Activity concentration of some anthropogenic radionuclides in the surface marine sediments near the Saudi coast of the Arabian (Persian) Gulf

International Nuclear Information System (INIS)

Al-Kheliewi, A.S.; Shabana, E.I.

2007-01-01

Activity concentrations of some anthropogenic radionuclides ( 90 Sr, 137 Cs, 238 Pu, 239+240 Pu and 241 Am) have been measured in the surface of marine sediments along the Saudi coast of the Arabian (Persian) Gulf. The samples were collected at different locations and water depths. The spatial distribution of the concentrations of the measured radionuclides showed a heterogeneous pattern and is independent of location or water depth. The obtained results are discussed and some conclusions are drawn. (author)

Activity concentrations and mean annual effective dose from gamma-emitting radionuclides in the Lebanese diet

International Nuclear Information System (INIS)

Nasreddine, L.; Hwalla, N.; El Samad, O.; Baydoun, R.; Hamze, M.; Parent-Massin, D.

2008-01-01

Since the primary factor contributing to the internal effective dose in the human organism is contaminated food, the control of radionuclides in food represents the most important means of protection. This study was conducted to determine the levels of the dietary exposure of the Lebanese population to gamma-emitting radioisotopes. The activity concentrations of gamma-emitting radioisotopes have been measured in food samples that represent the market basket of an adult urban population in Lebanon. The artificial radionuclide 137 Cs was measured above detection limits in only fish, meat and milk-based deserts. The most abundant natural radionuclide was 40 K (31-121 Bq kg -1 ), with the highest content in fish and meat samples. The annual mean effective dose contributed by 40 K in the reference typical diet was estimated equal to 186 μSv y -1 , a value reasonably consistent with findings reported by several other countries. (authors)

Environmental parameters series. 3. Concentration factors of radionuclides in freshwater organisms

International Nuclear Information System (INIS)

1994-03-01

This report outlines recent research activities of Radioactive Waste Management Center. Aiming to estimate the radiation dose of man exposed to radioactive materials in an environment, construction of a calculation model on the transfer of radionuclide in the environment was attempted. This issue, Environmental parameter series No.3 includes six reports on the factors related to environmental concentration for radionuclides. The title of the reports are as follows; Factors modifying the concentration factor (CF), Evaluation of accumulation of radionuclides in brackish water organisms, Dose assessment, CF derived from Japanese limnological data, Data table of CF and Metabolic parameters in relation to bioaccumulation of elements by organisms. In addition to collect and arrange the existing data, CF was calculated based on the concentration of stable elements in various lakes and rivers in Japan. (M.N.)

Radionuclide concentrations in oil extraction and production processes in Northeast Brazil

International Nuclear Information System (INIS)

Gazineu, Maria Helena Paranhos

2005-06-01

Since the beginning of the twentieth century the presence of naturally occurring radioactive material (NORM) was detected in the water and oil extracted from wells both onshore and offshore. The oil is extracted together with water and sediments which contain radionuclides of the uranium and thorium series. Among the radionuclides present, especial attention should be given to 226 Ra and 228 Ra, due to its long half-life and importance, from the radiological point of view. The objective of this work was to identify the natural radionuclides in the oil industry, to determine their activity concentration, and from these results, to evaluate the risks the employees of the oil industry are exposed to. Samples of sludge, scale and produced water extracted with the oil were collected from three oil processing stations in the state of Sergipe, Brazil. The activity concentrations of the radionuclides were determined in the solid samples before and after the extraction of the oil. The chemical and mineralogical composition of the samples without oil was evaluated. Water samples, on the other hand, were analyzed for their contents of radionuclides and barium concentration. It was observed that the activity concentrations of the analyzed radionuclides ( 226 Ra, 228 Ra, 228 Th and 210 Pb) in sludge and scales were very high when compared with the literature, particularly much higher than the values for 226 Ra and 228 Ra obtained for sludge and scales from the oil platforms near the city of Campos, state of Rio de Janeiro. The maximum concentration values for 226 Ra, 228 Ra, 228 Th and 210 Pb (3,500, 2,195, 2,248.6 and 201 kBq kg -1 , respectively) were obtained for the scales after the extraction of the oil. The analysis of the samples showed that barium sulphate (barite) and strontium sulphate (celestite) are the main constituents of the scales, while carbonates and silicates, together with other compounds are the components of sludge. A correlation between barium, 226 Ra and

Effect of cooking on radionuclide concentrations in waterfowl tissues

International Nuclear Information System (INIS)

Halford, D.K.

1983-01-01

Twenty-four commercially raised mallar ducks (Anas platyrhyncos) were released at the Test Reactor Area radioactive leaching ponds, and subsequently collected 56 to 188 days later. Liver, gizzard, and carcass were analyzed for radionuclide concentrations before and after cooking. Significant decreases (P 137 Cs, 134 Cs, 60 Co, 140 La and /sup 110m/Ag concentrations in carcass and liver samples occurred after cooking. Radionuclide concentrations in gizzard showed no significant change in radionuclide concentrations after cooking. Cesium-134 and 137 Cs concentrations decreased by 27% in carcass after cooking and reduced the dose commitment to man by that amount

Activity measurement and effective dose modelling of natural radionuclides in building material

International Nuclear Information System (INIS)

Maringer, F.J.; Baumgartner, A.; Rechberger, F.; Seidel, C.; Stietka, M.

2013-01-01

In this paper the assessment of natural radionuclides' activity concentration in building materials, calibration requirements and related indoor exposure dose models is presented. Particular attention is turned to specific improvements in low-level gamma-ray spectrometry to determine the activity concentration of necessary natural radionuclides in building materials with adequate measurement uncertainties. Different approaches for the modelling of the effective dose indoor due to external radiation resulted from natural radionuclides in building material and results of actual building material assessments are shown. - Highlights: • Dose models for indoor radiation exposure due to natural radionuclides in building materials. • Strategies and methods in radionuclide metrology, activity measurement and dose modelling. • Selection of appropriate parameters in radiation protection standards for building materials. • Scientific-based limitations of indoor exposure due to natural radionuclides in building materials

Proposal of limits for the concentration of radionuclides activity in drinking water for Polish population

International Nuclear Information System (INIS)

Filipiak, B.; Haratym, Z.

2008-01-01

The paper discussed the influence of the radionuclides contents in drinking water on the exposure of the population. The way of transformation of the limits of effective dose into the relevant concentration of radionuclides in drinking water is presented together with the results of these calculations. We propose to approve these limits for particular radionuclides. The suggestion for the methodology and organization of measurements are also given. (author)

Kinetic regularities of change in the concentration of radionuclides in the Georgian tea content

International Nuclear Information System (INIS)

Mosulishvili, L.M.; Katamadze, N.M.; Shoniya, N.I.; Ginturi, Eh.N.

1990-01-01

The paper is concerned with the results of a study of behavior of artificial radionuclides in Georgian tea technological products after the accident at the Chernobyl Nuclear Station. A partial contribution of the activity of radionuclides 141 Ce, 140 La, 103 Ru, 106 Ru, 140 Ba, 137 Cs, 95 Nb, 95 Zr, 134 Cs and 90 Sr to the total activity to Georgian tea samples. Maximum tolerated concentrations of radionuclides were assessed provided average annual tea consumption per capita was 1 kg. The maximum of solubility in the water phase falls on Cs radionuclides. The regularities of migration of half-lived radionuclides 3 yrs. After the Chernobyl accident were established

Radionuclides and selected trace elements in marine protein concentrates

Energy Technology Data Exchange (ETDEWEB)

Beasley, T M; Jokela, T A; Eagle, R J

1971-12-01

The concentrations of various trace elements and radionuclides have been measured in marine protein concentrates prepared from surface feeding fishes. As with concentrates prepared from benthic fishes, the /sup 210/Pb-/sup 210/Po pair are the most significant radionuclides present. Concentrations of stable Pb, Co and Ag in certain concentrates are sufficiently high to contribute substantially to estimated current intakes of these elements.

Natural radionuclides in food in an area with high concentrations of radionuclides

International Nuclear Information System (INIS)

Pereira, W.S.; Moraes, S.R.; Cavalcante, J.J.V.; Kelecom, A.; Silva, A.X. da; Lopez, J.M.; Filgueiras, R.; Carmo, A.S.

2017-01-01

Areas of high natural radiation expose the local population to doses greater than the world average. One of the routes of exposure is food intake. The activity concentration (AC) of 5 natural radionuclides in 7 types of foods was analyzed. The highest CA measured was 2.40 Bq.kg -1 for the U nat in the potato. The multivariate statistic identified two groups: (U nat e 232 Th) and [( 210 Pb and 228 Ra) and 226 Ra

Radionuclides concentration in marine environmental samples along the coast of Vietnam

International Nuclear Information System (INIS)

Nguyen Trong Ngo; Nguyen Thanh Binh; Nguyen Van Phuc; Le Nhu Sieu; Truong Y; Mai Thi Huong; Nguyen Thi Linh; Nguyen Mong Sinh; Phan Son Hai; Le Ngoc Chung; Dang Duc Nhan; Nguyen Quang Long; Nguyen Hao Quang; Tran Tuyet Mai

2009-01-01

Studies on radioactivity inventories in environmental samples are necessary as they will serve as baseline data for assessing any environmental impact usage of nuclear-based activities. Approximately 700 data on 238 U, 232 Th, 226 Ra, 90 Sr, 137 Cs, 239,240 Pu activity concentrations in 150 samples i.e. sea water, sediment, fish, mollusc, crustaceans, oyster and weeds samples collected from 7 various locations in Vietnam (Hai Phong, Nghe An, Khanh Hoa, Ninh Thuan, Binh Thuan, Vung Tau, Tien Giang) throughout 1999-2008 are summarised and presented in this paper. Generally, the levels of artificial radionuclides in the studied marine environmental samples are lower as compared to other Asia-Pacific countries while naturally occurred radionuclides activity concentrations obtained were found to be in accordance with respective data from other studies within Pacific region. The radionuclides bioaccumulation factors studied in Red laver and oyster were mostly found to be high; therefore, further reinvestigation should be done for these biota that will be used as bio-fingerprint indicators in monitoring the marine environment from nuclear-based pollutions. The data set obtained from this study is available to the Asia-Pacific Marine Radioactivity Database. (author)

Radionuclide concentrations in white sturgeon from the Columbia River

International Nuclear Information System (INIS)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1993-11-01

The objectives of this study were to (1) review and summarize historical data on radionuclide concentrations in white sturgeon from the Columbia River, (2) determine present-day radionuclide tissue burdens from different locations in the Columbia River, and (3) compare historical data with current data. We first reviewed and summarized the historical literature on radionuclide concentrations in white sturgeon from the Hanford Reach. Field studies were then conducted to evaluate the relationship among sample locations, age/length of white sturgeon, and present radionuclide tissue burdens. Results and comparisons are discussed in the remainder of this report

Rapid determination of radionuclide activity concentrations in contaminated drinking water

International Nuclear Information System (INIS)

Medley, P.; Ryan, B.; Bollhofer, A.; Martin, P.; International Atomic Energy Agency, Vienna

2007-01-01

As a result of an incident at the Ranger Uranium mine in which drinking water was contaminated with process water, it was necessary to perform quick analysis for naturally occurring uranium and thorium series radionuclide activity concentrations, including 226Ra, 210Pb, 210Po, U and Th isotopes. The methods which were subsequently used are presented here. The techniques used were high-resolution gamma spectrometry, Inductively Coupled Plasma Mass Spectrometry (ICPMS) and high-resolution alpha spectrometry. Routine methods were modified to allow for rapid analyses on priority samples in 1-2 days, with some results for highest priority samples available in less than 1 day. Comparison of initial results obtained through standard procedures, is discussed. An emphasis is placed on high-resolution alpha spectrometry of major alpha-emitting nuclides, specifically 226Ra, 230Th and 238U. The range of uranium concentrations in the samples investigated was from background levels to 6.6ppm. Implications for radiological dose assessment in contamination incidents involving process water are presented. The worst-case scenario for the incident at Ranger Uranium Mine indicates that the maximum committed effective dose to workers was well below the ICRP limit for worker-related dose and below the dose limit for a member of the public, with 230Th being the highest contributor

Concentration activities of natural radionuclides in three fish species in Brazilian coast and their contributions to the absorbed doses

International Nuclear Information System (INIS)

Pereira, Wagner de S.; Py Junior, Delcy de A.; Kelecom, Alphonse

2009-01-01

Activity concentrations of U-238, Ra-226, Pb-210, Th-232 e Ra-228 were analysed in three fish species at the Brasilian Coast. The fish 'Cubera snapper' (Lutjanus cyanopterus, Cuvier, 1828), in the region of Ceara and 'Whitemouth croaker' (Micropogonias furnieri, Desmarest, 1823) and 'Lebranche mullet' (Mugil liza, Valenciennes, 1836) in the region of Rio de Janeiro. These concentrations were transformed in absorbed dose rate using a dose conversion factor in unit of gray per year (μGy y -1 ), per becquerel per kilogram (Bq kg -1 ). Only the absorbed dose due to intake of radionuclides was examined, and the contributions due to radionuclides present in water and sediment were disregarded. The radionuclides were considered to be uniformly distributed in the fish body. The limit of the dose rate used, proposed by the Department of Energy of the USA, is equal to 3.65 10 03 mGy y -1 . The average dose rate due to the studied radionuclides is equal to 6.09 10 00 μGy y -1 , a value minor than 0.1% than the limits indicated by DOE, and quite similar to that found in the literature for 'benthic' fish. The most important radionuclides were the alpha emitters Ra-226 having 61 % of absorbed dose rate. U-238 and Th-232, each contributes with approximately 20 % of the absorbed dose rate. These three radionuclides are responsible for almost 100% of the dose rate received by the studied organisms. The beta emitters Ra-228 and Pb-210 account for approximately 1 % of the absorbed dose rate. (author)

Phytoremediation of soil contaminated with low concentrations of radionuclides

Energy Technology Data Exchange (ETDEWEB)

Entry, J A; Vance, N C; Hamilton, M A; Zabowski, D; Watrud, L S; Adriano, D C [Auburn University, Auburn, AL (United States). Dept. of Agronomy and Soils

1996-03-01

Ecsosytems throughout the world have been contaminated with radionuclides by above-ground nuclear testing, nuclear reactor accidents and nuclear power generation. Radioisotopes characteristics of nuclear fission, such as {sup 137}Cs and {sup 90}Sr, that are released into the environment can become more concentrated as they move up the food chain often becoming human health hazards. Natural environmental processes will redistribute long lived radionuclides that are released into the environment among soil, plants and wildlife. Numerous studies have shown that {sup 137}Cs and {sup 90}Sr are not removed from the top 0.4 metres of soil even under high rainfall, and migration rate from the top few centimetres of soil is slow. The top 0.4 meters of the soil is where plant roots actively accumulate elements. Since plants are known to take up and accumulate {sup 137}Cs and {sup 90}Sr, removal of these radionuclides from contaminated soils by plants could provide a reliable and economical method of remediation. One approach is to use fast growing plants inoculated with mycorrhizal fungi combined with soil organic amendments to maximize the plant accumulation and removal of radionuclides from contaminated soils, followed by harvest of above-ground portion of the plants. High temperature combustion would be used to oxidize plant material concentrating {sup 137}Cs and {sup 90}Sr in ash for disposal. When areas of land have been contaminated with radionuclides are large, using energy intensive engineering solutions to mediate huge volumes of soil is not feasible or economical. Plants are proposed as a viable and cost effective method to remove radionuclides from the soils that have been contaminated by nuclear testing and nuclear reactor accidents. 40 refs.

Activity measurement and effective dose modelling of natural radionuclides in building material.

Science.gov (United States)

Maringer, F J; Baumgartner, A; Rechberger, F; Seidel, C; Stietka, M

2013-11-01

In this paper the assessment of natural radionuclides' activity concentration in building materials, calibration requirements and related indoor exposure dose models is presented. Particular attention is turned to specific improvements in low-level gamma-ray spectrometry to determine the activity concentration of necessary natural radionuclides in building materials with adequate measurement uncertainties. Different approaches for the modelling of the effective dose indoor due to external radiation resulted from natural radionuclides in building material and results of actual building material assessments are shown. Copyright © 2013 Elsevier Ltd. All rights reserved.

Long-term calculation of radionuclides concentration in the ocean by OGCM

International Nuclear Information System (INIS)

Tsumune, Daisuke; Maruyama, Koki; Nakashiki, Norikazu; Aoyama, Michio; Hirose, Katsumi

2000-01-01

The ocean transports of radioactive materials have been carried out from Europe to Japan through the several routes on the world ocean. To sustain the safety of the transport of radioactive materials and to gain the public acceptance, it is necessary evaluate the radionuclide concentration in the ocean at the hypothetical submergence of radioactive materials into the world ocean. The purpose of this study is to develop a new method to evaluate the radionuclides concentration in the world ocean. A method to calculate the concentration of radionuclides in the ocean was developed using an ocean general circulation model (OGCM). The concentration of radionuclides ( 137 Cs, 90 Sr and 239+240 Pu) in the ocean was calculated from 1957 to 1994, on the assumption that these radionuclides were injected into the ocean only as the fallout from the atmospheric weapons tests. The calculated concentrations gave a good agreement with the observed data. The concentration of radionuclides in the ocean was estimated by this method in case of the hypothetical submergence of a package of fresh MOX fuel into the ocean on the routes of ocean transport from Europe to Japan. We calculated the concentration of 6 radionuclides ( 238 Pu, 239 Pu, 240 Pu, 241 Pu, 242 Pu and 241 Am) over 1000 years. It takes 3.5 CPU hours for 1000-year calculation by the supercomputer HITACHI S3800. The concentration in the ocean due to the hypothetical submergence of a package of fresh MOX fuel is estimated to be much smaller than the present background concentration of fallout. (author)

The concentration of fission products and other radionuclides in the surface air between 1971 and 1973

International Nuclear Information System (INIS)

Kolb, W.

1974-01-01

The aerosols collected with high-efficiency portable dust samplers in Brunswick and Tromsoe are analyzed in a Ge(Li) spectrometer. The mean monthly activity concentrations are given for a number of cosmogenic and induced radionuclides from nuclear weapons tests as well as for some cosmogenic and natural radionuclides. The annual curve exhibits marked seasonal variations with a pronounced peak - caused by an influx from the stratospheric reservoir - in late spring for all radionuclides studied except for 35 S, 210 Pb and 226 Ra. This peak decreases continuously from 1971 - 1973 for the fission products and induced radionuclides which for the most part had been produced in Chinese nuclear weapons tests. In contrast to 7 Be and 22 Na, the behaviour of 35 S suggests that it is partly anthropogenic in origin. The activity concentration of 226 Ra in air has been measured directly for the first time. The findings are discussed and finally compared with the maximum permissible concentration for the population. (orig./AK) [de

Influence of the composition of radionuclide mixtures on the maximum permissible concentration

International Nuclear Information System (INIS)

Schillinger, K.; Schuricht, V.

1975-08-01

By dividing radionuclides according to their formation mechanisms it is possible to assess the influence of separate partial mixtures on the maximum permissible concentration (MPC) of the total mixture without knowing exactly their contribution to the total activity. Calculations showed that the MPC of a total mixture of unsoluble radionuclides, which may occur in all fields of peaceful uses of nuclear energy, depends on the gastrointestinal tract as the critical organ and on the composition of the fission product mixture. The influence of fractionation on the MPC can be reglected in such a case, whereas in case of soluble radionuclides this is not possible

Assessment of fetal activity concentration and fetal dose for selected radionuclides based on animal and human data

International Nuclear Information System (INIS)

Roedler, H.D.

1987-01-01

Biokinetic data of selected radionuclide compounds from investigations in man and animal were taken from literature references with the purpose to provide a basis for a comparative assessment of fetal and adult radiation doses after intake or administration of radionuclides. The following ratios of fetal to adult doses were derived from human data: 0.5 for caesium 137 and total body, 2.3 for iron 59 and liver, 0.06 - 0.3 - 1.1 for iodine 131 and thyroid, and 0.1 - 0.3 for strontium 90 and bone. The ratios of activity concentrations in fetal and adult tissues are of considerable variability - up to three orders of magnitude. Further studies on fetal and adult biokinetics specifically designed for comparative dose assessment are indispensable. 106 refs.; 6 tabs

Permissible annual depositions and radionuclide concentrations in air

International Nuclear Information System (INIS)

Belyaev, V.A.; Golovko, M.Yu.

1993-01-01

It is established that it necessary to take into account the other ways of radionuclide intake apart from the inhalation one when determining the standards for radionuclide contamination of the atmospheric air. Whereby it is proposed to standardize annual depositions rather than permissible concentration in the atmospheric air for the ways related to radionuclide releases on the ground surface, which is explained by ambiguity of their dry deposition rate from the air. Formulae and results of calculation of standard characteristics are presented. The permissible radionuclide depositions, related to the intake through food chains are calculated with account for diet diversity, agroclimatic and phenological parameters in different regions of the country

Radionuclide concentrations in agricultural products near the Hanford Site, 1982 through 1992

International Nuclear Information System (INIS)

Antonio, E.J.

1994-06-01

The Pacific Northwest Laboratory reviewed monitoring data for agricultural products collected from 1982 through 1992 near the Hanford Site to determine radionuclide concentration trends. While samples were collected and analyzed, and results reported annual in Hanford Site environmental reports, an 11-year data set was reviewed for this report to increase the ability to assess trends and potential Hanford effects. Products reviewed included milk, chicken, eggs, beef, vegetables, fruit, wine, wheat, and alfalfa. To determine which radionuclides were detected sufficiently often to permit analysis for trends and effects, each radionuclide concentration and its associated uncertainty were ratioed. Radionuclides were considered routinely detectable if more than 50% of the ratios were between zero and one. Data for these radionuclides were then analyzed statistically, using analyses of variance. The statistical analyses indicated the following: for the most part, there were no measurable effects for Hanford operations; radionuclide concentrations in all products reviewed remained relatively low when compared to concentrations that would result in a 1-mrem effective dose equivalent to an individual; radionuclide concentrations are decreasing in general; however, 90 Sr concentrations in all media and 129 I in milk increased from 1982 to 1986, then decreased gradually for the remainder of the review period. The 129 I concentrations may be correlated with processing of irradiated reactor fuel at the Plutonium-Uranium Extraction (PUREX) Plant

Determination of radionuclide concentrations in animal feedstuffs for use following a nuclear emergency

International Nuclear Information System (INIS)

Hwang, W. T.; Ser, K. S.; Kim, E. H.; Choi, Y. K.; Han, M. H.; Choi, Y. H.

2001-01-01

The optimized derived intervention levels for animal products were evaluated based on cost-benefit analysis. From these results, the radionuclide concentrations in animal feedstuffs for use were derived. It was shown that radionuclide concentrations in animal feedstuffs for use depend strongly on animal products, radionuclides and feeding period. In case of the contaminated feedstuffs with long-lived radionuclides ( 137 Cs, 90 Sr), the feedstuffs with lower contamination should be supplied to animals with increase of feeding period due to the accumulation of radionuclides in animal products. While, in case of the contaminated feedstuffs with short-lived radionuclides ( 131 I), the feeding of higher contaminated feedstuffs was possible with increase of feeding period due to radionuclide decay. It was shown that 137 Cs concentration was lower than 90 Sr concentration in animal feedstuffs for use. It is primarily due to the higher feed-animal products transfer factor of 137 Cs

Air concentrations of Chernobyl fallout radionuclides in the area Debrecen (Hungary)

International Nuclear Information System (INIS)

Daroczy, S.; Dezsoe, Z.; Pazsit, A.; Buczko, Cs.M.; Somogyi, A.; Papp, Z.; Bolyos, A.; Nagy, J.; Raics, P.

1991-01-01

Measurements of aerosol activity from the Chernobyl reactor accident are reported. The concentrations of 14 radionuclides were obtained by gamma spectrometry for the period 30 April - 9 May, 1986. Gross beta measurements were also done through 11 August 1986 of which 137 Cs activity concentrations were derived. 90 Sr activity concentrations were also determined for selected aerosol samples using nondestructive procedure. The time course of contamination observed in Debrecen (Hungary) is discussed in terms of trajectory analysis. Isotopic ratios are also used to trace down routes of contamined air. In addition, such ratios are also used to characterize the status of the damaged reactor at different times. (author) 15 refs.; 2 figs

Radionuclide concentrations in white sturgeon from the Columbia River. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1993-11-01

The objectives of this study were to (1) review and summarize historical data on radionuclide concentrations in white sturgeon from the Columbia River, (2) determine present-day radionuclide tissue burdens from different locations in the Columbia River, and (3) compare historical data with current data. We first reviewed and summarized the historical literature on radionuclide concentrations in white sturgeon from the Hanford Reach. Field studies were then conducted to evaluate the relationship among sample locations, age/length of white sturgeon, and present radionuclide tissue burdens. Results and comparisons are discussed in the remainder of this report.

Methods of Increasing the Performance of Radionuclide Generators Used in Nuclear Medicine: Daughter Nuclide Build-Up Optimisation, Elution-Purification-Concentration Integration, and Effective Control of Radionuclidic Purity

Directory of Open Access Journals (Sweden)

Van So Le

2014-06-01

Full Text Available Methods of increasing the performance of radionuclide generators used in nuclear medicine radiotherapy and SPECT/PET imaging were developed and detailed for 99Mo/99mTc and 68Ge/68Ga radionuclide generators as the cases. Optimisation methods of the daughter nuclide build-up versus stand-by time and/or specific activity using mean progress functions were developed for increasing the performance of radionuclide generators. As a result of this optimisation, the separation of the daughter nuclide from its parent one should be performed at a defined optimal time to avoid the deterioration in specific activity of the daughter nuclide and wasting stand-by time of the generator, while the daughter nuclide yield is maintained to a reasonably high extent. A new characteristic parameter of the formation-decay kinetics of parent/daughter nuclide system was found and effectively used in the practice of the generator production and utilisation. A method of “early elution schedule” was also developed for increasing the daughter nuclide production yield and specific radioactivity, thus saving the cost of the generator and improving the quality of the daughter radionuclide solution. These newly developed optimisation methods in combination with an integrated elution-purification-concentration system of radionuclide generators recently developed is the most suitable way to operate the generator effectively on the basis of economic use and improvement of purposely suitable quality and specific activity of the produced daughter radionuclides. All these features benefit the economic use of the generator, the improved quality of labelling/scan, and the lowered cost of nuclear medicine procedure. Besides, a new method of quality control protocol set-up for post-delivery test of radionuclidic purity has been developed based on the relationship between gamma ray spectrometric detection limit, required limit of impure radionuclide activity and its measurement

Trends in radionuclide concentrations for wildlife and food products near Hanford for the period 1971 through 1988

International Nuclear Information System (INIS)

Eberhardt, L.E.; Cadwell, L.L.; Price, K.R.; Carlile, D.W.

1989-10-01

The objective of this summary investigation was to identify trends in radionuclide concentrations for wildlife and food products sampled from 1971 through 1988 as part of the Hanford Site Environmental Monitoring Program. No upward trends in radionuclide concentrations were detected for any wildlife or food products. Several sample types demonstrated significantly declining radionuclide concentrations. Three factors appeared to be responsible for the trends. First, the cessation of atmospheric testing by the United States and Soviet Union in 1971 contributed to the decline of radionuclides in some samples. Second, contaminants discharged to the Columbia River were reduced subsequent to the 1971 shutdown of the last Hanford nuclear reactor that used a once-through cooling water design. The reactor closing resulted in declines in activation products in oysters from Willapa Bay and in whitefish from the Hanford Reach of the Columbia River. Third, reductions in radionuclide concentrations in Hanford wildlife suggested a decreasing availability of environmental contaminants to wildlife. Remediation of areas having environmental surface contaminants on the Hanford Site was identified as a probable cause. 5 refs., 4 figs., 2 tabs

Activity concentrations of primordial radionuclides in sediments of surface - water dams in southwest Nigeria - a baseline survey

International Nuclear Information System (INIS)

Isinkaye, M.O.; Farai, I.P.

2008-01-01

The radionuclide contents of sediment samples collected from 20 surface-water dams in southwestern Nigeria have been determined by low-level gamma-spectroscopy. The average concentration of 40 K in each of the dams varied between 110.9±11.9 Bq kg-1 and 1025.9±36.8 Bq kg -1 with an overall mean (±SD) of 549.3 ± 247.6 Bq kg -1 while that of 238 U varied from 17.1±3.6 to 51.9±8.7 Bq kg -1 with an overall mean (±SD) of 27.6±8.5 Bq kg -1 and that of 232 Th varied from 26.2 ±3.6 Bq kg -1 to 130.1±23.7 Bq kg -1 with overall mean (±SD) of 62.0±26.1 Bq kg -1 . The variability of the values shows the wide disparity in the measured activity concentrations. The mean radium equivalent of 158.9 Bq kg -1 was calculated for the sediments in the dams. No artificial gamma emitting radionuclide was detected in the samples. (authors)

Radionuclide concentrations in white sturgeons from the Hanford Reach of the Columbia River

International Nuclear Information System (INIS)

Dauble, D.D.; Poston, T.M.

1994-01-01

We summarized radionuclide concentrations in white sturgeons Acipenser transmontanus from the Columbia River during a period when several plutonium-production reactors were operating at the Hanford Site in Washington State and compared these values to those measured several years after reactor shutdown. Studies conducted in the Hanford Reach of the Columbia River during 1953-1955 indicated that high concentrations of radionuclides (as total beta) were present in some internal organs on the external surface of white sturgeons. Average concentrations were about 1,480 Bq/kg for liver and kidney and exceeded 2,200 Bq/kg for fins and scutes. The principal radionuclides in the tissues of white sturgeons from the Hanford Reach during 1963-1967, the peak reactor operation interval, were 32 P, 65 Zn, and 51 Cr. Average concentrations of 32 P in muscle ranged from 925 to 2,109 Bq/kg and were typically two to seven times greater than 65 Zn. Average concentrations of radionuclides were usually in the order of gut contents much-gt carcass > muscle. Studies from 1989 to 1990 showed that radionuclide concentrations had decreased dramatically in white sturgeon tissue since the time of reactor operation. Maximum concentrations for artificial radionuclides ( 90 Sr, 60 Co, 137 Cs) in muscle and cartilage of white sturgeons in the Columbia River had declined to less than 4 Bq/kg. Formerly abundant radionuclides, including 32 P, 65 Zn, and 51 Cr, could not be detected in recent tissue samples. Further, radionuclide tissue burden in populations of sturgeons from the Hanford Reach and the upstream or downstream reference locations did not differ significantly. 34 refs., 3 figs., 4 tabs

Radionuclide concentration in ground-level air in 1991 in North Germany

International Nuclear Information System (INIS)

Kolb, W.; Wershofen, H.

