distinct groups (group 1, <5 Bq/kg body weight [BW]; group 2, 38.4 +/- 2.4 Bq/kg BW; group 3, 122 +/- 18.5 Bq/kg BW). We determined the relationship between the 137Cs load and the children's main source of food and recorded their cardiovascular symptoms. Cardiovascular symptoms, ECG alterations, and arterial hypertension were significantly more frequent in children with high 137Cs burden than in children with very low 137Cs burden. Children with moderate and high 137Cs loads (groups 2 and 3) received apple pectin, a food additive, for 16 days. Apple pectin significantly decreased 137Cs loads in these groups (39% and 28%, respectively). ECG alterations improved, while cardiovascular symptoms and hypertension did not change in any group.

  10. [137Cs distribution and accumulation in organs and tissues of sheep in the event of chronic consumption of contaminated fodder in the area of the Chernobyl NPP accident].

    PubMed

    Kudriavtsev, V N; Vasil'ev, A V; Krasnova, E G; Fadeev, M Iu

    2006-01-01

    The regularities of 137Cs distribution and accumulation in organs and tissues of sheep on a farm located in the Chernobyl accidental zone were experimentally estimated. The distribution pattern of 137Cs concentration in organs and tissues is found to depend on the duration of the radionuclide uptake with the ration. During the first 24 h the highest 137Cs concentration is reported in the parenchymal organs; starting from day 30 muscular tissue and kidneys rank first, whereas in the other organs and tissues 137Cs concentration is 1.5-2 times lower. By 137Cs content and accumulation rate the study organs are arranged in a declining order as follows: muscles > > skin > liver > kidneys > heart > spleen. The mathematical models were devised describing the dynamics of increasing with time in 137Cs concentration in muscles, liver and skin. The methodology is suggested for the prediction of levels of 137Cs contamination of the muscular tissue of sheep. The time periods were regulated for sheep feeding with 137Cs contaminated fodder that ensure the production of mutton the radionuclide concentration in which meets the sanitary-hygienic standards.

  11. Distribution of oceanic 137Cs from the Fukushima Dai-ichi Nuclear Power Plant simulated numerically by a regional ocean model.

    PubMed

    Tsumune, Daisuke; Tsubono, Takaki; Aoyama, Michio; Hirose, Katsumi

    2012-09-01

    Radioactive materials were released to the environment from the Fukushima Dai-ichi Nuclear Power Plant as a result of the reactor accident after the Tohoku earthquake and tsunami of 11 March 2011. The measured (137)Cs concentration in a seawater sample near the Fukushima Dai-ichi Nuclear Power Plant site reached 68 kBq L(-1) (6.8 × 10(4)Bq L(-1)) on 6 April. The two major likely pathways from the accident site to the ocean existed: direct release of high radioactive liquid wastes to the ocean and the deposition of airborne radioactivity to the ocean surface. By analysis of the (131)I/(137)Cs activity ratio, we determined that direct release from the site contributed more to the measured (137)Cs concentration than atmospheric deposition did. We then used a regional ocean model to simulate the (137)Cs concentrations resulting from the direct release to the ocean off Fukushima and found that from March 26 to the end of May the total amount of (137)Cs directly released was 3.5 ± 0.7 PBq ((3.5 ± 0.7) × 10(15)Bq). The simulated temporal change in (137)Cs concentrations near the Fukushima Daini Nuclear Power Plant site agreed well with observations. Our simulation results showed that (1) the released (137)Cs advected southward along the coast during the simulation period; (2) the eastward-flowing Kuroshio and its extension transported (137)C during May 2011; and (3) (137)Cs concentrations decreased to less than 10 BqL(-1) by the end of May 2011 in the whole simulation domain as a result of oceanic advection and diffusion. We compared the total amount and concentration of (137)Cs released from the Fukushima Dai-ichi reactors to the ocean with the (137)Cs released to the ocean by global fallout. Even though the measured (137)Cs concentration from the Fukushima accident was the highest recorded, the total released amount of (137)Cs was not very large. Therefore, the effect of (137)Cs released from the Fukushima Dai-ichi reactors on concentration in the whole North

  12. Modeling of leachable 137Cs in throughfall and stemflow for Japanese forest canopies after Fukushima Daiichi Nuclear Power Plant accident.

    PubMed

    Loffredo, Nicolas; Onda, Yuichi; Kawamori, Ayumi; Kato, Hiroaki

    2014-09-15

    The Fukushima accident dispersed significant amounts of radioactive cesium (Cs) in the landscape. Our research investigated, from June 2011 to November 2013, the mobility of leachable Cs in forests canopies. In particular, (137)Cs and (134)Cs activity concentrations were measured in rainfall, throughfall, and stemflow in broad-leaf and cedar forests in an area located 40 km from the power plant. Leachable (137)Cs loss was modeled by a double exponential (DE) model. This model could not reproduce the variation in activity concentration observed. In order to refine the DE model, the main physical measurable parameters (rainfall intensity, wind velocity, and snowfall occurrence) were assessed, and rainfall was identified as the dominant factor controlling observed variation. A corrective factor was then developed to incorporate rainfall intensity in an improved DE model. With the original DE model, we estimated total (137)Cs loss by leaching from canopies to be 72 ± 4%, 67 ± 4%, and 48 ± 2% of the total plume deposition under mature cedar, young cedar, and broad-leaf forests, respectively. In contrast, with the improved DE model, the total (137)Cs loss by leaching was estimated to be 34 ± 2%, 34 ± 2%, and 16 ± 1% of the total plume deposition under mature cedar, young cedar, and broad-leaf forests, respectively. The improved DE model corresponds better to observed data in literature. Understanding (137)Cs and (134)Cs forest dynamics is important for forecasting future contamination of forest soils around the FDNPP. It also provides a basis for understanding forest transfers in future potential nuclear disasters.

  13. Desorption of 137Cs from Brachythecium mildeanum moss using acid solutions with pH 4.60-6.50

    NASA Astrophysics Data System (ADS)

    Čučulović, Ana; Veselinović, Dragan

    2015-12-01

    The desorption of 137Cs from the moss Brachythecium mildeanum (Schimp.) was performed using the following solutions: H2SO4 ( I), HNO3 ( II), H2SO4 + HNO3 ( III) with pH values of 4.60, 5.15, and 5.75, respectively, as well as distilled water (D) with pH 6.50. After five successive desorptions, each lasting 24 h, 20.5-37.6% 137Cs was desorbed from the moss using these solutions, while 30.7% of the starting content was desorbed using distilled water. The first desorption removed the highest percent of the original content of 137Cs in the moss (11.3-18.4%). This was determined by measuring 137Cs activity. If the current results are compared with those obtained earlier it may be concluded that 137Cs desorption from mosses is not species-dependent. The obtained results indicate the necessity of investigating the influence of acid rain, or rather, of H+ ions, on desorption of other ions from biological systems, i.e., the role of H+ ions in spreading other polluting compounds and thus producing secondary environmental pollution. From the results of this study it follows that acid rain will lead, through H+ ion action, to a similar increasing pollution of fallout waters with other ionic compounds which may not be present in the water before the contact with the plants and thus enable the pollution spreading. In the investigated system, the replacement of H+ ions from acid rains by more dangerous radioactive ions occured, increasing the concentration of the radioactive ions in the water, which demonstrates that the same process takes place in fallout water.

  14. Role of plants in the spatial differentiation of 137Cs and 90Sr statuses on the aggregate level

    NASA Astrophysics Data System (ADS)

    Fokin, A. D.; Torshin, S. P.; Bebneva, Yu. M.; Gadzhiagaeva, R. A.; Taldykina, L. G.

    2016-04-01

    The increased concentration of an element in plant biomass compared to the soil mass is an essential condition for the differentiated spatial distribution and status of the element on the aggregate level. Two forms of this differentiation have been revealed for 137Cs and 90Sr. Transfer of 137Cs from plant roots and concentration on the surface of soil aggregates have been established experimentally. Indirect data also point to the potential localization of 137Cs on the surface of intraaggregate pores. The effect of radionuclide concentrating on the outer and inner surfaces of aggregates is due to the rapid and strong fixation of cesium microamounts by mineral soil components. 137Cs from the surface of aggregates is more available for the repeated uptake by plant roots than from the intraped mass. The distortion of this spatial differentiation mainly occurs during the reaggregation of soil mass, which in turn decreases the availability of the radionuclide to plants. For 90Sr, its elevated concentration in the form of organic residues has been revealed in the inter- and intraaggregate pore space. However, due to the high diffusion rate, 90Sr is relatively rapidly (during several months under pot experimental conditions) redistributed throughout the entire volume of soil aggregates and its major part gradually passes into the phase of humic compounds, to which the radionuclide is bound by exchange sorption. The high level of the next root uptake (higher than for 137Cs by one to two orders of magnitude) favors the permanent renewal of loci with increased 90Sr concentrations in the inter- and intraaggregate pore space in the form of plant residues.

  15. Combining multiple fallout radionuclides (137Cs, 7Be, 210Pbxs) improves our understanding of sediment source dynamics in tropical rivers

    NASA Astrophysics Data System (ADS)

    Evrard, O.; Laceby, J. P.; Huon, S.; Lefèvre, I.; Sengtaheuanghoung, O.; Ribolzi, O.

    2015-12-01

    Soil erosion has accelerated as a result of land use change, increasing the sediment supply to rivers worldwide. A thorough knowledge of sediment dynamics is required to design efficient management measures to control erosion and reduce sediment delivery from catchments. Fallout radionuclides are often used separately to provide spatial (137Cs) or temporal (7Be, 210Pbxs) information on sediment sources. In this study, we examine their combined application to simultaneously model spatial and temporal sediment source dynamics. To this end, potential sediment sources (n=84) and suspended sediment (n=16) were collected at two stations in a 12 km² catchment in Northern Laos during the first flood of the 2014 wet season. Part of the source material was directly sampled in ephemeral flow occurring on hillslopes to avoid the grain size selectivity problems that may occur during erosion and river transport processes. A distribution modelling approach quantified the relative contributions of recently eroded surface (labelled with both 7Be and 137Cs), recently eroded subsurface (depleted in both 7Be and 137Cs), re-suspended surface (depleted in 7Be and labelled with 137Cs) and re-suspended subsurface sources (enriched in 7Be and depleted in 137Cs). At an upstream sampling location, surface sources contributed the majority of sediment (55%) whereas subsurface sources dominated the supply of sediment downstream (74%). Importantly, re-suspended subsurface sources, labelled with 7Be, were a significant sediment source at the catchment outlet (60%). This approach demonstrates the utility of combining multiple radionuclides when investigating spatial and temporal sediment source dynamics in tropical catchments. In the future, sampling of source material in ephemeral flows occurring on hillslopes should be encouraged. Furthermore, the proposed approach should be tested in larger catchments to guide the implementation of efficient erosion control measures.

  16. Fukushima simulation experiment: assessing the effects of chronic low-dose-rate internal 137Cs radiation exposure on litter size, sex ratio, and biokinetics in mice.

    PubMed

    Nakajima, Hiroo; Yamaguchi, Yoshiaki; Yoshimura, Takashi; Fukumoto, Manabu; Todo, Takeshi

    2015-12-01

    To investigate the transgenerational effects of chronic low-dose-rate internal radiation exposure after the Fukushima Daiichi Nuclear Power Plant accident in Japan, 18 generations of mice were maintained in a radioisotope facility, with free access to drinking water containing (137)CsCl (0 and 100 Bq/ml). The (137)Cs distribution in the organs of the mice was measured after long-term ad libitum intake of the (137)CsCl water. The litter size and the sex ratio of the group ingesting the (137)Cs water were compared with those of the control group, for all 18 generations of mice. No significant difference was noted in the litter size or the sex ratio between the mice in the control group and those in the group ingesting the (137)Cs water. The fixed internal exposure doses were ∼160 Bq/g and 80 Bq/g in the muscles and other organs, respectively. PMID:26825299

  17. Fukushima simulation experiment: assessing the effects of chronic low-dose-rate internal 137Cs radiation exposure on litter size, sex ratio, and biokinetics in mice

    PubMed Central

    Nakajima, Hiroo; Yamaguchi, Yoshiaki; Yoshimura, Takashi; Fukumoto, Manabu; Todo, Takeshi

    2015-01-01

    To investigate the transgenerational effects of chronic low-dose-rate internal radiation exposure after the Fukushima Daiichi Nuclear Power Plant accident in Japan, 18 generations of mice were maintained in a radioisotope facility, with free access to drinking water containing 137CsCl (0 and 100 Bq/ml). The 137Cs distribution in the organs of the mice was measured after long-term ad libitum intake of the 137CsCl water. The litter size and the sex ratio of the group ingesting the 137Cs water were compared with those of the control group, for all 18 generations of mice. No significant difference was noted in the litter size or the sex ratio between the mice in the control group and those in the group ingesting the 137Cs water. The fixed internal exposure doses were ∼160 Bq/g and 80 Bq/g in the muscles and other organs, respectively. PMID:26825299

  18. Update global budget of 134Cs and 137Cs derived from Fukushima NPP1 accident

    NASA Astrophysics Data System (ADS)

    Aoyama, Michio; Tsumune, Daisuke; Tsubono, Takaki; Misuimi, Kazuhiro; Inomata, Yayoi; Kumamoto, Yuichiro; Hamajima, Yasunori

    2014-05-01

    134Cs and 137Cs, hereafter radiocaesium, were released from the Fukushima NPP1 accident on March 2011 and to evaluate total amount of released radiocaesium is essential to assess impacts of released radiocaesium to iur environment. We however still have wide range of reports about total amount of released radiocaesium after the accident till today. Released radiocasium were injected in the North Pacific Ocean by two major pathways, direct discharge from the accident site and atmospheric pathway to the ocean while there was only atmospheric deposition on land. We summarize estimations of budget of radiocasium based on both observations and model studies for land deposition, deposition on the North Pacific Ocean and inventory in the North Pacific Ocean, an inventory of sediment close to the site. The major portion of released radiocaesium can be believed to be deposited mainly in the western North Pacific Ocean because deposition density at west coast of US continent was only at an order of 100 Bq m-2 while that at close to accident site was MBq m-2. An inventory in the North Pacific Ocean by some of the authors was 15-18 PBq on April-May 2011 by model-observation comparison and that in the mode water in the western North Pacific Ocean based on the observations on January- February 2012 was 6 PBq. The second portion might be on main land Japan and it is rather easy to evaluate total amount of deposited radiocaesium because there are good observation both by direct sampling of soil and aerial survey. A result of integration for land deposition was about 2.5 PBq. The third portion is in the sediment and an inventory in the sediment by observation showed 42 TBq at close to the site while the total inventory of 137Cs in sediments off the Fukushima coast is thus estimated to be the order of 0.1 PBq by a model study by some of the authors. Estimations of direct discharge from the site also still varied much from 3 PBq to 27 PBq. Two larger estimations did the backward

  19. The disequilibrium between 210Po and 210Pb in raw and drinking waters.

    PubMed

    Idoeta, R; Herranz, M; Legarda, F

    2011-01-01

    Many countries have to monitor and control the radioactivity in drinking waters in order to ensure compliance with the requirements of their respective regulations. Among radionuclides responsible for this radioactivity there are (210)Po and (210)Pb, which are usually not in radioactive equilibrium in waters. This paper deals with the analysis of this disequilibrium and the way that the water treatment plants affect it. To do this, (210)Po and (210)Pb activity concentrations were measured in raw and drinking water. The measurements were performed by alpha-particle spectrometry and gas flow proportional counting and the corresponding formulae for uncertainties and detection limits are presented. The values obtained show that the Po/Pb ratio is lower in surface than in ground waters. Regarding water treatment, this ratio adopts values lower in drinking water than in raw waters. In any case, for the waters analysed in this work the committed effective doses due to these radionuclides, are negligible.

  20. Degassing Mechanisms and Timescales of Implied by (210Pb) Values for Andesites Erupted from Arenal Volcano

    NASA Astrophysics Data System (ADS)

    Reagan, M. K.; Tepley, F. J.; Gill, J. B.; Lundstrom, C.

    2004-12-01

    The ongoing eruption of Arenal, which began in 1968, is an ideal laboratory for investigating magmatic processes that occur over short time periods during eruptions. To identify and place time constraints on these processes, lavas from throughout this eruption have been analyzed for (210Pb) (t1/2 = 22.6 y). Because Pb is both incompatible and only weakly volatile, variations in (210Pb)/(226Ra) largely monitor decade-scale fluxes of 222Rn through magmas. At present, only one lava has been analyzed for 226Ra, and the following discussion assumes that Ra varies in concert with other highly incompatible elements in Arenal lavas. By meeting time, additional whole rock 226Ra values will be available to further constrain this discussion. The eruption has been divided into two principal stages based on variations in bulk composition (Ryder, C., 2004, MS Thesis, UCSC). The first stage lasted from the beginning of the eruption until the early 1970s when Pb isotopes shifted. This shift marked the end of the eruption from one reservoir and the appearance of a new magma presumably from a deeper chamber. Lavas and tephras erupted in 1968 have small excesses in 210Pb over calculated 226Ra values, whereas those erupted in 1969 have 210Pb deficits. These data are consistent with decade-scale transfer of 222Rn from the less-differentiated lower portion of the original magma reservoir to the more differentiated and more phenocryst poor upper reservoir. This could occur either by diffusion of 222Rn through the melt within the chamber or by transfer in a separate gas phase in vapor saturated magma. In 1971, just before the shift in Pb isotopes, lavas erupted with an approximately 2-fold 210Pb excess over 226Ra, which suggests that the deeper magma that eventually erupted and shifted Pb-isotope values contributed volatiles to the lower portion of the original reservoir. If the excess in 1971 was due to 222Rn fluxing since 1968, then the average (222Rn)/( 226Ra) in the lava-gas mixture

  1. Minimum speed limit for ocean ridge magmatism from 210Pb-226Ra-230Th disequilibria

    NASA Astrophysics Data System (ADS)

    Rubin, K. H.; van der Zander, I.; Smith, M. C.; Bergmanis, E. C.