1992-03-01

The activity concentration of various fission products and some other radionuclides (e.g. Be-7, Na-22, K-40 and Pb-210) contained in ground-level air were determined by gamma-ray spectroscopy. Weekly and mean monthly activity concentrations measured in Brunswick and Berlin are tabulated. From 1990 to 1991 the Cs-137 concentration in Brunswick decreased only slightly. It was less than 0.1% of that in 1986 but due to resuspended soil dust still three times higher than in 1985. Occasionally, traces of activation products were detected such as Cr-51, Mn-54 or Co-60 in Januray and February in Brunswick and Berlin. The effective equivalent dose due to the inhalation of fission products is estimated to be less than 0.1% of the Pb-210 inhalation dose. (orig.) [de

Concentration of radionuclides in fresh water fish downstream of Rancho Seco Nuclear Generating Plant

International Nuclear Information System (INIS)

Noshkin, V.E.; Eagle, R.J.; Dawson, J.M.; Brunk, J.L.; Wong, X.M.

1984-01-01

Fish were collected for radionuclide analysis over a 5-month period in 1984 from creeks downstream of the Rancho Seco Nuclear Generating Plant, which has been discharging quantities of some fission and activation products to the waterway since 1981. Among the fish, the bluegill was selected for intensive study because it is very territorial and the radionuclide concentrations detected should be representative of the levels in the local environment at the downstream locations sampled. Among the gamma-emitting radionuclides routinely released, only 134 Cs and 137 Cs were detected in the edible flesh of fish. Concentrations in the flesh of fish decreased with distance from the plant. The relationship between concentration and distance was determined to be exponential. Exponential equations were generated to estimate concentrations in fish at downstream locations where no site-specific information was available. Mean concentrations of 137 Cs in bluegill collected during April, May, July and August from specific downstream stations were not significantly different in spite of the release of 131 mCi to the creeks between April and August. The concentrations in fish are not responding to changes in water concentrations brought about by plant discharges. Diet appears to be a more significant factor than size or weight or water concentration in regulating body burdens of 137 Cs in these fish

Reconstructing historical radionuclide concentrations along the east coast of Ireland using a compartmental model

International Nuclear Information System (INIS)

Smith, C.N.; Clarke, S.; McDonald, P.; Goshawk, J.A.; Jones, S.R.

2000-01-01

A mathematical model is presented that simulates the annually averaged transport of radionuclides, originating from the BNFL reprocessing plant at Sellafield, throughout the Irish Sea. The model, CUMBRIA77, represents the processes of radionuclide transport and dispersion in the marine environment and allows predictions of radionuclide concentration in various environmental media, including biota, to be made throughout the whole of the Irish Sea. In this paper we describe the use of the model to reconstruct the historical activity concentrations of 137Cs and 239+240Pu in a variety of environmental media in the western Irish Sea and along the Irish east coast back to 1950. This reconstruction exercise is of interest because only limited measurements of 137Cs and 239+240Pu activity are available prior to the 1980s. The predictions were compared to the available measured data to validate their accuracy. The results of the reconstruction indicate that activity concentrations of 137Cs in the western Irish Sea follow a similar, though slightly delayed and smoothed, profile to the discharges from the Sellafield site, with concentrations at the time of peak discharge (the mid-1970s) being around an order of magnitude higher than those measured in the 1980s and 1990s. By contrast, the concentrations of 239+240Pu at the time of peak discharges were similar to those presently measured. These differences reflect the distinct marine chemistries of the two nuclides, in particular the higher propensity of plutonium to bind to sediments leading to extended transport times. Despite these differences in behaviour the doses to Irish seafood consumers from 137Cs remain significantly higher than those from 239+240Pu

Harmonization of standards for permissible radionuclide activity concentrations in foodstuffs in the long term after the Chernobyl accident.

Science.gov (United States)

Balonov, Mikhail I; Kashparov, Valery; Nikolaenko, Elena; Berkovsky, Volodymyr; Fesenko, Sergey

2018-04-16

The article critically examines the practice of post-Chernobyl standardization of radionuclide concentrations (mainly 137Cs and 90Sr) in food products in the USSR and the successor countries of Belarus, Russia and Ukraine. Recommendations are given on potential harmonization of these standards of radionuclide concentrations in food products among three countries, taking into account substantial international experience. We propose to reduce the number of product groups for standardization purpose from the current several dozens to three to five groups to optimize radiation control and increase the transparency of the process. We recommend five product groups for the standardization of 137Cs and three groups for 90Sr in food in radiocontaminated areas. The values of standards for individual product groups are recommended to be set proportionally to the measured specific activity in each of these groups, which will reduce unreasonable food rejection. The standards might be set for the entire country, and could be also used to control imports from other countries as well as exports to other countries. The developed recommendations were transferred in 2015-2016 to the regulatory authorities of the three countries. © 2018 IOP Publishing Ltd.

Nondestructive measurement for radionuclide concentration distribution in soil column

International Nuclear Information System (INIS)

Ogawa, Hiromichi; Ohnuki, Toshihiko; Yamamoto, Tadatoshi; Wadachi, Yoshiki

1985-01-01

A nondestructive method has been studied for determining the concentration of radionuclide (Cs-137) distributed in a soil column. The concentration distribution was calculated from the counting rate distribution using the efficiency matrix of a detector. The concentration distribution obtained by this method, with measuring efficiencies of theoretical calculation, coincides well with that obtained by the destructive sampling method. This method is, therefore, found to be effective for the measurement of one dimensional concentration distribution. The measuring limit of this method is affected not only by the radionuclide concentration but also by the shape of concentration distribution in a soil column and also by the way it is divided into concentration blocks. It is found that, the radioactive concentration up to 2.6 x 10 -4 μCi/g (9.62 Bq/g), and also the distribution up to where the concentration reduces to half at every 1 cm of depth, can be measured by this system. The concentration blocks can be divided into 1 cm of thickness as a minimum value. (author)

Concentration factors of radionuclides in the marine organisms

International Nuclear Information System (INIS)

1996-03-01

Parameters related to the bioconcentration of radionuclides in the marine were shown by 'Assessment and guideline to the target value of dose in the environment of the power light water reactor facilities' (Nuclear Safety Commission), but the guideline data did not contain Ru and Ce relating to the reprocessing plant. So that more new data than these of 'Technical Reports Series No. 247' (published by IAEA in 1985) were mainly collected. Especially the data of nuclides with poor data of concentration factors (CF) and natural radionuclides (Po-210, Pb-210) were gathered. These data were pigeonholed and many tables (element, kinds of organisms, experimental methods) were made by separating the general remarks from the original experimental reports. The contents of this report are given as under, history of concentration factor (CF), determination method of CF, CF calculation method, calculation models related to CF, tables of metabolic parameters, tables of CF, the present conditions of studies for uptake of radionuclides with long half-life into the marine organisms, CF abstract tables and trial calculation of human exposure by eating the marine organisms. (S.Y.)

Radionuclide concentrations in white sturgeon from the Columbia River

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy`s Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

Radionuclide concentrations in white sturgeon from the Columbia River

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

Radionuclide concentrations in white sturgeon from the Columbia River

International Nuclear Information System (INIS)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River

Transport of radionuclides by concentrated brine in a porous medium with micropore-macropore structure

International Nuclear Information System (INIS)

Hassanizadeh, S.M.

1987-01-01

This work concerns itself with the study of effects of soil aggregation and high salt concentrations on the transport of radionuclides by concentrated brine flowing through an aggregated porous medium. The medium is considered to be composed of porous rock aggregates separated by macropores through which the brine flows and transport of salt and radionuclides takes place. The aggregates contain dead-end pores, cracks, and stationary pockets collectively called micropores. The micropore space does not contribute to the flow, but it serves as a storage for salt and radionuclides. Adsorption of radionuclides takes place at internal surfaces of aggregates where they assume that a linear equilibrium isotherm describes the process. A one-dimensional numerical model is developed which is based on two sets of equations: one set for the flow and transport of salt and another set for transport of radionuclides. Results of numerical experiments clearly indicate that the existence of high salt concentrations markedly reduces the peak of nuclides concentration and slows down their movement. Also, it is found that diffusive mass exchange between macropores and aggregates results in a pronounced lowering of the radionuclides concentration peaks. 9 references, 7 figures

Radionuclide concentrations in wild waterfowl using the test reactor area radioactive leaching pond

International Nuclear Information System (INIS)

Halford, D.K.; Millard, J.B.; Markham, O.D.

1978-01-01

Waterfowl use the Test Reactor Area (TRA) Radioactive Leaching Pond on the Idaho National Engineering Laboratory Site (INEL Site) as a resting area. Daily observations of waterfowl were made to determine species composition and numbers. Eight ducks and one coot were collected from the TRA pond during 1976 and 1977. Seven background samples were also collected. Each bird was dissected and tissue samples were analyzed for gamma-emitting radionuclides. Duck tissues contained 25 radionuclides. Average and maximum radionuclide concentrations were highest in gut followed by feathers, liver, and muscle, Chromium-51 had the highest concentrations of all radionuclides identified 130,000 pCi/g (4800 Bq/g) in the gut and 37,500 pCi/g (1390 Bq/g) on the feathres). Neodymium-147 had the highest concentration on feathers of any radionuclide (104,000 pCi/g, 3850 Bq/g). Cesium-137 was the predominant radionuclide in muscle with a maximum concentration of 4,070 pCi/g (150 Bq/g). The ducks had lower radionuclide concentrations in the edible tissues than in the non-edible tissues. Potential whole-body and thyroid dose commitments to man consuming contaminated ducks were calculated using muscle concentrations of Cs-134, Cs-137, and I-131. Although assumptions used for dose calculations maximized the dose commitment to man, results indicated that consumption of contaminated duck tissue is not a radiation hazard to humans. Even the highest dose commitments were below the limits recommended for individuals of the general population by the Internatioal Commission on Radiological Protection (ICRP). The highest potential dose commitment to man would result from the consumption of an American coot known to have spent 20 days on the TRA pond. The average dose commitment to man would be 20 mrem

Measurement of activity concentration of primordial radionuclides in the soil samples of Tiruchirappalli, Tamil Nadu, India

International Nuclear Information System (INIS)

Sadiq Bukhari, A.; Saiyad Musthafa, M.; Syed Mohamed, H.E.; Krishnamoorthy, R.; Shahul Hameed, M.M.; Shahul Hameed, P.

2008-01-01

Full text: Radioactive minerals such as uranium ( 238 U), thorium ( 232 Th) and potassium ( 40 K) are considered to be Primordial radionuclides which are widely distributed in the earth's crust. Gamma-radiation from these radionuclides represents the main external source of irradiation for the human body. Human beings are exposed outdoors to the natural terrestrial radiation that originates predominantly from the upper 30 cm of the soil. A pilot project was therefore initiated aiming at systematically measuring the terrestrial gamma radiation in Tiruchirappalli city, Tamil Nadu, South India and to establish baseline data on the terrestrial background radiation level determining its contribution to the annual effective dose equivalent to the human population. The natural radioactivity concentrations were studied in soil samples collected from 50 locations in Tiruchirappalli city. The concentration varies significantly over different soil types and the highest radioactivity was measured over soil types of granite origin followed by red soil and alluvial loam. The mean activity concentrations of 232 Th, 238 U and 40 K in soil samples are found to be 81.78 Bq.kg -1 , 32.62 Bq.kg -1 , and 551.35 Bq.kg -1 respectively. The calculated gamma dose from the soil is in the range between 38.86nGy.h -1 and 240.59 nGy.h -1 with a mean value of 89.76 nGy.h -1 . The mean annual effective dose to the population from outdoor terrestrial gamma radiation was estimated to be 0.11mSv.y -1 which is low as compared with the maximum permissible effective dose equivalent of 1mSv.y -1 (ICRP,1991). In the present study it is observed that the major sources of gamma radiation in soils are mainly derived from rocky area with granite basement. (author)

Evaluation of radionuclide concentrations in high-level radioactive wastes

International Nuclear Information System (INIS)

Fehringer, D.J.

1985-10-01

This report describes a possible approach for development of a numerical definition of the term ''high-level radioactive waste.'' Five wastes are identified which are recognized as being high-level wastes under current, non-numerical definitions. The constituents of these wastes are examined and the most hazardous component radionuclides are identified. This report suggests that other wastes with similar concentrations of these radionuclides could also be defined as high-level wastes. 15 refs., 9 figs., 4 tabs

Correlation between meteorological conditions and the concentration of radionuclides in the ground layer of atmospheric air

International Nuclear Information System (INIS)

Krajny, E.; Osrodka, L.; Wojtylak, M.; Michalik, B.; Skowronek, J.

2001-01-01

The main goal of this work was to find correlation between the concentrations of radionuclides in outdoor air and the meteorological conditions like: atmospheric pressure, wind velocity and amount of precipitation. Because the sampling period of radionuclides concentrations in air was relatively long (7 days), the average levels of meteorological parameters have been calculated within the same time. Data of radionuclide concentrations and meteorological data have been analyzed in order to find statistical correlation. The regression analysis and one of AI methods, known as neural network, were applied. In general, analysis of the gathered data does not show any strong correlation between the meteorological conditions and the concentrations of the radionuclides in air. A slightly stronger correlation we found for radionuclides with relatively short half-lives. The only positive correlation has been found between the 7 Be concentration and air temperature (at the significance level α = 0.05). In our opinion, the lack of correlation was caused by a too long sampling time in measurements of radionuclides in outdoor air (a whole week). Results of analysis received by means of the artificial neuron network are better. We were able to find certain groups of meteorological conditions, related with the corresponding concentrations of particular radionuclides in air. Preliminary measurements of radon progeny concentration support the thesis that the link between changes of meteorological parameters and concentrations of radionuclides in ambient air must exist. (author)

Radionuclide concentrations in ground level air and precipitation in South Germany from 1976 to 1982

International Nuclear Information System (INIS)

Hoetzl, H.; Rosner, G.; Winkler, R.

1983-08-01

The activity concentrations of fallout radionuclides from atmospheric nuclear test explosions and of Be-7 in ground level air and precipitation have been determined by the Institut fuer Strahlenschutz at Munich-Neuherberg since 1970. While methods and results from 1970 to 1975 have been published in a previous report, the present report describes the revised program which includes now the naturally occurring nuclides Pb-210 and Po-210, as well as H-3. Sampling methods, analytical techniques and measuring procedures are given. The results up to the end of 1982 are reported and seasonal and long-term variations of radionuclide concentrations as well as frequency distributions of the data are discussed. The data are compared with those of other stations. As a consequence of some recent atmospheric nuclear test explosions by the People's Republic of China also short-lived radionuclides have been detected in ground level air and precipitation. The radiation exposure due to the radioactivity in ground level air and precipitation is estimated. (orig.)

Models and data to predict radionuclide concentrations in river basin systems

International Nuclear Information System (INIS)

Fleming, G.; Rufai, G.G.

1990-01-01

Radioactive contamination of land may result from the detonation of nuclear weapons or nuclear accidents, such as Chernobyl. The deposition of fallout on soil and/or plants, and subsequent erosion by rainsplash and overland flow, could introduce radioactive isotopes into the water and soil resources of the environment. A model to simulate the transport and deposition of concentrated pollutants and radionuclides within the river basin is proposed. The proposed model is built on an existing Strathclyde River Basin Model, (SRBM), which has the potential to simulate runoff and erosion and the distribution of eroded soil particle sizes. An algorithm of the processes of concentration of pollutants and radionuclides can be developed based on the current understanding of the process of radionuclide attachment to soil particles. (author)

The concentration of natural radionuclides in various types of building materials in Slovakia

Energy Technology Data Exchange (ETDEWEB)

Cabanekova, H [Inst. of Peventive and Clinical Medicine, Bratislava (Slovakia)

1996-12-31

The concentration of the natural radionuclides in various types of building materials was determined by the gamma spectrometry analysis using 130 cm{sup 3} high purity germanium detector and MCA LIVIUS 2000. Radium-226 and thorium-232 was assessed through their progeny photo peaks. The specific activity of both nuclides as weighted average of their photo peaks was determined. Potassium-40 was measured directly via its 1460 keV peak. The radium equivalent activity was calculate from specific activities of radium-226, thorium-232 and potassium-40. All samples were measured in 4{sup p}i{sup g}eometry. The building materials and products were milled and screened with 2-3 mm sieve. After drying the samples were stored in 450 cm{sup 3} sealed polyethylene container for 30 days ingrowing period. The results of analysis are corrected to the background distribution and to the self absorption in the volume of the samples. The efficiency calibration is realized using the reference sources distributed by IAEA in Vienna and by the Institute for Radionuclide Production in Prague The measured activity concentrations of the buildings materials are given. There are shown the minimum and maximum values for different investigated materials. (J.K.) 4 tabs., 5 refs.

Waste Form and Indrift Colloids-Associated Radionuclide Concentrations: Abstraction and Summary

International Nuclear Information System (INIS)

Aguilar, R.

2003-01-01

This Model Report describes the analysis and abstractions of the colloids process model for the waste form and engineered barrier system components of the total system performance assessment calculations to be performed with the Total System Performance Assessment-License Application model. Included in this report is a description of (1) the types and concentrations of colloids that could be generated in the waste package from degradation of waste forms and the corrosion of the waste package materials, (2) types and concentrations of colloids produced from the steel components of the repository and their potential role in radionuclide transport, and (3) types and concentrations of colloids present in natural waters in the vicinity of Yucca Mountain. Additionally, attachment/detachment characteristics and mechanisms of colloids anticipated in the repository are addressed and discussed. The abstraction of the process model is intended to capture the most important characteristics of radionuclide-colloid behavior for use in predicting the potential impact of colloid-facilitated radionuclide transport on repository performance

Waste Form and Indrift Colloids-Associated Radionuclide Concentrations: Abstraction and Summary

Energy Technology Data Exchange (ETDEWEB)

R. Aguilar

2003-06-24

This Model Report describes the analysis and abstractions of the colloids process model for the waste form and engineered barrier system components of the total system performance assessment calculations to be performed with the Total System Performance Assessment-License Application model. Included in this report is a description of (1) the types and concentrations of colloids that could be generated in the waste package from degradation of waste forms and the corrosion of the waste package materials, (2) types and concentrations of colloids produced from the steel components of the repository and their potential role in radionuclide transport, and (3) types and concentrations of colloids present in natural waters in the vicinity of Yucca Mountain. Additionally, attachment/detachment characteristics and mechanisms of colloids anticipated in the repository are addressed and discussed. The abstraction of the process model is intended to capture the most important characteristics of radionuclide-colloid behavior for use in predicting the potential impact of colloid-facilitated radionuclide transport on repository performance.

Radionuclide concentration in fuels and ash products from biofuel heating plants

International Nuclear Information System (INIS)

Erlandsson, B.; Hedvall, R.; Mattsson, S.

1995-01-01

The activity concentration of the radionuclides K-40, Ac-228, Pa-234, Mn-54, Co-60, Zr-95, Ru-106, Ag-110m, Sb-125, Cs-134, Cs-137 and Ce-144 have been investigated in peat wood chips and ash products from 13 Swedish district heating plants during the winter seasons of 1986/1987, 1988/89, 1989/90 and 1990/91. There is a significant decrease in the activity concentration of Cs-137 in the fuel which is especially pronounced between the first two seasons, 86/87 and 88/89 after the Chernobyl accident. In spite of the varying deposition of Cs-137 over the country it has been possible to give a relation between the activity concentration in the peat and wood chips as a function of the deposition. The Swedish biofuel heating plants of which 35-40 are burning peat and 70-75 chips have been divided in three groups according to the activity concentration in the ash products. The mean Cs-137 concentration in ash and the total activity 'produced' per year in Sweden have been calculated. The maximum concentration in air at ground level and the corresponding effective dose rate of inhaled Cs-137 as a function of the emission rates of flue gases from stacks with varying heights and during different weather conditions has been calculated. 16 refs, 18 tabs, 4 figs

Concentration of radionuclides by marine organisms

International Nuclear Information System (INIS)

Nakamura, Ryoichi

1995-01-01

The Japanese, who have ever been confronted with atomic bombs, are said to be very sensitive to the nuclear power, radioactivity and so on. However, the peaceful uses of the nuclear power are closely related to our daily lives. Consequently, we should recognize correctly the nuclear power, radioactivity and so on, without refusing emotion-ally or admitting uncritically. Many marine organisms have abilities to accumulate radionuclides to very high concentrations. But, the levels of man-made radioactivity of marine organisms in the sea around Japan have been decreased in recent years compared with those in the past. So, the annual internal dose equivalent for Japanese from seafood (marine organisms) are originated mainly from the natural radionuclides like 210 Po, 210 Pb and 40 K. Nevertheless, study on the marine radioecology must be progressed against the inadvertent radioactive contamination of the surrounding sea, due to the increase of nuclear facilities and nuclear weapons. (author)

Cluster analysis of radionuclide concentrations in beach sand

NARCIS (Netherlands)

de Meijer, R.J.; James, I.; Jennings, P.J.; Keoyers, J.E.

This paper presents a method in which natural radionuclide concentrations of beach sand minerals are traced along a stretch of coast by cluster analysis. This analysis yields two groups of mineral deposit with different origins. The method deviates from standard methods of following dispersal of

Leaching of radionuclides from decaying blueberry leaves: Relative rate independent of concentration

Energy Technology Data Exchange (ETDEWEB)

Sheppard, S.C.; Evenden, W.G. (Atomic Energy of Canada Ltd., Pinawa, Manitoba (Canada))

Leaching of radionuclides from decaying vegetation has not been extensively investigated, especially for radionuclides other than {sup 137}Cs. The authors obtained leaves of blueberry (Vaccinium angustifolium {times} V. corymbosum) that contained over 25-fold ranges in Se, Cs, and I concentrations, as well as a small quantity of leaves containing detectable U. All were contaminated by way of root uptake. Leaching took place for a period of 1 yr in the laboratory, using leach water from forest litter. Monthly, measurements were made of the radionuclide contents and decaying leaf dry weights. The data conformed to an exponential decay model with two first-order components. In no case did the relative loss rates vary systematically with the initial tissue radionuclide concentrations. Loss rates decreased in the order Cs > I > U > dry wt. > Se. Because of the low leaching rate of Se relative to the loss of dry weight, decaying litter may actually accumulate elements such as Se. Accumulation of radionuclides in litter could have important implications for lateral transport, recycling, and direct incorporation into edible mushrooms.

Leaching of radionuclides from decaying blueberry leaves: Relative rate independent of concentration

International Nuclear Information System (INIS)

Sheppard, S.C.; Evenden, W.G.

1990-01-01

Leaching of radionuclides from decaying vegetation has not been extensively investigated, especially for radionuclides other than 137 Cs. The authors obtained leaves of blueberry (Vaccinium angustifolium x V. corymbosum) that contained over 25-fold ranges in Se, Cs, and I concentrations, as well as a small quantity of leaves containing detectable U. All were contaminated by way of root uptake. Leaching took place for a period of 1 yr in the laboratory, using leach water from forest litter. Monthly, measurements were made of the radionuclide contents and decaying leaf dry weights. The data conformed to an exponential decay model with two first-order components. In no case did the relative loss rates vary systematically with the initial tissue radionuclide concentrations. Loss rates decreased in the order Cs > I > U > dry wt. > Se. Because of the low leaching rate of Se relative to the loss of dry weight, decaying litter may actually accumulate elements such as Se. Accumulation of radionuclides in litter could have important implications for lateral transport, recycling, and direct incorporation into edible mushrooms

An international database of radionuclide concentration ratios for wildlife: development and uses

International Nuclear Information System (INIS)

Copplestone, D.; Beresford, N.A.; Brown, J.E.; Yankovich, T.

2013-01-01

A key element of most systems for assessing the impact of radionuclides on the environment is a means to estimate the transfer of radionuclides to organisms. To facilitate this, an international wildlife transfer database has been developed to provide an online, searchable compilation of transfer parameters in the form of equilibrium-based whole-organism to media concentration ratios. This paper describes the derivation of the wildlife transfer database, the key data sources it contains and highlights the applications for the data. -- Highlights: • An online database containing wildlife radionuclide transfer parameters is described. • Database underpins recent ICRP and IAEA data wildlife transfer compilations. • Database contains equilibrium based whole organism to media concentration ratios

Radionuclide concentrations in benthic invertebrates from Amchitka and Kiska Islands in the Aleutian Chain, Alaska.

Science.gov (United States)

Burger, Joanna; Gochfeld, Michael; Jewett, Stephen C

2007-05-01

Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U) were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965-1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 +/- 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 +/- 0.804 Bq/kg) and 238U (0.730 +/- 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as 'shellfish', for comparative purposes in determining geographical patterns, understanding possible effects, and for

A Study on the Determination of Radionuclide Concentrations in Animal Feedstuffs for Use Following a Nuclear Emergency

International Nuclear Information System (INIS)

Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Choi, Young Gil; Han, Moon Hee

2001-01-01

The optimized derived intervention levels for animal products were evaluated based on cost-benefit analysis. From these results, the radionuclide concentrations in animal feedstuffs for use were derived. It was shown that radionuclide concentrations in animal feedstuffs for use depend strongly on animal products, radionuclides and feeding period (period from the starting time to be fed with contaminated feedstuffs to production time of animal products). In case of feedstuffs contaminated with long-lived radionuclides ( 137 Cs, 90 Sr), the feedstuffs with lower contamination should be supplied to animals with increase of feeding period due to the bioaccumulation of radionuclides. While, in case of feedstuffs contaminated with short-lived radionuclides ( 131 I), the feeding of higher contaminated feedstuffs was possible with increase of feeding period due to radionuclide decay. It was shown that 137 Cs concentration in animal feedstuffs for use was lower than 90 Sr concentration. It is primarily due to the higher feed-animal product transfer factor of 137 Cs

Radionuclide Concentrations in Terrestrial Vegetation and Soil Samples On and Around the Hanford Site, 1971 Through 2008

Energy Technology Data Exchange (ETDEWEB)

Simmons, Mary Ann; Poston, Ted M.; Fritz, Brad G.; Bisping, Lynn E.

2011-07-29

Environmental monitoring is conducted on the U.S. Department of Energy (DOE) Hanford Site to comply with DOE Orders and federal and state regulations. Major objectives of the monitoring are to characterize contaminant levels in the environment and to determine site contributions to the contaminant inventory. This report focuses on surface soil and perennial vegetation samples collected between 1971 and 2008 as part of the Pacific Northwest National Laboratory Surface Environmental Surveillance Project performed under contract to DOE. Areas sampled under this program are located on the Hanford Site but outside facility boundaries and on public lands surrounding the Hanford Site. Additional samples were collected during the past 8 years under DOE projects that evaluated parcels of land for radiological release. These data were included because the same sampling methodology and analytical laboratory were used for the projects. The spatial and temporal trends of six radionuclides collected over a 38-year period were evaluated. The radionuclides----cobalt-60, cesium-137, strontium-90, plutonium-238, plutonium-239/240, and uranium (reported either as uranium-238 or total uranium)----were selected because they persist in the environment and are still being monitored routinely and reported in Hanford Site environmental reports. All these radionuclides were associated with plutonium production and waste management of activities occurring on the site. Other sources include fallout from atmospheric testing of nuclear weapons, which ended in 1980, and the Chernobyl explosion in 1986. Uranium is also a natural component of the soil. This assessment of soil and vegetation data provides important information on the distribution of radionuclides in areas adjacent to industrial areas, established perimeter locations and buffer areas, and more offsite nearby and distant locations. The concentrations reflect a tendency for detection of some radionuclides close to where they were

SLUDGE BATCH 5 ACCEPTANCE EVALUATION RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB5 QUALIFICATION SAMPLE PREPARED AT SRNL

International Nuclear Information System (INIS)

Bannochie, C; Ned Bibler, N; David Diprete, D

2008-01-01

transferred to SRNL for measurement of these radionuclides. Data presented in this report represents the measured or estimated radionuclide concentrations obtained from several standard and special analytical methods performed by Analytical Development (AD) personnel within SRNL. The method for I-129 measurement in sludge is described in detail. Most of these methods were performed on solutions resulting from the dissolutions of the slurry samples. Concentrations are given for twenty-nine radionuclides along with total alpha and beta activity. Values for total gamma and total gamma plus beta activities are also calculated. Results also indicate that 98% of the Tc-99 and 92% of the I-129 that could have been in this sludge batch have been removed by chemical processing steps in the SRS Canyons or Tank Farm

Radionuclide concentration in ground-level air from 1986 to 1987 in North Germany and North Norway

International Nuclear Information System (INIS)

Kolb, W.

1988-03-01

The activity concentration of various fission products and some other radionuclides (e.g. Be-7, Na-22, K-40 and Pb-210) contained in surface air were determined by γ-spectroscopy. The mean monthly acitvity concentrations of up to 30 radionuclides measured in 1986 and 1987 in Brunswick, Berlin and Skibotn (North Norway) are tabulated. The Chernobyl accident of April 26, 1986, resulted in 1986 in an annual mean Cs-137 activity concentration of 2.4 mBq/m 3 in Brunswick, 8.8 mBq/m 3 in Berlin and 0.3 mBq/m 3 at Skibotn. In 1987 the Cs-137 concentrations were just about 1% of these values. Occasionally fresh fission products from other sources were detected as e.g. I-131 in March 1987 (very likely released from a reactor site in Ukraine) and in August 1987 (released from an underground nuclear test on Novaja Zemlya together with other short-lived fission products). The effective dose equivalent due to inhalation of fission products is estimated for all three sites and compared with the Pb-210 inhalation dose. (orig./HP) [de

Protein concentrate production from the biomass contaminated with radionuclides

International Nuclear Information System (INIS)

Nizhko, V.F.; Shinkarenko, M.P.; Polozhaj, V.V.; Krivchik, O.V.