    2005-09-01

    Although 70 per cent of global crustal magmatism occurs at mid-ocean ridges-where the heat budget controls crustal structure, hydrothermal activity and a vibrant biosphere-the tempo of magmatic inputs in these regions remains poorly understood. Such timescales can be assessed, however, with natural radioactive-decay-chain nuclides, because chemical disruption to secular equilibrium systems initiates parent-daughter disequilibria, which re-equilibrate by the shorter half-life in a pair. Here we use 210Pb-226Ra-230Th radioactive disequilibria and other geochemical attributes in oceanic basalts less than 20 years old to infer that melts of the Earth's mantle can be transported, accumulated and erupted in a few decades. This implies that magmatic conditions can fluctuate rapidly at ridge volcanoes. 210Pb deficits of up to 15 per cent relative to 226Ra occur in normal mid-ocean ridge basalts, with the largest deficits in the most magnesium-rich lavas. The 22-year half-life of 210Pb requires very recent fractionation of these two uranium-series nuclides. Relationships between 210Pb-deficits, (226Ra/230Th) activity ratios and compatible trace-element ratios preclude crustal-magma differentiation or daughter-isotope degassing as the main causes for the signal. A mantle-melting model can simulate observed disequilibria but preservation requires a subsequent mechanism to transport melt rapidly. The likelihood of magmatic disequilibria occurring before melt enters shallow crustal magma bodies also limits differentiation and heat replenishment timescales to decades at the localities studied.

  2. Atmospheric 210Pb and anthropogenic trace metals in the continental outflow to the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Bikkina, Srinivas; Sarin, M. M.; Chinni, Venkatesh

    2015-12-01

    Atmospheric 210Pb and trace metals (Pb, Cd, Cu, Mn, Cr, Co, Ni and Zn) have been studied in fine mode aerosols (PM2.5) from a sampling site (Kharagpur: 22.3°N, 87.3°E) in the Indo-Gangetic Plain (IGP) during the continental outflow (November-March) to the Bay of Bengal (BoB). The aerosol 210Pb activity (1.3-6.6 mBq m-3) is significantly high in the wintertime (December-January) compared to model based data in the literature. The cause for higher 210Pb activity is attributed to enhanced 222Rn emanation from Alluvium in the IGP as well as lower boundary layer height. The trace metal concentrations (in ng m-3) also exhibit pronounced temporal variability (Pb: 8-296, Mn: 8-568, Cr: 4.5-33, Cu: 2.1-29.3, Ni: 2.3-14.3, Co: 0.5-1.6 and Cd: 1-29.5) and are of comparable magnitude with those documented over the BoB (Srinivas and Sarin, 2013b), suggesting dominant impact of IGP-outflow on marine atmospheric boundary layer. The enrichment factors (EFcrust) of Pb, Cd, Cu, Mn, Cr, Co and Ni in PM2.5, relative to upper continental crust, varied as 105-1561, 1265-24006, 13-87, 3-99, 7-27, 3-19 and 9-27, respectively. Significant linear relationship among trace metals and chemical species (non-sea-salt-K+, nss-SO42- and EC) emphasizes their anthropogenic source. The high concentrations and EFcrust of Pb, Cd and Cu, together with residence time of PM2.5 (2-13 days, assessed from 210Pb) in the IGP-outflow has implications to increase in the aerosol toxicity and their impact on biogeochemistry of ocean surface waters via air-sea deposition.

  3. Minimum speed limit for ocean ridge magmatism from 210Pb-226Ra-230Th disequilibria.

    PubMed

    Rubin, K H; van der Zander, I; Smith, M C; Bergmanis, E C

    2005-09-22

    Although 70 per cent of global crustal magmatism occurs at mid-ocean ridges-where the heat budget controls crustal structure, hydrothermal activity and a vibrant biosphere-the tempo of magmatic inputs in these regions remains poorly understood. Such timescales can be assessed, however, with natural radioactive-decay-chain nuclides, because chemical disruption to secular equilibrium systems initiates parent-daughter disequilibria, which re-equilibrate by the shorter half-life in a pair. Here we use 210Pb-226Ra-230Th radioactive disequilibria and other geochemical attributes in oceanic basalts less than 20 years old to infer that melts of the Earth's mantle can be transported, accumulated and erupted in a few decades. This implies that magmatic conditions can fluctuate rapidly at ridge volcanoes. 210Pb deficits of up to 15 per cent relative to 226Ra occur in normal mid-ocean ridge basalts, with the largest deficits in the most magnesium-rich lavas. The 22-year half-life of 210Pb requires very recent fractionation of these two uranium-series nuclides. Relationships between 210Pb-deficits, (226Ra/230Th) activity ratios and compatible trace-element ratios preclude crustal-magma differentiation or daughter-isotope degassing as the main causes for the signal. A mantle-melting model can simulate observed disequilibria but preservation requires a subsequent mechanism to transport melt rapidly. The likelihood of magmatic disequilibria occurring before melt enters shallow crustal magma bodies also limits differentiation and heat replenishment timescales to decades at the localities studied.

  4. 238U, 226Ra and 210Pb in some vent waters of the Galapagos Spreading Center

    NASA Astrophysics Data System (ADS)

    Krishnaswami, S.; Turekian, K. K.

    1982-08-01

    The concentrations of 226Ra, 238U and 210Pb have been measured in waters from the Mussel Bed and the Rose Garden thermal fields at the Galapagos spreading center over a temperature range of ˜2.5-16°C. The 226Ra-T plots yield slopes of 0.112 and 0.036 dpm/kg°C for the Mussel Bed and the Rose Garden respectively yielding a global hydrothermal 226Ra flux less than 5% of that required to sustain the oceanic inventory. 238U concentration in waters <9°C is the same as that in ambient sea water whereas water hotter than ˜9°C shows a decreasing trend with temperature to zero 238U at ˜29°C. 210Pb concentration in Mussel Bed increases with temperature, and extrapolated to ˜350°C yields a 210Pb concentration considerably less than that expected from 222Rn decay and basalt alteration.

  5. Technologically enhanced 210Pb and 210Po in iron and steel industry.

    PubMed

    Khater, Ashraf E M; Bakr, Wafaa F

    2011-05-01

    Iron and steel manufacture has been ranked as the largest industrial source of environmental contamination in the USA; the wastes generated in their production processes contain heavy elements that can be a source of contamination, and natural radionuclides that can produce an occupational and/or public radiological impact. In this work the potential occupational effective dose rate (μSv/y) due to inhalation in four integrated steel-making factories from Egypt has been evaluated, by assuming a well defined scenario and with basis in the (210)Pb and (210)Po activity concentrations determined in ore and wastes collected in the aforementioned factories. Activity concentrations, in Bq/kg, of (210)Pb and (210)Po, and leachable Pb and Fe were measured using gamma-ray spectrometry based on HPGe detector, alpha particle spectrometry based on PIPS detector, and inductively coupled plasma-mass spectrometry (ICP-MS). Levels of (210)Pb and (210)Po in the range of

  6. Dating human skeletal remains using 90Sr and 210Pb: case studies.

    PubMed

    Schrag, Bettina; Uldin, Tanya; Mangin, Patrice; Bochud, François; Froidevaux, Pascal

    2014-01-01

    In legal medicine, the post mortem interval (PMI) of interest covers the last 50 years. When only human skeletal remains are found, determining the PMI currently relies mostly on the experience of the forensic anthropologist, with few techniques available to help. Recently, several radiometric methods have been proposed to reveal PMI. For instance, (14)C and (90)Sr bomb pulse dating covers the last 60 years and give reliable PMI when teeth or bones are available. (232)Th series dating has also been proposed but requires a large amount of bones. In addition, (210)Pb dating is promising but is submitted to diagenesis and individual habits like smoking that must be handled carefully. Here we determine PMI on 29 cases of forensic interest using (90)Sr bomb pulse. In 12 cases, (210)Pb dating was added to narrow the PMI interval. In addition, anthropological investigations were carried out on 15 cases to confront anthropological expertise to the radiometric method. Results show that 10 of the 29 cases can be discarded as having no forensic interest (PMI>50 years) based only on the (90)Sr bomb pulse dating. For 10 other cases, the additional (210)Pb dating restricts the PMI uncertainty to a few years. In 15 cases, anthropological investigations corroborate the radiometric PMI. This study also shows that diagenesis and inter-individual difference in radionuclide uptake represent the main sources of uncertainty in the PMI determination using radiometric methods.

  7. Behaviour of oceanic 137Cs following the Fukushima Daiichi Nuclear Power Plant accident for four years simulated numerically by a regional ocean model

    NASA Astrophysics Data System (ADS)

    Torn, M. S.; Koven, C. D.; Riley, W. J.; Zhu, B.; Hicks Pries, C.; Phillips, C. L.

    2014-12-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant (1F NPP) following the earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways, direct release from the accident site and atmospheric deposition.We reconstructed spatiotemporal variability of 137Cs activity in the regional ocean for four years by numerical model, such as a regional scale and the North Pacific scale oceanic dispersion models, an atmospheric transport model, a sediment transport model, a dynamic biological compartment model for marine biota and river runoff model. Direct release rate of 137Cs were estimated for four years after the accident by comparing simulated results and observed activities very close to the site. The estimated total amounts of directly release was 3.6±0.7 PBq. Directly release rate of 137Cs decreased exponentially with time by the end of December 2012 and then, was almost constant. Decrease rate were quite small after 2013. The daily release rate of 137Cs was estimated to be the order of magnitude of 1010 Bq/day by the end of March 2015. The activity of directly released 137Cs was detectable only in the coastal zone after December 2012. Simulated 137Cs activities attributable to direct release were in good agreement with observed activities, a result that implies the estimated direct release rate was reasonable. There is no observed data of 137Cs activity in the ocean from 11 to 21 March 2011. Observed data of marine biota should reflect the history of 137Cs activity in this early period. We reconstructed the history of 137Cs activity in this early period by considering atmospheric deposition, river input, rain water runoff from the 1F NPP site. The comparisons between simulated 137Cs activity of marine biota by a dynamic biological compartment and observed data also suggest that simulated 137Cs activity attributable to atmospheric deposition was underestimated in this early period. The

  8. Behaviour of oceanic 137Cs following the Fukushima Daiichi Nuclear Power Plant accident for four years simulated numerically by a regional ocean model

    NASA Astrophysics Data System (ADS)

    Tsumune, D.; Tsubono, T.; Aoyama, M.; Misumi, K.; Tateda, Y.

    2015-12-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant (1F NPP) following the earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways, direct release from the accident site and atmospheric deposition.We reconstructed spatiotemporal variability of 137Cs activity in the regional ocean for four years by numerical model, such as a regional scale and the North Pacific scale oceanic dispersion models, an atmospheric transport model, a sediment transport model, a dynamic biological compartment model for marine biota and river runoff model. Direct release rate of 137Cs were estimated for four years after the accident by comparing simulated results and observed activities very close to the site. The estimated total amounts of directly release was 3.6±0.7 PBq. Directly release rate of 137Cs decreased exponentially with time by the end of December 2012 and then, was almost constant. Decrease rate were quite small after 2013. The daily release rate of 137Cs was estimated to be the order of magnitude of 1010 Bq/day by the end of March 2015. The activity of directly released 137Cs was detectable only in the coastal zone after December 2012. Simulated 137Cs activities attributable to direct release were in good agreement with observed activities, a result that implies the estimated direct release rate was reasonable. There is no observed data of 137Cs activity in the ocean from 11 to 21 March 2011. Observed data of marine biota should reflect the history of 137Cs activity in this early period. We reconstructed the history of 137Cs activity in this early period by considering atmospheric deposition, river input, rain water runoff from the 1F NPP site. The comparisons between simulated 137Cs activity of marine biota by a dynamic biological compartment and observed data also suggest that simulated 137Cs activity attributable to atmospheric deposition was underestimated in this early period. The

  9. The Fukushima-137Cs deposition case study: properties of the multi-model ensemble.

    PubMed

    Solazzo, E; Galmarini, S

    2015-01-01

    In this paper we analyse the properties of an eighteen-member ensemble generated by the combination of five atmospheric dispersion modelling systems and six meteorological data sets. The models have been applied to the total deposition of (137)Cs, following the nuclear accident of the Fukushima power plant in March 2011. Analysis is carried out with the scope of determining whether the ensemble is reliable, sufficiently diverse and if its accuracy and precision can be improved. Although ensemble practice is becoming more and more popular in many geophysical applications, good practice guidelines are missing as to how models should be combined for the ensembles to offer an improvement over single model realisations. We show that the ensemble of models share large portions of bias and variance and make use of several techniques to further show that subsets of models can explain the same amount of variance as the full ensemble mean with the advantage of being poorly correlated, allowing to save computational resources and reduce noise (and thus improving accuracy). We further propose and discuss two methods for selecting subsets of skilful and diverse members, and prove that, in the contingency of the present analysis, their mean outscores the full ensemble mean in terms of both accuracy (error) and precision (variance). PMID:24666629

  10. Assessment of natural radioactivity and (137)Cs in some coastal areas of the Saudi Arabian gulf.

    PubMed

    Al-Ghamdi, H; Al-Muqrin, A; El-Sharkawy, A

    2016-03-15

    The levels of natural radioactivity have been investigated in some Saudi Arabian Gulf coastal areas. Sampling sites were chosen according to the presence of nearby non-nuclear industrial activities such as, the two main water desalination plants in Al Khobar and Al Jubail, and Maaden phosphate complex in Ras Al Khair, to ensure that effluents discharges into the Arabian Gulf didn't enhance radioactivity in seawater and shore sediments. Seawater samples were analyzed for radium isotopes (Ra-226 & Ra-228) and measured by gamma spectrometry using high purity germanium detector, after radiochemical separation of the isotopes by co-precipitation with MnO2. Shore sediment samples were analyzed for (226)Ra, (228)Ra ((232)Th), (4)°K and (137)Cs using gamma sepectrometry. A small variation was observed in the activity concentrations of the investigated radioisotopes, and the activity levels were comparable to those reported in literature. Quality assurance and methods validation were established through the efficiency calibration of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference materials and the intercomparison and proficiency tests. Radiological hazards were assessed, and the annual effective dose had an average value of 0.02 mSv. On the basis of the current results, we may conclude that any radiological hazards to the public visiting these shores are not expected. PMID:26895593

  11. Distribution of radioactive cesium ((134)Cs plus (137)Cs) in rice fractions during polishing and cooking.

    PubMed

    Hachinohe, Mayumi; Okunishi, Tomoya; Hagiwara, Shoji; Todoriki, Setsuko; Kawamoto, Shinichi; Hamamatsu, Shioka

    2015-03-01

    We investigated the distribution of cesium-134 ((134)Cs) and cesium-137 ((137)Cs) during polishing and cooking of rice to obtain their processing factors (Pf) and food processing retention factors (Fr) to make the information available for an adequate understanding of radioactive Cs dynamics. Polishing brown rice resulted in a decreased radioactive Cs concentration of the polished rice, but the bran and germ (outer layers) exhibited higher concentrations than brown rice. The Pf values for 100% polished rice and outer layers ranged from 0.47 to 0.48 and 6.5 to 7.8, respectively. The Fr values for 100% polished rice and outer layers were 0.43 and 0.58 to 0.60, respectively. The distribution of radioactive Cs in polished rice and outer layers was estimated at approximately 40 and 60%, respectively. On the other hand, cooked rice showed significantly lower levels of radioactive Cs than polished rice, and transfer of radioactive Cs into wash water was observed. The Pf and Fr values for cooked rice were 0.28 and 0.65 to 0.66, respectively. From these results, we can calculate that if the radioactive Cs concentration in brown rice is 100 Bq/kg, the concentrations of Cs in polished rice and cooked rice will be 47 to 48 Bq/kg and 13 Bq/kg, respectively. PMID:25719881

  12. Assessment of natural radioactivity and (137)Cs in some coastal areas of the Saudi Arabian gulf.

    PubMed

    Al-Ghamdi, H; Al-Muqrin, A; El-Sharkawy, A

    2016-03-15

    The levels of natural radioactivity have been investigated in some Saudi Arabian Gulf coastal areas. Sampling sites were chosen according to the presence of nearby non-nuclear industrial activities such as, the two main water desalination plants in Al Khobar and Al Jubail, and Maaden phosphate complex in Ras Al Khair, to ensure that effluents discharges into the Arabian Gulf didn't enhance radioactivity in seawater and shore sediments. Seawater samples were analyzed for radium isotopes (Ra-226 & Ra-228) and measured by gamma spectrometry using high purity germanium detector, after radiochemical separation of the isotopes by co-precipitation with MnO2. Shore sediment samples were analyzed for (226)Ra, (228)Ra ((232)Th), (4)°K and (137)Cs using gamma sepectrometry. A small variation was observed in the activity concentrations of the investigated radioisotopes, and the activity levels were comparable to those reported in literature. Quality assurance and methods validation were established through the efficiency calibration of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference materials and the intercomparison and proficiency tests. Radiological hazards were assessed, and the annual effective dose had an average value of 0.02 mSv. On the basis of the current results, we may conclude that any radiological hazards to the public visiting these shores are not expected.

  13. Mortality of the harvester ant (Pogonomyrmex owyheei) after exposure to /sup 137/Cs gamma radiation

    SciTech Connect

    Gano, K.A.

    1981-01-01

    Harvester ants, Pogonomyrmex owyheei Cole, irradiated with 3.5 kR to 268 kR of /sup 137/Cs gamma radiation, were maintained at simulated summer (27/sup 0/C) and winter (7/sup 0/C) temperature regimes. After thirty days, the cool series was warmed to 27/sup 0/C and observed for mortality along with the warm series.Though mortality was delayed in the cool series, each series reached 50% mortality at similar rates. Because the harvester ant is extremely tolerant to radiation and experimental rates used far exceed possible environmental exposure, it is unlikely that ant colonies dwelling among low-level nuclear waste storage sites will be deleteriously affected by radiation. This species has the capability of tunneling to a depth well within the range of some buried waste. Since these harvester ants are potential transporters of buried waste, they should be considered as a biotic factor in radioactive waste management operations in semi-arid regions.

  14. Mortality of the harvester ant (Pogonomyrmex owyheei) after exposure to /sup 137/Cs gamma radiation

    SciTech Connect

    Gano, K.A.

    1981-01-01

    Harvester ants, Pogonomyrmex owyheei Cole, irradiated with 3.5 kR to 268 kR of /sup 137/Cs gamma radiation, were maintained at simulated summer (27/sup 0/C) and winter (7/sup 0/C) temperature regimes. After thirty days, the cool series was warmed to 27/sup 0/C and observed for mortality along with the warm series. Though mortality was delayed in the cool series, each series reached 50% mortality at similar rates. Because the harvester ant is extremely tolerant to radiation and experimental rates used far exceed possible environmental exposure, it is unlikely that ant colonies dwelling among low-level nuclear waste storage sites will be deleteriously affected by radiation. This species has the capability of tunneling to a depth well within the range of some buried waste. Since these harvester ants are potential transporters of buried waste, they should be considered as a biotic factor in radioactive waste management operations in semi-arid regions.

  15. Distribution and turnover of (137)Cs in birch forest ecosystems: influence of precipitation chemistry.

    PubMed

    Thørring, H; Skuterud, L; Steinnes, E

    2012-08-01

    The aim of the present work was to study radioactive caesium in soil and plants from birch forests subject to different chemical climate. Four areas and three types of precipitation regimes were considered, representing a natural climatic range found in Norway: (A) acidic precipitation (southernmost part of the country); (B) precipitation rich in "sea salts"/marine cations (coastal areas); and (C) + (D) low concentrations of sea salts (inland areas). The results showed significant regional differences in plant uptake between the investigated areas. For instance the aggregated soil-to-plant transfer coefficients (Tag) were generally up to 7-8 times higher for the area receiving acid rain. Differences in caesium speciation partly explained the regional variability - e.g. the exchangeable fraction ranged from 1 to 40% (with the largest fraction of exchangeable caesium found in southernmost Norway). Transfer coefficients estimated on the basis of exchangeable fractions showed no significant differences between the areas of highest (A) and lowest (C) Tags. However, exchangeable fractions taken into consideration, the uptake of (137)Cs in plants in the acid rain-influenced area is still about twice that in the sea salt influenced area B. A significantly lower concentration of soluble base cations and a higher share of acid components in soils in area A is a likely explanation for this observation.

  16. Current response of a TlBr detector to {sup 137}Cs {gamma}-ray radiation

    SciTech Connect

    Gazizov, I. M.; Zaletin, V. M.; Kukushkin, V. M.; Khrunov, V. S.

    2011-05-15

    The current response of a TlBr detector to {sup 137}Cs {gamma}-ray radiation has been studied in the dose-rate range 0.033-3.84 Gy/min and within the voltage range 1-300 V; the detectors are based on pure and doped TlBr crystals grown from the melt by the Bridgman-Stockbarger method. The mass fraction of Pb or Ca introduced into the TlBr crystals was 1-10 ppm for Pb and 150 ppm for Ca. The current response of nominally undoped TlBr samples was nearly linear over two decades of studied dose rates. Deep hole levels associated with cationic vacancies V{sub c}{sup -} determine the dependence of the current response on the voltage in the high electric fields. The parameters of the carriers' transport {mu}{tau} are determined. The TlBr crystals grown in vacuum and in the bromine vapor exhibit a large mobility-lifetime product of 4.3 Multiplication-Sign 10{sup -4} and 6.4 Multiplication-Sign 10{sup -5} cm{sup 2}V{sup -1}, respectively. The value of {mu}{tau} is in the range (4-9) Multiplication-Sign 10{sup -5} cm{sup 2}V{sup -1} for crystals doped with a divalent cation.

  17. Distribution and turnover of (137)Cs in birch forest ecosystems: influence of precipitation chemistry.

    PubMed

    Thørring, H; Skuterud, L; Steinnes, E

    2012-08-01

    The aim of the present work was to study radioactive caesium in soil and plants from birch forests subject to different chemical climate. Four areas and three types of precipitation regimes were considered, representing a natural climatic range found in Norway: (A) acidic precipitation (southernmost part of the country); (B) precipitation rich in "sea salts"/marine cations (coastal areas); and (C) + (D) low concentrations of sea salts (inland areas). The results showed significant regional differences in plant uptake between the investigated areas. For instance the aggregated soil-to-plant transfer coefficients (Tag) were generally up to 7-8 times higher for the area receiving acid rain. Differences in caesium speciation partly explained the regional variability - e.g. the exchangeable fraction ranged from 1 to 40% (with the largest fraction of exchangeable caesium found in southernmost Norway). Transfer coefficients estimated on the basis of exchangeable fractions showed no significant differences between the areas of highest (A) and lowest (C) Tags. However, exchangeable fractions taken into consideration, the uptake of (137)Cs in plants in the acid rain-influenced area is still about twice that in the sea salt influenced area B. A significantly lower concentration of soluble base cations and a higher share of acid components in soils in area A is a likely explanation for this observation. PMID:22388272

  18. Distribution of radioactive cesium ((134)Cs plus (137)Cs) in rice fractions during polishing and cooking.

    PubMed

    Hachinohe, Mayumi; Okunishi, Tomoya; Hagiwara, Shoji; Todoriki, Setsuko; Kawamoto, Shinichi; Hamamatsu, Shioka

    2015-03-01

    We investigated the distribution of cesium-134 ((134)Cs) and cesium-137 ((137)Cs) during polishing and cooking of rice to obtain their processing factors (Pf) and food processing retention factors (Fr) to make the information available for an adequate understanding of radioactive Cs dynamics. Polishing brown rice resulted in a decreased radioactive Cs concentration of the polished rice, but the bran and germ (outer layers) exhibited higher concentrations than brown rice. The Pf values for 100% polished rice and outer layers ranged from 0.47 to 0.48 and 6.5 to 7.8, respectively. The Fr values for 100% polished rice and outer layers were 0.43 and 0.58 to 0.60, respectively. The distribution of radioactive Cs in polished rice and outer layers was estimated at approximately 40 and 60%, respectively. On the other hand, cooked rice showed significantly lower levels of radioactive Cs than polished rice, and transfer of radioactive Cs into wash water was observed. The Pf and Fr values for cooked rice were 0.28 and 0.65 to 0.66, respectively. From these results, we can calculate that if the radioactive Cs concentration in brown rice is 100 Bq/kg, the concentrations of Cs in polished rice and cooked rice will be 47 to 48 Bq/kg and 13 Bq/kg, respectively.

  19. Radiocesium ([sup 137]Cs) from the Chernobyl reactor in Eurasian woodcock and earthworms in Norway

    SciTech Connect

    Kalas, J.A. ); Bretten, S.; Njastad, O. ); Byrkjedal, I. )

    1994-01-01

    To understand the ecological effects of the Chernobyl reactor accident, we investigated radiocesium ([sup 137]Cs) levels in Eurasian woodcock (Scolopax rusticola), earthworms (Lambricidae), litter (dead organic materials lying on the ground), humus (beneath litter 2 cm deep), and mineral soil samples (3-6 cm deep) from a heavily effected (20-60 kBq/m[sup 2][1 Bq = 1 nuclear fission/sec]) area in Norway. The highest concentrations measured in earthworms (1988 median = 142 Bq/Kg) and woodcock (1986 median = 730 Bq/kg) for human food (600 Bq/kg fresh mass) only were found in woodcock during 1986. Radiocesium concentrations decreased (P < 0.001) in earthworms (40%) and woodcock (95%) from 1986 to 1990. There was no reduction in total radiocesium in soil over the same period. The relatively high radiocesium concentrations in woodcock during 1986 and the decreasing radiocesium ratio in woodcock to earthworms during the first years following fallout could have been caused by woodcock ingesting abiotic radiocesium with earthworms. The decrease in radiocesium in woodcock and earthworms during the study (1986-90) probably resulted from decreasing bioavailability of radiocesium during the first years after fallout rather than by radiocesium disappearing from the ecosystem. 38 refs., 3 figs., 2 tabs.

  20. Pu and 137Cs in the Yangtze River estuary sediments: distribution and source identification.

    PubMed

    Liu, Zhiyong; Zheng, Jian; Pan, Shaoming; Dong, Wei; Yamada, Masatoshi; Aono, Tatsuo; Guo, Qiuju

    2011-03-01

    Pu isotopes and (137)Cs were analyzed using sector field ICP-MS and γ spectrometry, respectively, in surface sediment and core sediment samples from the Yangtze River estuary. (239+240)Pu activity and (240)Pu/(239)Pu atom ratios (>0.18) shows a generally increasing trend from land to sea and from north to south in the estuary. This spatial distribution pattern indicates that the Pacific Proving Grounds (PPG) source Pu transported by ocean currents was intensively scavenged into the suspended sediment under favorable conditions, and mixed with riverine sediment as the water circulated in the estuary. This process is the main control for the distribution of Pu in the estuary. Moreover, Pu is also an important indicator for monitoring the changes of environmental radioactivity in the estuary as the river basin is currently the site of extensive human activities and the sea level is rising because of global climate changes. For core sediment samples the maximum peak of (239+240)Pu activity was observed at a depth of 172 cm. The sedimentation rate was estimated on the basis of the Pu maximum deposition peak in 1963-1964 to be 4.1 cm/a. The contributions of the PPG close-in fallout Pu (44%) and the riverine Pu (45%) in Yangtze River estuary sediments are equally important for the total Pu deposition in the estuary, which challenges the current hypothesis that the riverine Pu input was the major source of Pu budget in this area.

  1. Sources and distributions of 137Cs, 238Pu, 239,240Pu radionuclides in the north-western Barents Sea.

    PubMed

    Zaborska, Agata; Mietelski, Jerzy Wojciech; Carroll, JoLynn; Papucci, Carlo; Pempkowiak, Janusz

    2010-04-01

    Sediment deposits are the ultimate sink for anthropogenic radionuclides entering the marine environment. The major sources of anthropogenic radionuclides to the Barents Sea are fallout from nuclear weapons tests, long range transport from other seas, and river and non-point freshwater supplies. In this study we investigated activity concentrations, ratios, and inventories of the anthropogenic radionuclides, 137Cs, 238Pu, 239,240Pu in dated sediment cores collected along a north-south transect in the northwestern Barents Sea. The data were used to evaluate the influence of different sources on the derived spatial and temporal patterns of anthropogenic radionuclides in seafloor sediment deposits. Activity concentrations of 137Cs ranged from <0.1 Bq/kg to 10.5 Bq/kg while 239,240Pu ranged from <0.01 Bq/kg to 2.74 Bq/kg and 238Pu activity concentrations ranged from <0.01 Bq/kg to 0.22 Bq/kg. Total inventories of 137Cs ranged from 29.5+/-1.5 Bq/m2 to 152.7+/-5.6 Bq/m2 and for 239,240Pu inventories (6 sediment layers only) ranged from 9.5+/-0.3 Bq/m2 to 29.7+/-0.4 Bq/m2. Source contributions varied among stations and between the investigated radionuclides. The 238Pu/239,240Pu ratios up to 0.18 indicate discharges from nuclear fuel reprocessing plants as a main contributor of plutonium. Based on 238Pu/239,240Pu ratio, it was calculated that up to 19-27% of plutonium is supplied from sources other than atmospheric global fallout. Taking into account Atlantic current flow trajectories and that both activity concentrations and inventories of plutonium negatively correlate with latitude, Sellafield is a major source for the Barents Sea. Concentrations and inventories of 137Cs correlate positively with latitude and negatively with distance from the Svalbard archipelago. The 137Cs concentrations are highest in an area of intensive melting of sea ice formed along the Siberian coast. Thus, sea ice and supplies from Svalbard may be important source of 137Cs to the Barents Sea

  2. Atmospheric residence time of (210)Pb determined from the activity ratios with its daughter radionuclides (210)Bi and (210)Po.

    PubMed

    Semertzidou, P; Piliposian, G T; Appleby, P G

    2016-08-01

    The residence time of (210)Pb created in the atmosphere by the decay of gaseous (222)Rn is a key parameter controlling its distribution and fallout onto the landscape. These in turn are key parameters governing the use of this natural radionuclide for dating and interpreting environmental records stored in natural archives such as lake sediments. One of the principal methods for estimating the atmospheric residence time is through measurements of the activities of the daughter radionuclides (210)Bi and (210)Po, and in particular the (210)Bi/(210)Pb and (210)Po/(210)Pb activity ratios. Calculations used in early empirical studies assumed that these were governed by a simple series of equilibrium equations. This approach does however have two failings; it takes no account of the effect of global circulation on spatial variations in the activity ratios, and no allowance is made for the impact of transport processes across the tropopause. This paper presents a simple model for calculating the distributions of (210)Pb, (210)Bi and (210)Po at northern mid-latitudes (30°-65°N), a region containing almost all the available empirical data. By comparing modelled (210)Bi/(210)Pb activity ratios with empirical data a best estimate for the tropospheric residence time of around 10 days is obtained. This is significantly longer than earlier estimates of between 4 and 7 days. The process whereby (210)Pb is transported into the stratosphere when tropospheric concentrations are high and returned from it when they are low, significantly increases the effective residence time in the atmosphere as a whole. The effect of this is to significantly enhance the long range transport of (210)Pb from its source locations. The impact is illustrated by calculations showing the distribution of (210)Pb fallout versus longitude at northern mid-latitudes. PMID:27132252

  3. Scavenging and fractionation of particle-reactive radioisotopes 7Be, 210Pb and 210Po in the atmosphere

    NASA Astrophysics Data System (ADS)

    Chen, Jinfang; Luo, Shangde; Huang, Yipu

    2016-09-01

    The scavenging and fractionation of 7Be, 210Pb, and 210Po in the atmosphere are investigated by measuring their activities in rainwater collected from 68 rain events during March 2004 to April 2006 at a coastal station of Xiamen, southeastern China. In addition to documenting the large temporal variations in activities, fluxes, and isotope ratios of 7Be, 210Pb and 210Po in rainwater and the role of rainfall intensity in radionuclide scavenging, our results show that an enhanced deposition of 7Be and 210Pb occurs in the spring than in other seasons and is attributed to the "funnel effect" due to the increased atmospheric vertical convective mixing in the spring. This latter hypothesis is further supported by the observed seasonal and inter-annual variations in 7Be/210Pb and 210Po/210Pb ratios showing that the weakening of vertical convective mixing or stratosphere-troposphere exchange (STE) at the study site is linked with the enhancement of summer monsoons. It appears that the rainfall intensity, in connection with the vertical (e.g., STE) and horizontal (summer monsoons) air transport, exerts an important control on the activities, fluxes, and isotope ratios of 7Be, 210Pb, and 210Po in the atmosphere. Application of the observational data to a theoretical model shows that there are significant fractionations among 7Be, 210Pb, and 210Po in the atmosphere, with the scavenging rate constant or reciprocal of the residence time of radionuclide in the atmosphere being 210Pb > 7Be > 210Po. A revised Poet et al. (1972)'s method is proposed for quantitative constraint on the scavenging behavior of radionuclide, aerosols, and aerosol-associated trace pollutants in the atmosphere.

  4. Atmospheric residence time of (210)Pb determined from the activity ratios with its daughter radionuclides (210)Bi and (210)Po.

    PubMed

    Semertzidou, P; Piliposian, G T; Appleby, P G

    2016-08-01

    The residence time of (210)Pb created in the atmosphere by the decay of gaseous (222)Rn is a key parameter controlling its distribution and fallout onto the landscape. These in turn are key parameters governing the use of this natural radionuclide for dating and interpreting environmental records stored in natural archives such as lake sediments. One of the principal methods for estimating the atmospheric residence time is through measurements of the activities of the daughter radionuclides (210)Bi and (210)Po, and in particular the (210)Bi/(210)Pb and (210)Po/(210)Pb activity ratios. Calculations used in early empirical studies assumed that these were governed by a simple series of equilibrium equations. This approach does however have two failings; it takes no account of the effect of global circulation on spatial variations in the activity ratios, and no allowance is made for the impact of transport processes across the tropopause. This paper presents a simple model for calculating the distributions of (210)Pb, (210)Bi and (210)Po at northern mid-latitudes (30°-65°N), a region containing almost all the available empirical data. By comparing modelled (210)Bi/(210)Pb activity ratios with empirical data a best estimate for the tropospheric residence time of around 10 days is obtained. This is significantly longer than earlier estimates of between 4 and 7 days. The process whereby (210)Pb is transported into the stratosphere when tropospheric concentrations are high and returned from it when they are low, significantly increases the effective residence time in the atmosphere as a whole. The effect of this is to significantly enhance the long range transport of (210)Pb from its source locations. The impact is illustrated by calculations showing the distribution of (210)Pb fallout versus longitude at northern mid-latitudes.