1992-01-01

Coefficients of radionuclides accumulation are determined for traditional and rare forage crops grown on contaminated soils. It is shown that with low concentration of radionuclides in soil minimal level of contamination were found in the biomass of lupine (Lupinus luteus L.) and sainfoin (Onobrychis hybridus L.). Relatively high levels of contamination were found in comfrey (Symphytum asperum Lepech.) and bistort (Polygonum divaricatum L.). Comparatively low accumulation coefficients in case of higher density of soil contamination were observed for white and yellow sweetclovers (Melilotus albus Medik. and M. officinalis (L.) Desr.), while higher values of coefficients were found for bird's-foot trefoil (Lotus corniculatus L.), white clover (Trifolium repens L.) and alsike clover (t. hybridum L.). Biomass of white sweet-clover and alsike clover has been processed to produce leaf protein concentrate. It is shown that with biomass contamination of 1 kBq/kg and above conventional technology based on thermal precipitation of the protein does not provide production of pure product. More purified protein concentrates are obtained after two-stage processing of the biomass

Airborne remote sensing of estuarine intertidal radionuclide concentrations

International Nuclear Information System (INIS)

Rainey, M.P.

1999-08-01

The ability to map industrial discharges through remote sensing provides a powerful tool in environmental monitoring. Radionuclide effluents have been discharged, under authorization, into the Irish Sea from BNFL (British Nuclear Fuels Pic.) sites at Sellafield and Springfields since 1952. The quantitative mapping of this anthropogenic radioactivity in estuarine intertidal zones is crucial for absolute interpretations of radionuclide transport. The spatial resolutions of traditional approaches e.g. point sampling and airborne gamma surveys are insufficient to support geomorphic interpretations of the fate of radionuclides in estuaries. The research presented in this thesis develops the use of airborne remote sensing to derive high-resolution synoptic data on the distribution of anthropogenic radionuclides in the intertidal areas of the Ribble Estuary, Lancashire, UK. From multidate surface sediment samples a significant relationship was identified between the Sellafield-derived 137 Cs and 241 Am and clay content (r 2 = 0.93 and 0.84 respectively). Detailed in situ, and laboratory, reflectance (0.4-2.5μm) experiments demonstrated that significant relationships exist between Airborne Thematic Mapper (ATM) simulated reflectance and intertidal sediment grain-size. The spectral influence of moisture on the reflectance characteristics of the intertidal area is also evident. This had substantial implications for the timing of airborne image acquisition. Low-tide Daedalus ATM imagery (Natural Environmental Research Council) was collected of the Ribble Estuary on May 30th 1997. Preprocessing and linear unmixing of the imagery allowed accurate sub-pixel determinations of sediment clay content distributions (r 2 = 0.81). Subsequently, the established relationships between 137 Cs and 241 Am and sediment grain-size enabled the radionuclide activity distributions across the entire intertidal area (92 km 2 ) to be mapped at a geomorphic scale (1.75 m). The accuracy of these maps

The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 2. Radionuclide concentrations measured in the aquatic environment of the atolls

International Nuclear Information System (INIS)

1998-08-01

A marine monitoring programme was carried out within the framework of the IAEA's project entitled ''Study of the Radiological Situation at Mururoa and Fangataufa Atolls'' with the aim of assessing present radionuclide concentrations in the marine environment of Mururoa and Fangataufa Atolls. The terms of reference of the marine working group (WG2) included a review of the data provided by the French authorities on radionuclide distributions in the littoral and sub-littoral environments at the atolls. Further, using accredited international laboratories, it was decided to carry out sufficient and new independent monitoring work at and around the atolls in order to validate existing French data and, the same time, to provide a representative and high quality data set on current radionuclide concentrations in the marine environment, with particular reference to the requirement of Task Group A for radiological assessment purposes. This work included measurements of the current radionuclide concentrations in the marine environment, and estimation of concentration factors and K d values appropriate for the region. The variations in activity concentrations in the lagoons over the past few years are discussed, and the likely sources of activity implied by these data are identified where possible

The Concentration Levels Of Some Isotopic Radionuclides In The Coastal Sediments Of The Red Sea, Egypt

International Nuclear Information System (INIS)

EL SAHARTY, A.A.; DAR, M.A.

2010-01-01

The radionuclide activities of 238 U, 232 Th, 40 K and 137 Cs were measured using high resolution gamma spectrometry system. The total organic matter (TOM) and carbonate contents were also measured in the surface sediments of three valleys downstream at the southern Egyptian Red Sea coast. These localities are characterized by the presence of mangrove swamps with dense aerobic roots that provide calm conditions for particulate and fine sediments settlement. 238 U and 232 Th recorded almost equal activity values in the studied localities and their occurrence in the localities indicated that the metal accumulation are due to the complex and multiple processes that characterize the mangrove environments including accumulation in particulate form with the fine sediments, absorption on iron and manganese oxides and hydroxides from the sea water, incorporation inside the carbonate frameworks and as detrital phase. 40 K showed obvious radioactivity in the three localities indicating the presence of terrestrial radionuclide. 137 Cs concentrations were not evident in the studied localities which may indicate non-significant artificial source of radionuclide activity.

Radioactivity in papers: the concentration and source of naturally occurring radionuclides

International Nuclear Information System (INIS)

Kobashi, Asaya

2005-01-01

The radioactivities of naturally occurring radionuclides ( 226 Ra, 228 Ra, 228 Th and 40 K) in papers such as magazines, newspapers, and copying papers produced in Japan were determined by gamma-ray spectrometry to obtain information on radioactivity level of papers. The X-ray diffraction measurement of the samples was also carried out to elucidate the source of radionuclides contained in them. The average 226 Ra, 228 Ra, 228 Th, and 40 K contents of pocket-sized books were 6.4, 21.5, 23.7, and 18.8 Bq kg -1 , respectively, and those of other kinds of samples were near to or less than the values. The 228 Th content was generally somewhat higher than the 228 Ra content. Possibly 228 Ra was leached from the raw materials of the papers to water during their production in preference to 228 Th. The concentrations of the naturally occurring radionuclides were correlated to each other. The X-ray diffraction study showed that kaolinite, talc, and calcite were contained in the papers. The kaolinite content of the samples was correlated to the concentrations of the naturally occurring radionuclides, indicating that the naturally occurring radionuclides in the paper samples were mainly brought with kaolinite used as filler or coating pigment in the papers. The regression analysis of the data showed that the natural radioactivity content of filler kaolinite was higher than that of pigment kaolinite. (author)

Radionuclide concentrations in vegetation at the Los Alamos National Laboratory in 1998

International Nuclear Information System (INIS)

Gonzales, G.J.; Fresquez, P.R.; Mullen, M.A.; Naranjo, L. Jr.

2000-01-01

This report summarizes and evaluates the concentrations of 3 H, 137 Cs, 238 Pu, 239,240 Pu, 241 Am, 90 Sr, and total U in understory and overstory vegetation collected from Los Alamos National Laboratory (LANL), its perimeter, and regional background areas in 1998. Comparisons to conservative toxicity reference value safe limits were also made. The arithmetic mean LANL radionuclide concentrations in understory were 501 pCi L -1 for 3 H, 0.581 pCi ash g -1 for 137 Cs, 0.001 pCi ash g -1 for 238 Pu, 0.008 pCi ash g -1 for 239,240 Pu, 0.007 pCi ash g -1 for 241 Am, 1.46 pCi ash g -1 for 90 Sr, and 0.233 microg ash g -1 for total uranium. The mean LANL radionuclide concentrations in overstory were 463 pCi L -1 for 3 H, 1.51 pCi ash g -1 for 137 Cs, 0.0004 pCi ash g -1 238 Pu, 0.008 pCi ash g -1 for 239,240 Pu, 0.014 pCi ash g -1 for 241 Am, 1.97 pCi ash g -1 for 90 Sr, and 0.388 microg ash g -1 for total uranium. Concentrations of radionuclides and total U in both understory and overstory vegetation at LANL generally were not statistically higher than in perimeter and regional background vegetation (α = 0.05). The exceptions were LANL 3 H > perimeter 3 H (understory) and LANL 3 H background 3 H (overstory). All maximum radionuclide concentrations were lower than toxicity reference values. With the exception of total U, the relationship between contaminant concentration in soil vs. vegetation was insignificant (α = 0.05). Generally, as the concentration of total U in soil decreased, the concentration in vegetation increased. This held true for both understory and overstory and regardless of whether data were separated by general location (LANL, perimeter, and background) or not. There was no apparent relationship between contaminant concentrations in understory vs. overstory

Measurement of the terrestrial and anthropogenic radionuclide concentrations in Bafra Kizilirmak delta (bird sanctuary) in Turkey

International Nuclear Information System (INIS)

Mutuk, H.; Guemues, H.; Turhan, S.

2014-01-01

In this study, the activity concentrations of terrestrial and anthropogenic radionuclides in the soil samples collected from Bafra Kizilirmak Delta were measured by using gamma spectrometry with an NaI(Tl) detector. The average values of activity concentrations of 238 U, 232 Th and 40 K were found to be 37.2±2.8, 33.7±3.1 and 413.0±59.8 Bq kg -1 , respectively. 137 Cs was also measured in some samples. It has a mean value of 13.8±1.0 Bq kg -1 . From the activity concentrations, the absorbed gamma dose rates in outdoor and the corresponding annual effective dose rates and external hazard index (Hex) were estimated. (authors)

Studies on concentration of radionuclides by marine organisms

International Nuclear Information System (INIS)

Anon.

1974-01-01

Materials used were more than 20 kinds of fishes. 85 Sr chiefly localized in the hard tissue, such as the scale, bone, and gill, 60 Co in the liver, 65 Zn in the digestive organs, such as the liver, stomach, and intestine, 144 Ce in the gill, scale and liver, 106 Ru in the liver and intestine, and 131 I in the digestive organs, especially in the gallbladder. However, all these nuclides showed only slight localization in the edible parts of fish bodies. The concentration of radionuclides in immature anchovy was examined using 85 Sr, 137 Cs, 144 Ce and so on, as tracers. The concentration factor of 137 Cs was 10 times that of 85 Sr, though, the loss of 137 Cs was very rapid compared to that of 85 Sr. 144 Ce pollution of immature anchovy was chiefly by adsorption to the surface of fish bodies. As to shells radionuclides were remarkably taken up in the mid-gut gland, among them, 144 Ce taken up in shell bodies was not excreated but accumulated in the bodies. In algae, 85 Sr, 106 Ru, and 59 Fe seemed to pollute algae physico-chemically by adsorption, and 131 I, 137 Cs, and 60 Co seemed to be taken up through inorganic metabolism showing their concentration factor 100 times that in fishes. (JPN)

Radionuclide concentrations in bird tissues, their foods and feeding areas near Ravenglass

International Nuclear Information System (INIS)

Lowe, V.P.W.

1987-08-01

Since 1983, concern has been expressed about an apparent decline in the numbers of waterfowl, waders and gulls in the Ravenglass estuary, particularly of the black-headed gulls nesting on the Drigg dunes; it was suggested this might be due to the radionuclide concentrations in their diet and general environment. Oystercatchers and shelduck had some of the highest concentrations of Cs-137 in their tissues, yet their breeding and numbers remained unaffected. Calculations of the total dose equivalent to the whole body of gulls spending 4 months in the estuary before laying eggs, amounted to 2.8 mSv (≅ 2.4 m Gy), and to the gut lining 40.3 mSv. As a minimum chronic dose of 1000 m Gy d -1 has been found to be necessary to retard the growth of chicks or cause 50% mortality among gull chick embryos before full development, radionuclide concentrations at Ravenglass were at least three orders of magnitude too low to have any effect. 12 species of marine invertebrates were also analysed, but no evidence was found that radionuclides from Sellafield were being accumulated in any species to the point where concentrations were of potential importance to birds feeding on them. (author)

Tissue radionuclide concentrations in water birds and upland birds on the Hanford Site (USA) from 1971-2009

International Nuclear Information System (INIS)

Delistraty, Damon; Van Verst, Scott

2011-01-01

Historical operations at the Hanford Site (Washington State, USA) have released a wide array of non-radionuclide and radionuclide contaminants into the environment. As a result, there is a need to characterize contaminant effects on site biota. Within this framework, the main purpose of our study was to evaluate radionuclide concentrations in bird tissue, obtained from the Hanford Environmental Information System (HEIS). The database was sorted by avian group (water bird vs. upland bird), radionuclide (over 20 analytes), tissue (muscle, bone, liver), location (onsite vs. offsite), and time period (1971-1990 vs. 1991-2009). Onsite median concentrations in water birds were significantly higher (Bonferroni P < 0.05) than those in onsite upland birds for Cs-137 in muscle (1971-1990) and Sr-90 in bone (1991-2009), perhaps due to behavioral, habitat, or trophic species differences. Onsite median concentrations in water birds were higher (borderline significance with Bonferroni P = 0.05) than those in offsite birds for Cs-137 in muscle (1971-1990). Onsite median concentrations in the earlier time period were significantly higher (Bonferroni P < 0.05) than those in the later time period for Co-60, Cs-137, Eu-152, and Sr-90 in water bird muscle and for Cs-137 in upland bird muscle tissue. Median concentrations of Sr-90 in bone were significantly higher (Bonferroni P < 0.05) than those in muscle for both avian groups and both locations. Over the time period, 1971-2009, onsite median internal dose was estimated for each radionuclide in water bird and upland bird tissues. However, a meaningful dose comparison between bird groups was not possible, due to a dissimilar radionuclide inventory, mismatch of time periods for input radionuclides, and lack of an external dose estimate. Despite these limitations, our results contribute toward ongoing efforts to characterize ecological risk at the Hanford Site. - Highlights: → Radionuclides evaluated in bird tissues on the Hanford Site

Tissue radionuclide concentrations in water birds and upland birds on the Hanford Site (USA) from 1971-2009

Energy Technology Data Exchange (ETDEWEB)

Delistraty, Damon, E-mail: DDEL461@ecy.wa.gov [Washington State Department of Ecology, N. 4601 Monroe Street, Spokane, WA 99205-1295 (United States); Van Verst, Scott [Washington State Department of Health, Olympia, WA (United States)

2011-08-15

Historical operations at the Hanford Site (Washington State, USA) have released a wide array of non-radionuclide and radionuclide contaminants into the environment. As a result, there is a need to characterize contaminant effects on site biota. Within this framework, the main purpose of our study was to evaluate radionuclide concentrations in bird tissue, obtained from the Hanford Environmental Information System (HEIS). The database was sorted by avian group (water bird vs. upland bird), radionuclide (over 20 analytes), tissue (muscle, bone, liver), location (onsite vs. offsite), and time period (1971-1990 vs. 1991-2009). Onsite median concentrations in water birds were significantly higher (Bonferroni P < 0.05) than those in onsite upland birds for Cs-137 in muscle (1971-1990) and Sr-90 in bone (1991-2009), perhaps due to behavioral, habitat, or trophic species differences. Onsite median concentrations in water birds were higher (borderline significance with Bonferroni P = 0.05) than those in offsite birds for Cs-137 in muscle (1971-1990). Onsite median concentrations in the earlier time period were significantly higher (Bonferroni P < 0.05) than those in the later time period for Co-60, Cs-137, Eu-152, and Sr-90 in water bird muscle and for Cs-137 in upland bird muscle tissue. Median concentrations of Sr-90 in bone were significantly higher (Bonferroni P < 0.05) than those in muscle for both avian groups and both locations. Over the time period, 1971-2009, onsite median internal dose was estimated for each radionuclide in water bird and upland bird tissues. However, a meaningful dose comparison between bird groups was not possible, due to a dissimilar radionuclide inventory, mismatch of time periods for input radionuclides, and lack of an external dose estimate. Despite these limitations, our results contribute toward ongoing efforts to characterize ecological risk at the Hanford Site. - Highlights: > Radionuclides evaluated in bird tissues on the Hanford Site

Investigations of 90 SR activity concentrations in animal bones in Croatia

Energy Technology Data Exchange (ETDEWEB)

Maracic, M.; Franic, Z.; Marovic, G. [Institute for Medical Research and Occupational Health, Zagreb (Croatia)

2006-07-01

The paper describes investigations of 90 Sr activity concentrations in long bones of some domestic animals (cows, pigs and lambs) collected over the last ten years in the Republic of Croatia. These investigations are a part of an extended and still ongoing monitoring programme of radioactive contamination of human environment in Croatia. Bone is a critical organ for the accumulation of many radionuclides, including 90 Sr, a highly toxic radionuclide, similar to calcium in its chemicalaviour and metabolic processes. It has been found that the 90 Sr activity concentrations in bones differ between respective animal species, the highest activity concentrations being found in lamb bones. As the decrease of activity concentrations can be generally described by the exponential function, by fitting the measured data to the theoretical curve was estimated the ecological half-life of 90 Sr in bones of respective species. In addition was investigated the relation between 90 Sr activity concentrations in bones and fallout. The transient increases and decreases in 90 Sr activity concentrations in bones can be partially explained by a variety of environmental physical factors that naturally fluctuate. (authors)

Investigations of 90 SR activity concentrations in animal bones in Croatia

International Nuclear Information System (INIS)

Maracic, M.; Franic, Z.; Marovic, G.

2006-01-01

The paper describes investigations of 90 Sr activity concentrations in long bones of some domestic animals (cows, pigs and lambs) collected over the last ten years in the Republic of Croatia. These investigations are a part of an extended and still ongoing monitoring programme of radioactive contamination of human environment in Croatia. Bone is a critical organ for the accumulation of many radionuclides, including 90 Sr, a highly toxic radionuclide, similar to calcium in its chemical behaviour and metabolic processes. It has been found that the 90 Sr activity concentrations in bones differ between respective animal species, the highest activity concentrations being found in lamb bones. As the decrease of activity concentrations can be generally described by the exponential function, by fitting the measured data to the theoretical curve was estimated the ecological half-life of 90 Sr in bones of respective species. In addition was investigated the relation between 90 Sr activity concentrations in bones and fallout. The transient increases and decreases in 90 Sr activity concentrations in bones can be partially explained by a variety of environmental physical factors that naturally fluctuate. (authors)

Concentration parameters for radionuclides by marine molluscs

International Nuclear Information System (INIS)

Nakahara, Motokazu; Makamura, Ryoichi; Suzuki, Yuzuru; Matsuba, Mitsue

1994-01-01

Accumulation of radionuclides from seawater and from food by marine molluscs was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were 57 Co, 95m Tc, 103 Ru, 137 Cs, 65 Zn and 54 Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into nonradioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone (Haliotis discus) were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except 137 Cs and 54 Mn. Retention of 137 Cs and 54 Mn in the organisms one day after feeding of radioactive food was lower than 25% of the radioactivity dosed. (author)

Measurement of the terrestrial and anthropogenic radionuclide concentrations in Bafra Kizilirmak delta (bird sanctuary) in Turkey.

Science.gov (United States)

Mutuk, Halil; Gümüs, Hasan; Turhan, Seref

2014-01-01

In this study, the activity concentrations of terrestrial and anthropogenic radionuclides in the soil samples collected from Bafra Kızılırmak Delta were measured by using gamma spectrometry with an NaI(Tl) detector. The average values of activity concentrations of (238)U, (232)Th and (40)K were found to be 37.2±2.8, 33.7±3.1 and 413.0±59.8 Bq kg(-1), respectively. (137)Cs was also measured in some samples. It has a mean value of 13.8±1.0 Bq kg(-1). From the activity concentrations, the absorbed gamma dose rates in outdoor and the corresponding annual effective dose rates and external hazard index (Hex) were estimated.

Factors affecting 210Po and 210Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes

International Nuclear Information System (INIS)

Carvalho, Fernando P.; Oliveira, Joao M.; Alberto, G.

2011-01-01

The activity of 210 Po and 210 Pb was determined in mussels of the same size (3.5-4.0 cm shell length) sampled monthly over a 17-month period at the Atlantic coast of Portugal. Average radionuclide concentration values in mussels were 759 ± 277 Bq kg -1 for 210 Po (range 460-1470 Bq kg -1 dry weight), and 45 ± 19 Bq kg -1 for 210 Pb (range 23-96 Bq kg -1 dry weight). Environmental parameters and mussel biometric parameters were monitored during the same period. Although there was no seasonal variation of radionuclide concentrations in sea water during the study period, the concentration of radionuclide activity in mussels varied seasonally displaying peaks of high concentrations in winter and low concentrations in summer. Analysis of radionuclide data in relation to the physiological Condition Index of mussels revealed that 210 Po and 210 Pb activities in the mussel (average activity per individual) remained nearly constant during the investigation period, while mussel body weight fluctuated due to fat storage/expenditure in the soft tissues. Similar variation of radionuclide concentrations was observed in mussels transplanted from the sea coast into the Tejo Estuary. However, under estuarine environmental conditions and with higher food availability throughout the year, transplanted mussel Condition Index was higher than in coastal mussels and average radionuclide concentrations were 210 ± 75 Bq kg -1 (dry weight) for 210 Po and 10 ± 4 Bq kg -1 (dry weight) for 210 Pb, therefore lower than in coastal mussels with similar shell length. It is concluded that the apparent seasonal fluctuation and inter-site difference of radionuclide concentrations were mostly caused by mussel body weight fluctuation and not by radionuclide body burden fluctuation. This interpretation can be extended to the apparent seasonal fluctuation in concentrations of lipophilic and lipophobic contaminants in mussels, and provides an explanation for occasional high concentrations of 210 Po

FOOD II: an interactive code for calculating concentrations of radionuclides in food products

International Nuclear Information System (INIS)

Zach, R.

1978-11-01

An interactive code, FOOD II, has been written in FORTRAN IV for the PDP 10 to allow calculation of concentrations of radionuclides in food products and internal doses to man under chronic release conditions. FOOD II uses models unchanged from a previous code, FOOD, developed at Battelle, Pacific Northwest Laboratories. The new code has different input and output features than FOOD and a number of options have been added to increase flexibility. Data files have also been updated. FOOD II takes into account contamination of vegetation by air and irrigation water containing radionuclides. Contamination can occur simultaneously by air and water. Both direct deposition of radionuclides on leaves, and their uptake from soil are possible. Also, animals may be contaminated by ingestion of vegetation and drinking water containing radionuclides. At present, FOOD II provides selection of 14 food types, 13 diets and numerous radionuclides. Provisions have been made to expand all of these categories. Six additional contaminated food products can also be entered directly into the dose model. Doses may be calculated for the total body and six internal organs. Summaries of concentrations in food products and internal doses to man can be displayed at a local terminal or at an auxiliary high-speed printer. (author)

Correlations between Natural Radionuclide Concentrations in Soil and Vine-Growth Potential

International Nuclear Information System (INIS)

Modisane, T.G.D.

2008-01-01

Stellenbosch district is known as one of the best wine-producing regions in South Africa and lies 45 km east of Cape Town. It has a large number of estates, of which one of them was earmarked for vineyard development and is of much importance to this study. Soil plays an important role in the development of the vine and ultimately the grapes harvested from the vine. It is therefore important to characterise vineyard soils (quantitatively and qualitatively) and to study the impact of soil properties on the vine. These properties include among others and of importance to this study, the soil ph, concentrations of trace elements, clay content and natural radioactivity concentrations (1). In this study correlations between radiometric data and traditional chemical data in vineyard soils used to infer growth potential were studied. Discussed below are experimental techniques used in the determination of activity concentration of natural radionuclide ( 40 K, 232 Th and 238 U) in soil, data analysis, results and conclusions

Activity concentration and population dose from natural occurring radionuclide (40K) due to consumption of fresh water fish

International Nuclear Information System (INIS)

Jha, M.K.; Patra, A.K.; Jaison, T.J.; Ravi, P.M.; Tripathi, R.M.

2015-01-01

The objective of this study was to measure the concentration of natural occurring radionuclide ( 40 K) in different fresh water fish collected from Moticher lake near Kakrapar, Gujarat. The three types of commonly available fresh water fish in Moticher lake are Notopterus sps, Ophiocephalus sps. and Tor sps. The 40 K activity (Bq/kg flesh wt.) was found to be in the range of 38-100 (Notopterus sps.), 33-123 (Ophiocephalus sps.) and 80-116 (Tor sps.) respectively. The ingestion dose (μSv/y) to the adult population around Kakrapar was estimated due to the consumption of fresh water fish and found to be in the range of 7.7-20.5 (Notopterus sps.), 6.8-25.0 (Ophiocephalus sps.) and 16.0-24.0 (Tor sps.) respectively. (author)

Radionuclides in ground-level air

International Nuclear Information System (INIS)

Sinkko, K.

1987-01-01

In the air surveillance programme the concentrations of artificial radionuclides are monitored in the air close to the ground to obtain the necessary basic data for estimating the exposure of the Finnish population to fall-out radionuclides and also to detect atmospheric traces of radioactive materials caused by their use or production. Airborne dust is collected on filters with high-volume air samplers and the concentrations of gamma-emitting radionuclides in the air are evaluated. In the first quarter of 1986 only long-lived cesium, caused by earlier atmospheric nuclear explosions was detected. The concentrations of cesium were very low. In January and March a small amount of short-lived, fresh fission and activation products were also observed

Concentration parameters for radionuclides by marine molluscs

Energy Technology Data Exchange (ETDEWEB)

Nakahara, Motokazu; Makamura, Ryoichi; Suzuki, Yuzuru; Matsuba, Mitsue [National Inst. of Radiological Sciences, Nakaminato, Ibaraki (Japan). Nakaminato Lab. Branch Office

1994-03-01

Accumulation of radionuclides from seawater and from food by marine molluscs was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were {sup 57}Co, {sup 95m}Tc, {sup 103}Ru, {sup 137}Cs, {sup 65}Zn and {sup 54}Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into nonradioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone (Haliotis discus) were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except {sup 137}Cs and {sup 54}Mn. Retention of {sup 137}Cs and {sup 54}Mn in the organisms one day after feeding of radioactive food was lower than 25% of the radioactivity dosed. (author).

Elevated concentrations of naturally occurring radionuclides in heavy mineral-rich beach sands of Langkawi Island, Malaysia.

Science.gov (United States)

Khandaker, Mayeen Uddin; Asaduzzaman, Khandoker; Sulaiman, Abdullah Fadil Bin; Bradley, D A; Isinkaye, Matthew Omoniyi

2018-02-01

Study is made of the radioactivity in the beach sands of Langkawi island, a well-known tourist destination. Investigation is made of the relative presence of the naturally occurring radionuclide 40 K and the natural-series indicator radionuclides 226 Ra and 232 Th, the gamma radiation exposure also being estimated. Sample quantities of black and white sand were collected for gamma ray spectrometry, yielding activity concentration in black sands of 226 Ra, 232 Th and 40 K from 451±9 to 2411±65Bqkg -1 (mean of 1478Bqkg -1 ); 232±4 to 1272±35Bqkg -1 (mean of 718Bqkg -1 ) and 61±6 to 136±7Bqkg -1 (mean of 103Bqkg -1 ) respectively. Conversely, in white sands the respective values for 226 Ra and 232 Th were appreciably lower, at 8.3±0.5 to 13.7±1.4Bqkg -1 (mean of 9.8Bqkg -1 ) and 4.5±0.7 to 9.4±1.0Bqkg -1 (mean of 5.9Bqkg -1 ); 40 K activities differed insubstantially from that in black sands, at 85±4 to 133±7Bqkg -1 with a mean of 102Bqkg -1 . The mean activity concentrations of 226 Ra and 232 Th in black sands are comparable with that of high background areas elsewhere in the world. The heavy minerals content gives rise to elevated 226 Ra and 232 Th activity concentrations in all of black sand samples. Evaluation of the various radiological risk parameters points to values which in some cases could be in excess of recommendations providing for safe living and working. Statistical analysis examines correlations between the origins of the radionuclides, also identifying and classifying the radiological parameters. Present results may help to form an interest in rare-earth resources for the electronics industry, power generation and the viability of nuclear fuels cycle resources. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trends in radionuclide concentrations for wildlife and food products near Hanford for the period 1971-1988

International Nuclear Information System (INIS)

Cadwell, L.L.; Eberhardt, L.E.; Price, K.R.; Carlile, D.W.

1990-01-01

We evaluated the Hanford environmental data base for trends in radionuclide concentrations in wildlife and food products sampled from 1971 through 1988 on or near the U.S. Department of Energy's Hanford Site in southeastern Washington. Although statistical analyses showed short-term changes, no upward trends in radionuclide concentrations were detected. Many samples showed a significant decline in some radionuclides, particularly for 137 Cs. Concentrations of 65 Zn also showed a downward trend in many samples. Cessation of atmospheric testing by the United States and the USSR in 1971 contributed to the decline in radionuclide levels in some samples. Contaminants discharged to the Columbia River at Hanford were reduced after shutdown of the last once-through cooling-water reactor in 1971. A decline in concentrations of 65 Zn in oysters from Willapa Bay and 60 Co and 65 Zn in mountain whitefish from the Hanford Reach of the Columbia River are attributable to reactor closure. There was also an apparent reduction in availability of radiological contamination to Hanford wildlife after decommissioning of waste-water disposal ponds and remediation of contaminated terrestrial sites

Effects of water treatment processes used at waterworks on natural radionuclide concentrations

International Nuclear Information System (INIS)

Haemaelaeinen, K.; Vesterbacka, P.; Maekelaeinen, I.; Arvela, H.

2004-08-01

The occurrence of uranium and other natural radionuclides in waters of waterworks and the effects of the conventional water treatment processes on radionuclide concentrations were investigated. Water samples were collected from 17 waterworks. Radionuclide concentrations of the collected samples were compared to the currently valid concentrations according to the Finnish regulation, ST guide 12.3. Similarly the measured concentrations were compared to the values presented in the 98/83/EC directive and in the Commission recommendation, 2001/928/Euratom. The guidelines based on chemical toxicity of uranium were also considered. This report presents a summary of the radionuclide concentrations in waters distributed by waterworks. Short-term and logn-term temporal variation of radionuclide levels in raw water were also investigated. Waterworks selected to this study used different kinds of raw water sources and a variety of water treatment processes. Water samples were collected from 46 water catchments which used groundwater in soil, artificial groundwater or groundwater in bedrock as a source of raw water. The most common water treatment used in these catchments was alkalization. Other treatment processes used were various types of filtrations (sand, anthracite, slow sand and membrane filtration) and aeration. Four of the catchments distributed water without treatment. Sampling was carried out in co-operation with local health inspectors and waterworks staff in spring 2002. Later that autumn, monitoring samples were collected from eight catchments. The maximum value for radon, presented in ST guide 12.3, was exceeded in three water catchments that used groundwater in bedrock as a source of raw water. No exceedings were found in those water catchments that use groundwater in soil or artificial groundwater. The limits of uranium and radium calculated from the total indicative dose (98/83/EC) were not exceeded but the guidelines for lead and polonium, given in the

Concentrations of radionuclides in reef and lagoon pelagic fish from the Marshall Islands

International Nuclear Information System (INIS)

Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Marsh, K.V.

1981-07-01

A radiological survey was conducted from September through November of 1978 to assess the concentrations of persistent man-made radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands of the Northern Marshall Islands. The atolls and islands include Rongelap, Utirik, Taka, Bikar, Rongerik, Ailinginae, Likiep, Jemo, Ailuk, Mejet, Wotho, Ujelang and Bikini. Over 4000 terrestrial and marine samples were collected for radionuclide analysis from 76 different islands. Soils, vegetation, indigenous animals, and cistern and groundwater were collected from the islands. Reef fish, pelagic species, clams, lagoon water, and sediments were obtained from the lagoons. A report is given of all available concentration data for 137 Cs, 90 Sr, /sup 239+240/Pu, 238 Pu, 241 Am as well as naturally occurring 40 K and other gamma emitting radionuclides in tissues and organs of different species of fish collected from the atolls

Determination of the activity concentration levels of the artificial radionuclide137Cs in soil samples collected from Qatar using high-resolution gamma-ray spectrometry

Science.gov (United States)

Al-Sulaiti, Huda; Nasir, Tabassum; Al Mugren, K. S.; Alkhomashi, N.; Al-Dahan, N.; Al-Dosari, M.; Bradley, D. A.; Bukhari, S.; Regan, P. H.; Santawamaitre, T.; Malain, D.; Habib, A.; Al-Dosari, Hanan; Daar, Eman

2016-09-01

The goal of this study was to establish the first baseline measurements for radioactivity concentration of the artificial radionuclide 137Cs in soil samples collected from the Qatarian peninsula. The work focused on the determination of the activity concentrations levels of man-made radiation in 129 soil samples collected across the landscape of the State of Qatar. All the samples were collected before the most recent accident in Japan, “the 2011 Fukushima Dai-ichi nuclear power plant accident”. The activity concentrations have been measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector situated in a low-background environment with a copper inner-plated passive lead shield. A radiological map showing the activity concentrations of 137Cs is presented in this work. The concentration wasfound to range from 0.21 to 15.41 Bq/kg. The highest activity concentration of 137Cs was observed in sample no. 26 in North of Qatar. The mean value was found to be around 2.15 ± 0.27 Bq/kg. These values lie within the expected range relative to the countries in the region. It is expected that this contamination is mainly due to the Chernobyl accident on 26 April 1986, but this conclusion cannot be confirmed because of the lack of data before this accident.

Concentration of radionuclides in uranium tailings and its uptake by plants at Jaduguda, Jharkhand, India

International Nuclear Information System (INIS)

Singh, Lal; Soni, Prafulla

2010-01-01

Mining and processing of uranium ore was started in several parts of eastern Singhbhum, viz. Jaduguda, Bhatin and Narwapahar (Jharkhand) in 1968. Radioactivity in the mine tailings has to be consolidated so that it does not emanate in the atmosphere or enter the food chain. Hence, the area has been covered with 30 cm thick soil cover followed by development of plant species that do not have any socioeconomic relevance in the area. Seven native plant species of forestry origin, viz. Colebrookea oppositifolia, Dodonaea viscosa, Furcraea foetida, Imperata cylindrica, Jatropha gossypifolia, Pogostemon benghalense and Saccharum spontaneum have been selected for experimental trials. Distribution and concentration of radionuclides have been evaluated in a tailing pond at different depths in soil and tailings. Radionuclide uptake in each of the selected plant species has been evaluated and discussed in this article. The highest concentration of radionuclides has been found in tailings > soil cover on tailings > roots of selected plant species > shoots of all the selected species. These results show that among the seven species tried, J. gossypifolia and F. foetida have the lowest uptake (below detectable limits), while S. spontaneum and P. benghalense have comparatively higher uptake. However, radionuclide concentration in all the tried species is significantly low compared to species of natural occurrence which have higher radionuclides uptake and accumulation. (author)

Concentration of radionuclides in uranium tailings and its uptake by plants at Jaduguda, Jharkhand, India

Energy Technology Data Exchange (ETDEWEB)

Singh, Lal; Soni, Prafulla [Ecology and Environment Div., Forest Research Institute, Dehradun (India)

2010-01-10

Mining and processing of uranium ore was started in several parts of eastern Singhbhum, viz. Jaduguda, Bhatin and Narwapahar (Jharkhand) in 1968. Radioactivity in the mine tailings has to be consolidated so that it does not emanate in the atmosphere or enter the food chain. Hence, the area has been covered with 30 cm thick soil cover followed by development of plant species that do not have any socioeconomic relevance in the area. Seven native plant species of forestry origin, viz. Colebrookea oppositifolia, Dodonaea viscosa, Furcraea foetida, Imperata cylindrica, Jatropha gossypifolia, Pogostemon benghalense and Saccharum spontaneum have been selected for experimental trials. Distribution and concentration of radionuclides have been evaluated in a tailing pond at different depths in soil and tailings. Radionuclide uptake in each of the selected plant species has been evaluated and discussed in this article. The highest concentration of radionuclides has been found in tailings > soil cover on tailings > roots of selected plant species > shoots of all the selected species. These results show that among the seven species tried, J. gossypifolia and F. foetida have the lowest uptake (below detectable limits), while S. spontaneum and P. benghalense have comparatively higher uptake. However, radionuclide concentration in all the tried species is significantly low compared to species of natural occurrence which have higher radionuclides uptake and accumulation. (author)

Factors affecting {sup 210}Po and {sup 210}Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Fernando P., E-mail: carvalho@itn.p [Nuclear and Technological Institute (ITN), Department of Radiological Protection and Nuclear Safety, E.N. 10, 2686-953 Sacavem (Portugal); Oliveira, Joao M.; Alberto, G. [Nuclear and Technological Institute (ITN), Department of Radiological Protection and Nuclear Safety, E.N. 10, 2686-953 Sacavem (Portugal)

2011-02-15

The activity of {sup 210}Po and {sup 210}Pb was determined in mussels of the same size (3.5-4.0 cm shell length) sampled monthly over a 17-month period at the Atlantic coast of Portugal. Average radionuclide concentration values in mussels were 759 {+-} 277 Bq kg{sup -1} for {sup 210}Po (range 460-1470 Bq kg{sup -1} dry weight), and 45 {+-} 19 Bq kg{sup -1} for {sup 210}Pb (range 23-96 Bq kg{sup -1} dry weight). Environmental parameters and mussel biometric parameters were monitored during the same period. Although there was no seasonal variation of radionuclide concentrations in sea water during the study period, the concentration of radionuclide activity in mussels varied seasonally displaying peaks of high concentrations in winter and low concentrations in summer. Analysis of radionuclide data in relation to the physiological Condition Index of mussels revealed that {sup 210}Po and {sup 210}Pb activities in the mussel (average activity per individual) remained nearly constant during the investigation period, while mussel body weight fluctuated due to fat storage/expenditure in the soft tissues. Similar variation of radionuclide concentrations was observed in mussels transplanted from the sea coast into the Tejo Estuary. However, under estuarine environmental conditions and with higher food availability throughout the year, transplanted mussel Condition Index was higher than in coastal mussels and average radionuclide concentrations were 210 {+-} 75 Bq kg{sup -1} (dry weight) for {sup 210}Po and 10 {+-} 4 Bq kg{sup -1} (dry weight) for {sup 210}Pb, therefore lower than in coastal mussels with similar shell length. It is concluded that the apparent seasonal fluctuation and inter-site difference of radionuclide concentrations were mostly caused by mussel body weight fluctuation and not by radionuclide body burden fluctuation. This interpretation can be extended to the apparent seasonal fluctuation in concentrations of lipophilic and lipophobic contaminants in

Radionuclide concentrations in raw and purified phosphoric acids from Brazil and their processing wastes: implications for radiation exposures.

Science.gov (United States)

da Conceição, Fabiano Tomazini; Antunes, Maria Lúcia Pereira; Durrant, Steven F

2012-02-01

Radionuclides from the U and Th natural series are present in alkaline rocks, which are used as feedstock in Brazil for the production of raw phosphoric acid, which can be considered as a NORM (naturally occurring radioactive material). As a result of the purification of raw phosphoric acid to food-grade phosphoric acid, two by-products are generated, i.e., solid and liquid wastes. Taking this into account, the main aim of this study was to evaluate the fluxes of natural radionuclide in the production of food-grade phosphoric acids in Brazil, to determine the radiological impact caused by ingestion of food-grade phosphoric acid, and to evaluate the solid waste environmental hazards caused by its application in crop soils. Radiological characterization of raw phosphoric acid, food-grade phosphoric acid, solid waste, and liquid waste was performed by alpha and gamma spectrometry. The (238)U, (234)U, (226)Ra, and (232)Th activity concentrations varied depending on the source of raw phosphoric acid. Decreasing radionuclides activity concentrations in raw phosphoric acids used by the producer of the purified phosphoric acid were observed as follows: Tapira (raw phosphoric acid D) > Catalão (raw phosphoric acids B and C) > Cajati (raw phosphoric acid A). The industrial purification process produces a reduction in radionuclide activity concentrations in food-grade phosphoric acid in relation to raw phosphoric acid produced in plant D and single raw phosphoric acid used in recent years. The most common use of food-grade phosphoric acid is in cola soft drinks, with an average consumption in Brazil of 72 l per person per year. Each liter of cola soft drink contains 0.5 ml of food-grade phosphoric acid, which gives an annual average intake of 36 ml of food-grade phosphoric acid per person. Under these conditions, radionuclide intake through consumption of food-grade phosphoric acid per year per person via cola soft drinks is not hazardous to human health in Brazil

Patterns of radionuclide concentrations in life-cycle of birds

International Nuclear Information System (INIS)

Lebedeva, N.V.; Beloglazov, M.V.

1995-01-01

Breeding populations of Great Tit Parus major and Pied Flycatcher Ficedida hypoleuca was studied to determine radionuclide ( 137 Cs, 90 Sr) concentrations in bodies and foods (contents of gastrointestinal tracts) at different stages of the life-cycle and radiation effects upon the populations. The study was carried out in 1989--1992 near Chernobyl (in two areas with differed contamination levels: 90 Ci/km 2 , 5 Ci/km 2 ) and East-Ural radioactive trace (Russia) (1,500 Ci/km 2 , 2 Ci/km 2 ). Concentrations of 90 Sr in egg shells of Great Tit collected near Chernobyl were 65 times higher in the more radioactive area than in the less contaminated area and varied from 56.6 to 79.7 Bq/g. Concentration of 90 Sr in the contents of gastrointestinal tracts were from 0 to 10.8 Bq/g. Concentrations of radionuclides in the food increased in the sequence ''nestlings 90 Sr content in bodies of nestlings varied from 1 to 5 Bq/g at contaminated site and from 0.2 to 0.5 Bq/g at less polluted area, from 1 to 9 Bq/g and from 0.1 to 0.5 Bq/g in fledglings relatively in two areas. It was assumed that the ration of pairs numbers and breeding success of Pied Flycatcher (East-Ural) on the control site was significantly higher than that on contaminated site. The pathology in development of Pied Flycatcher's nestling was recorded. The radiation influenced on age-structure of bird populations decreasing the ratio of the young

Radionuclide concentrations in underground waters of Mururoa and Fangataufa Atolls.

Science.gov (United States)

Mulsow, S; Coquery, M; Dovlete, C; Gastaud, J; Ikeuchi, Y; Pham, M K; Povinec, P P

1999-09-30

In 1997 an expedition to Mururoa and Fangataufa Atolls was carried out to sample underground waters from cavity-chimneys and carbonate monitoring wells. The aim of this study was to determine the prevailing concentration and distribution status of radionuclides. Elemental analysis of interstitial waters was carried out in the water fraction as well as in particles collected at 11 underground monitoring wells. 238Pu, 239,240Pu, 241Am, 137Cs, 90Sr, 3H, 125Sb, 155Eu and 60Co were analyzed in both fractions by alpha-, beta- and gamma-spectrometry. Measurements showed that at 60% of the sites, pH and Eh seemed to be related to tidal cycles; in contrast HTO was constant during the sampling time. Interstitial waters from carbonates and transition zones shared similar chemical composition that were not different from that of the surrounding seawater. Waters collected from basalt cavities left after nuclear tests, (Aristee and Ceto) have a different chemical signature characterized by a deficiency in Mg, K and SO4 as well as enrichment in Sr, Si, Al and Cl compared to the rest of the stations. Radionuclide concentrations present in both, water and particulate fractions, were significantly higher at Ceto and Aristee than at any other monitoring wells, except for Fuseau and Mitre monitoring wells (Fangataufa) where values similar to Ceto were found (e.g. 239,240Pu: > 20 mBq g-1). Considering that Pu isotopes showed high Kd values compared to non-sorbing radionuclides such as 3H, 90Sr and 137Cs it is very unlikely that migration from cavities to monitoring wells accounts for the concentration of Pu isotopes and Am at Fuseau 30 and Mitre 27. Perhaps the contact of lagoon waters with the well before sealing could be a possible source of the transuranics found at these sites. The 238Pu/239,240Pu ratios measured in the particles were similar to that of the lagoon (0.38), thus supporting this hypothesis. The fact that transuranics were found only in the particle fraction, in the

Radionuclide concentrations in terrestrial vegetation and soil on and around the Hanford Site, 1983 through 1993

International Nuclear Information System (INIS)

Poston, T.M.; Antonio, E.J.; Cooper, A.T.

1995-08-01

This report reviews concentrations of 60 Co, 90 Sr, 137 Cs, U isotopes, 238 Pu, 239,240 Pu, and 241 Am in soil and vegetation samples collected from 1983 through 1993 during routine surveillance of the Hanford Site. Sampling locations were grouped in study areas associated with operational areas on the Site. While radionuclide concentrations were very low and representative of background concentrations from historic fallout, some study areas on the Site contained slightly elevated concentrations compared to other study areas onsite and offsite. The 100 Areas had concentrations of 60 Co comparable to the minimum detectable concentration of 0.02 pCi/g in soil. Concentrations of 90 Sr, 137 Cs, 238 Pu, 239,240 Pu, and 241 Am in 200 Area soils were slightly elevated. The 300 Area had a slight elevation of U in soil. These observations were expected because many of the sampling locations were selected to monitor specific facilities or operations at the operational areas. Generally, concentrations of the radionuclides studied were greater and more readily measured in soil samples compared to vegetation samples. The general pattern of concentrations of radionuclide concentrations in vegetation by area mirrored that observed in soil. Declines in 90 Sr in soil appear to be attributed to radioactive decay and possibly downward migration out of the sampling horizon. The other radionuclides addressed in this report strongly sorb to soil and are readily retained in surface soil. Because of their long half-lives compared to the length of the study period, there was no significant indication that concentrations of U isotopes and Pu isotopes were decreasing over time

Contributions by emissions from nuclear installations to concentrations of radionuclides in milk

CERN Document Server

Green, N

1983-01-01

A year-long study has been carried out to determine whether milk produced near nuclear sites contains concentrations of radionuclides that can be attributed to discharges from the installations, and, as a consequence, whether there is enhanced exposure of those members of the public who consume this milk. Eight creameries were chosen and monthly samples of milk were taken for analysis. The concentrations of caesium-137 and strontium-90 were measured and compared with results from a national survey conducted as part of the Board's environmental radioactivity surveillance programme. No effect attributable to discharges from the nuclear establishments was identified. The activity concentrations ranged between 0.1 and 3 times the national average; the variation relates mainly to rainfall in the area, although other factors may also have an effect. However, milk contributes only a small fraction of the total dietary intake of caesium-137 and strontium-90, and so the exposure of persons consuming the milk varies on...

The administered activity of radionuclides in nuclear medicine

International Nuclear Information System (INIS)

Nakamura, Mototoshi; Koga, Sukehiko; Kondo, Takeshi

1993-01-01

A survey of 104 hospitals was conducted to determine the administered activity of radionuclides. Eighty-five hospitals responded, and reported a total of 119,614 examinations in one year. The examinations included: bone scintigraphy, 26.4%; thallium-201 ( 201 Tl) myocardial scintigraphy, 15.5%; gallium-67 ( 67 Ga) scintigraphy, 13.3%; N-isopropyl-p-[ 123 I] iodoamphetamine (IMP) brain perfusion scintigraphy, 7.0%. The administered activity was corrected by body weight only for children at more than 80% of the responding hospitals. The number of hospitals that reported over-administration of radionuclide varied according to the type of scintigraphy performed: bone, 76%; inflammatory ( 67 Ga), 93%; myocardial ( 201 Tl), 89.2%; brain (IMP), 8.5%. The administered activity of IMP was closer to the upper limits specified in the Recommendations on Standardization of Radionuclide Imaging by the Japan Radioisotope Association (1987), because IMP is very expensive and is supplied as single vials. The highest average effective dose was for myocardial scintigraphy, the second-highest for inflammatory scintigraphy, and the third-highest for bone scintigraphy. In 201 Tl and 67 Ga scintigraphy, the entire contents of the vial may be administered two days before the expiration date, because the ratio of (true patient administered activity) to (declared patient administered activity) is similar to the ratio of (radioactivity on the day of supply) to (radioactivity on the day of expiration). The factors that influence administered activity are through put, price of the radionuclide, and whether the radionuclide is sold as a single vial. In order to decrease the effective dose, it is necessary to establish a close cooperation between medical personnel, the makers of radiopharmaceuticals, and manufactures of gamma cameras. (author)

Method to determine the activity concentration and total activity of radioactive waste

International Nuclear Information System (INIS)

Angeles C, A.

2001-02-01

A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients

Radionuclide concentrations in the northern part of The Netherlands after the Chernobyl reactor accident

International Nuclear Information System (INIS)

de Meijer, R.J.; Aldenkamp, F.J.; Brummelhuis, M.J.; Jansen, J.F.; Put, L.W.

1990-01-01

Concentrations of radionuclides originating from the Chernobyl reactor accident were measured as a function of time in air, rainwater, grass, cow's milk, vegetables and dust by means of high-resolution gamma-ray spectroscopy. Special attention was paid to grass and milk originating from the same meadows. Also, milk of cows temporarily kept inside after the accident was monitored until a few days after their release from the stables. Activity ratios in various types of samples and the implication of the sheltering measures for cows are discussed

Evaluation of concentration limits of radionuclides produced by accelerators

International Nuclear Information System (INIS)

Shibata, Tokushi; Ohkubo, Tohru; Uwamino, Yoshitomo; Iwai, Satoshi; Satoh, Osamu; Rintsu, Yukoh; Fukumoto, Toshiharu.

1992-01-01

This report describes the evaluation of concentration limits of 78 radionuclides typically produced by accelerator facilities and not listed in ICRP Pub. 30. The evaluation method and system have been developed in the present study. The evaluated values were compared with tremendously severe concentration limits given in the Annex Table 2 of the Science and Technology Agency Notification No. 15 which describes the concentration limits of the nuclides of which concentration limits are not given in the Annex Table 1 of the Agency Notification No. 15. The results show that two to nine order larger limits should be used. The new limits rationalize greatly the internal exposure control and the design of accelerator facilities. Simple and convenient techniques are also discussed for finding concentration limits of very-short-lived nuclides without knowing detail information about the nuclides such as decay scheme and metabolic data. (author)

Ground depositions and air concentrations of Chernobyl fallout radionuclides at Munich-Neuherberg

Energy Technology Data Exchange (ETDEWEB)

Hoetzl, H.; Rosner, G.; Winkler, R.

1987-01-01

Southern Bavaria has received a comparatively high deposition of fallout radionuclides from the reactor accident at Chernobyl. As a result, in addition to the measurement of numerous gamma emitting nuclides and of strontium isotopes, the determination of several actinides, including isotopes of uranium, neptunium, plutonium and curium was possible. The observed radionuclide composition of the fallout and the time course of ground deposition and air concentration at the site of the Gesellschaft fuer Strahlen- und Umweltforschung (GSF) at Neuherberg, 10 km north of Munich, are reported and discussed.

Ground depositions and air concentrations of Chernobyl fallout radionuclides at Munich-Neuherberg

International Nuclear Information System (INIS)

Hoetzl, H.; Rosner, G.; Winkler, R.

1987-01-01

Southern Bavaria has received a comparatively high deposition of fallout radionuclides from the reactor accident at Chernobyl. As a result, in addition to the measurement of numerous gamma emitting nuclides and of strontium isotopes, the determination of several actinides, including isotopes of uranium, neptunium, plutonium and curium was possible. The observed radionuclide composition of the fallout and the time course of ground deposition and air concentration at the site of the Gesellschaft fuer Strahlen- und Umweltforschung (GSF) at Neuherberg, 10 km north of Munich, are reported and discussed. (orig.)

An international database of radionuclide concentration ratios for wildlife: development and uses.

Science.gov (United States)

Copplestone, D; Beresford, N A; Brown, J E; Yankovich, T

2013-12-01

A key element of most systems for assessing the impact of radionuclides on the environment is a means to estimate the transfer of radionuclides to organisms. To facilitate this, an international wildlife transfer database has been developed to provide an online, searchable compilation of transfer parameters in the form of equilibrium-based whole-organism to media concentration ratios. This paper describes the derivation of the wildlife transfer database, the key data sources it contains and highlights the applications for the data. Copyright © 2013 Elsevier Ltd. All rights reserved.

Criteria for requesting specific radionuclide analysis through gross α and gross β concentration measurements in environmental samples

International Nuclear Information System (INIS)

Ferreira, E.G.

1988-01-01

This paper suggests some criteria for the decision to proceed with the analysis of specific radionuclides based on results of the determination of gross α and β concentrations in environmental samples of aerosols, water, dairy and agricultural products, soil and sediments. The samples considered are provenient from the environmental surveillance of uranium mining and milling facilities as well as the mining and processing plants of monazite sands. The radionuclides to be analysed are those considered to be the most critical to human health, that is: U-nat; Th-nat; Th-230; Ra-228; Ra-226; Po-210; Pb-210. The measured gross α and β concentrations will be compared with the Maximum Allowable Concentrations for some defined radionuclides. Radiochemical analysis of specific radionuclides may then become necessary, depending upon the results of this comparison. The main goal of the proposed guide is to simplify and to discipline the execution of environmental surveillance programs in a safe and economical way, avoiding unnecessary analysis. (author) [pt

The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants

International Nuclear Information System (INIS)

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-01-01

The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11–12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO 2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides as well as 40 K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in

The activity of selected gamma radionuclides in the Tatra National Park

Directory of Open Access Journals (Sweden)

Kubica Barbara

2017-01-01

Full Text Available Cesium is naturally occurring active metal, represented by one stable isotope 133Cs, and number of artificial, unstable, isotopes. The most common artificial isotope of cesium is 137Cs, present in the environment of the Tatra Mountains due to nuclear weapon testing in late `50, and nuclear reactor accident in Chernobyl in 1986. However in recent years the growth in biofuels use for power generation can be the next source of 137Cs emission. Burning wood cultivated on grounds contaminated by 137Cs can introduce secondary emission of this isotope to the atmosphere.This paper presents the results of determination of gamma emitting radionuclides artificial 137Cs and natural 40K in soil samples from the Tatra Mountains. Results show some differences in the vertical distribution of examined radionuclides. It was found that the change of activity of 137Cs in the soil samples depends mostly on the soil density and on the concentration of organic material. The state of “zero” 137Cs activity was developed in the form of maps.

Nominal Range Sensitivity Analysis of peak radionuclide concentrations in randomly heterogeneous aquifers

International Nuclear Information System (INIS)

Cadini, F.; De Sanctis, J.; Cherubini, A.; Zio, E.; Riva, M.; Guadagnini, A.

2012-01-01

Highlights: ► Uncertainty quantification problem associated with the radionuclide migration. ► Groundwater transport processes simulated within a randomly heterogeneous aquifer. ► Development of an automatic sensitivity analysis for flow and transport parameters. ► Proposal of a Nominal Range Sensitivity Analysis approach. ► Analysis applied to the performance assessment of a nuclear waste repository. - Abstract: We consider the problem of quantification of uncertainty associated with radionuclide transport processes within a randomly heterogeneous aquifer system in the context of performance assessment of a near-surface radioactive waste repository. Radionuclide migration is simulated at the repository scale through a Monte Carlo scheme. The saturated groundwater flow and transport equations are then solved at the aquifer scale for the assessment of the expected radionuclide peak concentration at a location of interest. A procedure is presented to perform the sensitivity analysis of this target environmental variable to key parameters that characterize flow and transport processes in the subsurface. The proposed procedure is exemplified through an application to a realistic case study.

Study of radionuclide and element characterization of Angola marine sediment using low background gamma spectrometry and instrumental neutron activation analysis techniques

International Nuclear Information System (INIS)

Teixeira, M.C.P.; Vuong Huu Tan; Truong Y; Ho Manh Dung; Le Nhu Sieu; Cao Dong Vu; Nguyen Thanh Binh

2007-01-01

The concentrations of radionuclides and chemical elements in Angola marine sediment samples were determined by using low background gamma (LBG) spectrometry and instrumental neutron activation analysis (INAA). The combination of radionuclide and elemental concentration values yielded synergy in the validation of analytical data and identification of sediment sources modeled by multivariate factor analysis. Varimax rotation factor analysis based on the elemental concentrations revealed five sources contributed to the sediment composition, i.e. crustal, sea-salt, industrial, coal-related and Se-related sources. (author)

Evaluation of the anthropogenic radionuclide concentrations in sediments and fauna collected in the Beaufort Sea and northern Alaska

International Nuclear Information System (INIS)

Efurd, D.W.; Miller, G.G.; Rokop, D.J.

1997-07-01

This study was performed to establish a quality controlled data set about the levels of radio nuclide activity in the environment and in selected biota in the U.S. Arctic. Sediment and biota samples were collected by the National Oceanic and Atmospheric Administration (NOAA), the National Biological Service, and the North Slope Borough's Department of Wildlife Management to determine the impact of anthropogenic radionuclides in the Arctic. The results summarized in this report are derived from samples collected in northwest Alaska with emphasis on species harvested for subsistence in Barrow, Alaska. Samples were analyzed for the anthropogenic radionuclides 90 Sr, 137 Cs, 238 Pu, 239 Pu, 240 Pu and 241 Am. The naturally occurring radionuclides 40 K, 212 Pb and 214 Pb were also measured. One goal of this study was to determine the amounts of anthropogenic radionuclides present in the Beaufort Sea. Sediment samples were isotopically fingerprinted to determine the sources of radio nuclide activities. Biota samples of subsistence and ecological value were analyzed to search for evidence of bio-accumulation of radionuclides and to determine the radiation exposures associated with subsistence living in northern Alaska. The anthropogenic radio nuclide content of sediments collected in the Beaufort Sea was predominantly the result of the deposition of global fallout. No other sources of anthropogenic radionuclides could be conclusively identified in the sediments. The anthropogenic radio nuclide concentrations in fish, birds and mammals were very low. Assuming that ingestion of food is an important pathway leading to human contact with radioactive contaminants and given the dietary patterns in coastal Arctic communities, it can be surmised that marine food chains are presently not significantly affected

Cosmogenic radionuclide 7Be in atmospheric fallouts, weather factors and solar activity

International Nuclear Information System (INIS)

Kungurov, F.R.