  5. Using 137Cs to study spatial patterns of soil erosion and soil organic carbon (SOC) in an agricultural catchment of the typical black soil region, Northeast China.

    PubMed

    Fang, Haiyan; Li, Qiuyan; Sun, Liying; Cai, Qiangguo

    2012-10-01

    Understanding the spatial pattern of soil organic carbon (SOC) is of great importance because of global environmental concerns. Soil erosion and its subsequent redistribution contribute significantly to the redistribution of SOC in agricultural ecosystems. This study investigated the relationships between (137)Cs and SOC over an agricultural landscape, and SOC redistribution was conducted for an agricultural catchment of the black soil region in Northeast China. The spatial patterns of (137)Cs and SOC were greatly affected by the established shelterbelts and the developed ephemeral gullies. (137)Cs were significantly correlated with SOC when (137)Cs were >2000 Bq m(-2), while no relation was observed between them when (137)Cs were <2000 Bq m(-2). Factors other than soil erosion such as vegetative productivity, mineralization of SOC, landscape position and management induced their spatial difference of (137)Cs and SOC. Using (137)Cs technique to directly study SOC dynamics must be cautious in the black soils. The net SOC loss rate across the entire catchment during 1954-2010 was 92.8 kg ha(-1) yr(-1), with around 42% of the eroded SOC being redeposited within the catchment. Such information can help guide shelterbelt establishment or other land management to reduce SOC loss in the agricultural ecosystems.

  6. Atmospheric deposition and riverine load of (90)Sr and (137)Cs to the Gulf of Gdańsk (southern Baltic Sea) in the period 2005-2011.

    PubMed

    Saniewski, Michał; Zalewska, Tamara

    2016-01-01

    In the period 2005-2011 total atmospheric fallout and the riverine input to the Gulf of Gdańsk was 1168.8 GBq of (90)Sr and 424.1 GBq (137)Cs. The major source of both radionuclides to the Gulf of Gdańsk is the Vistula river; its contribution reached 99.7% in the case of (90)Sr and 95.8% regarding (137)Cs. The atmospheric load of (137)Cs, 18.1 GBq, was nearly 4 times bigger than in the case of (90)Sr (3.75 GBq). In the period 2005-2010, the average annual atmospheric load were at the levels 2-3 GBq for (137)Cs and 0.4-0.6 GBq for (90)Sr, while in 2011, due to the Fukuchima Dai-ichi power plant break down, an increase of annual atmospheric loads was noted to 5.3 GBq of (137)Cs and to 0.87 GBq of (90)Sr. The additional loads did not have an increasing effect on the activity concentrations of (137)Cs and (90)Sr in seawater of the Gulf of Gdańsk, where mean activity concentrations in seawater were equal to 31.1 Bq m(-3) and 7.6 Bq m(-3) in the case of (137)Cs and (90)Sr respectively.

  7. The influence of a whole-lake addition of stable cesium on the remobilization of aged 137Cs in a contaminated reservoir.

    PubMed

    Pinder, J E; Hinton, T G; Whicker, F W

    2005-01-01

    To document the short-term dynamics of Cs, 4 kg of (133)Cs were introduced into an 11.4-ha, 157 000 m(3) reservoir previously contaminated with (137)Cs from past reactor operations at the US Department of Energy's Savannah River Site near Aiken, South Carolina, USA. The (133)Cs addition resulted in an increase of 6.1 MBq of (137)Cs (1.9 mug (137)Cs) in the water column over the following 260 days. Possible sources for the increased (137)Cs included (1) release from the sediments, (2) release from the approximately 26 000 kg of aquatic macrophytes that occupied 80% of the reservoir, and (3) wash-in from the pond's watershed. Data are presented to indicate that release from the sediments was the principal source of the (137)Cs increase. The fraction of (137)Cs released from the sediments (0.7%) is consistent with laboratory measurements of (137)Cs desorption from neighboring ponds on the Savannah River Site. PMID:15701385

  8. Assessment of soil contamination by (210)Po and (210)Pb around heavy oil and natural gas fired power plants.

    PubMed

    Al-Masri, M S; Haddad, Kh; Doubal, A W; Awad, I; Al-Khatib, Y

    2014-06-01

    Soil contamination by (210)Pb and (210)Po around heavy oil and natural gas power plants has been investigated; fly and bottom ash containing enhanced levels of (210)Pb and (210)Po were found to be the main source of surface soil contamination. The results showed that (210)Pb and (210)Po in fly-ash (economizer, superheater) is highly enriched with (210)Pb and (210)Po, while bottom-ash (boiler) is depleted. The highest (210)Pb and (210)Po activity concentrations were found to be in economizer ash, whereas the lowest activity concentration was in the recirculator ash. On the other hand, (210)Pb and (210)Po activity concentrations in soil samples were found to be higher inside the plant site area than those samples collected from surrounding areas. The highest levels were found in the vicinity of Mhardeh and Tishreen power plants; both plants are operated by heavy oil and natural fuels, while the lowest values were found to be in those samples collected from Nasrieh power plant, which is only operated by one type of fuel, viz. natural gas. In addition, the levels of surface soil contamination have decreased as the distance from the power plant site center increased.

  9. Assessment of soil contamination by (210)Po and (210)Pb around heavy oil and natural gas fired power plants.

    PubMed

    Al-Masri, M S; Haddad, Kh; Doubal, A W; Awad, I; Al-Khatib, Y

    2014-06-01

    Soil contamination by (210)Pb and (210)Po around heavy oil and natural gas power plants has been investigated; fly and bottom ash containing enhanced levels of (210)Pb and (210)Po were found to be the main source of surface soil contamination. The results showed that (210)Pb and (210)Po in fly-ash (economizer, superheater) is highly enriched with (210)Pb and (210)Po, while bottom-ash (boiler) is depleted. The highest (210)Pb and (210)Po activity concentrations were found to be in economizer ash, whereas the lowest activity concentration was in the recirculator ash. On the other hand, (210)Pb and (210)Po activity concentrations in soil samples were found to be higher inside the plant site area than those samples collected from surrounding areas. The highest levels were found in the vicinity of Mhardeh and Tishreen power plants; both plants are operated by heavy oil and natural fuels, while the lowest values were found to be in those samples collected from Nasrieh power plant, which is only operated by one type of fuel, viz. natural gas. In addition, the levels of surface soil contamination have decreased as the distance from the power plant site center increased. PMID:24602817

  10. Natural radionuclides (210)Po and (210)Pb in the Delaware and Chesapeake Estuaries: modeling scavenging rates and residence times.

    PubMed

    Marsan, D; Rigaud, S; Church, T

    2014-12-01

    During the spring and summer months of 2012, (210)Po and (210)Pb activity were measured in the dissolved and particulate phases from the Delaware and upper Chesapeake estuaries. The upper Delaware estuary, near the freshwater end member, was characterized by high-suspended matter concentrations that scavenged dissolved (210)Po and (210)Pb. Box models were applied using mass balance calculations to assess the nuclides residence times in each estuary. Only 60% of the dissolved (210)Po and 55% of the dissolved (210)Pb from the Delaware estuary were exported to coastal waters. A large fraction of soluble (210)Po and (210)Pb within the estuary was either reversibly adsorbed onto suspended particles, trapped in sediment accumulation zones (such as intertidal marshes), bioaccumulated into phytoplankton and discharged to the coastal ocean. The upper Chesapeake estuary was largely characterized by sub-oxic bottom waters that contained higher concentrations of dissolved (210)Po and (210)Pb, hypothesized to be subjected to redox cycling of manganese. The Delaware and Chesapeake estuary mean residence times for (210)Po differed significantly at 86 ± 7 and 126 ± 10 days respectively, while they were similar for (210)Pb (67 ± 6-55 ± 5 days). The difference in residence times corresponds to the greater extent of biogeochemical scavenging and regeneration processes within the upper Chesapeake. PMID:25239647

  11. Disequilibrium between [sup 226]Ra and supported [sup 210]Pb in a sediment core from a shallow Florida lake

    SciTech Connect

    Brenner, M.; Peplov, A.J.; Schelske, C.L. )

    1994-07-01

    [sup 210]Pb dating can be used to assign ages in lake sediment cores, calculate rates of sediment accumulation, and determine the timing of recent changes in lake-watershed ecosystems. We used low-background gamma counting to measure [sup 226]Ra and total [sup 210]Pb activity in a core from Lake Rowell, Florida. [sup 226]Ra activity was high and strongly variable throughout the core, even exceeding total [sup 210]Pb activity in recently deposited sediments. We traced one source of Ra-rich sediments to the only inflow, Alligator Creek, where stream-bottom deposits display disequilibrium between [sup 226]Ra and supported [sup 210]Pb. High and variable [sup 226]Ra activity in the Lake Rowell profile argues for direct estimates of in situ Ra in lake sediment cores from disturbed watersheds that have Ra-bearing bedrock. Isotopic disequilibrium between [sup 226]Ra and supported [sup 210]Pb makes it difficult to distinguish between supported and unsupported [sup 210]Pb activity throughout the Lake Rowell core and would require special assumptions and nonconventional dating models to establish age-depth relationships. 78 refs., 3 figs., 1 tab.

  12. 210Pb balance and implications for particle transport on the continental shelf, U.S. Middle Atlantic Bight

    USGS Publications Warehouse

    Bacon, M.P.; Belastock, Rebecca A.; Bothner, Michael H.

    1994-01-01

    Supply of 210Pb to the continental shelf off the northeastern United States is dominated by the deposition from the atmosphere, the rate of which is reliably known from previously published work. Excess 210Pb inventories in the shelf sediments show accumulations that are nearly in balance with the supply, even in areas of relict sands where it is believed that no net accumulation of sediment presently occurs. The 210Pb distributions in shelf and slope water indicate that the two-way fluid exchange at the shelf-slope front and the net transport in the alongshore flow make comparatively small contributions to the shelf 210Pb budget. The near balance between supply and decay of 210Pb on the shelf implies a limit to the particle export flux. It is concluded that the export of particulate organic carbon does not exceed 60 g m-2 y-1 (???25% of primary production) and is probably lower. The hypothesis is advanced that fine particulate matter introduced to the continental shelf is detained in its transit of the shelf because of bioturbational trapping in the sediment due to benthic animals. Distributions of 210Pb in suspended particulate matter and in the fine fraction of shelf sediments suggest that the average fine particle must undergo several cycles of deposition-bioturbation-resuspension-redeposition and requires a number of decades for its transit and ultimate export from the shelf. Thus, only the most refractory organic matter is likely to be exported. ?? 1994.

  13. Natural radionuclides (210)Po and (210)Pb in the Delaware and Chesapeake Estuaries: modeling scavenging rates and residence times.

    PubMed

    Marsan, D; Rigaud, S; Church, T

    2014-12-01

    During the spring and summer months of 2012, (210)Po and (210)Pb activity were measured in the dissolved and particulate phases from the Delaware and upper Chesapeake estuaries. The upper Delaware estuary, near the freshwater end member, was characterized by high-suspended matter concentrations that scavenged dissolved (210)Po and (210)Pb. Box models were applied using mass balance calculations to assess the nuclides residence times in each estuary. Only 60% of the dissolved (210)Po and 55% of the dissolved (210)Pb from the Delaware estuary were exported to coastal waters. A large fraction of soluble (210)Po and (210)Pb within the estuary was either reversibly adsorbed onto suspended particles, trapped in sediment accumulation zones (such as intertidal marshes), bioaccumulated into phytoplankton and discharged to the coastal ocean. The upper Chesapeake estuary was largely characterized by sub-oxic bottom waters that contained higher concentrations of dissolved (210)Po and (210)Pb, hypothesized to be subjected to redox cycling of manganese. The Delaware and Chesapeake estuary mean residence times for (210)Po differed significantly at 86 ± 7 and 126 ± 10 days respectively, while they were similar for (210)Pb (67 ± 6-55 ± 5 days). The difference in residence times corresponds to the greater extent of biogeochemical scavenging and regeneration processes within the upper Chesapeake.

  14. sup 210 Po and sup 210 Pb remobilization from lake sediments in relation to iron and manganese cycling

    SciTech Connect

    Benoit, G.; Hemond, H.F. )

    1990-08-01

    The behavior of {sup 210}Po and {sup 210}Pb was studied in the water column of an oligotrophic, dimictic lake. Direct uptake of the radionuclides by sediments was negligible compared to removal on particles, and {sup 210}Pb scavenging was 4 times that of {sup 210}Po. Both nuclides were found to be significantly remobilized from sediments into the stratified, anoxic water column. Releases seem to be linked to the cycling of the transition metals, iron and possibly manganese. The distribution of both iron and {sup 210}Pb in stratified, anoxic waters can be modeled as constant release and rapid horizontal mixing/dilution; vertical turbulent transport had a negligible effect on element distributions. Upon contact with oxygen, iron rapidly reprecipitates, forming a particulate maximum and rescavenging {sup 210}Pb. Unlike {sup 210}Pb, much {sup 210}Po is released from sediments before overlying water becomes completely anoxic, leading to unsupported {sup 210}Po. {sup 210}Po cycling in the stratified water column is more complex than that of {sup 210}Pb, and additional removal mechanism(s) may be active, including perhaps oxidation of soluble Po(II) to insoluble Po(IV).

  15. 137Cs activities and 135Cs/137Cs isotopic ratios from soils at Idaho National Laboratory: a case study for contaminant source attribution in the vicinity of nuclear facilities.

    PubMed

    Snow, Mathew S; Snyder, Darin C; Clark, Sue B; Kelley, Morgan; Delmore, James E

    2015-03-01

    Radiometric and mass spectrometric analyses of Cs contamination in the environment can reveal the location of Cs emission sources, release mechanisms, modes of transport, prediction of future contamination migration, and attribution of contamination to specific generator(s) and/or process(es). The Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) represents a complicated case study for demonstrating the current capabilities and limitations to environmental Cs analyses. (137)Cs distribution patterns, (135)Cs/(137)Cs isotope ratios, known Cs chemistry at this site, and historical records enable narrowing the list of possible emission sources and release events to a single source and event, with the SDA identified as the emission source and flood transport of material from within Pit 9 and Trench 48 as the primary release event. These data combined allow refining the possible number of waste generators from dozens to a single generator, with INL on-site research and reactor programs identified as the most likely waste generator. A discussion on the ultimate limitations to the information that (135)Cs/(137)Cs ratios alone can provide is presented and includes (1) uncertainties in the exact date of the fission event and (2) possibility of mixing between different Cs source terms (including nuclear weapons fallout and a source of interest). PMID:25633972

  16. 137Cs activities and 135Cs/137Cs isotopic ratios from soils at Idaho National Laboratory: a case study for contaminant source attribution in the vicinity of nuclear facilities.

    PubMed

    Snow, Mathew S; Snyder, Darin C; Clark, Sue B; Kelley, Morgan; Delmore, James E

    2015-03-01

    Radiometric and mass spectrometric analyses of Cs contamination in the environment can reveal the location of Cs emission sources, release mechanisms, modes of transport, prediction of future contamination migration, and attribution of contamination to specific generator(s) and/or process(es). The Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) represents a complicated case study for demonstrating the current capabilities and limitations to environmental Cs analyses. (137)Cs distribution patterns, (135)Cs/(137)Cs isotope ratios, known Cs chemistry at this site, and historical records enable narrowing the list of possible emission sources and release events to a single source and event, with the SDA identified as the emission source and flood transport of material from within Pit 9 and Trench 48 as the primary release event. These data combined allow refining the possible number of waste generators from dozens to a single generator, with INL on-site research and reactor programs identified as the most likely waste generator. A discussion on the ultimate limitations to the information that (135)Cs/(137)Cs ratios alone can provide is presented and includes (1) uncertainties in the exact date of the fission event and (2) possibility of mixing between different Cs source terms (including nuclear weapons fallout and a source of interest).

  17. Effects of landforms on the erosion rate in a small watershed by the (137)Cs tracing method.

    PubMed

    Li, Mian; Yao, Wenyi; Li, Zhanbin; Liu, Puling; Shen, Zhenzhou

    2010-05-01

    It's very important to analyze and evaluate quantitatively the effects of landforms on soil erosion for the prevention and treatment of soil loss in a small watershed. The objective of this study was to evaluate the effects of landform factors on erosion rate by the (137)Cs tracing method in a small watershed in the Purple Hilly Area of China. The erosion rates under different slope lengths, slope gradients and slope aspects were estimated in Xiangshuitan watershed in the Purple Hilly Area in Sichuan Basin by the (137)Cs tracing method. The results showed that the erosion rate decreased exponentially with downslope distance, and it increased with increasing slope gradient during the scope of 5 degrees -16 degrees. The slope aspect had great impact on the erosion rate, and the hillside on the sunny slope had larger erosion rate than that on the shady slope, particularly for the farmland.