2011-11-01

Key words: 7 Be activity, atmospheric fallouts, solar activity, gamma spectroscopy. Subjects of research: cosmogenic radionuclide 7 Be in atmospheric fallouts and surrounding objects of environment, its migrational distribution connected to solar activity and weather meteorologic parameters of the region studied. Purpose of work: Defining correlation between atmospheric humidity and solar activity with concentration and distribution of cosmogenic radionuclide 7 Be. Methods of research: gamma-spectrometry method of activity measurements. The results obtained and their novelty: Cycle of research works on definition of concentration and migrational distribution of CRN 7 Be in Samarkand region during 2002-2005 was carried out for the first time. Volumetric activity of 7 Be in squat air layer of Samarkand was determined. Average density of 7 Be fallouts for the four years of studies was determined. Qualitative correlation bet ween 7 Be fallouts density variations and solar activity, expressed through Wolf number has been found. Qualitative correlation between 7 Be fallouts density variations and amount of precipitations has been found. Regularity in 7 Be concentration decrease towards north latitudes has been detected. Practical value: Developed scintillation method of 7 Be activity detection in atmospheric fallouts was used in works performed in the framework of republican grants 2F-No 1.2.3, CNT RUz PFNI 2F-No 2.1.39 and ITD-7-024. Methodology was used for the estimation of the velocity of erosion processes in the soils of different regions of Uzbekistan. Methodology is used in the works on 7 Be radioactivity measurements. Degree of embed and economic effectivity: Gained results replenish database on 7 Be isotope distribution on Earth regions and its role in formation of some processes, connected with meteorology, agronomy and radioecology of Samarkand region. Field of application: meteorology, agronomy and radioecology. (author)

Radionuclide transport along a boreal hill slope - elevated soil water concentrations in riparian forest soils

Energy Technology Data Exchange (ETDEWEB)

Lidman, Fredrik; Boily, Aasa; Laudon, Hjalmar [Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901 83 Umeaa (Sweden); Koehler, Stephan J. [Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, P.O. 7050, 750 07 Uppsala (Sweden)

2014-07-01

The transport of radionuclides from forest ecosystems and out into surface waters is a crucial process for understanding the long-term fate of radionuclides in the boreal landscape. Boreal forests are typically dominated by podzol soils, but the streams draining the forests are often lined by highly organic, often peat-like soils, which the radionuclides must pass through in order to reach the stream. This so-called riparian zone therefore represents a fundamentally different biogeochemical environment than ordinary forest soils, e.g. by exhibiting significantly lower pH and higher concentrations of organic colloids, which significantly can affect the mobility of many radionuclides. Since the riparian zone is the last terrestrial environment that the groundwater is in contact with before it enters the stream, previous research has demonstrated its profound impact on the stream water chemistry. Hence, the riparian soils should also be important for the transport and accumulation of radionuclides. Therefore, soil water was sampled using suction lysimeters installed at different depths along a 22 m long forested hill slope transect in northern Sweden, following the flow pathway of the groundwater from the uphill podzol to the riparian zone near the stream channel. The analyses included a wide range of hydrochemical parameters and many radiologically important elements, e.g. U, Th, Ni, C, Sr, Cs, REEs and Cl. The sampling was repeated ten times throughout a year in order to also capture the temporal variability of the soil water chemistry. The water chemistry of the investigated transect displayed a remarkable change as the groundwater approached the stream channel. Strongly increased concentrations of many elements were observed in the riparian soils. For instance, the concentrations of Th were more than 100 times higher than in the riparian zone than in the uphill forest, suggesting that the riparian zone may be a hotspot for radionuclide accumulation. The reason

Estimating radionuclide air concentrations near buildings: a screening approach

International Nuclear Information System (INIS)

Miller, C.W.; Yildiran, M.

1984-01-01

For some facilities that routinely release small amounts of radionuclides to the atmosphere, such as hospitals, research laboratories, contaminated clothing laundries, and others, it is necessary to estimate the dose to persons very near the buildings from which the releases occur. Such facilities need simple screening procedures which provide reasonable assurance that as long as the calculated dose is less than some fraction of a relevant dose limit no individual will receive a dose in excess of that limit. Screening procedures have been proposed for persons living within hundreds of meters to a few kilometers from a source of radioactive effluent. This paper examines a screening technique for estimating long-term average radionuclide air concentrations within approximately 100 m of a building from which the release occurs. The technique is based on a modified gaussion plume model (HB model) which considers the influence of the tallest building within 100 m and is independant of atmospheric stability and downwind distance. 4 references, 2 tables

Determination of uranium and thorium activity concentrations using activation analysis in beach sands from extreme south Bahia, Brazil

International Nuclear Information System (INIS)

Vasconcelos, Danilo C.; Oliveira, Arno H.; Silva, Mario R.S.; Penna, Rodrigo; Santos, Talita O.; Pereira, Claubia; Rocha, Zildete; Menezes, Maria Angela B.C.

2009-01-01

Levels of natural radioactivity are the major cause of external exposure to gamma radiation. Thus, the determination of activity concentration of primordial radionuclides, such as 238 U and 232 Th, in soils, sand and rock is of basic importance to estimate the radiation levels to which man is directly or indirectly exposed. In order to study the process of specific activity of 238 U and 232 Th, beaches sands samples were collected from eight different locations in extreme south of Bahia state from Brazil. The samples have been analyzed by instrumental neutron activation analyses and for determination of thorium concentrations and delayed neutrons analysis for determination of uranium. The mean specific activity for 238 U and 232 Th was higher in Cumuruxatiba than in others locations studied. Alcobaca and Caraiva also presented high values. The concentrations of these radionuclides were compared with typical world values and Cumuruxatiba have specific activity higher than the others locations, 2,984 Bq/kg maximum value for 238 U and 1,8450 Bq/kg maximum value for 232 Th and activity concentrations in Cumuruxatiba are higher in black sand than in no black sand, suggesting presence of monazite.(author)

Colloid-Associated Radionuclide Concentration Limits: ANL

International Nuclear Information System (INIS)

Mertz, C.

2000-01-01

The purpose and scope of this report is to describe the analysis of available colloidal data from waste form corrosion tests at Argonne National Laboratory (ANL) to extract characteristics of these colloids that can be used in modeling their contribution to the source term for sparingly soluble radioelements (e.g., Pu). Specifically, the focus is on developing a useful description of the following waste form colloid characteristics: (1) composition, (2) size distribution, and (3) quantification of the rate of waste form colloid generation. The composition and size distribution information are intended to support analysis of the potential transport of the sparingly soluble radionuclides associated with the waste form colloids. The rate of colloid generation is intended to support analysis of the waste form colloid-associated radionuclide concentrations. In addressing the above characteristics, available data are interpreted to address mechanisms controlling colloid formation and stability. This report was developed in accordance with the ''Technical Work Plan for Waste Form Degradation Process Model Report for SR'' (CRWMS M and O 2000). Because the end objective is to support the source term modeling we have organized the conclusions into two categories: (1) data analysis conclusions and (2) recommendations for colloid source term modeling. The second category is included to facilitate use of the conclusions from the data analysis in the abstraction of a colloid source term model. The data analyses and conclusions that are presented in this report are based on small-scale laboratory tests conducted on a limited number of waste glass compositions and spent fuel types

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1983-01-01

Radionuclide migration have been studied in natural fissures orieted parallel to the axis of granite drill cores. A short pulse of the radionuclides solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. After several hundred fissure volumes water had been pumped through the fissure following the radionuclide pulse the activity distribution on the fissure surfaces was measured. From the retardation of 152 Eu, 235 Np and 237 Pu it is concluded that these radionuclides are transported in the oxidation states Eu(III), Pu(IV) and Np(V). The distribution coefficients K sub (d) calculated from flow and activity distribution data on the basis of geometric surface area/volume ratios are of the same order as published K sub (d) values obtained from batch equilibrium experiments. (Author)

Natural radionuclides in Italian diet and their annual intake

International Nuclear Information System (INIS)

Donatella Desideri; Maria Assunta Meli; Carla Roselli; Laura Feduzi; Nevio Forini; Alba Rongoni

2014-01-01

This study was dedicated to the evaluation of the background activity concentration of natural radionuclides as 228 Ra and 228 Th of 232 Th family, 226 Ra of 238 U family and 40 K in the Italian daily diet. These radionuclides were determined by gamma spectrometry. 40 K activity concentration, in the samples taken into account in the present paper, ranged between 70.5 (milk) and 181.1 Bq kg ww -1 (pasta), 226 Ra activity concentration ranged between 1.1 (milk) and 5.7 Bq kg ww -1 (pasta), 228 Ra and 228 Th activity concentration, in the same samples, ranged between 0.7 (milk) and 3.7 Bq kg ww -1 (pasta) and between 1.4 (milk) and 6.1 Bq kg ww -1 (flours) respectively. The annual intake of every radionuclide from foodstuffs ingestion was also calculated. The 94-95 % of the total intake comes from 40 K. For adults and children, the highest activity intake of all radioisotopes was from grain products, for infants it was from milk products. (author)

Long-term variations of man-made radionuclide concentrations in a bio-indicator Mytilus galloprovincialis from the French Mediterranean coast

International Nuclear Information System (INIS)

Charmasson, S.; Barker, E.; Calmet, D.; Pruchon, A.S.; Thebault, H.

1999-01-01

Results from a 14-year monitoring (1984-1997) of man-made radionuclide (137Cs and 106Ru) levels in Mytilus galloprovincialis collected monthly on the French Mediterranean coast are presented. In this area sources of man-made radionuclides are on the one hand atmospheric fallout from both the past nuclear testings and the Chernobyl accident and on the other hand discharges from nuclear installations located on the Rhone River banks, especially those from the spent nuclear fuel reprocessing plant in Marcoule. Long-term variations of radionuclide concentrations in Mytilus demonstrated seasonal variations which are linked to the reproductive cycle of these organisms as well as to variations in land-based inputs of man-made radionuclides. A comparative study of these seasonal variations has been carried out with the aid of spectral analysis. Due to differences in released activities and discharge patterns, flow rates appear to govern mainly the 137Cs variations in the Rhone waters, whereas 106Ru variations are driven by the discharges. In the area under the influence of the Rhone outflow, 137Cs variations in mussels are characterized by seasonal variations which are themselves inversely correlated with variations of 137Cs concentrations in Rhone waters. This cyclic component seems to be closely linked to the mussel reproductive cycle. The possible influence of other parameters is discussed

Metabolic transformation of radionuclides in marine organisms

International Nuclear Information System (INIS)

Koyanagi, Taku

1987-01-01

Physico-chemical form of radionuclides is one of the important factors governing the concentration by marine organisms, whereas biological activities affect the existing states of radionuclides especially in coastal waters. Radioiodine in the form of iodate which is predominant species in seawater is reduced to iodide ion by biological activities and concentration factor of iodide is an order of magnitude higher than those of iodate. Extremely high accumulation of transition elements, actinides, or natural radionuclides in branchial heart of octopus is explained by the fuction of adenochrome, a glandular pigment in the organ as a natural complexing agent, and similar metal-binding proteins with relatively low molecular weight have been found in various marine invertebrates. High accumulation of some elements also found in mollusk kidney is considered to be caused by the intracellular concretions composed of calcium phosphate. All these biological processes suggest the significance of further investigations on metabolic transformation of radionuclides in marine organisms. (author)

Radionuclides in sporocarps of medicinaly important fungi of Fruska Gora hill

International Nuclear Information System (INIS)

Karaman, M.; Matavulj, M.; Čonkić, L.

2002-01-01

The content of radionuclides in six lignicolous saprophytic and parasitic fungal species was analyzed. Samples were collected in 1999 autumn at two sites of the Fruska Gora Hill. Since fungi absorb radionuclides mostly from the substrate, soil and tree samples were also collected and analyzed. Certain characteristics of fungal species play an important role in the process of radionuclide absorption. On the other hand, the degree of radionuclide accumulation is very important for the fungi of potential pharmaceutical significance. The results on the radioactivity concentration in the analyzed fungi could be used both for the bioindication investigations, soil and substrate contamination in particular, and for estimation of the forest ecological status. The activity concentration level of most critical radionuclide 137Cs was about ten times lower in these species then in Pholiota squarrosa, characterized by the highest activity concentration level of 55(4) Bq/kg (d.m.) [sr

A qualitative evaluation of radionuclide concentrations in Hanford Site Wildlife, 1983 through 1992

International Nuclear Information System (INIS)

Poston, T.M.; Cooper, A.T.

1994-10-01

Environmental monitoring has been conducted at the U.S. Department of Energy's (DOE's) Hanford Site in southeastern Washington State since 1945. Fish and wildlife have been monitored since 1945, however, a major emphasis on mammals did not occur until the 1970s. This report focuses on the 10-year period from 1983 through 1992. The objectives of this report are to evaluate 90 Sr and 137 Cs concentrations in Site wildlife populations and, when possible, evaluate trends in concentrations over this period of time. No distinct trends in radionuclide concentrations were apparent in most species sampled. Many measurements were at or below the analytical limit of detection. This evaluation found that concentrations of 90 Sr in rabbit and deer bone were elevated in animals collected from areas adjacent to industrialized areas. Similarly, radionuclide concentrations in duck muscle from waterfowl collected at B Pond were elevated with 137 Cs when compared to background concentrations. None of the measured concentrations were high enough to pose any risk to theoretical human consumers of game animals inhabiting the Hanford Site. Estimates of the annual dose from the consumption of 40 kg (88 lb) of Hanford Site wildlife were less than 0.001 times the National Council on Radiation Protection and Measurements and the DOE guideline of 100 mrem/yr

Twenty-five years of environmental radionuclide concentrations near a nuclear power plant.

Science.gov (United States)

Harris, Charles; Kreeger, Danielle; Patrick, Ruth; Palms, John

2015-05-01

The areas in and along a 262-km length of the Susquehanna River in Pennsylvania were monitored for the presence of radioactive materials. This study began two months after the 1979 Three Mile Island (TMI) partial reactor meltdown; it spanned the next 25 y. Monitoring points included stations at the PPL Susquehanna and TMI nuclear power plants. Monthly gamma measurements document concentrations of radionuclides from natural and anthropogenic sources. During this study, various series of gamma-emitting radionuclide concentration measurements were made in many general categories of animals, plants, and other inorganic matter. Sampling began in 1979 before the first start-up of the PPL Susquehanna power plant. Although all species were not continuously monitored for the entire period, an extensive database was compiled. In 1986, the ongoing measurements detected fallout from the Chernobyl nuclear accident. These data may be used in support of dose or environmental transport calculations.

Radionuclide concentrations in ground-level air from 1984 to mid 1986 in North Germany and North Norway; influence of the Chernobyl accident

International Nuclear Information System (INIS)

Kolb, W.

1986-09-01

The activity concentration of various fission products and some other radionuclides (e.g. Be-7, Na-22, K-40 and Pb-210) contained in surface air were determined by gamma-ray spectroscopy. The mean monthly activity concentrations of up to 30 radionuclides measured from 1984 to mid 1986 in Brunswick, Berlin and Skibotn (North Norway) are tabulated. Early in 1984 the ground level air at all three stations still contained some fission and activation products resulting from the latest nuclear test carried out at a high altitude by the People's Republic of China. By the end of 1984 only Cs-137 was still detectable with activity concentrations of less than 1 μBq/m 3 . The occasional appearance of some activation products in 1984 and 1985 is commented on and compared with similar findings of several Scandinavian institutes. Fresh fission products from the Chernobyl accident arrived in late April 1986 in Brunswick, Berlin and Skibotn. The mean Cs-137 concentration in May estimated for Brunswick was 28 mBq/m 3 (i.e. 15 times higher than the hitherto recorded maximum in June 1964). It had decreased by July 1986 down to 0.13 mBq/m 3 . The effective dose equivalent due to inhalation of fission products is estimated for all three sites and compared with the Pb-210 inhalation dose. (orig.) [de

Prominent artificial radionuclide activity in the environment of coastal Karnataka on the southwest coast of India

Energy Technology Data Exchange (ETDEWEB)

Narayana, Y. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)]. E-mail: narayanay@yahoo.com; Somashekarappa, H.M.; Karunakara, N.; Avadhani, D.N.; Mahesh, H.M.; Siddappa, K. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)

2000-09-01

Studies on radiation level and radionuclide distribution in the environment of coastal Karnataka were undertaken to provide baseline data for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region and to understand the behaviour of radionuclides in the environment. As part of the programme the concentrations of two important artificial radionuclides, namely {sup 90}Sr and {sup 137}Cs, have been measured in a number of environmental samples. The concentration of {sup 90}Sr is very low in most of the samples. Among the samples analysed for the concentration of {sup 137}Cs, soil samples showed elevated levels of activity in some sampling stations. Among the vegetables, brinjal (Solanum melongena. L) showed considerable activity. The internal dose due to intake of {sup 90}Sr through diet was 0.42 {mu}Sv year{sup -1} for the vegetarian population and 0.32 {mu}Sv year{sup -1} for the non-vegetarian population. The internal dose due to dietary intake of {sup 137}Cs was found to be 0.34 {mu}Sv year{sup -1} and 0.26 {mu}Sv year{sup -1} respectively for the vegetarian and non-vegetarian population. The results are discussed in the light of the literature values reported for other environs of India and abroad and appropriate inferences are drawn. (author)

Modelling the dispersion of radionuclides following short duration releases to rivers

International Nuclear Information System (INIS)

Smith, J.T.; Bowes, M.; Denison, F.H.

2003-01-01

This project develops a model for assessing short duration liquid discharges of radionuclides to rivers. The assessment of doses arising from discharges to rivers is normally carried out by considering annual average discharge rates. Actual authorised discharges, however, may occur unevenly during the year or relatively high short-term discharges could occur in the unlikely event of an incident. Short term radionuclide releases could potentially result in temporary increases in radionuclide activity concentrations in water and fish which are greater than those resulting from a continuous discharge. The purpose of this project is to develop a model to assess short term releases from these sites, and where possible develop generic methods of assessing short term releases. An advection-dispersion model was developed to predict the concentrations of radionuclides in the river environment, ie in river water, river bed sediment and in predatory fish. Uptake of radionuclides to fish was modelled by estimating rates of uptake of radionuclides via the aquatic food chain or across the gill, as appropriate. The model was used to predict the concentrations of the radionuclides in the river Thames and its tributaries as a result of short duration discharges into stretches of the Thames and River Colne. Model output is given as a series of graphs of activity concentration and time integrated activity concentration resulting from a 1 MBq discharge for the following release durations: 5 minutes, 1 h, 3 h, 12 h and 24 h. The five locations for which predictions are given were 100m, 300m, 1000m, 3000m and 10000m downstream. The river volumetric flow rate was shown to be the most important environmental variable determining activity concentrations in water, fish and sediments following a release. In general, the maximum and integrated activity concentrations in water and fish will be in inverse proportion to the river volumetric flow rate, for a given amount and duration of release

Radionuclides in Bayer process residues: previous analysis for radiological protection

International Nuclear Information System (INIS)

Cuccia, Valeria; Rocha, Zildete; Oliveira, Arno H. de

2011-01-01

Natural occurring radionuclides are present in many natural resources. Human activities may enhance concentrations of radionuclides and/or enhance potential of exposure to naturally occurring radioactive material (NORM). The industrial residues containing radionuclides have been receiving a considerable global attention, because of the large amounts of NORM containing wastes and the potential long term risks of long-lived radionuclides. Included in this global concern, this work focuses on the characterization of radioactivity in the main residues of Bayer process for alumina production: red mud and sand samples. Usually, the residues of Bayer process are named red mud, in their totality. However, in the industry where the samples were collected, there is an additional residues separation: sand and red mud. The analytical techniques used were gamma spectrometry (HPGe detector) and neutron activation analysis. The concentrations of radionuclides are higher in the red mud than in the sand. These solid residues present activities concentrations enhanced, when compared to bauxite. Further uses for the residues as building material must be more evaluated from the radiological point of view, due to its potential of radiological exposure enhancement, specially caused by radon emission. (author)

Activity concentrations of 226Ra, 232Th and 40K in brands of fertilisers used in Nigeria

International Nuclear Information System (INIS)

Jibiri, N. N.; Fasae, K. P.

2012-01-01

The activity concentration of naturally occurring radionuclides 40 K, 226 Ra and 232 Th have been measured in different brands of fertiliser samples sold to farmers in retail markets in six commercial cities in southwestern Nigeria. Gamma ray spectroscopy was employed in the measurements of these radionuclides. The results of measurements showed that the average activity concentration of 40 K in the nitrogen, phosphorus and potassium fertilisers across the cities varied from 3972.0 ±416.9 to 5089.3 ±111.3 Bq kg -1 , 9.9 ±7.3 to 450.6 ±14.3 Bq kg -1 for 226 Ra, while for 232 Th it varied from less than lower limit of detection to 15.1 ±2.8 Bq kg -1 . The activity concentrations of 40 K, 226 Ra and 232 Th in single super phosphate (SSP) fertilisers and phosphate rocks were also determined. However, high activity concentrations of 226 Ra were obtained in the SSP fertiliser and phosphate rocks and in particular, two brands of fertilisers from ITL/TAK and F and C companies. The values of the activity concentration of the radionuclides in the brands of fertilisers used in Nigeria are within the range of values reported in several other countries except 40 K. (authors)

Analysis of 137Cs radionuclides activities in Cs-zeolite using gamma spectrometry

International Nuclear Information System (INIS)

Noviarty; Ginting, Aslina Br; Anggraini, Dian; Rosika K

2013-01-01

137 Cs Radionuclide activity analysis has been carried out. The objective is to determine the activity of the 137 Cs radionuclide in Cs-zeolite are packaged in the form of point source. Analysis of 137 Cs Radionuclide activities in Cs zeolite samples was determined by measuring intensity of the isotope 137 Cs gamma energy at 661.7 keV use-y spectrometer. Before measurement the sample, was first carried out measurements of 137 Cs radionuclide in certified point standards from Amersham, to determine the efficiency value. Result the standard sample measurement obtained the efficiency value of 43.98%. Efficiency values obtained are used in the calculation of sample activity. On the measurement of the intensity of the sample obtained results dose rate 196.4537 cps with a standard deviation of 0.5274. By using standard measurement efficiency values obtained by the calculation of the average activity of the radionuclide 137 Cs in Cs-zeolite 524.9082 Bq. Deviation measurements were below 5% (0.27% ) so that the analysis of the activity of radionuclide 137 Cs in Cs-zeolite samples using gamma spectrometer can be accepted with a 95% confidence level. (author)

Distribution of radionuclides in leaf-stem biomass of lupine and clover under production of protein concentrates

International Nuclear Information System (INIS)

Novikov, Yu.F.; Lobach, G.A.; Buzenko, T.A.; Zaretskaya, T.P.

1993-01-01

The basic regularities of radionuclide distribution between the obtained products have been studied using the fractionation of lupine and clover phytomass as an example. The content of radionuclides in protein concentrates has been shown to be strongly related to the crop species. A scheme and a regime of the fractionation of leaf-stem lupine biomass contaminated with cesium radioisotopes and strontium-90 which ensured the minimizing of their residual content in protein-vitaminic and protein concentrates have been selected with due accout of experimental data

Assessment of the concentration limits for radionuclides for Posiva

Energy Technology Data Exchange (ETDEWEB)

Grive, M.; Montoya, V.; Duro, L. (Enviros Spain S.L. (Spain))

2007-01-15

The present document assesses the near-field concentration limits of the radionuclides of interest for Posiva (C, Ni, Se, Sr, Mo, Zr, Nb, Tc, Pd, Sn, Cs, Sm, Ra, Th, Pa, U, Pu, Np, Am and Cm) under the geochemical composition of the Olkiluoto groundwaters. The limits provided here are intended to be used only in the area close to the fuel given that no major solid phases other than the ones produced by the anoxic corrosion of the canister and the fuel itself are considered. Calculations have been performed by using the PHREEQC code. Three different general cases have been considered when assessing the composition of the groundwater contacting the fuel: a) Groundwater contacts the fuel without any prior interaction with the buffer b) Groundwater is modified by interaction with Bentonite, and c) Glacial meltwater reaches the fuel. The redox state of the system has been considered to cover different evolution of the repository for the different groundwaters. Besides of the given redox potential of the groundwaters, two variations of the redox state have been accounted for in this analysis to consider the evolution of H{sub 2} due to the anoxic corrosion of the cast iron insert: (a) The maximum pH{sub 2} overpressure is limited by the hydrostatic and swelling pressure of bentonite at repository depth, and (b) The pH{sub 2} overpressure is limited by the hematite/magnetite stability boundary. This exemplifies the corrosion of iron to magnetite in a first step, and its further evolution to hematite in a second step. Tables summarizing the solubility and aqueous speciation of the different waters as well as the main uncertainty parameters affecting the results are provided. The concentration limits recommended in this report are based on the following assumptions: (i) radionuclides will form individual solid phases, and (ii) the rate of dissolution of radionuclides from spent fuel is fast enough as to ensure that equilibrium with individual solid phases is achieved for

Assessment of the concentration limits for radionuclides for Posiva

International Nuclear Information System (INIS)

Grive, M.; Montoya, V.; Duro, L.

2008-01-01

The present document assesses the near-field concentration limits of the radionuclides of interest for Posiva (C, Ni, Se, Sr, Mo, Zr, Nb, Tc, Pd, Sn, Cs, Sm, Ra, Th, Pa, U, Pu, Np, Am and Cm) under the geochemical composition of the Olkiluoto groundwaters. The limits provided here are intended to be used only in the area close to the fuel given that no major solid phases other than the ones produced by the anoxic corrosion of the canister and the fuel itself are considered. Calculations have been performed by using the PHREEQC code. Three different general cases have been considered when assessing the composition of the groundwater contacting the fuel: a) Groundwater contacts the fuel without any prior interaction with the buffer b) Groundwater is modified by interaction with Bentonite, and c) Glacial meltwater reaches the fuel. The redox state of the system has been considered to cover different evolution of the repository for the different groundwaters. Besides of the given redox potential of the groundwaters, two variations of the redox state have been accounted for in this analysis to consider the evolution of H 2 due to the anoxic corrosion of the cast iron insert: (a) The maximum pH 2 overpressure is limited by the hydrostatic and swelling pressure of bentonite at repository depth, and (b) The pH 2 overpressure is limited by the hematite/magnetite stability boundary. This exemplifies the corrosion of iron to magnetite in a first step, and its further evolution to hematite in a second step. Tables summarizing the solubility and aqueous speciation of the different waters as well as the main uncertainty parameters affecting the results are provided. The concentration limits recommended in this report are based on the following assumptions: (i) radionuclides will form individual solid phases, and (ii) the rate of dissolution of radionuclides from spent fuel is fast enough as to ensure that equilibrium with individual solid phases is achieved for times shorter

Tumour control probability (TCP) for non-uniform activity distribution in radionuclide therapy

International Nuclear Information System (INIS)

Uusijaervi, Helena; Bernhardt, Peter; Forssell-Aronsson, Eva

2008-01-01

Non-uniform radionuclide distribution in tumours will lead to a non-uniform absorbed dose. The aim of this study was to investigate how tumour control probability (TCP) depends on the radionuclide distribution in the tumour, both macroscopically and at the subcellular level. The absorbed dose in the cell nuclei of tumours was calculated for 90 Y, 177 Lu, 103m Rh and 211 At. The radionuclides were uniformly distributed within the subcellular compartment and they were uniformly, normally or log-normally distributed among the cells in the tumour. When all cells contain the same amount of activity, the cumulated activities required for TCP = 0.99 (A-tilde TCP=0.99 ) were 1.5-2 and 2-3 times higher when the activity was distributed on the cell membrane compared to in the cell nucleus for 103m Rh and 211 At, respectively. TCP for 90 Y was not affected by different radionuclide distributions, whereas for 177 Lu, it was slightly affected when the radionuclide was in the nucleus. TCP for 103m Rh and 211 At were affected by different radionuclide distributions to a great extent when the radionuclides were in the cell nucleus and to lesser extents when the radionuclides were distributed on the cell membrane or in the cytoplasm. When the activity was distributed in the nucleus, A-tilde TCP=0.99 increased when the activity distribution became more heterogeneous for 103m Rh and 211 At, and the increase was large when the activity was normally distributed compared to log-normally distributed. When the activity was distributed on the cell membrane, A-tilde TCP=0.99 was not affected for 103m Rh and 211 At when the activity distribution became more heterogeneous. A-tilde TCP=0.99 for 90 Y and 177 Lu were not affected by different activity distributions, neither macroscopic nor subcellular

Seasonal variation of radionuclides in Fucus vesiculosus L. from the Oresund, Southern Sweden

International Nuclear Information System (INIS)

Carlson, L.; Erlandsson, B.

1991-01-01

The activity concentrations of radionuclides ( 60 Co, 54 Mn, 137 Cs, 40 K) in whole plants of Fucus vesiculosus of different ages, and also in tissues of different ages from the same plant were investigated in the vicinity of the Barseback nuclear power plant in southern Sweden. Activity concentration differed between the tissues of different age of the plants, depending on the radionuclide as well as the time of year. The highest concentrations of 60 Co and 54 Mn were measured in the older parts of the plants in spring and summer, while the activity concentrations of 137 Cs and 40 K were highest in receptacles and new vegetative fronds. The discharge of radionuclides from the nuclear power plants was reflected in the measured activity concentration in the algae. For 60 Co, the response seemed to be smoothed out when considering the whole plant, while the new vegetative tissue better reflected the discharge during the autumn. Thus it is important to have knowledge about the autecology of the organism when it is used as an indicator for radionuclides. (author)

Seasonal variation of radionuclides in Fucus vesiculosus L. from the Oeresund, southern Sweden

International Nuclear Information System (INIS)

Carlson, Lena; Erlandsson, Bengt

1990-01-01

The activity concentrations of radionuclides ( 60 Co, 54 Mn, 137 Cs, 40 K) in whole plants of Fucus vesiculosus of different ages and also in tissues of different ages from the same plants were investigated in the vicinity of the Barsebaeck nuclear power plant in southern Sweden. Activity concentration differed between the tissues of different age of the plants, depending on the radionuclide as well as the time of year. The highest concentration of 60 Co and 54 Mn was measured in the older parts of the plants in spring and summer, while the activity concentration of 137 Cs and 40 K was highest in receptacles and new vegetative fronds. The discharge of radionuclides from the nuclear power plant was reflected in the measured activity concentration in the algae. For 60 Co the response seemed to be smoothed out when considering the whole plant, while the new vegetative tissue better reflected the discharge during the autumn. Thus, it is important to have knowledge about the autecology of the organism when it is used as an indicator for radionuclides. (authors)

Vegetation concentration and inventory of metals and radionuclides in the old F-area seepage basin, 904-49G

International Nuclear Information System (INIS)

Murphy, C.E. Jr.