  18. Effects of landforms on the erosion rate in a small watershed by the (137)Cs tracing method.

    PubMed

    Li, Mian; Yao, Wenyi; Li, Zhanbin; Liu, Puling; Shen, Zhenzhou

    2010-05-01

    It's very important to analyze and evaluate quantitatively the effects of landforms on soil erosion for the prevention and treatment of soil loss in a small watershed. The objective of this study was to evaluate the effects of landform factors on erosion rate by the (137)Cs tracing method in a small watershed in the Purple Hilly Area of China. The erosion rates under different slope lengths, slope gradients and slope aspects were estimated in Xiangshuitan watershed in the Purple Hilly Area in Sichuan Basin by the (137)Cs tracing method. The results showed that the erosion rate decreased exponentially with downslope distance, and it increased with increasing slope gradient during the scope of 5 degrees -16 degrees. The slope aspect had great impact on the erosion rate, and the hillside on the sunny slope had larger erosion rate than that on the shady slope, particularly for the farmland. PMID:20346551

  19. Measurement of airborne 131I, 134)Cs and 137Cs due to the Fukushima reactor incident in Milan (Italy).

    PubMed

    Clemenza, M; Fiorini, E; Previtali, E; Sala, E

    2012-12-01

    After the earthquake and the tsunami occurred in Japan on March 2011, four of the Fukushima reactors had released in air a large amount of radioactive isotopes that diffused all over the world. The presence of airborne (131)I, (134)Cs, and (137)Cs in air particulate due to this accident were detected and measured in the Low Radioactivity Laboratory operating in the Department of Environmental Sciences of the University of Milano-Bicocca. The sensitivity of the detecting apparatus is of 0.2 uBq/m(3) of air. Concentration and time distribution of these radiocontaminations ranging from a few to 400 uBq/m(3) for the (131)I and of a few tens of uBq/m(3) for the (137)Cs and (134)Cs.

  20. A preliminary study for the development of reference material using oyster for determination of (137)Cs, (90)Sr and plutonium isotopes.

    PubMed

    Lee, Sang-Han; Oh, Jung-Suk; Lee, Jong-Man; Lee, Kyung-Bum; Park, Tae-Soon; Lee, Min-Kie; Kim, Seung-Hwan; Choi, Jong-Ki

    2016-03-01

    A new reference material for the determination of (137)Cs, (90)Sr and Pu isotopes ((238)Pu and (239,240)Pu) is being developed using dried oyster matrix by Korea Research Institute of Standards and Science (KRISS). The oyster was collected from Tongyoung harbour, southern part of Korea and the artificial radionuclides ((137)Cs, (90)Sr, (238)Pu and (239,240)Pu) were spiked into the material. After pretreatment and processing, the material was tested for homogeneity and massic activities were determined by measuring (137)Cs, (90)Sr, (238)Pu and (239,240)Pu. The reference value and extended uncertainty for those isotopes will be reported later.

  1. Assessment of (90)sr and (137)cs penetration into reinforced concrete (extent of "deepening") under natural atmospheric conditions.

    PubMed

    Farfán, Eduardo B; Gaschak, Sergey P; Maksymenko, Andrey M; Donnelly, Elizabeth H; Bondarkov, Mikhail D; Jannik, G Tim; Marra, James C

    2011-09-01

    When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered, including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of (90)Sr and (137)Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40 and 40-50 mm. Both (90)Sr and (137)Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total (137)Cs inventory and 70% of the total (90)Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. Strontium-90 ((90)Sr) had penetrated markedly deeper into the reinforced concrete structures than (137)Cs.

  2. Comparison of {sup 241}Am, {sup 239,240}Pu, and {sup 137}Cs concentrations in soil around Rocky Flats

    SciTech Connect

    Hulse, S.E.; Ibrahim, S.A.; Whicker, F.W.; Chapman, P.L.

    1999-03-01

    Gamma spectroscopy measurements were used to estimate concentrations of {sup 241}Am and {sup 137}Cs in soil profiles to depths of 21 cm at on-site and off-site locations around the Rocky Flats Environmental Technology Site and at regional background locations east of the Front Range between Colorado`s borders with New Mexico and Wyoming. Concentrations of these radionuclides were compared with concentrations of {sup 239,240}Pu in the same samples. Concentrations of {sup 241}Am in soil from depths of 0 to 3 cm decreased in an easterly direction from more than 5.3 kBq kg{sup {minus}1} 5 to 7 km away at a rate that was nearly proportional to the inverse square of distance. Deposits of {sup 137}Cs were ubiquitous, averaging 0.12 kBq kg{sup {minus}1} in soil from depths of 0 to 3 cm, but were unevenly distributed around Rocky Flats and the regional background locations. Deviations from the uniform exponential rate at which soil concentrations of {sup 137}Cs typically decreased with depth, {minus}0.25 cm{sup {minus}1} at undisturbed sites, enabled the authors to determine that about 10% of their sampling sites had been disturbed by erosion, tillage, or other factors. The mean rate at which {sup 239,240}Pu decreased with depth was about the same, {minus}0.23 cm{sup {minus}1}, throughout the study area. Soil concentrations of {sup 241}Am decreased with depth at a similar mean rate of {minus}0.22 cm{sup {minus}1} at locations close to the 903 pad where measurements were robust. Ratios between {sup 241}Am or {sup 239,240}Pu and {sup 137}Cs proved more useful for delineating the extent and pattern of contamination from Rocky Flats than did activity concentrations in soil.

  3. Assessment of (90)sr and (137)cs penetration into reinforced concrete (extent of "deepening") under natural atmospheric conditions.

    PubMed

    Farfán, Eduardo B; Gaschak, Sergey P; Maksymenko, Andrey M; Donnelly, Elizabeth H; Bondarkov, Mikhail D; Jannik, G Tim; Marra, James C

    2011-09-01

    When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered, including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of (90)Sr and (137)Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40 and 40-50 mm. Both (90)Sr and (137)Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total (137)Cs inventory and 70% of the total (90)Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. Strontium-90 ((90)Sr) had penetrated markedly deeper into the reinforced concrete structures than (137)Cs. PMID:21799347

  4. A pilot study on the transfer of 137Cs and 90Sr to horse milk and meat.

    PubMed

    Semioshkina, N; Voigt, G; Fesenko, S; Savinkov, A; Mukusheva, M

    2006-01-01

    The radiological assessment of the impact of nuclear weapon's testing on the Semipalatinsk Test Site (STS) on the local population requires comprehensive site-specific information on radionuclide behaviour in the environment. However, information on radionuclide behaviour in the conditions of the STS is rather sparse and, in particular, there are no data in the literature on parameters of radionuclide transfer from feed to horse products proofed to be important contributors to the internal dose to the local population. The transfer of 137Cs and 90Sr to horse milk and meat was studied under laboratory and field conditions: in controlled experiment with three lactating horses maintained in the Kazakh Agricultural Research Institute, and in field measurements of horse products taken from horses grazing at the Semipalatinsk Test Site. The equilibrium transfer factors from feed to horse milk and meat were estimated to be 0.012 dl(-1) and 0.035 dkg(-1) for (137)Cs and 0.0022 dl(-1) and 0.003 dkg(-1) for (90)Sr, respectively. The biological half-lives were approximated by a sum of two exponentials amounting to 3 (85%) and 15 (15%) days for 137Cs and 3.5 (70%) and 100 (30%) days for 90Sr. The highest 137Cs transfer has been found to be to spleen, followed by lung, heart, muscles, kidneys, intestine, and finally skin and bones. For90Sr, the maximum activity concentration was observed in bones; contamination of other tissues is rather uniform except for liver and intestine with a factor of about 2 higher than muscles.

  5. Measurement of fallout radionuclides, (239)(,240)Pu and (137)Cs, in soil and creek sediment: Sydney Basin, Australia.

    PubMed

    Smith, B S; Child, D P; Fierro, D; Harrison, J J; Heijnis, H; Hotchkis, M A C; Johansen, M P; Marx, S; Payne, T E; Zawadzki, A

    2016-01-01

    Soil and sediment samples from the Sydney basin were measured to ascertain fallout radionuclide activity concentrations and atom ratios. Caesium-137 ((137)Cs) was measured using gamma spectroscopy, and plutonium isotopes ((239)Pu and (240)Pu) were quantified using accelerator mass spectrometry (AMS). Fallout radionuclide activity concentrations were variable ranging from 0.6 to 26.1 Bq/kg for (137)Cs and 0.02-0.52 Bq/kg for (239+240)Pu. Radionuclides in creek sediment samples were an order of magnitude lower than in soils. (137)Cs and (239+240)Pu activity concentration in soils were well correlated (r(2) = 0.80) although some deviation was observed in samples collected at higher elevations. Soil ratios of (137)Cs/(239+240)Pu (decay corrected to 1/1/2014) ranged from 11.5 to 52.1 (average = 37.0 ± 12.4) and showed more variability than previous studies. (240)Pu/(239)Pu atom ratios ranged from 0.117 to 0.165 with an average of 0.146 (±0.013) and an error weighted mean of 0.138 (±0.001). These ratios are lower than a previously reported ratio for Sydney, and lower than the global average. However, these ratios are similar to those reported for other sites within Australia that are located away from former weapons testing sites and indicate that atom ratio measurements from other parts of the world are unlikely to be applicable to the Australian context. PMID:26344369

  6. Comparison of 241Am, (239,240)Pu and 137Cs concentrations in soil around rocky flats.

    PubMed

    Hulse, S E; Ibrahim, S A; Whicker, F W; Chapman, P L

    1999-03-01

    Gamma spectroscopy measurements were used to estimate concentrations of 241Am and 137Cs in soil profiles to depths of 21 cm at on-site and off-site locations around the Rocky Flats Environmental Technology Site and at regional background locations east of the Front Range between Colorado's borders with New Mexico and Wyoming. Concentrations of these radionuclides were compared with concentrations of (239,240)Pu in the same samples. Concentrations of 241Am in soil from depths of 0 to 3 cm decreased in an easterly direction from more than 5.3 kBq kg(-1) near the 903 pad to background levels of 1.3 Bq kg(-1) 5 to 7 km away at a rate that was nearly proportional to the inverse square of distance. Deposits of 137Cs were ubiquitous, averaging 0.12 kBq kg(-1) in soil from depths of 0 to 3 cm, but were unevenly distributed around Rocky Flats and the regional background locations. Deviations from the uniform exponential rate at which soil concentrations of 137Cs typically decreased with depth, -0.25 cm(-1) at undisturbed sites, enabled us to determine that about 10% of our sampling sites had been disturbed by erosion, tillage, or other factors. The mean rate at which (239,240)Pu decreased with depth was about the same, -0.23 cm(-1), throughout the study area. Soil concentrations of 241Am decreased with depth at a similar mean rate of -0.22 cm(-1) at locations close to the 903 pad where measurements were robust. Ratios between 241Am or (239,240)Pu and 137Cs proved more useful for delineating the extent and pattern of contamination from Rocky Flats than did activity concentrations in soil. PMID:10025653

  7. The use of 137Cs to establish longer-term soil erosion rates on footpaths in the UK.

    PubMed

    Rodway-Dyer, S J; Walling, D E

    2010-10-01

    There is increasing awareness of the damage caused to valuable and often unique sensitive habitats by people pressure as degradation causes a loss of plant species, disturbance to wildlife, on-site and off-site impacts of soil movement and loss, and visual destruction of pristine environments. This research developed a new perspective on the problem of recreational induced environmental degradation by assessing the physical aspects of soil erosion using the fallout radionuclide caesium-137 ((137)Cs). Temporal sampling problems have not successfully been overcome by traditional research methods monitoring footpath erosion and, to date, the (137)Cs technique has not been used to estimate longer-term soil erosion in regard to sensitive recreational habitats. The research was based on-sites within Dartmoor National Park (DNP) and the South West Coast Path (SWCP) in south-west England. (137)Cs inventories were reduced on the paths relative to the reference inventory (control), indicating loss of soil from the path areas. The Profile Distribution Model estimated longer-term erosion rates (ca. 40 years) based on the (137)Cs data and showed that the combined mean soil loss for all the sites on 'paths' was 1.41 kg m(-2) yr(-1) whereas the combined 'off path' soil loss was 0.79 kg m(-2) yr(-1), where natural (non-recreational) soil redistribution processes occur. Recreational pressure was shown to increase erosion in the long-term, as greater soil erosion occurred on the paths, especially where there was higher visitor pressure.

  8. The use of 137Cs to establish longer-term soil erosion rates on footpaths in the UK.

    PubMed

    Rodway-Dyer, S J; Walling, D E

    2010-10-01

    There is increasing awareness of the damage caused to valuable and often unique sensitive habitats by people pressure as degradation causes a loss of plant species, disturbance to wildlife, on-site and off-site impacts of soil movement and loss, and visual destruction of pristine environments. This research developed a new perspective on the problem of recreational induced environmental degradation by assessing the physical aspects of soil erosion using the fallout radionuclide caesium-137 ((137)Cs). Temporal sampling problems have not successfully been overcome by traditional research methods monitoring footpath erosion and, to date, the (137)Cs technique has not been used to estimate longer-term soil erosion in regard to sensitive recreational habitats. The research was based on-sites within Dartmoor National Park (DNP) and the South West Coast Path (SWCP) in south-west England. (137)Cs inventories were reduced on the paths relative to the reference inventory (control), indicating loss of soil from the path areas. The Profile Distribution Model estimated longer-term erosion rates (ca. 40 years) based on the (137)Cs data and showed that the combined mean soil loss for all the sites on 'paths' was 1.41 kg m(-2) yr(-1) whereas the combined 'off path' soil loss was 0.79 kg m(-2) yr(-1), where natural (non-recreational) soil redistribution processes occur. Recreational pressure was shown to increase erosion in the long-term, as greater soil erosion occurred on the paths, especially where there was higher visitor pressure. PMID:20627401

  9. Transport of 137Cs and 239,240Pu with ice-rafted debris in the Arctic Ocean

    USGS Publications Warehouse

    Landa, E.R.; Reimnitz, E.; Beals, D.M.; Pochkowski, J.M.; Winn, W.G.; Rigor, I.

    1998-01-01

    Ice rafting is the dominant mechanism responsible for the transport of fine-grained sediments from coastal zones to the deep Arctic Basin. Therefore, the drift of ice-rafted debris (IRD) could be a significant transport mechanism from the shelf to the deep basin for radionuclides originating from nuclear fuel cycle activities and released to coastal Arctic regions of the former Soviet Union. In this study, 28 samples of IRD collected from the Arctic ice pack during expeditions in 1989-95 were analyzed for 137Cs by gamma spectrometry and for 239Pu and 240Pu by thermal ionization mass spectrometry. 137Cs concentrations in the IRD ranged from less than 0.2 to 78 Bq??kg-1 (dry weight basis). The two samples with the highest 137Cs concentrations were collected in the vicinity of Franz Josef Land, and their backward trajectories suggest origins in the Kara Sea. Among the lowest 137Cs values are seven measured on sediments entrained on the North American shelf in 1989 and 1995, and sampled on the shelf less than six months later. Concentrations of 239Pu + 240Pu ranged from about 0.02 to 1.8 Bq??kg-1. The two highest values came from samples collected in the central Canada Basin and near Spitsbergen; calculated backward trajectories suggest at least 14 years of circulation in the Canada Basin in the former case, and an origin near Severnaya Zemlya (at the Kara Sea/Laptev Sea boundary) in the latter case. While most of the IRD samples showed 240Pu/239Pu ratios near the mean global fallout value of 0.185, five of the samples had lower ratios, in the 0.119 to 0.166 range, indicative of mixtures of Pu from fallout and from the reprocessing of weapons-grade Pu. The backward trajectories of these five samples suggest origins in the Kara Sea or near Severnaya Zemlya.

  10. Measurement of fallout radionuclides, (239)(,240)Pu and (137)Cs, in soil and creek sediment: Sydney Basin, Australia.

    PubMed

    Smith, B S; Child, D P; Fierro, D; Harrison, J J; Heijnis, H; Hotchkis, M A C; Johansen, M P; Marx, S; Payne, T E; Zawadzki, A

    2016-01-01

    Soil and sediment samples from the Sydney basin were measured to ascertain fallout radionuclide activity concentrations and atom ratios. Caesium-137 ((137)Cs) was measured using gamma spectroscopy, and plutonium isotopes ((239)Pu and (240)Pu) were quantified using accelerator mass spectrometry (AMS). Fallout radionuclide activity concentrations were variable ranging from 0.6 to 26.1 Bq/kg for (137)Cs and 0.02-0.52 Bq/kg for (239+240)Pu. Radionuclides in creek sediment samples were an order of magnitude lower than in soils. (137)Cs and (239+240)Pu activity concentration in soils were well correlated (r(2) = 0.80) although some deviation was observed in samples collected at higher elevations. Soil ratios of (137)Cs/(239+240)Pu (decay corrected to 1/1/2014) ranged from 11.5 to 52.1 (average = 37.0 ± 12.4) and showed more variability than previous studies. (240)Pu/(239)Pu atom ratios ranged from 0.117 to 0.165 with an average of 0.146 (±0.013) and an error weighted mean of 0.138 (±0.001). These ratios are lower than a previously reported ratio for Sydney, and lower than the global average. However, these ratios are similar to those reported for other sites within Australia that are located away from former weapons testing sites and indicate that atom ratio measurements from other parts of the world are unlikely to be applicable to the Australian context.

  11. ASSESSMENT OF 90SR AND 137CS PENETRATION INTO REINFORCED CONCRETE (EXTENT OF 'DEEPENING') UNDER NATURAL ATMOSPHERIC CONDITIONS

    SciTech Connect

    Farfan, E.; Jannik, T.

    2011-10-01

    When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures, and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of {sup 90}Sr and {sup 137}Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40, and 40-50 mm. Both {sup 90}Sr and {sup 137}Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total {sup 137}Cs inventory and 70% of the total {sup 90}Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. {sup 90}Sr had penetrated markedly deeper into the reinforced concrete structures than {sup 137}Cs.

  12. Transfer factor of (90)Sr and (137)Cs to lettuce and winter wheat at different growth stage applications.

    PubMed

    Al Attar, Lina; Al-Oudat, Mohammad; Safia, Bassam; Ghani, Basem Abdul

    2015-12-01

    The effect of clay soil contamination time on the transfer factors (Fvs) of (137)Cs and (90)Sr was investigated in four different growth stages of winter wheat and lettuce crops. The experiment was performed in an open field using lysimeters. The Fvs were the ratio of the activity concentrations of the radionuclides in crops to those in soil, both as dry weight (Bq kg(-1)). Significant difference of log-Fvs was evaluated using one-way Analysis of Variance (ANOVA). Basically, Fvs of (90)Sr were higher than those of (137)Cs, despite of the application stage or crop' variety. Higher Fvs for both radionuclides were observed for lettuce in comparison to winter wheat. Fvs of (90)Sr showed comparable trends for both crops with enhanced Fvs obtained when contamination occurred in early stages, i.e. 1.20 for lettuce and 0.88 and 0.02 for winter wheat, straw and grains, respectively. Despite the fluctuation noted in the pattern of Fvs for (137)Cs, soil contaminated at the second stage gave the highest Fvs for lettuce and grains, with geometric means of 0.21 and 0.01, respectively. However, wheat-straw showed remarkable increase in Fv for the latest contamination (ripening stage), about 0.06. It could be concluded that soil contamination at early growth stages would represent high radiological risk for the scenarios studied with an exception to (137)Cs in winter wheat-straw which reflected greater hazard at the latest application.

  13. Spatial variation in the (137)Cs inventory in soils in a mixed deciduous forest in Fukushima, Japan.

    PubMed

    Takada, Momo; Yamada, Toshihiro; Takahara, Teruhiko; Okuda, Toshinori

    2016-09-01

    The spatial variation of the radiocesium inventory in forest soil was studied c.a. 44 km northwest of the Fukushima Daiichi Nuclear Power Plant, Japan. This study focuses on the effects of canopy interception and downward transfer from the forest canopy to the forest floor via stemflow and throughfall. We established a study plot (400 m(2)) in the canopy layer of a secondary mixed deciduous forest dominated by Japanese oak (Quercus crispula) and Japanese fir (Abies firma), in August and November 2014. Soil was sampled from 0 to 5 cm depth and (137)Cs was measured under the canopy using a 2-m grid and also at the tree trunk bases. We divided the study plot into the five different types of subplot according to the canopy projection areas and the tree species for the analysis. The geometric mean and coefficient of variation of the (137)Cs inventory were 202 kBq m(-2) and 0.11 (0.52 in the arithmetic coefficient of variation), respectively. Within the forest, the variation in the (137)Cs inventory under trees was larger than in crown gap areas. The large spatial variation may be attributed to canopy interception of the initial deposition and downward transfer of radiocesium via stemflow and throughfall.

  14. Distribution and source of (129)I, (239)(,240)Pu, (137)Cs in the environment of Lithuania.

    PubMed

    Ežerinskis, Ž; Hou, X L; Druteikienė, R; Puzas, A; Šapolaitė, J; Gvozdaitė, R; Gudelis, A; Buivydas, Š; Remeikis, V

    2016-01-01

    Fifty five soil samples collected in the Lithuania teritory in 2011 and 2012 were analyzed for (129)I, (137)Cs and Pu isotopes in order to investigate the level and distribution of artificial radioactivity in Lithuania. The activity and atomic ratio of (238)Pu/((239,24)0)Pu, (129)I/(127)I and (131)I/(137)Cs were used to identify the origin of these radionuclides. The (238)Pu/(239+240)Pu and (240)Pu/(239)Pu ratios in the soil samples analyzed varied in the range of 0.02-0.18 and 0.18-0.24, respectively, suggesting the global fallout as the major source of Pu in Lithuania. The values of 10(-9) to 10(-6) for (129)I/(127)I atomic ratio revealed that the source of (129)I in Lithuania is global fallout in most cases though several sampling sites shows a possible impact of reprocessing releases. Estimated (129)I/(131)I ratio in soil samples from the southern part of Lithuania shows negligible input of the Chernobyl fallout. No correlation of the (137)Cs and Pu isotopes with (129)I was observed, indicating their different sources terms. Results demonstrate uneven distribution of these radionuclides in the Lithuanian territory and several sources of contamination i.e. Chernobyl accident, reprocessing releases and global fallout.

  15. Effect of Potassium on Uptake of 137Cs in Food Crops Grown on Coral Soils: Annual Crops at Bikini Atoll

    SciTech Connect

    Stone, E R; Robinson, W

    2002-02-01

    In 1954 a radioactive plume from the thermonuclear device code named BRAVO contaminated the principal residential islands, Eneu and Bikini, of Bikini Atoll (11{sup o} 36 minutes N; 165{sup o} 22 minutes E), now part of the Republic of the Marshall Islands. The resulting soil radioactivity diminished greatly over the three decades before the studies discussed below began. By that time the shorter-lived isotopes had all but disappeared, but strontium-90 ({sup 90}Sr), and cesium-137, ({sup 137}Cs) were reduced by only one half-life. Minute amounts of the long-lived isotopes, plutonium-239+240 ({sup 239+240}Pu) and americium-241 ({sup 241}Am), were present in soil, but were found to be inconsequential in the food chain of humans and land animals. Rather, extensive studies demonstrated that the major concern for human health was {sup 137}Cs in the terrestrial food chain (Robison et al., 1983; Robison et al., 1997). The following papers document results from several studies between 1986 and 1997 aimed at minimizing the {sup 137}Cs content of annual food crops. The existing literature on radiocesium in soils and plant uptake is largely a consequence of two events: the worldwide fallout of 1952-58, and the fallout from Chernobyl. The resulting studies have, for the most part, dealt either with soils containing some amount of silicate clays and often with appreciable K, or with the short-term development of plants in nutrient cultures.

  16. Suitability of 239+240Pu and 137Cs as tracers for soil erosion assessment in Swiss mountain grasslands

    NASA Astrophysics Data System (ADS)

    Alewell, Christine; Meusburger, Katrin; Juretzko, Gregor; Mabit, Lionel; Ketterer, Michael E.

    2014-05-01

    We compare the suitability of the anthropogenic FRNs, 137Cs and 239+240Pu as soil erosion tracers in two alpine valleys of Switzerland (Ursern Valley, Canton Uri, Central Swiss Alps and Val Piora, Ticino, Southern Alps). We sampled reference and potentially erosive sites in transects along both valleys. 137Cs measurements of soil samples were done with a Li-drifted Germanium detector and 239+240Pu with ICP-MS. Our data indicates a heterogeneous deposition of the 137Cs, since most of the fallout origins from the Chernobyl April/May 1986 accident, when large parts of the European Alps were still snow-covered. In contrast, 239+240Pu fallout originated mainly from 1950's-1960's atmospheric nuclear weapons tests, resulting in a more homogenous distribution and thus seems to be a more suitable tracer in mountainous grasslands. Soil erosion assessment using 239+240Pu as a tracer pointed to a huge dynamic and high heterogeneity of erosive processes (between sedimentation of 0.9 to 6.4 t ha1yr1 and erosion of 2.3 to 14.1 t ha1yr1 in the Ursern Valley and sedimentation of 0.7 to 77 t ha1yr1 and erosion of 1 to 5.3 t ha1yr1at Val Piora). Our study represents a novel, successful application of 239+240Pu as a tracer of soil erosion in a mountain environment.

  17. Spatial variation in the (137)Cs inventory in soils in a mixed deciduous forest in Fukushima, Japan.

    PubMed

    Takada, Momo; Yamada, Toshihiro; Takahara, Teruhiko; Okuda, Toshinori

    2016-09-01

    The spatial variation of the radiocesium inventory in forest soil was studied c.a. 44 km northwest of the Fukushima Daiichi Nuclear Power Plant, Japan. This study focuses on the effects of canopy interception and downward transfer from the forest canopy to the forest floor via stemflow and throughfall. We established a study plot (400 m(2)) in the canopy layer of a secondary mixed deciduous forest dominated by Japanese oak (Quercus crispula) and Japanese fir (Abies firma), in August and November 2014. Soil was sampled from 0 to 5 cm depth and (137)Cs was measured under the canopy using a 2-m grid and also at the tree trunk bases. We divided the study plot into the five different types of subplot according to the canopy projection areas and the tree species for the analysis. The geometric mean and coefficient of variation of the (137)Cs inventory were 202 kBq m(-2) and 0.11 (0.52 in the arithmetic coefficient of variation), respectively. Within the forest, the variation in the (137)Cs inventory under trees was larger than in crown gap areas. The large spatial variation may be attributed to canopy interception of the initial deposition and downward transfer of radiocesium via stemflow and throughfall. PMID:27173786

  18. Extrapolating soil redistribution rates estimated from 137Cs to catchment scale in a complex agroforestry landscape using GIS

    NASA Astrophysics Data System (ADS)

    Gaspar, Leticia; López-Vicente, Manuel; Palazón, Leticia; Quijano, Laura; Navas, Ana

    2015-04-01

    The use of fallout radionuclides, particularly 137Cs, in soil erosion investigations has been successfully used over a range of different landscapes. This technique provides mean annual values of spatially distributed soil erosion and deposition rates for the last 40-50 years. However, upscaling the data provided by fallout radionuclides to catchment level is required to understand soil redistribution processes, to support catchment management strategies, and to assess the main soil erosion factors like vegetation cover or topography. In recent years, extrapolating field scale soil erosion rates estimated from 137Cs data to catchment scale has been addressed using geostatistical interpolation and Geographical Information Systems (GIS). This study aims to assess soil redistribution in an agroforestry catchment characterized by abrupt topography and an intricate mosaic of land uses using 137Cs data and GIS. A new methodological approach using GIS is presented as an alternative of interpolation tools to extrapolating soil redistribution rates in complex landscapes. This approach divides the catchment into Homogeneous Physiographic Units (HPUs) based on unique land use, hydrological network and slope value. A total of 54 HPUs presenting specific land use, strahler order and slope combinations, were identified within the study area (2.5 km2) located in the north of Spain. Using 58 soil erosion and deposition rates estimated from 137Cs data, we were able to characterize the predominant redistribution processes in 16 HPUs, which represent the 78% of the study area surface. Erosion processes predominated in 6 HPUs (23%) which correspond with cultivated units in which slope and strahler order is moderate or high, and with scrubland units with high slope. Deposition was predominant in 3 HPUs (6%), mainly in riparian areas, and to a lesser extent in forest and scrubland units with low slope and low and moderate strahler order. Redistribution processes, both erosion and

  19. Time-dependent transfer of 137Cs, 85Sr and 65Zn to earthworms in highly contaminated soils.

    PubMed

    Keum, Dong-Kwon; Jun, In; Lim, Kwang-Muk; Choi, Yong-Ho; Howard, Brenda J

    2013-12-01

    The transfer characteristics of (137)Cs, (85)Sr and (65)Zn to earthworms (Eisenia andrei) in soils with different amounts of the radionuclides have been investigated. The time-dependent whole-body concentration ratios (CR) were derived for worms in artificially contaminated soils with three different activity concentrations. Two parameters of a first order kinetic model, the equilibrium concentration ratio (CR(eq)) and the effective loss rate constant (k), were estimated by a comparison of experimental CR results with model predictions. The estimated CR(eq) (Bq/kg fresh worm per Bq/kg dry soil) ranged from 3.9 × 10(-4) to 4.1 × 10(-3) for (137)Cs, 1.39 × 10(-3) to 2.94 × 10(-2) for (85)Sr, and 1.39 × 10(-3) to 5.0 × 10(-2) for (65)Zn, and consistently decreased with increasing soil activity concentration but the trend was not statistically significant. The CR(eq) for (137)Cs was one to two orders of magnitude lower than previously reported CR(wo-soil) values (based on field data with much less contaminated soil), that for (85)Sr was comparable with other reported values and for (65)Zn was less two to three orders of magnitude lower than CR(wo-soil) values for stable zinc. The estimated k (d(-1)) values ranged from 9 × 10(-2) to 1.4 × 10(-1) for (137)Cs, 7 × 10(-2) to 2 × 10(-1) for (85)Sr, and 6 × 10(-2) to 1.8 × 10(-1) for (65)Zn, and did not show a relationship with soil activity concentration. The effect of CR(eq) on the total dose rate was insignificant for (137)Cs or (65)Zn because external dose rates to the soil dwelling earthworms due to these radionuclides were much greater than the internal dose rate. In contrast, the total dose from (90)Sr was determined by the internal dose rate and therefore proportional to the CR(eq). PMID:22948029

  20. 210Pb and 210Po concentrations in Italian cigarettes and effective dose evaluation.

    PubMed

    Taroni, Mattia; Zagà, Vincenzo; Bartolomei, Paolo; Gattavecchia, Enrico; Pacifici, Roberta; Zuccaro, Piergiorgio; Esposito, Massimo

    2014-09-01

    It has been known for a long time that cigarette tobacco contains naturally occurring radioactive nuclides such as 210Pb and 210Po. In this study, the concentrations of 210Pb and 210Po in the 10 most widely sold cigarette brands in Italy during the year 2010 were measured, and the effective dose to smokers has been calculated. The results of this study show that 210Pb concentration ranged from 11.6 to 20.0 mBq cig-1 with an arithmetic mean of 14.6 mBq cig-1, while the activity concentration of 210Po ranged from 13.1 to 19.0 mBq cig-1 with an arithmetic mean of 15.7 mBq cig-1, thus confirming previous results and showing that the radioactivity concentration was not reduced in the last few years. The annual effective dose for a typical smoker consuming 20 cigarettes per day ranged from an average of 55 μSv y-1 to about 81 μSv y-1. It is finally put in evidence the need to improve the knowledge about crucial data needed for accurate dose assessment deriving from the inhalation of both radioisotopes contained in the cigarettes, namely the dose conversion coefficients, which strongly depend on several parameters such as the inhalation speed through the mouth, the real fraction of radionuclide transferred from cigarette to mainstream smoke, the lung absorption behavior of the radioisotopes inhaled with mainstream smoke, and the AMAD of particles inhaled by smokers.

  1. 210Pb and 210Po concentrations in Italian cigarettes and effective dose evaluation.

    PubMed

    Taroni, Mattia; Zagà, Vincenzo; Bartolomei, Paolo; Gattavecchia, Enrico; Pacifici, Roberta; Zuccaro, Piergiorgio; Esposito, Massimo

    2014-09-01

    It has been known for a long time that cigarette tobacco contains naturally occurring radioactive nuclides such as 210Pb and 210Po. In this study, the concentrations of 210Pb and 210Po in the 10 most widely sold cigarette brands in Italy during the year 2010 were measured, and the effective dose to smokers has been calculated. The results of this study show that 210Pb concentration ranged from 11.6 to 20.0 mBq cig-1 with an arithmetic mean of 14.6 mBq cig-1, while the activity concentration of 210Po ranged from 13.1 to 19.0 mBq cig-1 with an arithmetic mean of 15.7 mBq cig-1, thus confirming previous results and showing that the radioactivity concentration was not reduced in the last few years. The annual effective dose for a typical smoker consuming 20 cigarettes per day ranged from an average of 55 μSv y-1 to about 81 μSv y-1. It is finally put in evidence the need to improve the knowledge about crucial data needed for accurate dose assessment deriving from the inhalation of both radioisotopes contained in the cigarettes, namely the dose conversion coefficients, which strongly depend on several parameters such as the inhalation speed through the mouth, the real fraction of radionuclide transferred from cigarette to mainstream smoke, the lung absorption behavior of the radioisotopes inhaled with mainstream smoke, and the AMAD of particles inhaled by smokers. PMID:25068956

  2. Comparisons of 210Pb and pollen methods for determining rates of estuarine sediment accumulation

    USGS Publications Warehouse

    Brush, G.S.; Martin, E.A.; DeFries, R.S.; Rice, C.A.

    1982-01-01

    Comparisons of sedimentation rates obtained by 210Pb and pollen analyses of 1-m cores collected throughout the Potomac Estuary show good agreement in the majority of cores that can be analyzed by both methods. Most of the discrepancy between the methods can be explained by the analytical precision of the 210Pb method and by the exactness with which time horizons can be identified and dated for the pollen method. X-radiographs of the cores and the distinctness of the pollen horizons preclude significant displacement by reworking and/or mixing of sediments. Differences between the methods are greatest where uncertainties exist in assigning a rate by one or both methods (i.e., 210Pb trends and/or "possible" horizon assignments). Both methods show the same relative rates, with greater sediment accumulation more common in the upper and middle estuary and less toward the mouth. The results indicate that geochronologic studies of estuarine sediments should be preceded by careful observation of sedimentary structures, preferably by X-radiography, to evaluate the extent of mixing of the sediments. Time horizons, whether paleontologic or isotopic, are generally blurred where mixing has occurred, precluding precise identification. Whenever possible, two methods should be used for dating sediments because a rate, albeit erroneous, can be obtained isotopically in sediments that are mixed; accurate sedimentation rates are also difficult to determine where the time boundary is a zone rather than a horizon, where the historical record does not provide a precise date for the pollen horizon, or where scouring has removed some of the sediment above a dated pollen horizon. ?? 1982.

  3. 210-Pb Study of Fjord Sedimentation Rates in the South Shetland Islands and Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Kimball, B. L.; Nittrouer, C. A.; Landowski, C. M.; Koppes, M.; Hallet, B.