1994-01-01

Measured concentrations of radionuclides and toxic metals are used to calculate the total inventory of in the vegetation growing on the Old F-Area Seepage Basin. Air concentrations and inhalation doses from exposure to smoke from burning the vegetation are calculated to evaluate the effect of open air burning. Radionuclide inventory is one order of magnitude (10 x) less than those necessary to produce a 1 mrem dose. Air concentrations of toxic metals are less than one third the permissible occupational dose

Radionuclide concentrations in oil extraction and production processes in Northeast Brazil; Teores de radionuclideos em processos de extracao e de producao de petroleo no nordeste do Brasil

Energy Technology Data Exchange (ETDEWEB)

Gazineu, Maria Helena Paranhos

2005-06-15

Since the beginning of the twentieth century the presence of naturally occurring radioactive material (NORM) was detected in the water and oil extracted from wells both onshore and offshore. The oil is extracted together with water and sediments which contain radionuclides of the uranium and thorium series. Among the radionuclides present, especial attention should be given to {sup 226}Ra and {sup 228}Ra, due to its long half-life and importance, from the radiological point of view. The objective of this work was to identify the natural radionuclides in the oil industry, to determine their activity concentration, and from these results, to evaluate the risks the employees of the oil industry are exposed to. Samples of sludge, scale and produced water extracted with the oil were collected from three oil processing stations in the state of Sergipe, Brazil. The activity concentrations of the radionuclides were determined in the solid samples before and after the extraction of the oil. The chemical and mineralogical composition of the samples without oil was evaluated. Water samples, on the other hand, were analyzed for their contents of radionuclides and barium concentration. It was observed that the activity concentrations of the analyzed radionuclides ({sup 226}Ra, {sup 228}Ra, {sup 228}Th and {sup 210}Pb) in sludge and scales were very high when compared with the literature, particularly much higher than the values for {sup 226}Ra and {sup 228}Ra obtained for sludge and scales from the oil platforms near the city of Campos, state of Rio de Janeiro. The maximum concentration values for {sup 226}Ra, {sup 228}Ra, {sup 228}Th and {sup 210}Pb (3,500, 2,195, 2,248.6 and 201 kBq kg{sup -1}, respectively) were obtained for the scales after the extraction of the oil. The analysis of the samples showed that barium sulphate (barite) and strontium sulphate (celestite) are the main constituents of the scales, while carbonates and silicates, together with other compounds are the

Primordial Radionuclides Distribution and dose Evaluation in Udagamandalam Region of Nilgiris in India

International Nuclear Information System (INIS)

Manikandan, N. Muguntha; Selvasekarapandian, S.; Sivakumar, R.; Meenakshisundaram, V.; Raghunath, V. M.

2001-01-01

The activity concentration of primordial radionuclides i.e., 238 U series, 232 Th series and 40 K, in soil samples collected from Udagamandalam environment, have been measured by employing NaI (TI) Gamma ray Spectrometer. The absorbed gamma dose rate has also been simultaneously measured by using both environmental radiation dosimeter at each soil sampling location (ambient gamma dose) as well as from the gamma dose derived from the activity concentration of the primordial radionuclides. The results of activity concentration of each radionuclides in soil, absorbed dose rate in air due to soil activity and possible cosmic radiation at each location along with human effective dose equivalent for Udagamandalam environment are presented and discussed

Primordial Radionuclides Distribution and dose Evaluation in Udagamandalam Region of Nilgiris in India

Energy Technology Data Exchange (ETDEWEB)

Manikandan, N. Muguntha; Selvasekarapandian, S.; Sivakumar, R.; Meenakshisundaram, V. [Bharathiar Univ., Coimbatore (India); Raghunath, V. M. [Indira Gandhi Center for Atomic Research, Kalpakkam (India)

2001-09-15

The activity concentration of primordial radionuclides i.e., {sup 238}U series, {sup 232}Th series and {sup 40}K, in soil samples collected from Udagamandalam environment, have been measured by employing NaI (TI) Gamma ray Spectrometer. The absorbed gamma dose rate has also been simultaneously measured by using both environmental radiation dosimeter at each soil sampling location (ambient gamma dose) as well as from the gamma dose derived from the activity concentration of the primordial radionuclides. The results of activity concentration of each radionuclides in soil, absorbed dose rate in air due to soil activity and possible cosmic radiation at each location along with human effective dose equivalent for Udagamandalam environment are presented and discussed.

A qualitative evaluation of radionuclide concentrations in Hanford Site Wildlife, 1983 through 1992

Energy Technology Data Exchange (ETDEWEB)

Poston, T.M.; Cooper, A.T.

1994-10-01

Environmental monitoring has been conducted at the U.S. Department of Energy`s (DOE`s) Hanford Site in southeastern Washington State since 1945. Fish and wildlife have been monitored since 1945, however, a major emphasis on mammals did not occur until the 1970s. This report focuses on the 10-year period from 1983 through 1992. The objectives of this report are to evaluate {sup 90}Sr and {sup 137}Cs concentrations in Site wildlife populations and, when possible, evaluate trends in concentrations over this period of time. No distinct trends in radionuclide concentrations were apparent in most species sampled. Many measurements were at or below the analytical limit of detection. This evaluation found that concentrations of {sup 90}Sr in rabbit and deer bone were elevated in animals collected from areas adjacent to industrialized areas. Similarly, radionuclide concentrations in duck muscle from waterfowl collected at B Pond were elevated with {sup 137}Cs when compared to background concentrations. None of the measured concentrations were high enough to pose any risk to theoretical human consumers of game animals inhabiting the Hanford Site. Estimates of the annual dose from the consumption of 40 kg (88 lb) of Hanford Site wildlife were less than 0.001 times the National Council on Radiation Protection and Measurements and the DOE guideline of 100 mrem/yr.

Distribution of natural radionuclides and uranium activity ratio in Gulf of Thailand sediments as base line data

Energy Technology Data Exchange (ETDEWEB)

Sahoo, S.K.; Hideki, A. [National Institute of Radiological Sciences (Japan); Kritsananuwat, R.; Fukushi, M. [Tokyo Metropolitan University (Japan); Chanyotha, S.; Pangza, K. [Chulalongkorn University (Thailand)

2014-07-01

This paper reports distribution of naturally occurring radionuclides and uranium activity ratio in marine sediments from selected coast, along the Gulf of Thailand to establish baseline data. Thailand has a plan to construct nuclear power plants (NPPs) as well as coal-fired thermal power plants to generate adequate and reliable electricity supply for rapid growth of industrialization. Therefore, it is important to focus not only on security and adequacy of power system but also on environmental protection and monitoring and risk assessment. To carry out environmental monitoring, baseline data plays a significant role. These data should be established and available before set up of mega projects that could impact the environment and health. Therefore, we have collected samples from five areas in the Gulf of Thailand, which are proposed as potential sites, to set up power plants by Thailand government. A total number of fifty-four marine sediment samples were collected. Gamma spectroscopy was used to determine the concentration of natural radionuclides e.g. {sup 226}Ra, {sup 228}Ac and {sup 40}K. Activity concentrations of {sup 226}Ra, {sup 228}Ac and {sup 40}K vary from 2.91-67.17 Bq/kg with an average of 26.64±14.57 Bq/kg, 4.42-109.17 Bq/kg with an average of 43.79±23.92 Bq/kg and 3.36-1004.56 Bq/kg with an average of 393.56±208.04 Bq/kg, respectively. The radiation hazard parameters including absorbed dose rate (D), annual effective dose equivalent (AEDE), radium equivalent activity (AGDE) and external hazard index (Hex) were calculated and compared with the international recommended values. We have noticed that sediments from two sites characterized by similar geological nature of landforms with a rocky coast have higher concentration of natural radionuclides. Concentration of uranium was determined using the inductively coupled plasma mass spectrometry (ICP-MS) and isotopic composition of {sup 234}U/{sup 238}U and {sup 235}U/{sup 238}U were determined using

Radionuclides and particles in seawater with the large volume in situ filtration and concentration system in the coastal waters off Japan

International Nuclear Information System (INIS)

Aono, Tatsuo; Nakanishi, Takahiro; Okubo, Ayako; Zheng, Jian; Yamada, Masatoshi; Kusakabe, Masashi

2008-01-01

It is necessary to determine the radionuclides in dissolved and particulate state in order to clarify the distributions and behavior of these in seawater. Because the concentrations of radionuclides and particles are very low in the ocean, it is difficult to concentrate and fractionate the particulate matters with the filtration systems in seawater. The large volume in situ filtration and concentration system (LV-FiCS) was developed to collect various forms of trace radionuclides and particles in seawater. The LV-FiCS has been operated during several cruises in the coastal waters off Japan, and several m 3 of seawaters were filtered through different kinds of filters and then pass through the adsorbents to concentrate radionuclides simultaneously. This system could be shown the vertical profiles of thorium with the size-fractionated method and the behavior of these nuclides in the ocean. (author)

Selected natural and fallout radionuclides in plant foods around the Kudankulam Nuclear Power Project, India

International Nuclear Information System (INIS)

Ross, E. Mahiban; Raj, Y. Lenin; Wesley, S. Godwin; Rajan, M.P.

2013-01-01

The activity concentrations of certain radionuclides were quantified in some plant foods cultivated around Kudankulam, where a mega-nuclear power plant is being established. The activity concentrations were found more in the ‘pulses’ group and were the lowest in ‘other vegetable’ category. The annual effective dose was computed based on the activity concentration of radionuclides and it was found to be higher due to the consumption of cereals and pulses. Other vegetables, cereals, pulses and nuts recorded high transfer factors for the radionuclide 228 Ra. Fruits, leafy vegetables, tubers and roots, and palm embryo registered high transfer factors for 226 Ra. Group-wise activity concentration, radiation dose to the public and soil-plant-to-transfer factor are discussed in detail. Highlights: ► Fallout radionuclides ( 90 Sr and 137 Cs) were below the limit of detection. ► 228 Ra activities were higher than 226 Ra activity concentrations. ► ‘Pulses’ group (leguminous grains) was the highest accumulator of radium nuclides. ► 228 Ra transfer factor was higher in few groups while 226 Ra was higher in others.

Natural radionuclides in an eucalyptus forest located in the south of Spain

International Nuclear Information System (INIS)

Vaca, F.; Manjon, G.; Garcia-Leon, M.

2001-01-01

Eucalyptus forests can be considered as the main source of raw material for the pulp industry of Spain. This environment was selected for a radioactivity study because natural and artificial radionuclides can be transferred into the pulp mills, associated with raw material, wood and barks, where they are concentrated by industrial processes, becoming a cause of doses. Radionuclide concentration of natural radionuclides ( 238 U, 234 U, 228 Th, 230 Th, 232 Th) were determined by alpha- and gamma-spectrometry. Well-established radiochemical procedures were applied to environmental samples in order to isolate these radionuclides. A comparison between 228 Th activity, determined by gamma-spectrometry, and 232 Th activity, determined by alpha-spectrometry, was used as quality control parameter for analyses. The concentration factors were finally evaluated from experimental data.

Natural gamma-emitting radionuclides in egyptian cement

International Nuclear Information System (INIS)

El Arabi, A.M.; Abbady, A.; El Kamel, A.H.; Nosier, A.; Moustafa, A.

2005-01-01

Samples of cement manufactured in Egypt and the various raw materials, which compose the product, have been analyzed using gamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiological hazard. The mean of specific activity due to all the three radionuclides (226 R a, 232 T h and 40 K ) were found to be 20±4 , 11± 2, 320 ± 18 (gypsum), 41 ±8, 27± 5, 410± 27 (clay), 58 ± 11, 18 3, 321± 20 (Iron ore) and 37.6 ± 6, 11.8 ± 3, 178.6 ± 15 Bq.kg-1 (Portland cement), respectively. 40 K concentration could not be detected in Slag; limestone; Sulphate resistant cement; Clinker and White cement, while the mean activity concentrations of 226 R a and 232 T h are 239 ± 16, 48.7 ± 7; 31.5 ±5, 10 ± 2; 47 ± 7, 20 ± 4; 23 ± 5, 10.4 ± 3 and 23 ± 5, 11 ±3 Bq.kg-1, respectively. The measured activity concentrations of these natural radionuclides were compared with data of some countries. The present values are in the same range and sometimes less than those in other countries

Natural gamma-emitting radionuclides in egyptian cement

International Nuclear Information System (INIS)

El-Arabi, A.M.; Abbady, A.; El-Kamel, A.H.; Nosier, A.; Moustafa, A.

2005-01-01

Samples of cement manufactured in Egypt and the various raw materials, which compose the product, have been analyzed using gamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiological hazard. The mean of specific activity due to all the three radionuclides (226 R a, 232 T h and 40 K ) were found to be 20 ± 4 , 11 ± 2, 320 ± 18 (gypsum), 41 ± 8, 27 ± 5, 410 ± 27 (clay), 58 ± 11, 18 3, 321 ± 20 (Iron ore) and 37.6 ± 6, 11.8 ± 3, 178.6 ± 15 Bq.kg-1 (Portland cement), respectively. 40 K concentration could not be detected in Slag; limestone; Sulphate resistant cement; Clinker and White cement, while the mean activity concentrations of 226 R a and 232 T h are 239 ± 16, 48.7 ± 7; 31.5 ± 5, 10 ± 2; 47 3 ± 7, 20 ± 4; 23 ± 5, 10.4 ± 3 and 23 ± 5, 11 ± 3 Bq.kg-1, respectively. The measured activity concentrations of these natural radionuclides were compared with data of some countries. The present values are in the same range and sometimes less than those in other countries

Studies on influence of environmental factors on concentration on concentration of radionuclides

International Nuclear Information System (INIS)

Anon.

1974-01-01

Environmental factors which seemed to influence the concentration of radionuclides to marine organisms including illumination, water temperature, coexisting stable elements, salt concentration, suspended matters in sea water and residue were studied. The influence of illumination was examined by algae using 137 Cs, 60 Co, 85 Sr, and 106 Ru as tracers, within 24 hours of illumination. The concentration of 137 Cs and 60 Co revealed remarkable increase of uptake in accordance with increasing illumination intensity, and 24 hours illumination showed 2 times concentration of that by 4 hours'. 85 Sr and 106 Ru showed no effect of illumination, and suggested their concentration was depending on adsorption to the surface. As for water temperature, the concentration factor of 65 Zn, 137 Cs obtained from fishes and shells by 22 0 C breeding was 2 times of that by 12 0 C breeding. Concerning the influence of coexisting stable elements, fishes and shells were examined by 54 Mn, 60 Co, and 65 Zn as tracers. When the stable elements concentration in sea water became 10 times the normal, concentration factor depending on adsorption and metabolism became respective one tenth and one second of the normal value. The influence of salt concentration was examined using 85 Sr, 65 Zn, and 137 Cs, and revealed that 28 to 40 per cent changes of salt level gave slight influence on concentration factor. In order to study the influence of suspended matters and quality of residue, 3 kinds of 106 Ru complex species were added. Concentration factor of Hijiki (Hijikia fusiforme) showed no remarkable difference between breeding in filtrated and non-filtrated sea water. However, clams living in the sand should be taken care of the concentration by the residue in the sea bottom. (Kanao, N.)

Contents of natural and anthropological radionuclides in uncultivated soils in the eastern part of Bulgaria

International Nuclear Information System (INIS)

Todorov, P.; Georgieva, D.; Yaneva, B.

2006-01-01

Bulgaria is a country which is located in the Eastern part of Europe. The lay shape of Bulgaria is very various, regarding to the lay shape, rock types and some human activities it defines content of radionuclides in uncultivated soils. Natural radionuclides in these soils are: U 238, Ra 226, Th 232 and K 40. The main anthropological source of radionuclides in these soils is Cs 137. There are no normative documents about limit concentrations of these radionuclides in uncultivated soils. So the actual concentrations are compared with some background concentrations, as a result from a lot of studies in the past. Valuation of natural and anthropological radionuclides is made by determination of their special activity in soil samples from the 0 - 20 cm layer by using the nondestructive gamma spectro metrological analysis. Specific activity of U 238 is defined by its daughter product - Th 234, specific activity of Ra 226 by Pb 214 and Bi 214, of Th 232 by Ac 228 and Pb 212, and specific activity of K-40 and Cs 137 by gamma spectro metrological analysis. In the last years there was made a systematic and valuation of concentrations of these radionuclides. There were examined more than 500 samples each year in the investigated area. Concentrations for U 238 vary from 4 to 64 Bq/kg, for Ra 226 from 7 to 54 Bq/kg, for Th 232 from 12 to 67 Bq/kg, for K 40 from 72 to 1106 Bq/kg. For Cs 137, the concentrations vary from 2 to 234 Bq/kg. During this analysis there were no indices of natural radionuclides above the limit concentrations - background concentrations typical for the different regions

Activation analysis with neutron generators using short-lived radionuclides

International Nuclear Information System (INIS)

Salma, I.

1993-01-01

The short half-life involves a number of important differences in production, transportation and measurement of radionuclides, and in counting statistics as compared with those in traditional activation analysis. Experiments were performed to investigate the analytical possibilities and prospective utilization of short-lived radionuclides produced by 14-MeV neutron irradiation. A rapid pneumatic transfer system for use with neutron generators was installed and applied for detecting radionuclides with a half-life from 300 ms to 30 s. The transport time for samples with a total mass of 1-4 g is between 130 and 160 ms for pressurized air of 0.1-0.4 MPa. 11 elements were studied by the conventional activation method using both a typical pneumatic transport system (run time 3 s) and the fast pneumatic transport facility. The effect of the cyclic activation technique on the elemental sensitivities was also investigated. (orig.)

Exposure to radionuclides in smoke from vegetation fires

International Nuclear Information System (INIS)

Carvalho, Fernando P.; Oliveira, João M.; Malta, Margarida

2014-01-01

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ( 210 Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7255 ± 285 Bq kg −1 , mostly associated with the smaller size smoke particles ( 210 Po in surface air near forest fires displayed volume concentrations up to 70 mBq m −3 , while in smoke-free air 210 Po concentration was about 30 μBq m −3 . The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24 h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from 210 Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of 210 Po, the protection of respiratory tract of fire fighters is strongly recommended. - Highlights: • Natural radionuclides in vegetation are in low concentrations. • Forest fires release natural radionuclides from vegetation and concentrate them in inhalable ash particles. • Prolonged inhalation of smoke from forest fires gives rise enhanced radiation exposure of lungs especially due to polonium. • Respiratory protection of fire fighters and members of public is highly recommended for radioprotection reasons

Production of high-specific activity radionuclides using SM high-flux reactor

International Nuclear Information System (INIS)

Karelin, Ye.A.; Toporov, Yu.G.; Filimonov, V.T.; Vakhetov, F.Z.; Tarasov, V.A.; Kuznetsov, R.A.; Lebedev, V.M.; Andreev, O.I.; Melnik, M.I.; Gavrilov, V.D.

1997-01-01

The development of High Specific Activity (HSA) radionuclides production technologies is one of the directions of RIAR activity, and the high flux research reactor SM, having neutron flux density up to 2.10 15 cm -2 s 1 in a wide range of neutron spectra hardness, plays the principal role in this development. The use of a high-flux reactor for radionuclide production provides the following advantages: production of radionuclides with extremely high specific activity, decreasing of impurities content in irradiated targets (both radioactive and non-radioactive), cost-effective use of expensive isotopically enriched target materials. The production technologies of P-33, Gd-153, W-188, Ni-63, Fe-55,59, Sn-113,117m,119m, Sr- 89, applied in industry, nuclear medicine, research, etc, were developed by RIAR during the last 5-10 years. The research work included the development of calculation procedures for radionuclide reactor accumulation forecast, experimental determination of neutron cross-sections, the development of irradiated materials reprocessing procedures, isolation and purification of radionuclides. The principal results are reviewed in the paper. (authors)

Mobility and Bioavailability of Radionuclides in Soils

International Nuclear Information System (INIS)

Iurian, A.; Olufemi Phaneuf, M.; Mabit, L.

2016-01-01

It is crucial to understand the behavior of radionuclides in the environment, their potential mobility and bioavailability related to long-term persistence, radiological hazards, and impact on human health. Such key information is used to develop strategies that support policy decisions. The environmental behavior of radionuclides depends on ecosystem characteristics. A given soil’s capacity to immobilize radionuclides has been proved to be the main factor responsible for their resulting activity concentrations in plants. The mobility and bioavailability of radionuclides in soils is complex, depending on clay-sized soil fraction, clay mineralogy, organic matter, cation exchange capacity, pH and quantities of competing cations. Moreover, plant species have different behaviors regarding radionuclide absorption depending on soil and plan characteristics

Exposure to radionuclides in smoke from vegetation fires

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Fernando P., E-mail: carvalho@itn.pt; Oliveira, João M.; Malta, Margarida

2014-02-01

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ({sup 210}Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7255 ± 285 Bq kg{sup −1}, mostly associated with the smaller size smoke particles (< 1.0 μm). Depending on smoke particle concentration, {sup 210}Po in surface air near forest fires displayed volume concentrations up to 70 mBq m{sup −3}, while in smoke-free air {sup 210}Po concentration was about 30 μBq m{sup −3}. The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24 h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from {sup 210}Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of {sup 210}Po, the protection of respiratory tract of fire fighters is strongly recommended. - Highlights: • Natural radionuclides in vegetation are in low concentrations. • Forest fires release natural radionuclides from vegetation and concentrate them in inhalable ash particles. • Prolonged inhalation of smoke from forest fires gives rise enhanced radiation exposure of lungs especially due to polonium. • Respiratory protection of fire fighters and members of public is highly recommended for radioprotection reasons.

Assessment of Activity Concentration of Ilmenite and its Contribution to Environment

International Nuclear Information System (INIS)

Syed Asraf Fahlawi Wafa Syed Mohd Ghazi; Ismail Sulaiman; Mohd Rodzi Ali; Rahimah Abdul Rahim; Noraisyah Yusof; Juliana Mahamad Napiah

2014-01-01

Ferum Titanium Oxide (FeTiO 3 ) is the Natural Occurring Radioactive Material (NORM). This mineral contains radionuclides from uranium decay series like Radium-226 ( 226 Ra) and from thorium decay series nuclide like Radium-228 ( 228 Ra) and also from Potassium-40 ( 40 K). This radionuclide in large quantities will increase the radiation exposure risk to mankind and environment. In-situ measurement using scintillation survey meter show that external dose rate at 1 and 0.05 meter from soil surface was 97.0 ± 23.3 and 117 ± 26 nSv/ hour. This figure nearly the same with the average dose rate for Malaysia but higher than world average (UNSCEAR 2000). Monitoring of U and Th concentration from the air show that the result was below detection limit of < 0.0001 Bq/ m 3 . It show that's no radionuclide transfer or migrate to environment. Activity concentration of natural radionuclide of 40 K, 226 Ra, 232 Th and 238 U from the soil was 573 ± 184 Bqkg -1 , 30.6 ± 10.2 Bqkg -1 , 18.8 ± 6.4 Bqkg -1 , and 64.0 ± 34.3 Bqkg -1 . For ilmenite, the activity concentration was 39.0 ± 10.0 Bqkg -1 , 28.0 ± 6.7 Bqkg -1 , 84.0 ± 6.9 Bqkg -1 dan 50.0 ± 7.4 Bqkg -1 for the same natural radionuclide. Effective dose for the public show that the value of 0.17 mSv/ year was lower than the world average effective dose from the natural radioactivity. Radium equivalent for ilmenite and soil was 173 ± 77 and 42.7 ± 0.4 respectively. External Hazard Index is 0.47 ± 0.21 dan 0.36 ± 0.12 for ilmenite and soil. The external radiation hazard index is less than 1, which means it is safe for human to carry out their activities in the area. The estimated cancer risk value was 4.25 x 10 -4 . The probability of increase of cancer risk from the industry is a minor fraction of ICRP values. Event though the result show that the activity from the industry was insignificant to increase the radiation exposure, but all the safety precautions must be follow as per standards and the legislation

Determination of scaling factors to estimate the radionuclide inventory in waste with low and intermediate-level activity from the IEA-R1 reactor

International Nuclear Information System (INIS)

Taddei, Maria Helena Tirollo

2013-01-01

Regulations regarding transfer and final disposal of radioactive waste require that the inventory of radionuclides for each container enclosing such waste must be estimated and declared. The regulatory limits are established as a function of the annual radiation doses that members of the public could be exposed to from the radioactive waste repository, which mainly depend on the activity concentration of radionuclides, given in Bq/g, found in each waste container. Most of the radionuclides that emit gamma-rays can have their activity concentrations determined straightforwardly by measurements carried out externally to the containers. However, radionuclides that emit exclusively alpha or beta particles, as well as gamma-rays or X-rays with low energy and low absolute emission intensity, or whose activity is very low among the radioactive waste, are generically designated as Difficult to Measure Nuclides (DTMs). The activity concentrations of these DTMs are determined by means of complex radiochemical procedures that involve isolating the chemical species being studied from the interference in the waste matrix. Moreover, samples must be collected from each container in order to perform the analyses inherent to the radiochemical procedures, which exposes operators to high levels of radiation and is very costly because of the large number of radioactive waste containers that need to be characterized at a nuclear facility. An alternative methodology to approach this problem consists in obtaining empirical correlations between some radionuclides that can be measured directly – such as 60 Co and 137 Cs, therefore designated as Key Nuclides (KNs) – and the DTMs. This methodology, denominated Scaling Factor, was applied in the scope of the present work in order to obtain Scaling Factors or Correlation Functions for the most important radioactive wastes with low and intermediate-activity level from the IEA-R1 nuclear research reactor. (author)

Seasonal changes on radionuclide concentration in Krusadai Island Mangrove

International Nuclear Information System (INIS)

Valan, I. Inigo; Stephen, A.; Vijayalakshmi, I.; Mathiyarasu, R.; Jose, M.T.

2016-01-01

Krusadai Island: The Biologist's Paradise, is situated in Gulf of Mannar (GOM) near Rameswaram of Tamil Nadu, India. It is an ecological sensitive area and act as the breeding zone for a variety of marine species, most of which are consumed by human population. Govt. of India and Govt. of Tamil Nadu jointly declared GOM as Marine National Park under Wildlife (Protection) Act 1972. So it is essential to have a periodic radiological survey in this area in order to check the concentrations of various radionuclide. Current study is radioactive report on various seasons of 2013 in Krusadai Island Mangrove

The presence of some artificial and natural radionuclides in a Eucalyptus forest in the south of Spain

International Nuclear Information System (INIS)

Vaca, F.; Manjon, G.; Garcia-Leon, M.

2001-01-01

Long-lived artificial radionuclides ( 137 Cs, 90 Sr) were studied in a Eucalyptus plantation located in the south-west of Spain. Radionuclide concentrations were determined in different types of samples corresponding to specific forest components (soil, trees, herbs and litter). Depth profile distributions were obtained in two selected core soils. Two layers were separately measured in three other cores. The concentration factor, defined as the ratio between the mean activity concentration in a component and the mean activity concentration in the soil, was calculated for each component. The biomass of different components was estimated in order to evaluate the total density concentration (Bq/ha) of the artificial radionuclides ( 137 Cs, 90 Sr) in the Eucalyptus plantation. The transfer of the radionuclides between the different forest components can be inferred from the results. Additionally, other naturally occurring radionuclides ( 40 K, 226 Ra, 228 Ra, 228 Ac) were determined for comparison. Transport of radionuclides from forest to a nearby pulp mill is also discussed

Concentration of radionuclides by marine organisms and their food chain

International Nuclear Information System (INIS)

Nakahara, Motokazu

1993-01-01

Accumulation of radionuclides from seawater and from food by marine organisms was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were 57 Co, 95m Tc, 103 Ru, 137 Cs, 65 Zn and 54 Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into non-radioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except 137 Cs and 54 Mn. Retention of 137 Cs and 54 Mn in the organisms one day after feeding of radioactive food was lower than 25 % of the radioactivity dosed. (author)

Exposure to radionuclides in smoke from vegetation fires.

Science.gov (United States)

Carvalho, Fernando P; Oliveira, João M; Malta, Margarida

2014-02-15

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ((210)Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7,255 ± 285 Bq kg(-1), mostly associated with the smaller size smoke particles (fires displayed volume concentrations up to 70 m Bq m(-3), while in smoke-free air (210)Po concentration was about 30 μ Bq m(-3). The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from (210)Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of (210)Po, the protection of respiratory tract of fire fighters is strongly recommended. Copyright © 2013 Elsevier B.V. All rights reserved.

Radionuclide Concentrations in Honey Bees from Area G at TA-54 during 1999

Energy Technology Data Exchange (ETDEWEB)

T. K. Haarmann; P. R. Fresquez

2000-06-01

Honey bees were collected from two colonies located at Los Alamos National Laboratory's Area G, Technical Area 54, and from one control (background) colony located near Jemez Springs, NM. Samples were analyzed for various radionuclides. Area G sample results from both colonies were higher than the upper (95%) level background concentration for {sup 3}H. Sample results from one colony were higher than the upper (95%) level background concentration for total uranium, while sample results from the other colony were higher than the upper (95%) level background concentration for {sup 90}Sr.

Radionuclide Concentrations in Honey Bees from Area G at TA-54 during 1999

International Nuclear Information System (INIS)

Haarmann, T. K.; Fresquez, P.R.

2000-01-01

Honey bees were collected from two colonies located at Los Alamos National Laboratory's Area G, Technical Area 54, and from one control (background) colony located near Jemez Springs, NM. Samples were analyzed for various radionuclides. Area G sample results from both colonies were higher than the upper (95%) level background concentration for 3 H. Sample results from one colony were higher than the upper (95%) level background concentration for total uranium, while sample results from the other colony were higher than the upper (95%) level background concentration for 90 Sr

Radionuclide concentrations and dose assessment of cistern water and groundwater at the Marshall Islands

International Nuclear Information System (INIS)

Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.; Robison, W.L.

1981-01-01

A radiological survey was conducted from September through November of 1978 to determine the concentrations of radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands in the Northern Marshall Islands. More than 70 cistern and groundwater samples were collected at the atolls; the volume of each sample was between 55 and 100 l. The concentration of 90 Sr in cistern water at most atolls is that expected from world-wide fallout in wet deposition. Except for Bikini and Rongelap, 137 Cs concentrations in cistern water are in agreement with the average predicted concentrations from wet deposition. The 239+240 Pu concentrations are everywhere less than the predicted fallout concentrations except at Rongelap, Ailinginae, and Bikini where the measured and predicted concentrations are in general agreement. During the period sampled, most groundwater concentrations of 90 Sr and 137 Cs were everywhere higher than the concentrations in cistern water. Concentrations of the transurancies in filtered groundwater solution were everywhere comparable to or less than the concentrations in cistern water. It is concluded that the concentrations of radionuclides detected during any single period may not necessarily reflect the long-term average concentrations or the concentrations that might be observed if a lined well were extended above the surface. In any case, at all atolls the 90 Sr and 137 Cs concentrations in groundwater are below the concentration guidelines for drinking water recommended by the Environmental Protection Agency. The maximum annual dose rates and the 30- and 50-y integral doses are calculated for the intake of both cistern water and groundwater for each of the atolls

Contamination of soil and food with radionuclides from Chernobyl

International Nuclear Information System (INIS)

Bikit, I.; Slivka, J.; Veskovic, M.; Conkic, Lj.; Krmar, M.

2004-01-01

The results of systematic gamma spectroscopic analyses of fission products performed on the territory of SAP Vojvodina after the Chernobyl accident are presented. Samples of soil grass and food were periodically taken at 5 representative locations and the regions of highest activity concentration are identified on the basis of the results obtained. In the controlled chain soil-plants (feeds)-cow's (milk) on three characteristic locations (soil with different physico-chemical and mechanical properties) the activity concentration of fission radionuclides was determined and transfer factors for soil-plants; feed-milk were calculated. At the territory of hunting sites of SAP Vojvodina, artificial radionuclides were determined in meat and bones of fallow-deer, deer, boar and wild hare; and the highest content of radionuclides was found in meat and bones of boar. (author)

transfer factor of radionuclides from soil-to-palm oil produced

African Journals Online (AJOL)

Ogunjo Samuel

The activity concentration of the natural radionuclides were determined using a single crystal 0.51cm x 0.51cmNaI ... variety of food, cosmetic and hygiene products, and can be .... solubility of the radionuclide that may lead to high uptake or.

Selected natural and fallout radionuclides in plant foods around the Kudankulam Nuclear Power Project, India.

Science.gov (United States)

Ross, E Mahiban; Raj, Y Lenin; Wesley, S Godwin; Rajan, M P

2013-01-01

The activity concentrations of certain radionuclides were quantified in some plant foods cultivated around Kudankulam, where a mega-nuclear power plant is being established. The activity concentrations were found more in the 'pulses' group and were the lowest in 'other vegetable' category. The annual effective dose was computed based on the activity concentration of radionuclides and it was found to be higher due to the consumption of cereals and pulses. Other vegetables, cereals, pulses and nuts recorded high transfer factors for the radionuclide (228)Ra. Fruits, leafy vegetables, tubers and roots, and palm embryo registered high transfer factors for (226)Ra. Group-wise activity concentration, radiation dose to the public and soil-plant-to-transfer factor are discussed in detail. Copyright © 2012 Elsevier Ltd. All rights reserved.

Artificial radionuclides in the atmosphere over Lithuania

International Nuclear Information System (INIS)

Lujaniene, G.; Sapolaite, J.; Remeikis, V.; Lujanas, V.; Aninkevicius, V.

2006-01-01

Systematic observations of radionuclide composition and concentration in the atmosphere have been carried out at the Institute of Physics in Vilnius since 1963. An increase in activity concentration of radionuclides in the atmosphere was observed after nuclear weapon tests and the Chernobyl NPP accident. At present the radiation situation in Lithuania is determined by two main sources of radionuclides, forest fire and resuspension products transferred from highly polluted region of the Ukraine and Belarus. During forest fires the increase in activity concentration of 1 37Cs in the atmosphere was registered in many countries and in Lithuania as well. This work summarizes the experimental data on transport of cesium, plutonium, americium from the highly contaminated territories after the Chernobyl accident. The activity concentrations of 1 37Cs were measured in two - three days samples while plutonium and americium in monthly samples. In addition, the analyses of the events of the increase activity concentration, meteorological situation, speciation of radionuclides and mechanisms of formation and transformation of aerosol carriers of radionuclides are presented. Aerosols were sampled on perchlorvinyl filters and the large volume air samplers with a flow rate from 2400 m 3 /h to about 6000 m 3 /h were used. The radiochemical analyses of monthly samples of aerosol ashes (about 30 g) were performed. For separation of Pu isotopes the TOPO/cyclohexane extraction and radiochemical purification using UTEVA resin were performed, Am was separated after TOPO/cyclohexane extraction using TRU and TEVA resins (100-150 μm). 2 42Pu and 2 43Am were used as tracers in the separation procedure. The alpha spectrometry measurements of Pu and Am isotopes deposited on a stainless steel disc were carried out with the Alphaquattro (Silena) spectrometer. 1 37Cs was determined by gamma-ray spectrometry using the high purity HPGe detector (resolution - 1.9 keV/1.33 Mev, efficiency - 42

Analytical evaluation of the radionuclide concentration through the aquifer for the Abadia de Goias Repository

International Nuclear Information System (INIS)

Alves, Antonio Sergio de Martin

1999-01-01

In this paper the radionuclide concentration though the aquifer has been determined by an analytical process considering that the radionuclide migration is influenced by two kinds of radionuclides releases from the repository during an overflow. In the first release it is assumed that when the radionuclides reach the aquifer there is no contamination in it and the release rate is a constant. For this case it is utilized the model of Reference. For the subsequent releases there will be a contamination in the aquifer provenient from the former releases; it is considered that the subsequent releases are a function of the time which, for the Abadia de Goias Repository, was determined in the Reference. The Laplace transform Method has been utilized to solve the Radionuclide Migration Transport Equation in the aquifer region for the subsequent releases and the resulting function is expressed in terms of exponential and complementary error functions. The improvement in the calculation model, presented in this paper, can be used in the safety analysis of repositories, contributing thus in the nuclear waste management field and particularly, being connecting also to the environmental protection concern. (author)

Dynamic modelling of radionuclide uptake by Fukushima coastal biota - Dynamic modelling of radionuclide uptake by marine biota: application to Fukushima assessment

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, Jordi [Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium)

2014-07-01

Radiological assessments to non-human marine biota are usually carried out by assuming that the activity concentration in an organism is proportional to the activity concentration in an adjacent volume of water, via a concentration factor (CF). It is also assumed that radionuclides in the water are in isotopic equilibrium with the sediments via a sediment distribution coefficient (K{sub d}). These assumptions are not valid in accidental situations where the biota and the sediments react with a time delay to large variations of activity concentration in seawater. A simple dynamic model was developed to factorise the dynamics of radionuclide uptake and turnover in biota and sediments, as determined by a balance between the residence time of radionuclides in seawater/sediments and the biological half-life of elimination in the biota. The model calculates activity concentration of {sup 131}I, {sup 134}Cs, {sup 137}Cs and {sup 90}Sr in seabed sediment, fish, crustaceans, molluscs and macro-algae from surrounding activity concentrations in seawater, with which to derive internal and external dose rates. A central element of this new model is the inclusion of sediment processes in dynamic transfer modelling. The model is adapted to include depletion of radionuclides adsorbed onto suspended particulates (particle scavenging), molecular diffusion, pore water mixing and bioturbation (modelled effectively as a diffusive process) represented by a simple set of differential equations that is coupled with the biological uptake/turnover processes. In this way, the model is capable of reproducing activity concentration in sediment to give a more realistic calculation of the external dose to biota compared with the simpler approach based on CF and K{sub d} values used in previous assessments. The model is applied to the assessment of the radiological impact of the Fukushima accident on marine biota in the early phase of the accident. It is shown that previous assessment of the

Evaluation of maximum radionuclide concentration from decay chains migration in aquifers

International Nuclear Information System (INIS)

Aquino Branco, O.E. de.

1983-01-01

The mathematical formulation of the mechanisms involved in the transport of contaminants in aquifers is presented. The methodology employed is described. A method of calculation the maximum concentration of radionuclides migrating in the underground water, and resulting from one decay chain, is then proposed. As an example, the methodology is applied to a waste basin, built to receive effluents from a hypothectical uranium ore mining and milling facility. (M.A.C.) [pt

Determination of radionuclide concentration of landfill at Eliozu, Port Harcourt, Rivers State

International Nuclear Information System (INIS)

Avwiri, G.O.; Nte, F.U.; Olanrewaju, A.I.

2011-01-01

A survey of the radionuclide concentration from landfill around Eliozu in Port-Harcourt area of River State has been carried out. This study assessed the level of terrestrial gamma radiation and associated dose rates from the naturally occurring radionuclide: 232 Th, 238 U and 40 K. 10 soil and 10 water samples collected from the respective reclaimed part of the Eliozu landfill were analyzed using the gamma-ray spectrometry Nal(TI) detector system. The mean activity concentration for soil was found to be 27.41±9.97Bq/kg for 238 U, 19.27±8.14 Bq/Kg for 232 Th and 326.08±66.74Bq/Kg for 40 K. The average specific activity concentration obtained for 238 U, 232 Th, 40 K for the water samples were 7.92±2.69Bq/l, 6.96±2.37Bq/l and 24.77±8.33 Bq/l. Absorbed dose rates in air outdoors were calculated to be between the range of 23.53nGy.h -1 and 50.39nGy.h -1 with a mean of 38.17±12.45nGy.h -1 for soil and between the range of 6.62nGy.h -1 and 10.71nGy.h -1 with a mean 9.03±3.07nGy.h -1 for water. This value is less than the world average of 55nGy.h -1 for soil. Inhabitants around the landfill are subjected to equivalent radiation exposure (effective dose rate) ranging between 0.2061 and 0.4414mSv.y -1 with a mean of 0.3344±0.1091mSv.y -1 and ranging between 0.0580 and 0.0938mSv.y -1 with a mean of 0.0791±0.0269mSv.y -1 for soil and water. The results comparable to those reported for environment in Nigeria and the world is relatively high due to the presence of medical wastes co-disposed with other wastes in these areas. The results indicated that the observed radiation dose of the terrestrial soils and water from Eliozu reclaimed landfill is minimal and seem to have no high exposure for either inhabitant in and around the landfill.

Radiological hazards of Narghile (hookah, shisha, goza) smoking: activity concentrations and dose assessment

Energy Technology Data Exchange (ETDEWEB)

Khater, Ashraf E.M. [National Center for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt); Physics Department, College of Sciences, King Saud University, P.O. Box 2455, 11451 Riyadh (Saudi Arabia)], E-mail: khater_ashraf@yahoo.com; Abd El-Aziz, Nawal S. [National Center for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt); Al-Sewaidan, Hamed A. [Physics Department, College of Sciences, King Saud University, P.O. Box 2455, 11451 Riyadh (Saudi Arabia); Chaouachi, Kamal [DIU Tobaccology, University of Paris XI-XII (France)

2008-12-15

Narghile (hookah, shisha, goza, 'water-pipe') smoking has become fashionable worldwide. Its tobacco pastes, known as moassel and jurak, are not standardized and generally contain about 30-50% (sometimes more) tobacco, molasses/juice of sugarcane, various spices and dried fruits (particularly in jurak) and, in the case of moassel, glycerol and flavoring essences. Tobacco contains minute amounts of radiotoxic elements such as {sup 210}Pb, {sup 210}Po and uranium, which are inhaled via smoking. Only very few data have been published on the concentrations of natural radionuclides in narghile tobacco mixtures. Consequently, the aim of this study was to draw first conclusions on the potential hazards of radioactivity in moassel tobacco in relation to narghile smoking. The results indicate the existence of a wide range in the radioactivity contents where the average (range) activity concentrations of {sup 238}U, {sup 234}Th {sup 226}Ra, {sup 210}Pb, {sup 210}Po, {sup 232}Th and {sup 40}K, in Bq/kg dry weight were 55 (19-93), 11 (3-23), 3 (1.2-8), 14 (3-29), 13 (7-32), 7 (4-10) and 719 (437-1044) Bq/kg dry weight, respectively. The average concentrations of natural radionuclides in moassel tobacco pastes are comparable to their concentration in Greek cigarettes and tobacco leaves, and lower than that of Brazilian tobacco leaves. The distribution pattern of these radionuclides after smoking, between smoke, ash and filter, is unknown, except for {sup 210}Po during cigarette smoking and from one existing study during moassel smoking. Radiological dose assessment due to intake of natural radionuclides was calculated and the possible radio-toxicity of the measured radionuclides is briefly discussed.

Radionuclides in domestic and imported foods in the United States, 1987-1992

International Nuclear Information System (INIS)

Cunningham, W.C.; Anderson, D.L.; Baratta, E.J.

1994-01-01

Findings from the U.S. Food and Drug Administration's Radionuclides in Foods program are summarized for foods collected between October 1, 1986, and September 30, 1992. Concentrations of radionuclide activity in the Total Diet Study and reactor-survey foods were in Range I or low in Range II of the surveillance and control recommendations of the Federal Radiation Council; no control actions were suggested. Dietary intake of 90 Sr continued the general decline observed since 1961. Approximately 2600 test portions of imported foods were analyzed for contamination associated with the Chernobyl nuclear accident. Concentrations of radionuclide activity were below limits of detection for the vast majority of the imported food test portions but were above the levels of concern for 23 portions. Since 1986, the fraction of imported food test portions having measurable amounts of contamination has steadily declined, as have the average concentrations of radionuclide activity; however, contamination is still occasionally found. Continued monitoring of both domestic and imported foods is planned. 17 refs., 2 figs., 2 tabs

Characteristics of radionuclide contamination of different zones of Semipalatinsk Nuclear Test Site ``Opytnoe pole''

Science.gov (United States)

Kadyrzhanov, K. K.; Khazhekber, S.; Lukashenko, S. N.; Solodukhin, V. P.; Kazachevskiy, I. V.; Poznyak, V. L.; Knyazev, B. B.; Rofer, Ch.

2003-01-01

Data on the spatial distribution of radionuclides (241Am, 239Pu, 137Cs and 152Eu) formed during nuclear explosions of different types near P2 SNTS test site are presented. Radionuclide contamination induced by the explosions varies in the concentrations of individual radionuclides, their proportions and species. Examination of the variations is a crucial task to plan remediation activities as well as those aimed at decrease of radiation risk for population and prevention of repeated contamination. Concentrations of 241Am and 239+240Pu that are the most toxic radionuclides in the area lie in hundred thousands of Bqkg-1. The most contaminated areas are classified by the radionuclide concentration, ratio and form present in soil.

Primordial radionuclides in drinking water from former tin-mining area elevated activity

International Nuclear Information System (INIS)

Adekoya, O. I.; Adewoyin, K. A.; Olaleru, S. A.

2014-01-01

The activity concentrations of the primordial radionuclides in drinking water from two former mining areas (Bisichi and Bukuru) in Jos, Plateau State in Nigeria have been studied. The activities were determined by a non-destructive analysis using a computerized gamma ray spectrometry system with high purity germanium (HPGe). The result show the average activity concentration for 226 Ra, 232 Th and 40 K for Bukuru and Bisichi to be respectively 1.20±0.02 Bq/l, 1.93±0.01 Bq/l, 4.75±0.14 Bq/l and 2.03±0.14 Bq/l, 2.20±0.13 Bq/l, 3.26±0.06 Bq/l. The annual effective doses due to the intake of drinking water from both locations approximately 2.80 mSv and 3.32 mSv respectively. These results are much higher then the reference level of a dose of 0.1 mSv/year from the intake of drinking water.

Measurement of natural and artificial radionuclide concentrations in meat consumed in Hong Kong

International Nuclear Information System (INIS)

Mao, S.Y.; Yu, K.N.

1995-01-01

Radionuclides in meat are determined using the EG and G ORTEC photon spectrometer system. Most of the naturally occurring radionuclides are found to have specific activities below the detectable limit. For our samples, 40 K is found to have values ranging from 295-407 Bq/kg, 172-423 Bq/kg and 172-282 Bq/kg for beef, pork and chicken meat samples, respectively, while 137 Cs has values from 0.19-2 Bq/kg, 0.34-0.71 Bq/kg and 0.12-0.53 Bq/kg, respectively. The estimated weighted committed dose equivalent due to the ingestion of natural radionuclides and 137 Cs in meat is 137 Cs in both sexes are less than the level recommended by the International Commission on Radiological Protection. (author)

Sedimentology models from activity concentration measurements: application to the 'Bay of Cadiz' Natural Park (SW Spain)

International Nuclear Information System (INIS)

Ligero, R.A.; Vidal, J.; Melendez, M.J.; Hamani, M.; Casas-Ruiz, M.

2009-01-01

A previous study on seabed sediments of the Bay of Cadiz (SW of Spain) enabled us to identify several relations between sedimentological variables and activity concentrations of environmental radionuclides such as 137 Cs, 226 Ra, 232 Th and 40 K. In this paper the study has been extended to a large neighbouring inter-tidal area in order to establish if the above mentioned models can be generalized. As a result we have determined that the measured activity concentrations are closely to the values predicted by the theoretical models (correlation coefficient range = 0.85-0.93). Furthermore, the proposal model for granulometric facies as a function of activity concentrations of the abovementioned radionuclides provides for the sediments distribution a representation which agrees with the values of the tidal energy distribution obtained using numeric models calibrated with experimental data from current meters and water level recorders

Radionuclide concentrations in salt pans in the coastal area of Cox's Bazar, Bangladesh

International Nuclear Information System (INIS)

Alam, M.N.; Chowdhury, M.I.; Zafar, M.; Kamal, M.; Ghose, S.; Kamal, A.H.M.

1998-01-01

Radionuclide concentrations of 226 Ra, 232 Th, 137 Cs, 134 Cs and 40 K in samples of water, soil and salt from three gradients of salt pans (reservoir, condenser and crystalliser) in the coastal area of Cox's Bazar, Bangladesh and in samples of refined salts were measured using γ-spectrometry. The activities of 226 Ra in the salt pans were found to be in the range 3·18±1·02 Bq l -1 in water to 25·17±5·76 Bq kg -1 in soil; 232 Th activities were 2·01±0·89 Bq l -1 in water to 42·33±2·54 Bq kg -1 in soil, and 40 K activities ranged from 109·60±27·77 Bq l -1 in water to 651·89±65·89 Bq kg -1 in soil. No 137 Cs or 134 Cs was found in soil, salt and water from the salt pans investigated. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Radionuclide Concentrations in Honey Bees from Area G at TA-54 during 1998

Energy Technology Data Exchange (ETDEWEB)

Haarmann, T.K.; Fresquez, P.R.

1999-06-01

Honey bees were collected from two colonies located at Los Alamos National Laboratory's Area G, Technical Area 54, and from one control (background) colony located near Jemez Springs, NM. Samples were analyzed for various radionuclides. Area G sample results from both colonies were higher than the upper (95%) level background concentration for {sup 239,240}Pu, {sup 3}H, and total uranium. Sample results from one colony were higher than the upper (95%) level background concentration for {sup 238}Pu.

Uptake of radionuclides by vegetation at a High Arctic location

International Nuclear Information System (INIS)

Dowdall, M.; Gwynn, J.P.; Moran, C.; O'Dea, J.; Davids, C.; Lind, B.

2005-01-01

Radionuclide levels in vegetation from a High Arctic location were studied and compared to in situ soil concentrations. Levels of the anthropogenic radionuclide 137 Cs and the natural radionuclides 40 K, 238 U, 226 Ra and 232 Th are discussed and transfer factor (TF) values and aggregated transfer (Tag) values are calculated for vascular plants. Levels of 137 Cs in vegetation generally followed the order mosses > lichen > vascular plants. The uptake of 137 Cs in vascular plants showed an inverse relationship with the uptake of 40 K, with 137 Cs TF and Tag values generally higher than 40 K TF and Tag values. 40 K activity concentrations in all vegetation showed little correlation to associated soil concentrations, while the uptake of 238 U, 226 Ra and 232 Th by vascular and non-vascular plants was generally low. - Uptake of the anthropogenic radionuclide 137 Cs is highest for moss species

New ways in enhancing the vital activity of plants in order to increase crop yields and to suppress radionuclide accumulation

International Nuclear Information System (INIS)

Goncharova, N.; Kislushko, P.; Znebrakova, I.; Matsko, V.

1994-01-01

Soil contamination with long-lived isotopes as a result of Chernobyl nuclear accident necessitates substantially of crop raising procedures. It is found that by optimizing the vital activity processes in plants, is possible to reduce radionuclide uptake. In particular application of Fisher's mineral mix in concentration of 100, 200, 300, g/m 2 to soil decreased the 137 Cs accumulation in green material of lupine (Lupinus luteus L.) 1.1:1.3 and 2.2 times respectively and 1.2:1.1 and 1.1 times, respectively in green material of barley (Hordeum Vulgaris L.). The decrease of 90 Sr accumulation in green material of barley and lupine was similar. On the other hand chloroplasts isolated from showed higher activities of photochemical reactions and the light-dependent ATP enzyme. During the whole growing period of such plants the chlorophyll and protein concentration per wet unit mass were higher than those in control, therefore the high vital activity period in the former case was substantially extended. It has been also found that application of biologically active compounds and trace elements enhances photosynthetic and production activities of plants, reducing level radionuclide accumulation in the harvest. It is found that application of protectants and growth regulators to rye crops also reduces 137 Cs accumulation in green material in booting and earing phases. This finding suggests that this compounds activate the photosynthetic apparatus, reducing level radionuclide accumulation. (author)

Concentrations of Radionuclides (226Ra, 232Th, 40K, and 137Cs) in Chernozems of Volgograd Oblast Sampled in Different Years

Science.gov (United States)

Aparin, B. F.; Mingareeva, E. V.; Sanzharova, N. I.; Sukhacheva, E. Yu.

2017-12-01

Data on the concentrations of natural (226Ra, 232Th and 40K) and artificial (137Cs) radionuclides and on the physicochemical properties of chernozems sampled in different years are presented. In 1952, upon the creation of the Penza-Kamensk state shelterbelt, three deep (up to 3 m) soil pits were examined within the former arable field under two-year-old plantations of ash and maple along the transect crossing the territory of the Beloprudskaya Experimental Station of the USSR Academy of Sciences in Volgograd oblast. The samples from these pits were included into the collection of dated soil samples of the Dokuchaev Central Soil Science Museum. Five pits were examined along the same transect in 2009: three pits under shelterbelts (analogues of the pits studied in 1952) and two pits on arable fields between the shelterbelts. In the past 57 years, certain changes took place in the soil structure, bulk density, and the content and composition of humus. The salt profile of soils changed significantly under the forests. The comparison of distribution patterns of natural soil radionuclides in 1952 and 2009 demonstrated their higher contents at the depth of 10-20 cm in 2009 (except for the western shelterbelt). Background concentrations of natural radionuclides in parent materials and relationships between their distributions and the salt profiles of soils have been determined; they are most clearly observed is the soils under shelterbelts. Insignificant contamination with 137Cs (up to 34 Bq/kg) has been found in the samples of 2009 from the upper (0-20 cm) horizon. The activity of 137Cs regularly decreases from the east to the west; the highest concentrations of this radionuclide are found in the topmost 10 cm. This allows us to suppose that 137Cs was brought with aerial dust by eastern winds, and the shelterbelts served as barriers to the wind flow.

A survey of natural terrestrial and airborne radionuclides in moss samples from the peninsular Thailand.

Science.gov (United States)

Wattanavatee, Komrit; Krmar, Miodrag; Bhongsuwan, Tripob

2017-10-01

The aim of this study was to determine the activity concentrations of natural terrestrial radionuclides ( 238 U, 226 Ra, 232 Th and 40 K) and airborne radionuclides ( 210 Pb, 210 Pb ex and 7 Be) in natural terrestrial mosses. The collected moss samples (46) representing 17 species were collected from 17 sampling localities in the National Parks and Wildlife Sanctuaries of Thailand, situated in the mountainous areas between the northern and the southern ends of peninsular Thailand (∼7-12 °N, 99-102 °E). Activity concentrations of radionuclides in the samples were measured using a low background gamma spectrometer. The results revealed non-uniform spatial distributions of all the radionuclides in the study area. Principal component analysis and cluster analysis revealed two distinct origins for the studied radionuclides, and furthermore, the Pearson correlations were strong within 226 Ra, 232 Th, 238 U and 40 K as well as within 210 Pb and 210 Pb ex , but there was no significant correlation between these two groups. Also 7 Be was uncorrelated to the others, as expected due to different origins of the airborne and terrestrial radionuclides. The radionuclide activities of moss samples varied by moss species, topography, geology, and meteorology of each sampling area. The observed abnormally high concentrations of some radionuclides probably indicate that the concentrations of airborne and terrestrial radionuclides in moss samples were directly related to local geological features of the sampling site, or that high levels of 7 Be were most probably linked with topography and regional NE monsoonal winds from mainland China. Copyright © 2017 Elsevier Ltd. All rights reserved.

Correlation Water Velocity and TSS with Natural Radionuclides Activity

International Nuclear Information System (INIS)

Tri Harningsih; Muzakky; Agus Taftazani

2007-01-01

Correlation water velocity and TSS with natural radionuclides activity has been studied. For that purpose, the study is to correlation water velocity and TSS with radionuclides on water and sediment samples in alongside river Code Yogyakarta. This research selected radionuclides, for examples Ra-226, Pb-212, Ac- 228, and K-40. Election of this radionuclides to spread over gamma gross composition alongside river of Code. Gamma gross influenced by water velocity and TSS, so that require to correct between water velocity and TSS to radionuclides. Sampling water and sediment conducted when dry season of August, 2006 at 11 locations, start from Boyong Bridge until Pacar Bridge. Result of analysis showed that water velocity range from 8-1070 L/dt and TSS range from 2.81 E-06 - 8.02 E-04 mg/L. The accumulation of radionuclides in water samples non correction water velocity for Ra-226: 0.302-2.861 Bq/L, Pb-212: 0.400-3.390 Bq/L, Ac- 228: 0.0029-0.0047 Bq/L and K-40: 0.780-9.178 Bq/L. The accumulation of radionuclide in water samples correction water velocity for Ra-226: 1.112-70.454 Bq/L, Pb-212: 0.850-77.113 Bq/L, Ac-228: 0.7187- 60.859 Bq/L and K-40: 2.420-208.8 Bq/L. While distribution of radionuclide in sediment for the Ra-226: 0.0012-0.0211 Bq/kg, Pb-212: 0.0017-0.0371 Bq/kg, Ac-228: 0.0021-0.0073 Bq/kg and K-40: 0.0006-0.0084 Bq/kg. (author)

Investigations of 90Sr Activity Concentrations in Animal Bones in Republic of Croatia

International Nuclear Information System (INIS)

Maracic, M.; Franic, Z.; Marovic, G.

2008-01-01

The paper presents investigations of 90Sr activity concentrations in long bones of some domestic animals (cows, pigs, lambs) collected over the last ten years in the Republic of Croatia. The investigations are a part of an extended and still ongoing monitoring programme of radioactive contamination of human environment of Croatia. Bone is critical organ for the accumulation of many radionuclides, including 90Sr, a highly toxic radionuclide, similar to calcium in its chemical behaviour and metabolic processes. It has been found that the 90Sr activity concentrations in bones differ between respective animal species, the highest activity concentrations being found in lamb bones in year 2005 (472.61 mBqgCa -1 or 2.14 Bqkg -1 ). In cow bones highest value being found was in 1998, being 611.42 mBqgCa -1 or 69.09 Bqkg -1 90Sr. The transient increases and decreases in 90Sr activity concentrations in bones can be partially explained by a variety of environmental physical and biochemical factors that naturally fluctuate. As the levels of stable strontium in bone tissue is strongly correlated to calcium content of bone, 90Sr can be used as efficient radiotracer of stable strontium, which is itself important since it positively affects bone metabolism promoting bone formation and decreasing bone resorption, leading to normalized bone density.(author)

Radionuclides in plants in urban areas

International Nuclear Information System (INIS)

Todorovic, D.; Ajtic, J.; Popovic, D.; Nikolic, J.

2009-01-01

The results of a long-term study (from 2002 to 2008) on the concentrations of natural ( 7 Be, 210 Pb, 40 K) and fission ( 137 Cs) radionuclides in leaves of higher plants (linden and chestnut) in an urban area (city of Belgrade) are presented. The activity of the radionuclides was determined on an HPGe detector by standard gamma spectrometry. The study is a part of the ongoing air quality monitoring programme in urban areas in the Republic of Serbia. (author) [sr

Activity concentrations of primordial radionuclides in sediments of surface - water dams in southwest Nigeria - a baseline survey; Concentrations des activites des radionucleides primordiaux dans les sediments des retenues des eaux de ruissellement dans le sud-ouest du Nigeria. Etude de reference

Energy Technology Data Exchange (ETDEWEB)

Isinkaye, M.O. [University of Ado-Ekiti, Dept. of Physics (Nigeria); Farai, I.P. [Ibadan Univ., Dept. of Physics (Nigeria)

2008-10-15

The radionuclide contents of sediment samples collected from 20 surface-water dams in southwestern Nigeria have been determined by low-level gamma-spectroscopy. The average concentration of {sup 40}K in each of the dams varied between 110.9{+-}11.9 Bq kg-1 and 1025.9{+-}36.8 Bq kg{sup -1} with an overall mean ({+-}SD) of 549.3 {+-} 247.6 Bq kg{sup -1} while that of {sup 238}U varied from 17.1{+-}3.6 to 51.9{+-}8.7 Bq kg{sup -1} with an overall mean ({+-}SD) of 27.6{+-}8.5 Bq kg{sup -1} and that of {sup 232}Th varied from 26.2 {+-}3.6 Bq kg{sup -1} to 130.1{+-}23.7 Bq kg{sup -1} with overall mean ({+-}SD) of 62.0{+-}26.1 Bq kg{sup -1}. The variability of the values shows the wide disparity in the measured activity concentrations. The mean radium equivalent of 158.9 Bq kg{sup -1} was calculated for the sediments in the dams. No artificial gamma emitting radionuclide was detected in the samples. (authors)

Extreme radionuclide accumulation on alpine glaciers in cryoconites

International Nuclear Information System (INIS)

Lettner, H.; Wilflinger, T.; Hubmer, A.K.; Bossew, P.