    2007-12-01

    As part of a study concerning the factors controlling rates of glacial erosion and sedimentation across climatic regimes, sixteen kasten cores were collected from ten fjords in the South Shetland Islands and Antarctic Peninsula in April and May, 2007 from the R/VIB Nathaniel B. Palmer. They were sampled for 210Pb measurements of accumulation rates and associated sedimentological observations (x-radiography, sedimentology). The cores were collected from basins within a few kilometers of the calving front at the respective glacier, where sediment accumulation was observed in 3.5 kHz sub-bottom profiles. Core lengths ranged from 34-289 cm; in 7 of the 16 core locations, multiple deployments were required to retrieve even a short sediment core due to the hardness of the bed. For most of the cores (10 of 16) sandy mud has accumulated steadily at rates ranging from 1 to 10 mm/y over the past century, as tightly defined by clear linear trends of 10 to 15 log 210Pb values versus depth, with r2 ranging from 0.75-0.98. The rates of accumulation appear to be independent of distance from the calving front, and most likely reflect variability in glacial-marine sediment delivery to, and basin morphology of, individual fjords. Several cores show evidence of variable sedimentation with pulses of sand emplacement. Three cores contained a surficial layer >50 cm thick of uniform 210Pb activity, indicating recent, rapid deposition of a large turbidity current or mass flow. The consistency of many of the 210Pb profiles implies that, over the past century, the glacial-marine processes that supplied, transported and deposited sediment in these sub-polar and polar fjords have not varied markedly. This contrasts with other glacial-marine systems in warmer regions such SE Alaska, where sedimentation in the fjords from calving temperate glaciers tends to vary significantly, and where the accumulation tends to slow as the calving front recedes rapidly from the core location. The rates of

  4. [The change in efficiency of protective measures for reduction of 137Cs accumulation by agricultural plants in various periods after the Chernobyl accident].

    PubMed

    Panov, A V; Aleksakhin, R M; Muzalevskaia, A A

    2011-01-01

    Dynamics of 137Cs transfer factors to plants and the effects of protective measures on this radionuclide accumulation in the agricultural production is estimated on the example of the south-western regions of Bryansk District. Three periods in decreasing the 137Cs content in plants during 20 years after the Chernobyl accident are identified. The contribution of radionuclide decay, natural biogeochemical processes and protective measures aimed at reduction of the 137Cs accumulation in agricultural plants during various periods after radioactive fallout is shown. Maximum permissible levels of 137Cs contamination of cultivated lands, where crop products meeting current standards may be obtained, at different scopes of protective measures on radioactive-contaminated territories are forecasted. Periods after radioactive fallout, when crop and forage products meeting radiological standards are obtained, are assessed. PMID:21520624

  5. Time-dependency of the 137Cs contamination of wild boar from a region in Southern Germany in the years 1998 to 2008.

    PubMed

    Semizhon, Tatiana; Putyrskaya, Victoria; Zibold, Gregor; Klemt, Eckehard

    2009-11-01

    Following the Chernobyl accident, (137)Cs contamination levels of wild boar in some districts of Southern Germany are still exceeding thousands of Bq kg(-1). While the long term (137)Cs concentration in forest plants, mushrooms, and roe deer meat has decreased significantly, for wild boar it has remained constant during the last decade. Between 1998 and 2008, we analysed the muscle meat of 656 wild boars shot in the district ("Landkreis") Ravensburg. The (137)Cs activity concentration showed considerable variability from less than 5 up to 8266 Bq kg(-1) and it followed a seasonal pattern, which is attributed to changes in dietary habits, fodder availability, meteorological conditions and specific behaviour of (137)Cs in wild boar organism. T(ag) values for wild boars from the district Ravensburg varied from 0.008 to 0.062 m(2)kg(-1) during 2000-2008.

  6. [The change in efficiency of protective measures for reduction of 137Cs accumulation by agricultural plants in various periods after the Chernobyl accident].

    PubMed

    Panov, A V; Aleksakhin, R M; Muzalevskaia, A A

    2011-01-01

    Dynamics of 137Cs transfer factors to plants and the effects of protective measures on this radionuclide accumulation in the agricultural production is estimated on the example of the south-western regions of Bryansk District. Three periods in decreasing the 137Cs content in plants during 20 years after the Chernobyl accident are identified. The contribution of radionuclide decay, natural biogeochemical processes and protective measures aimed at reduction of the 137Cs accumulation in agricultural plants during various periods after radioactive fallout is shown. Maximum permissible levels of 137Cs contamination of cultivated lands, where crop products meeting current standards may be obtained, at different scopes of protective measures on radioactive-contaminated territories are forecasted. Periods after radioactive fallout, when crop and forage products meeting radiological standards are obtained, are assessed.

  7. Analysis of mutant quantity and quality in human-hamster hybrid AL and AL-179 cells exposed to 137Cs-gamma or HZE-Fe ions

    NASA Technical Reports Server (NTRS)

    Waldren, C.; Vannais, D.; Drabek, R.; Gustafson, D.; Kraemer, S.; Lenarczyk, M.; Kronenberg, A.; Hei, T.; Ueno, A.; Chatterjee, A. (Principal Investigator)

    1998-01-01

    We measured the number of mutants and the kinds of mutations induced by 137Cs-gamma and by HZE-Fe (56Fe [600 MeV/amu, LET = 190 KeV/micrometer) in standard AL human hamster hybrid cells and in a new variant hybrid, AL-179. We found that HZE-Fe was more mutagenic than 137Cs-gamma per unit dose (about 1.6 fold), but was slightly less mutagenic per mean lethal dose, DO, at both the S1 and hprt- loci of AL cells. On the other hand, HZE-Fe induced about nine fold more complex S1- mutants than 137Cs-gamma rays, 28% vs 3%. 137Cs-gamma rays induced about twice as many S1- mutants and hprt-mutants in AL-179 as in AL cells, and about nine times more of the former were complex, and potentially unstable kinds of mutations.

  8. Linking spatial patterns of soil redistribution traced with 137Cs and soil nutrients in a Mediterranean mountain agroecosystem (NE Spain)

    NASA Astrophysics Data System (ADS)

    Quijano, Laura; Gaspar, Leticia; Navas, Ana

    2016-04-01

    Mediterranean mountain agroecosystems are prone to soil loss mainly due to the accelerated erosion as a consequence of human induced changes from agriculture and grazing practices over the last centuries and the climatic conditions (i.e. irregular and scarce precipitations and drought periods). Soil erosion leads to soil degradation inducing the loss of soil functions. The progressive decline of soil functions thereof soil quality is associated to a decrease of soil productivity and can threat the sustainability of cultivated soils. The use of fallout 137Cs as a soil movement tracer provides useful data to identify areas where loss and gain of 137Cs occurs and that of soil. This study aims to address soil movement and soil nutrient dynamics closely related to the status of soil degradation. A rain-fed cereal field (1.6 ha) representative of Mediterranean mountain agricultural landscapes (42°25'41''N 1°13'8''W) was selected to examine the effects of soil redistribution processes on the spatial variability of soil organic carbon (SOC) and nitrogen (SON) and their relationships with soil properties and topographic characteristics. From the hydrological point of view, the field is isolated due to the effect of landscape features and man-made structures. Climate is continental Mediterranean with an average annual rainfall of 500 mm and soils are Calcisols. The reference inventories of 137Cs and soil nutrients were established from 21 soil samples collected in nearby undisturbed areas under typical Mediterranean vegetation cover. A total of 156 bulk soil samples (30-50 cm depth) and 156 topsoil samples (5 cm) were collected on a 10 m grid. 137Cs and soil nutrients loss and gain areas were identified by comparing the reference inventories with the values of inventories at the sampling points. A new approach to characterize and measure active (ACF) and stable (SCF) carbon fraction contents by using a dry combustion method based on the oxidation temperature of carbon

  9. Vertical distribution and temporal changes of 137Cs in soil profiles under various land uses after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Takahashi, Junko; Tamura, Kenji; Suda, Tomoya; Matsumura, Ryo; Onda, Yuichi

    2015-01-01

    We monitored the vertical distribution of (137)Cs in soil profiles under eight different land uses for the 2 y after the Fukushima Dai-ichi Nuclear Power Plant accident, and discussed the temporal changes in the early-stage of the migration and the determinants of the initial distribution. The soil samples were collected for four surveys using a scraper plate at each study site, which consisted of three forests (mixed forest, mature cedar, and young cedar), two grasslands (pasture and meadow) and three abandoned agricultural fields (farm land, tobacco field, and paddy field). The land use patterns have a large influence on some soil properties and the migration processes of (137)Cs above ground, resulting in different distribution of (137)Cs in those soil profiles. Specifically, the secondary deposition of (137)Cs from the coniferous canopy, retention of (137)Cs by litter layer, and the homogenization of (137)Cs concentrations in surface soil by natural soil mixing such as the disturbance by cattle grazing, roots growing and the formation of needle ice were important to cause redistribution of the deposited (137)Cs. Only in the paddy field, the (137)Cs inventory in subsurface soils (5-10 cm) gradually increased and comprised 26% of the total (137)Cs in 2 y, showing the downward migration of (137)Cs to subsurface soil. In the other sites, it was considered that (137)Cs were strongly adsorbed by soil particles and rarely migrated downward as soluble form. Vertical distributions during the first survey were able to be used as the initial distributions and were well fitted to the exponential equation. The distribution parameters α (relaxation depth) and β (relaxation mass depth), calculated by the exponential equation were correlated with RIP (r = -0.806, p < 0.05), macro pore (r = 0.651, p = 0.11), and dispersible fine particle content (r = 0.856, p < 0.05). It indicated that the initial distribution would be influenced by the Cs fixation ability of

  10. Vertical distribution and temporal changes of 137Cs in soil profiles under various land uses after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Takahashi, Junko; Tamura, Kenji; Suda, Tomoya; Matsumura, Ryo; Onda, Yuichi

    2015-01-01

    We monitored the vertical distribution of (137)Cs in soil profiles under eight different land uses for the 2 y after the Fukushima Dai-ichi Nuclear Power Plant accident, and discussed the temporal changes in the early-stage of the migration and the determinants of the initial distribution. The soil samples were collected for four surveys using a scraper plate at each study site, which consisted of three forests (mixed forest, mature cedar, and young cedar), two grasslands (pasture and meadow) and three abandoned agricultural fields (farm land, tobacco field, and paddy field). The land use patterns have a large influence on some soil properties and the migration processes of (137)Cs above ground, resulting in different distribution of (137)Cs in those soil profiles. Specifically, the secondary deposition of (137)Cs from the coniferous canopy, retention of (137)Cs by litter layer, and the homogenization of (137)Cs concentrations in surface soil by natural soil mixing such as the disturbance by cattle grazing, roots growing and the formation of needle ice were important to cause redistribution of the deposited (137)Cs. Only in the paddy field, the (137)Cs inventory in subsurface soils (5-10 cm) gradually increased and comprised 26% of the total (137)Cs in 2 y, showing the downward migration of (137)Cs to subsurface soil. In the other sites, it was considered that (137)Cs were strongly adsorbed by soil particles and rarely migrated downward as soluble form. Vertical distributions during the first survey were able to be used as the initial distributions and were well fitted to the exponential equation. The distribution parameters α (relaxation depth) and β (relaxation mass depth), calculated by the exponential equation were correlated with RIP (r = -0.806, p < 0.05), macro pore (r = 0.651, p = 0.11), and dispersible fine particle content (r = 0.856, p < 0.05). It indicated that the initial distribution would be influenced by the Cs fixation ability of

  11. Status of (137)Cs contamination in marine biota along the Pacific coast of eastern Japan derived from a dynamic biological model two years simulation following the Fukushima accident.

    PubMed

    Tateda, Yutaka; Tsumune, Daisuke; Tsubono, Takaki; Misumi, Kazuhiro; Yamada, Masatoshi; Kanda, Jota; Ishimaru, Takashi

    2016-01-01

    Radiocesium ((134)Cs and (137)Cs) released into the Fukushima coastal environment was transferred to marine biota inhabiting the Pacific Ocean coastal waters of eastern Japan. Though the levels in most of the edible marine species decreased overtime, radiocesium concentrations in some fishes were still remained higher than the Japanese regulatory limit for seafood products. In this study, a dynamic food chain transfer model was applied to reconstruct (137)Cs levels in olive flounder by adopting the radiocesium concentrations in small demersal fish which constitute an important fraction of the diet of the olive flounder particularly inhabiting area near Fukushima. In addition, (137)Cs levels in slime flounder were also simulated using reported radiocesium concentrations in some prey organisms. The simulated results from Onahama on the southern border of the Fukushima coastline, and at Choshi the southernmost point where the contaminated water mass was transported by the Oyashio current, were assessed in order to identify what can be explained from present information, and what remains to be clarified three years after the Fukushima Dai-ichi nuclear power plant (1FNPP) accident. As a result, the observed (137)Cs concentrations in planktivorous fish and their predator fish could be explained by the theoretically-derived simulated levels. On the other hand, the slow (137)Cs depuration in slime flounder can be attributed to uptake from unknown sources for which the uptake fluxes were of a similar magnitude as the excretion fluxes. Since the reported (137)Cs concentrations in benthic invertebrates off Onahama were higher than the simulated values, radiocesium transfer from these benthic detritivorous invertebrates to slime flounder via ingestion was suggested as a cause for the observed slow depuration of (137)Cs in demersal fish off southern Fukushima. Furthermore, the slower depuration in the demersal fish likely required an additional source of (137)Cs, i

  12. Evaluation of the Relationship between Current Internal 137Cs Exposure in Residents and Soil Contamination West of Chernobyl in Northern Ukraine

    PubMed Central

    Kimura, Yuko; Okubo, Yuka; Hayashida, Naomi; Takahashi, Jumpei; Gutevich, Alexander; Chorniy, Sergiy; Kudo, Takashi; Takamura, Noboru

    2015-01-01

    After the Chernobyl Nuclear Power Plant accident, the residents living around the Chernobyl were revealed to have been internally exposed to 137Cs through the intake of contaminated local foods. To evaluate the current situation of internal 137Cs exposure and the relationship between the 137Cs soil contamination and internal exposure in residents, we investigated the 137Cs body burden in residents who were living in 10 selected cities from the northern part of the Zhitomir region, Ukraine, and collected soil samples from three family farms and wild forests of each city to measured 137Cs concentrations. The total number of study participants was 36,862, of which 68.9% of them were female. After 2010, the annual effective doses were less than 0.1 mSv in over 90% of the residents. The 137Cs body burden was significantly higher in autumn than other seasons (p < 0.001) and in residents living in more contaminated areas (p < 0.001). We also found a significant correlation between the proportion of residents in each city with an estimated annual exposure dose exceeding 0.1 mSv and 137Cs concentration of soil samples from family farms (r = 0.828, p = 0.003). In conclusion, more than 25 years after the Chernobyl accident, the internal exposure doses to residents living in contaminated areas of northern Ukraine is limited but still related to 137Cs soil contamination. Furthermore, the consumption of local foods is considered to be the cause of internal exposure. PMID:26402065

  13. Evaluation of the Relationship between Current Internal 137Cs Exposure in Residents and Soil Contamination West of Chernobyl in Northern Ukraine.

    PubMed

    Kimura, Yuko; Okubo, Yuka; Hayashida, Naomi; Takahashi, Jumpei; Gutevich, Alexander; Chorniy, Sergiy; Kudo, Takashi; Takamura, Noboru

    2015-01-01

    After the Chernobyl Nuclear Power Plant accident, the residents living around the Chernobyl were revealed to have been internally exposed to 137Cs through the intake of contaminated local foods. To evaluate the current situation of internal 137Cs exposure and the relationship between the 137Cs soil contamination and internal exposure in residents, we investigated the 137Cs body burden in residents who were living in 10 selected cities from the northern part of the Zhitomir region, Ukraine, and collected soil samples from three family farms and wild forests of each city to measured 137Cs concentrations. The total number of study participants was 36,862, of which 68.9% of them were female. After 2010, the annual effective doses were less than 0.1 mSv in over 90% of the residents. The 137Cs body burden was significantly higher in autumn than other seasons (p < 0.001) and in residents living in more contaminated areas (p < 0.001). We also found a significant correlation between the proportion of residents in each city with an estimated annual exposure dose exceeding 0.1 mSv and 137Cs concentration of soil samples from family farms (r = 0.828, p = 0.003). In conclusion, more than 25 years after the Chernobyl accident, the internal exposure doses to residents living in contaminated areas of northern Ukraine is limited but still related to 137Cs soil contamination. Furthermore, the consumption of local foods is considered to be the cause of internal exposure. PMID:26402065

  14. Evaluation of the Relationship between Current Internal 137Cs Exposure in Residents and Soil Contamination West of Chernobyl in Northern Ukraine.

    PubMed

    Kimura, Yuko; Okubo, Yuka; Hayashida, Naomi; Takahashi, Jumpei; Gutevich, Alexander; Chorniy, Sergiy; Kudo, Takashi; Takamura, Noboru

    2015-01-01

    After the Chernobyl Nuclear Power Plant accident, the residents living around the Chernobyl were revealed to have been internally exposed to 137Cs through the intake of contaminated local foods. To evaluate the current situation of internal 137Cs exposure and the relationship between the 137Cs soil contamination and internal exposure in residents, we investigated the 137Cs body burden in residents who were living in 10 selected cities from the northern part of the Zhitomir region, Ukraine, and collected soil samples from three family farms and wild forests of each city to measured 137Cs concentrations. The total number of study participants was 36,862, of which 68.9% of them were female. After 2010, the annual effective doses were less than 0.1 mSv in over 90% of the residents. The 137Cs body burden was significantly higher in autumn than other seasons (p < 0.001) and in residents living in more contaminated areas (p < 0.001). We also found a significant correlation between the proportion of residents in each city with an estimated annual exposure dose exceeding 0.1 mSv and 137Cs concentration of soil samples from family farms (r = 0.828, p = 0.003). In conclusion, more than 25 years after the Chernobyl accident, the internal exposure doses to residents living in contaminated areas of northern Ukraine is limited but still related to 137Cs soil contamination. Furthermore, the consumption of local foods is considered to be the cause of internal exposure.

  15. The Contribution of Sources to the Sustained Elevated Inventory of (137)Cs in Offshore Waters East of Japan after the Fukushima Dai-ichi Nuclear Power Station Accident.

    PubMed

    Takata, Hyoe; Kusakabe, Masashi; Inatomi, Naohiko; Ikenoue, Takahito; Hasegawa, Kazuyuki

    2016-07-01

    We have evaluated the contribution of sources of (137)Cs to the inventory of radiocesium in waters (surface area: 6160 km(2), water volume: 753 km(3)) off Fukushima Prefecture and neighboring prefectures from May 2011 to February 2015. A time-series of the inventory of (137)Cs in the offshore waters revealed a clearly decreasing trend from May 2011 (283.4 TBq) to February 2015 (1.89 TBq). The (137)Cs inventory about four years after the accident was approximately twice the background inventory of 1.1 TBq. The magnitudes of the (137)Cs influxes from sources into offshore waters for periods of 182-183 days were estimated from the first period (1 October 2011 to 31 March 2012: 15.3 TBq) to the last period (1 October 2014 to 31 March 2015: 0.41 TBq). We assumed that three sources contributed (137)Cs: continuous direct discharge from the Fukushima Dai-ichi Nuclear Power Station (FNPS) even after the massive discharge in late March 2011, desorption/dissolution from sediments, and fluvial input. Quantification of these sources indicated that the direct discharge from the FNPS is the principal source of (137)Cs to maintain the relatively high inventory in the offshore area. PMID:27282171

  16. Estimation of average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors by using the {sup 134}Cs/{sup 137}Cs ratio method

    SciTech Connect

    Endo, T.; Sato, S.; Yamamoto, A.

    2012-07-01

    Average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors is estimated, using the {sup 134}Cs/{sup 137}Cs ratio method for measured radioactivities of {sup 134}Cs and {sup 137}Cs in contaminated soils within the range of 100 km from the Fukushima Dai-ichi nuclear power plants. As a result, the measured {sup 134}Cs/{sup 137}Cs ratio from the contaminated soil is 0.996{+-}0.07 as of March 11, 2011. Based on the {sup 134}Cs/{sup 137}Cs ratio method, the estimated burnup of damaged fuels is approximately 17.2{+-}1.5 [GWd/tHM]. It is noted that the numerical results of various calculation codes (SRAC2006/PIJ, SCALE6.0/TRITON, and MVP-BURN) are almost the same evaluation values of {sup 134}Cs/ {sup 137}Cs ratio with same evaluated nuclear data library (ENDF-B/VII.0). The void fraction effect in depletion calculation has a major impact on {sup 134}Cs/{sup 137}Cs ratio compared with the differences between JENDL-4.0 and ENDF-B/VII.0. (authors)

  17. Migration of 137Cs in tributaries, lake water and sediment of Lago Maggiore (Italy, Switzerland) - analysis and comparison with Lago di Lugano and other lakes.

    PubMed

    Putyrskaya, Victoria; Klemt, Eckehard; Röllin, Stefan

    2009-01-01

    This paper describes the behaviour of 137Cs in Lago Maggiore and other pre-alpine lakes as a consequence of atmospheric nuclear weapons testing fallout and the fallout from the nuclear accident in Chernobyl. It presents data on the 137Cs distribution in tributaries, lake water, bottom sediments and reveals the role of (137)Cs as a marker of the sedimentation processes. The run-off of 137Cs from the watershed to the lake is described with a simple compartment model. Measurements of the activity concentration of (137)Cs in sediments are compared with the output of a model (diffusion-convection type) which describes the input of 137Cs into and its vertical distribution within the sediment. Varying sedimentation rates (0.05-0.90g(cm2y)(-1)) in Lago Maggiore are compared with data of other authors. Sedimentation rates and total distribution coefficients (of about 10(5) Lkg(-1)) in Lago Maggiore are discussed and compared with those of Lago di Lugano, Lake Constance, and Lake Vorsee. PMID:19019505

  18. Long-term decrease of atmospheric test {sup 137}Cs in the soil-prairie plant-milk pathway in southern Chile

    SciTech Connect

    Schuller, P. Ellies, A.; Handl, J.

    1998-07-01

    The time dependency of nuclear test {sup 137}Cs in soil, prairie plants, and milk was observed on pastures of seven dairy farms in the 10th Region, Chile, from 1982 to 1997, without any appreciable deposition of radioactive fallout after 1983. Whereas the {sup 137}Cs concentration in the soil decreased at a rate close to that of the radionuclide`s physical decay during the whole observation period, the rate of decrease of the {sup 137}Cs concentration in the prairie plants and in the milk, having been very rapid between 1982--1990, became slower between 1991--1997. The effective half-lives of the concentration in plants were found to be 5.6 y and 12 y during the first and second observation periods, respectively. Similar half-lives of 5.5 y and 13 y were found for the concentration decline in milk during each period. These data clearly demonstrate a reduction in the long-term decrease of the {sup 137}Cs plant uptake, and consequently in the decrease of the {sup 137}Cs concentration in milk, resulting from a decline of {sup 137}Cs availability for prairie plants in the Hapludand soils over the whole 15-y observation period.

  19. Experimental evidence of biomass burning as a source of atmospheric 137Cs, puy de Dôme (1465 m a.s.l.), France

    NASA Astrophysics Data System (ADS)

    Bourcier, L.; Sellegri, K.; Masson, O.; Zangrando, R.; Barbante, C.; Gambaro, A.; Pichon, J.-M.; Boulon, J.; Laj, P.

    2010-06-01

    The presence of cesium-137 ( 137Cs) in the environment is mainly due to past nuclear tests and accidental reactor releases. Due to the half-life of 137Cs (30.2 y), amounts of this radionuclide releases are in fact still detectable in soils, and at trace levels in the vegetation and the atmosphere. Since the middle of the 1990's, the presence of 137Cs in the atmosphere has long been attributed to the resuspension of terrestrial dust. Recently, modelling studies have demonstrated that an additional and possibly dominant source of this anthropogenic radionuclide is biomass burning. Here, we report the variations of atmospheric 137Cs activity levels over a 2-year period at the puy de Dôme (1465 m a.s.l.), France in combination with measurements of the aerosol chemical composition, in particular with indicators for biomass burning (levoglucosan and potassium) and soil dust (calcium). Temporal co-variations of these chemical compounds in addition to back-trajectories are used to identify common source emissions. Significant correlation is found between these compounds. Hence, we experimentally confirm the modelling study highlighting the fact that the atmospheric 137Cs is partly released by biomass burning. In addition, we observed that the correlations between the 137Cs concentrations and levoglucosan and biomass burning K + differ according to the season. This is in agreement with the temporal evolution of levoglucosan concentration, which has maxima in winter and minima in summer.

  20. Evaluation of the possibility to use the plant-microbe interaction to stimulate radioactive 137Cs accumulation by plants in a contaminated farm field in Fukushima, Japan.

    PubMed

    Djedidi, Salem; Terasaki, Akimi; Aung, Han Phyo; Kojima, Katsuhiro; Yamaya, Hiroko; Ohkama-Ohtsu, Naoko; Bellingrath-Kimura, Sonoko Dorothea; Meunchang, Phatchayaphon; Yokoyama, Tadashi

    2015-01-01

    Field experiments in a contaminated farmland in Nihonmatsu city, Fukushima were conducted to assess the effectiveness of the plant-microbe interaction on removal of radiocesium. Before plowing, 93.3% of radiocesium was found in the top 5 cm layer (5,718 Bq kg DW(-1)). After plowing, Cs radioactivity in the 0-15 cm layer ranged from 2,037 to 3,277 Bq kg DW(-1). Based on sequential extraction, the percentage of available radiocesium (water soluble + exchangeable) was fewer than 10% of the total radioactive Cs. The transfer of (137)Cs was investigated in three agricultural crops; komatsuna (four cultivars), Indian mustard and buckwheat, inoculated with a Bacillus or an Azospirillum strains. Except for komatsuna Nikko and Indian mustard, inoculation with both strains resulted in an increase of biomass production by the tested plants. The highest (137)Cs radioactivity concentration in above-ground parts was found in Bacillus-inoculated komatsuna Nikko (121 Bq kg DW(-1)), accompanied with the highest (137)Cs TF (0.092). Furthermore, komatsuna Nikko-Bacillus and Indian mustard-Azospirillum associations gave the highest (137)Cs removal, 131.5 and 113.8 Bq m(-2), respectively. Despite the beneficial effect of inoculation, concentrations of (137)Cs and its transfer to the tested plants were not very high; consequently, removal of (137)Cs from soil would be very slow.

  1. Accumulation and transfer of 137Cs and 90Sr in the plants of the forest ecosystem near the Ignalina Nuclear Power Plant.

    PubMed

    Lukšienė, B; Marčiulionienė, D; Gudelienė, I; Schönhofer, F

    2013-02-01

    The radioecological state of the forest ecosystem in the vicinity of the Ignalina Power Plant prior to decommissioning was analysed with specific emphasis on (137)Cs and (90)Sr activity concentrations in plant species growing in two reference sampling sites (Tilze and Grikiniskes). In the period of 1996-2008 the mean contamination of plants with (137)Cs was from 45 to 119 Bq/kg and with (90)Sr - from 3 to 42 Bq/kg. Measured (137)Cs TF values for soil-root transfer mainly ranged between 1.0-1.4, except for Calamagrostis arundinacea which had a TF value of 0.1. On average, the (137)Cs TF value from root to shoot was 1.7 fold higher than for soil to root transfer. (90)Sr TF values (soil-root) were in the range of 1.2-1.8 but for Calluna vulgaris it was 0.2. The mean root to shoot TF value for (90)Sr was 7.7 fold higher. These results indicate the higher (90)Sr bioavailability than that of (137)Cs in the forested area. The Grikiniskes reference site is located nearby the Ignalina NPP, specifically the heated water outlet channel, which results in altered microclimatic conditions. These specific microclimatic conditions result in relationships between (137)Cs TF (soil-root) values and pH, moisture and organic matter content in the soil at Grikiniskes which appear to be different to those at the Tilze reference sampling site. PMID:23085187

  2. Migration of 137Cs in tributaries, lake water and sediment of Lago Maggiore (Italy, Switzerland) - analysis and comparison with Lago di Lugano and other lakes.

    PubMed

    Putyrskaya, Victoria; Klemt, Eckehard; Röllin, Stefan

    2009-01-01

    This paper describes the behaviour of 137Cs in Lago Maggiore and other pre-alpine lakes as a consequence of atmospheric nuclear weapons testing fallout and the fallout from the nuclear accident in Chernobyl. It presents data on the 137Cs distribution in tributaries, lake water, bottom sediments and reveals the role of (137)Cs as a marker of the sedimentation processes. The run-off of 137Cs from the watershed to the lake is described with a simple compartment model. Measurements of the activity concentration of (137)Cs in sediments are compared with the output of a model (diffusion-convection type) which describes the input of 137Cs into and its vertical distribution within the sediment. Varying sedimentation rates (0.05-0.90g(cm2y)(-1)) in Lago Maggiore are compared with data of other authors. Sedimentation rates and total distribution coefficients (of about 10(5) Lkg(-1)) in Lago Maggiore are discussed and compared with those of Lago di Lugano, Lake Constance, and Lake Vorsee.

  3. Time Dependence of the (137)Cs Concentration in Particles Discharged from Rice Paddies to Freshwater Bodies after the Fukushima Daiichi NPP Accident.

    PubMed

    Yoshimura, Kazuya; Onda, Yuichi; Wakahara, Taeko

    2016-04-19

    The concentration of particulate (137)Cs in paddy fields, which can be a major source of (137)Cs entering the water system, was studied following the Fukushima Daiichi Nuclear Power Plant accident. To parametrize the concentration and to estimate the time dependence, paddy fields covering various levels of (137)Cs deposition were investigated over the period 2011-2013 (n = 121). The particulate (137)Cs concentration (kBq kg-SS(-1)) showed a significant correlation with the initial surface deposition density (kBq m(-2)). This suggests that the entrainment coefficient (m(2) kg-SS(-1)), defined as the ratio between the particulate (137)Cs concentration and the initial surface deposition density, is an important parameter when modeling (137)Cs wash-off from paddy fields. The entrainment coefficient decreased with time following a double exponential function. The decrease rate constant of the entrainment coefficient was clearly higher than that reported for other land uses and for river water. The difference in the decrease rates of the entrainment coefficient suggests that paddy fields play a major role in radiocesium migration through the water system. An understanding of the decrease rate of the entrainment coefficient of paddy fields is therefore crucial to understand the migration of radiocesium in the water system. PMID:26999252

  4. Accumulation and transfer of 137Cs and 90Sr in the plants of the forest ecosystem near the Ignalina Nuclear Power Plant.

    PubMed

    Lukšienė, B; Marčiulionienė, D; Gudelienė, I; Schönhofer, F

    2013-02-01

    The radioecological state of the forest ecosystem in the vicinity of the Ignalina Power Plant prior to decommissioning was analysed with specific emphasis on (137)Cs and (90)Sr activity concentrations in plant species growing in two reference sampling sites (Tilze and Grikiniskes). In the period of 1996-2008 the mean contamination of plants with (137)Cs was from 45 to 119 Bq/kg and with (90)Sr - from 3 to 42 Bq/kg. Measured (137)Cs TF values for soil-root transfer mainly ranged between 1.0-1.4, except for Calamagrostis arundinacea which had a TF value of 0.1. On average, the (137)Cs TF value from root to shoot was 1.7 fold higher than for soil to root transfer. (90)Sr TF values (soil-root) were in the range of 1.2-1.8 but for Calluna vulgaris it was 0.2. The mean root to shoot TF value for (90)Sr was 7.7 fold higher. These results indicate the higher (90)Sr bioavailability than that of (137)Cs in the forested area. The Grikiniskes reference site is located nearby the Ignalina NPP, specifically the heated water outlet channel, which results in altered microclimatic conditions. These specific microclimatic conditions result in relationships between (137)Cs TF (soil-root) values and pH, moisture and organic matter content in the soil at Grikiniskes which appear to be different to those at the Tilze reference sampling site.

  5. Quantitative retention of atmospherically deposited elements by native vegetation is traced by the fallout radionuclides 7Be and 210Pb.

    PubMed

    Landis, Joshua D; Renshaw, Carl E; Kaste, James M

    2014-10-21

    Atmospheric deposition is the primary mechanism by which remote environments are impacted by anthropogenic contaminants. Vegetation plays a critical role in intercepting atmospheric aerosols, thereby regulating the timing and magnitude of both contaminant and nutrient delivery to underlying soils. However, quantitative models describing the fate of atmospherically derived elements on vegetation are limited by a lack of long-term measurements of both atmospheric flux and foliar concentrations. We addressed this gap in understanding by quantifying weekly atmospheric deposition of the naturally occurring radionuclide tracers (7)Be and (210)Pb, as well as their activities in leaves of colocated trees, for three years in New Hampshire, U.S. The accumulation of both (7)Be and (210)Pb in deciduous and coniferous vegetation is predicted by a model that is based solely on measured atmospheric fluxes, duration of leaf exposure, and radioactive decay. Any "wash off" processes that remove (7)Be and (210)Pb from foliage operate with a maximum half-time of greater than 370 days (P > 99%), which is an order of magnitude longer than previously assumed. The retention of both (7)Be and (210)Pb on leaves is thus quantitative and permanent, coupling the fate of (7)Be, (210)Pb and similar atmospheric species to that of the leaf matter itself. These findings demonstrate that the long-standing paradigm of a short "environmental half-life" for atmospheric contaminants deposited on natural surfaces must be re-evaluated.

  6. Residence times of fine tropospheric aerosols as determined by {sup 210}Pb progeny.

    SciTech Connect

    Marley, N. A.; Gaffney, J. S.; Drayton, P. J.; Cunningham, M. M.; Mielcarek, C.; Ravelo, R.; Wagner, C.

    1999-10-05

    Fine tropospheric aerosols can play important roles in the radiative balance of the atmosphere. The fine aerosols can act directly to cool the atmosphere by scattering incoming solar radiation, as well as indirectly by serving as cloud condensation nuclei. Fine aerosols, particularly carbonaceous soots, can also warm the atmosphere by absorbing incoming solar radiation. In addition, aerosols smaller than 2.5 {micro}m have recently been implicated in the health effects of air pollution. Aerosol-active radioisotopes are ideal tracers for the study of atmospheric transport processes. The source terms of these radioisotopes are relatively well known, and they are removed from the atmosphere only by radioactive decay or by wet or dry deposition of the host aerosol. The progeny of the primordial radionuclide {sup 238}U are of particular importance to atmospheric studies. Uranium-238 is common throughout Earth's crust and decays to the inert gas {sup 222}Rn, which escapes into the atmosphere. Radon-222 decays by the series of alpha and beta emissions shown in Figure 1 to the long-lived {sup 210}Pb. Once formed, {sup 210}Pb becomes attached to aerosol particles with average attachment times of 40 s to 3 min.