2008-01-01

Full text: Under environmental conditions when radionuclide fallout will not be diluted by media like soil or water, radionuclides deposited may accumulate to unusual high activities. On glacier surfaces conditions as such exist for aerosols and airborne dust deposited with anthropogenic and natural radionuclides attached on their surfaces. In the course of agglomeration processes initiated by melting and redistribution, these particles may concentrate in small depressions, ice pockets, ablation edges etc. and form substances called cryoconites ('ice dust'). As there is no other matrix than the original aerosol particles, cryoconites are a sink for radionuclides and airborne pollutants and their activity levels are among the highest produced by natural processes observed in environmental media. 137 Cs activities found on glaciers in the Austrian alps are between 255 and 136.000 Bq/kg and predominantly derived from Chernobyl, but also from global fallout. Further anthropogenic radionuclides detected are 134 Cs, 90 Sr, 238,239+240 Pu, 241 Am, 125 Sb, 154 Eu, 60 Co and 207 Bi. In combination with the naturally occurring radionuclides 7 Be and 210 Pb and isotopic ratios such as 134 Cs/ 137 Cs, identification and discrimination of the sources, the nuclear weapon tests and the Chernobyl fallout, can be carried out. (author)

The vertical distribution of radionuclides in a Ribble Estuary saltmarsh: transport and deposition of radionuclides

International Nuclear Information System (INIS)

Brown, J.E.; McDonald, P.; Parker, A.; Rae, J.E.

1999-01-01

Routine discharges of low-level liquid radioactive waste by British Nuclear Fuels plc (BNFL) at Sellafield and Springfields have resulted in enhanced levels of radionuclides in sediments of the Ribble Estuary, NW England, UK. Variations in radionuclide concentrations ( 137 Cs, 230 Th, and 239240 Pu) with depth in a mature saltmarsh core were analysed in order to investigate historical discharge trends and waste-dispersal mechanisms. Core samples from Longton/Hutton Marsh were analysed by gamma-spectrometry and α-spectrometry for radionuclides and by laser granulometry to establish grain-size variations with depth. Distinct subsurface maxima were present for 137 Cs and 239240 Pu with activities as high as 4500 Bq kg -1 for 137 Cs and 600 Bq kg -1 for 239240 Pu. Thorium-230 exhibited complex activity profiles with depth, specific activities ranging between 200 and 2400 Bq kg -1 . The vertical distributions of Sellafield-derived radionuclides ( 137 Cs and 239240 Pu) in mature saltmarsh deposits reflect the time-integrated discharge pattern from Sellafield, implying a transport mechanism that has involved the mixing of sediment labelled with radioactivity from recent discharges and sediment labelled from historical discharge events before deposition. A mechanism involving the transport of contaminated silt therefore seems to dominate. The vertical distribution of Springfields-derived 230 Th in the same areas reflects the annual gross-α discharge pattern from BNFL Springfields. In contrast to the Sellafield-derived radionuclides, a fairly rapid transport mechanism from source to sink is implied, with little or no time for mixing with radionuclides discharged years earlier. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Investigation of the fluctuation range of activity concentrations of natural radionuclides in surface air

International Nuclear Information System (INIS)

Winkler, R.; Hoetzl, H.

1985-01-01

Daily and seasonal concentration fluctuations of short-lived Rn fission products observed and the seasonal and long-term concentration fluctuations of Pb-210, Po-210, Ra-226, Ra-228, K-40 and Be-7 are discussed; the frequency distributions of the concentration values are illustrated. For a period of several years, the following mean values of activity concentrations were found (μBq/m 3 ): Pb-210: 600 Ra-226: 1.3 K-40: 13, Po-210: 33 Ra-228: 0.5 Be-7: 3700. In accordance with the origin from the soil, there is a significant correlation between the respective activity concentration and air-borne dust concentration for Ra-226, Ra-228, and K-40. The investigation revealed a most significant correlation between the Pb-210 concentration and the stagnancy index, the latter being a measure for the degree of blending of the surface layer of air. The resuspension factors found for Ra-226 and Pb-210 are discussed. (orig./HP) [de

The biotic factors role in radionuclide migration of natural-vegetable complexes

International Nuclear Information System (INIS)

Yakushev, B.I.; Kazej, A.I.; Sak, M.M.; Kuz'mich, O.T.; Golushko, R.M.

1992-01-01

In Byelorussiyn from first months after the Chernobyl' accident investigation are conducting on the radionuclide de dynamics in the soil-plant-soil system. The isotope composition of soil contamination density and specific plants radioactivity are studying, the radionuclide migration dynamic through the soil profile is investigating. The data are shown on considerable reduction of the plants radioactivity (1986-91 years) in connection with the reduction in the soil contamination density with gamma-spectrum radionuclides, accounting for Ce-144, Pr-144, Ru-106, Cs-134 decay; information is done on gamma-spectrum radionuclides of organs in natural pine and meadows system. It is shown, that the radionuclides are actively absorbed by roots in a zone of the highest radionuclide concentration and are delivered into the overground plant parts, then actively are removed into environment in the breathing process. 11 refs.; 4 tabs

Separation of radionuclides from gas by sorption on activated charcoal and inorganic sorbents

International Nuclear Information System (INIS)

Kepak, F.

1988-01-01

The review deals with the sorption and ion exchange of gaseous radionuclides on activated charcoal and on inorganic sorbents. It presents the physical and chemical characteristics of radionuclides, the sources of gaseous forms of radionuclides as well as the composition of radioactive gases from some nuclear facilities. 79 refs. (author)

Forage uptake of uranium series radionuclides in the vicinity of the anaconda uranium mill

International Nuclear Information System (INIS)

Rayno, D.R.; Momeni, M.H.; Sabau, C.

1980-01-01

Radiochemical analysis was performed on samples of soil and eight species of common vegetation growing on the Anaconda uranium mill site, located in New Mexico. The concentrations of the long-lived radionuclides U-238, U-234, Th-230, Ra-226, and Pb-210 in these forage plants were determined. The sampling procedures and analytical laboratory methods used are described. The highest radionuclide concentration found in a forage species was 130 pCi of Ra-226 per gram dry weight for grass growing on the main tailings pile at Anaconda, where the surface soil activity of Ra-226 was 236 pCi/g. A comparison of shoots activity with that of roots and soil was used to determine a distribution index and uptake coefficient for each species. The distribution index, the ratio of root activity to shoot activity, ranged from 0.30 (Th-230) in galleta grass (Hilaria jamesii) to 38.0 (Ra-226) in Indian ricegrass (Oryzopsis hymenoides). In nearly all instances, the roots contained higher radionuclide concentrations. The uptake coefficient, the ratio of vegetation activity to soil activity, ranged from 0.69 (U-238) in Indian ricegrass roots to 0.01 (U-238) in four-wing saltbush (Atriplex canescans) shoots. The range of radionuclide concentrations in plants growing on the Anaconda mill site is compared to that in vegetation from a control site 20 km away

Annual limits on intake for members of the public and derived reference levels of radionuclide concentrations in the environment

International Nuclear Information System (INIS)

Mason, G.C.

1983-01-01

A proposal is presented recommending the introduction in Australia of Annual Limits on Intake of radionuclides for members of the public and of corresponding reference levels of radionuclide concentrations in the environment. The proposal is related to recent recommendations of the International Commission on Radiological Protection and draft recommendations under consideration by the International Atomic Energy Agency

Activity Concentration for Surface Soil Samples Collected from Arrant, Qena, Egypt

International Nuclear Information System (INIS)

Harb, S.; Salahel Din, K.; Abbady, A.; Moustafa, M.

2010-01-01

Soil samples were collected from four regions from Armant area. Qena, Upper Egypt for measure their natural radioactivity concentrations due to Ra-226, Th-232 and K-40 radionuclides. Thirty-Four surface soil samples were analyzed by using low-level gamma-spectrometric analysis. The average activity concentration for Ra-226 in (Bq/kg) in the collected soil samples were found to be 27.3 ±3.2, 11.4±1.09, 10.6±1.2, and 11.4±1.02 while the average value for Th-232 were 15.1±1.4, 11.1±0.77, 10.8 ± 0.72 and 11.1 ± 0.8 (Bq/kg) for soil samples from North, South, West and East. The corresponding average values for K-40 were 521.4±16.8, 463±14.8, 488.9±15.6 and 344.5±10.7 (Bq/kg), respectively. Based on radionuclides concentration in surface soil samples the radiological effects can be assessed

Airborne radionuclides in the proglacial environment as indicators of sources and transfers of soil material.

Science.gov (United States)

Łokas, Edyta; Wachniew, Przemysław; Jodłowski, Paweł; Gąsiorek, Michał

2017-11-01

A survey of artificial ( 137 Cs, 238 Pu, 239+240 Pu, 241 Am) and natural ( 226 Ra, 232 Th, 40 K, 210 Pb) radioactive isotopes in proglacial soils of an Arctic glacier have revealed high spatial variability of activity concentrations and inventories of the airborne radionuclides. Soil column 137 Cs inventories range from below the detection limit to nearly 120 kBq m -2 , this value significantly exceeding direct atmospheric deposition. This variability may result from the mixing of materials characterised by different contents of airborne radionuclides. The highest activity concentrations observed in the proglacial soils may result from the deposition of cryoconites, which have been shown to accumulate airborne radionuclides on the surface of glaciers. The role of cryoconites in radionuclide accumulation is supported by the concordant enrichment of the naturally occurring airborne 210 Pb in proglacial soil cores showing elevated levels of artificial radionuclides. The lithogenic radionuclides show less variability than the airborne radionuclides because their activity concentrations are controlled only by the mixing of material derived from the weathering of different parent rocks. Soil properties vary little within and between the profiles and there is no unequivocal relationship between them and the radionuclide contents. The inventories reflect the pathways and time variable inputs of soil material to particular sites of the proglacial zone. Lack of the airborne radionuclides reflects no deposition of material exposed to the atmosphere after the 1950s or its removal by erosion. Inventories above the direct atmospheric deposition indicate secondary deposition of radionuclide-bearing material. Very high inventories indicate sites where transport pathways of cryoconite material terminated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Up-to-date concentrations of long-lived artificial radionuclides in the Tom and Ob rivers in the area influenced by discharges from Siberian chemical combine

International Nuclear Information System (INIS)

Nikitin, A.I.; Kryshev, I.I.; Bashkirov, N.I.; Valetova, N.K.; Dunaev, G.E.; Kabanov, A.I.; Katrich, I.Yu; Krutovsky, A.O.; Nikitin, V.A.; Petrenko, G.I.; Polukhina, A.M.; Selivanova, G.V.; Shkuro, V.N.

2012-01-01

The Siberian Chemical Combine (SCC) is located in Seversk (formerly known as Tomsk-7) in the Tomsk Region of the Russian Federation. The main contribution of radionuclides in the SCC process water discharged into the Tom River was from the single-pass reactors, now removed from service (the last SCC reactor was shutdown on June 5, 2008). The data on the concentrations of 90 Sr, 137 Cs, 239,240 Pu and other artificial radionuclides in water, bottom sediments and flood-plain soils of the Tom and Ob rivers from Tomsk to the confluence of the rivers, are presented and discussed. The results of measurements carried out after shutdown of the last SCC single-pass reactor indicated no radiologically significant consequences of SCC activities for the studied water environment compartments. Contemporary activity concentrations of long-lived artificial radionuclides 3 H, 90 Sr, 137 Cs and 239,240 Pu in river water were below the intervention levels established by current regulations of the Russian Federation for these radionuclides. The results of 3 H analysis in water from the Tom and Samuska rivers demonstrated no inflow of contaminated formation water to surface water from the sites where liquid radioactive wastes of the SCC were injected below the surface. However, the density of flood-plain soil contamination by long-lived 137 Cs in the area influenced by SCC liquid discharges was higher than regional technogenic background. There were local flood-plain areas contaminated not only by 137 Cs, but also other gamma-emitters, such as 60 Co and 152 Eu.

Correlations of natural radionuclides in soil with those in sediment from the Danube and nearby irrigation channels

International Nuclear Information System (INIS)

Krmar, M.; Varga, E.; Slivka, J.

2013-01-01

The correlation between activity concentrations of some natural radionuclides ( 238 U, 226 Ra, 232 Th, 40 K) measured in soil and in sediment taken from the Danube River and nearby irrigation channels was studied. The soil samples were collected from the northern part of Serbia and the sediment from the Serbian part of the Danube River and from the surrounding irrigation channels. The correlation between 238 U and other natural radionuclides in irrigation channel sediments was not as good as in the Danube. One of the possible explanations for this weak correlation can be the different chemical dynamics of 238 U in the irrigation channel sediment or changes of the 238 U activity concentration in irrigation channel sediment due to some human activities. The evaluation of ratios of activity concentrations of some natural radionuclides could be a more sensitive method for the determination of contaminant, rather than the straightforward analysis of activity concentrations. -- Highlights: ► 238 U, 232 Th and 40 K were measured in soil, Danube and surrounding channel sediment. ► Correlation of activity concentrations were observed. ► In cannel sediment natural radionuclides are not well correlated as in Danube one. ► Ratios of 238 U, 232 Th and 40 K can be good indicator for TENORM monitoring

Radionuclide concentrations in game and nongame fish upstream and downstream of Los Alamos National Laboratory: 1981 to 1993

International Nuclear Information System (INIS)

Fresquez, P.R.; Armstrong, D.R.; Salazar, J.G.

1994-08-01

Radionuclide concentrations were determined in game (surface-feeding) and nongame (bottom-feeding) fish collected from reservoirs upstream (Abiquiu, Heron, and El Vado) and downstream (Cochiti) of Los Alamos National Laboratory from 1981 to 1993. The average levels of 90 Sr, 137 Cs, 238 Pu, and 239 Pu in game and nongame fish collected from Cochiti reservoir were not significantly different in fish collected from reservoirs upstream of the Laboratory. Total uranium was the only radionuclide that was found to be significantly higher n both game and nongame fish from Cochiti as compared to fish from Abiquiu, Heron, and El Vado. Uranium concentrations in fish collected from Cochiti, however, significantly decreased from 1981 to 1993, and no evidence of depleted uranium was found in fish samples collected from Cochiti in 1993. Based on the average concentration of radionuclides over the year the effective (radiation) dose equivalent from consuming 46 lb of game fish and nongame fish from Cochiti reservoir after natural background has been subtracted was 0.005 and 0.009 mrem/yr, respectively. The highest dose was <0.01% of the International Commission on Radiological Protection (ICRP) permissible dose limit for protecting members of the public

Radionuclides in waters and soil near the Lagoa Real uranium mine

International Nuclear Information System (INIS)

Souza, Susana Oliveira de; Freire, Fabinara Dantas; Dias, Dario M.; Veiga, Artur Jose Pires

2015-01-01

Uranium mining generates fuel for the nuclear power plants and it is the main source of income for the region of Caetite-BA. However, Non-Governmental Organizations claim that mining pollutes the environment and jeopardizes human health and safety. Besides uranium, the ground contains significant concentrations of thorium and of all radionuclides of its family, such as radium isotopes. In this framework, we carried out an independent study analyzing the concentration of the radionuclides activities 226, 228 Ra and 234,238 U in water samples and radionuclides 226 Ra, 232 Th and 40 K in soil samples using different techniques of nuclear spectrometry. The selection criteria for the collection points were their proximity to the uranium processing plant and to affluent rivers. The soil samples presented very low concentration of activity for radionuclides investigated, compared to the limits established of the exclusion, exemption and impartiality for radiation protection requirement given by the Regulator Position established by CNEN. The amount of radioisotopes appears consistent with a natural origin, thus it is not possible to state that the mining process in Caetite increases pollution or radiation exposure in a significant way. (author)

Radionuclides in waters and soil near the Lagoa Real uranium mine

Energy Technology Data Exchange (ETDEWEB)

Souza, Susana Oliveira de; Freire, Fabinara Dantas, E-mail: sosouza@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Fisica; Kozlowska, Beata; Walencik-Lata, Agata, E-mail: beata.kozlowska@us.edu.pl [University of Silesia, Institute of Physics, Katowice (Poland); Dias, Dario M., E-mail: engenheirodario@gmail.com [Secretaria Municipal de Meio Ambiente e Turismo, Andarai, BA (Brazil); Veiga, Artur Jose Pires, E-mail: tk1@ibest.com [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA (Brazil). Departamento de Ciencias Exatas e Tecnologicas

2015-07-01

Uranium mining generates fuel for the nuclear power plants and it is the main source of income for the region of Caetite-BA. However, Non-Governmental Organizations claim that mining pollutes the environment and jeopardizes human health and safety. Besides uranium, the ground contains significant concentrations of thorium and of all radionuclides of its family, such as radium isotopes. In this framework, we carried out an independent study analyzing the concentration of the radionuclides activities {sup 226,} {sup 228}Ra and {sup 234,238}U in water samples and radionuclides {sup 226}Ra, {sup 232}Th and {sup 40}K in soil samples using different techniques of nuclear spectrometry. The selection criteria for the collection points were their proximity to the uranium processing plant and to affluent rivers. The soil samples presented very low concentration of activity for radionuclides investigated, compared to the limits established of the exclusion, exemption and impartiality for radiation protection requirement given by the Regulator Position established by CNEN. The amount of radioisotopes appears consistent with a natural origin, thus it is not possible to state that the mining process in Caetite increases pollution or radiation exposure in a significant way. (author)

Activity determination of radionuclides for diagnostic and therapy

International Nuclear Information System (INIS)

Kossert, Karsten

2013-01-01

The application of radionuclides plays in medicine an important role and requires reliable activity determination. The PTB provides for this activity normals and determines the activity of the presented sources. The article describes, how activity determinations in the PTB occur, and by which ways this can be used for nuclear medicine. Research and development works in the PTB are just so illuminated as the determination of nuclide data of some isotopes relevant for medicine.

Radionuclide analysis in the soil of Kumaun Himalaya, India, using gamma ray spectrometry

International Nuclear Information System (INIS)

Ramola, R.C.; Prasad, Ganesh; Gusain, G.S.; Choubey, V.M.; Tosheva, Z.; Kies, A.

2011-01-01

Environmental release of low levels of radioactivity can occur as a consequence of normal radionuclides present in the earth's crust. We present here the results of a survey undertaken in 2003 on the radionuclide concentration in different rock formations in the eastern part of Kumaun Himalaya. The activity concentration and gamma-absorbed dose rates of the terrestrial radionuclides caused by 226 Ra, 232 Th and 40 K were determined in the soil samples collected from the eastern part of Kumaun Himalaya. The mean concentration of 238 U and 232 Th in the earth's crust varied from 0.5 to 5 ppm (6 to 60 Bq/kg) and 2 to 20 ppm (8 to 80 Bq/kg) respectively. The reported activity concentration for the different rock formations varied from 32.6 to 1305.5 Bq/kg for 238 U, 16.3 to 136.3 Bq/kg for 232 Th and 124.6 to 1758.0 Bq/kg for 40 K. The distribution of the radionuclides varied with rock type due to different chemical properties of the measured radionuclides and the rocks. The result shows that high activity levels were found in Saryu Formation consisting of augen-gneiss, granite interbedded with schists and flaggy quartzite. The total air-absorbed dose rate in air above 1 m height was calculated from the three radionuclides ( 226 Ra, 232 Th and 40 K), which varied from 39.1 to 226.8 nGy h -1 . The internal and external health-hazard indices were calculated based on the concentration of 226 Ra, 232 Th and 40 K. Strong positive correlations were observed between 235 U and 226 Ra, 232 Th and 226 Ra, 40 K and 232 Th as well as 40 K and 226 Ra. However, no significant correlation was observed between 238 U and 226 Ra because of radioactive disequilibrium between them. (author)

Natural-series radionuclides in traditional North Australian aboriginal foods

International Nuclear Information System (INIS)

Murray, A.S.; Johnston, A.; Hancock, G.J.; Martin, P.

1997-01-01

Activity concentrations of the radionuclides 226 Ra, 210 Pb, 210 Po, 238 U, 234 U, 230 Th, 232 Th and 227 Ac were measured in edible flesh of traditional Aboriginal food items from the Magela and Cooper Creek systems in the tropical Northern Territory of Australia. Fish, buffalo, pig, magpie goose, filesnake, goanna, turtle, freshwater shrimp and freshwater crocodile were studied. Activity concentrations in water were also measured to enable the calculation of concentration ratios (CRs).For most edible flesh samples, activity concentrations followed the approximate order: 210 Po>> 226210 [ 234 Usimilar 238 [ 230 Thsimilar 232 Th]. The 210 Po/ 210 Pb activity ratio was particularly high (greater than 100) for pig flesh. CRs for fish species fall into two groups. Group 1 (bony bream and sleepy cod) had CRs about five times higher than for group 2 (eight other species). CRs for turtle flesh were similar to those for fish in group 1, while those for turtle liver were about a factor of 10 higher. CRs for magpie goose, filesnake, freshwater shrimp, goanna and crocodile flesh were also of the same order as for fish in groups 1 or 2.Calculations of dose resulting from release of wastewaters from uranium mining operations in the region show that the dominant pathway would be uptake of radionuclides, especially 226 Ra, by freshwater mussels, followed by radionuclide uptake by fish. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

Long-term development of the radionuclide exposure of murine rodent populations in Belarus after the Chernobyl accident.

Science.gov (United States)

Ryabokon, N I; Smolich, I I; Kudryashov, V P; Goncharova, R I

2005-12-01

As a determinant of the associated health risks, the behavior of radionuclides in natural ecosystems needs to be better understood. Therefore, the activity concentration of various long-lived radionuclides released due to the Chernobyl accident, and the corresponding contributions to the whole-body dose rate, was studied as a function of time in mammalian indicator species inhabiting the natural forest ecosystems of Belarus, the bank vole (Clethrionomys glareolus) and the yellow-necked mouse (Apodemus flavicollus). The activity concentrations of 137Cs, 134Cs, 90Sr, 238Pu, 239,240Pu, 241Pu and 241Am in soil and in animals were measured at five monitoring sites with different ground deposition of radionuclides at different distances from the destroyed reactor. The observed temporal pattern of the radionuclide activity concentration in the studied animal populations reflects the changes in biological availability of these isotopes for biota, mostly due to fuel particle destruction and appearance of dissolved and exchangeable forms of radionuclides. The time course of 134+137Cs activity concentrations in animal populations appeared as a sequence of increase, peak and decrease. Maximal levels of radiocesium occurred 1-2 years after deposition, followed by an exponential decrease. Concentrations of incorporated 90Sr increased up to the tenth year after deposition. The activity concentrations of transuranic elements (238Pu, 239,240Pu, 241Pu and 241Am) were much lower than those of the other radionuclides, in the studied animals. A considerable activity of 241Am in animals from areas with high levels of contamination was firstly detected 5 years after deposition, it increased up to the tenth year and is expected to increase further in the future. Maximal values of the whole-body absorbed dose rates occurred during the year of deposition, followed by a decrease in the subsequent period. Generally, this decrease was monotonic, mainly determined by the decrease of the

Measurement of radionuclide activities of uranium-238 series in soil samples by gamma spectrometry: case of Vinaninkarena

International Nuclear Information System (INIS)

Randrianantenaina, F.R.

2017-01-01

The aim of this work is to determine the activity level of radionuclides of uranium-238 series. Eight soil samples are collected at Rural Commune of Vinaninkarena. After obtaining secular equilibrium, these samples have been measured using gamma spectrometry system in the Nuclear Analyses and Techniques Department of INSTN-Madagascar, with HPGe detector (30 % relative efficiency) and a Genie 2000 software. Activities obtained vary from (78±2)Bq.kg -1 to (49 231 ± 415)Bq.kg -1 . Among these eight samples, three activity levels are shown. Low activity is an activity which has value lower or equal to (89±3)Bq.kg -1 . Average activity is an activity which has value between (186± 1)Bq.kg -1 and (1049 ±7)Bq.kg -1 . And high activity is an activity which has value higher or equal to (14501±209)Bq.kg -1 . According to UNSCEAR 2000, these value are all higher than the world average value which is 35 Bq.kg -1 .It is due to the localities of sampling points. The variation of the activity level depends on radionuclide concentration of uranium-238 series in the soil. [fr

Uptake, depuration, and radiation dose estimation in zebrafish exposed to radionuclides via aqueous or dietary routes

Energy Technology Data Exchange (ETDEWEB)

Reinardy, Helena C., E-mail: helena.reinardy@plymouth.ac.uk [Ecotoxicology Research and Innovation Centre, School of Biomedical and Biological Sciences, The University of Plymouth (United Kingdom); Teyssie, Jean-Louis, E-mail: J.Teyssie@iaea.org [IAEA Marine Environment Laboratories, 4, Quai Antoine 1er, MC 98000 (Monaco); Jeffree, Ross A., E-mail: R.Jeffree@iaea.org [IAEA Marine Environment Laboratories, 4, Quai Antoine 1er, MC 98000 (Monaco); Faculty of Science, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007 (Australia); Copplestone, David, E-mail: David.copplestone@stir.ac.uk [School of Biological and Environmental Sciences, University of Stirling (United Kingdom); Henry, Theodore B., E-mail: ted.henry@plymouth.ac.uk [Ecotoxicology Research and Innovation Centre, School of Biomedical and Biological Sciences, University of Plymouth (United Kingdom); Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996 (United States); Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996 (United States); Jha, Awadhesh N., E-mail: A.Jha@plymouth.ac.uk [Ecotoxicology Research and Innovation Centre, School of Biomedical and Biological Sciences, The University of Plymouth (United Kingdom)

2011-09-01

Understanding uptake and depuration of radionuclides in organisms is necessary to relate exposure to radiation dose and ultimately to biological effects. We investigated uptake and depuration of a mixture of radionuclides to link bioaccumulation with radiation dose in zebrafish, Danio rerio. Adult zebrafish were exposed to radionuclides ({sup 54}Mn, {sup 60}Co, {sup 65}Zn, {sup 75}Se, {sup 109}Cd, {sup 110m}Ag, {sup 134}Cs and {sup 241}Am) at tracer levels (< 200 Bq g{sup -1}) for 14 d, either via water or diet. Radioactivity concentrations were measured in whole body and excised gonads of exposed fish during uptake (14 d) and depuration phases (47 d and 42 d for aqueous and dietary exposures respectively), and dose rates were modelled from activity concentrations in whole body and exposure medium (water or diet). After 14-day aqueous exposure, radionuclides were detected in decreasing activity concentrations: {sup 75}Se > {sup 65}Zn > {sup 109}Cd > {sup 110m}Ag > {sup 54}Mn > {sup 60}Co > {sup 241}Am > {sup 134}Cs (range: 175-8 Bq g{sup 1}). After dietary exposure the order of radionuclide activity concentration in tissues (Bq g{sup -1}) was: {sup 65}Zn > {sup 60}Co > {sup 75}Se > {sup 109}Cd > {sup 110m}Ag > {sup 241}Am > {sup 54}Mn > {sup 134}Cs (range: 91-1 Bq g{sup -1}). Aqueous exposure resulted in higher whole body activity concentrations for all radionuclides except {sup 60}Co. Route of exposure did not appear to influence activity concentrations in gonads, except for {sup 54}Mn, {sup 65}Zn, and {sup 75}Se, which had higher activity concentrations in gonads following aqueous exposure. Highest gonad activity concentrations (Bq g{sup -1}) were for {sup 75}Se (211), {sup 109}Cd (142), and {sup 65}Zn (117), and highest dose rates ({mu}Gy h{sup -1}) were from {sup 241}Am (aqueous, 1050; diet 242). This study links radionuclide bioaccumulation data obtained in laboratory experiments with radiation dose determined by application of a dosimetry modelling tool, an

Radionuclides in drinking water: the recent legislative requirements of the European Union

International Nuclear Information System (INIS)

Grande, Sveva; Risica, Serena

2015-01-01

In November 2013, a new EURATOM Directive was issued on the protection of public health from the radionuclide content in drinking water. After introducing the contents of the Directive, the paper analyses the hypotheses about drinking water ingestion adopted in documents of international and national organizations and the data obtained from national/regional surveys. Starting from the Directive’s parametric value for the Indicative Dose, some examples of derived activity concentrations of radionuclides in drinking water are reported for some age classes and three exposure situations, namely, (i) artificial radionuclides due to routine water release from nuclear power facilities, (ii) artificial radionuclides from nuclear medicine procedures, and (iii) naturally occurring radionuclides in drinking water or resulting from existing or past NORM industrial activities. (paper)

Airborne particulate concentrations and fluxes at an active uranium mill tailings site

International Nuclear Information System (INIS)

Sehmel, G.A.

1978-01-01

Direct measurements of airborne particulate concentrations and fluxes of transported mill tailing materials were measured at an active mill tailings site. Experimental measurement equipment consisted of meteorological instrumentation to automatically activate total particulate air samplers as a function of wind speed increments and direction, as well as particle cascade impactors to measure airborne respirable concentrations as a function of particle size. In addition, an inertial impaction device measured nonrespirable fluxes of airborne particles. Caclulated results are presented in terms of the airborne solid concentration in g/m 3 , the horizontal airborne mass flux in g/(m 2 -day) for total collected nonrespirable particles and the radionuclide concentrations in dpm/g as a function of particle diameter for respirable and nonrespirable particles

Activity concentrations of 137Cs and 40K in mosses from spas in Eastern Serbia

Directory of Open Access Journals (Sweden)

Čučulović Ana

2012-01-01

Full Text Available With the aim of detecting the presence of radionuclides in moss samples in eastern Serbia, 129 samples of mosses were collected from 2000 to 2010 in the region of the spas: Sokobanja, Banja Jošanica and Gamzigradska banja. The data obtained show that 137Cs was present in all of the 129 samples from 3 sampling areas and 15 sampling localities and in 20 moss taxa. This indicates that pollution with this radionuclide resulting from the Chernobyl accident still exists. Changes in the average activity concentrations of 40K are within measurement error limits, while for 137Cs changes in the average activity concentrations are more noticeable, i.e. they have decreased with time. [Acknowledgments. This work was supported by the Ministry of Education and Science of the Republic of Serbia, project code III 43009.

Natural Radionuclides and 137Cs Concentrations in Rice in Jepara Residence and Internal Dose Estimation Intake by the People

International Nuclear Information System (INIS)

Leli-Nirwani; Minarni; Buchari

2001-01-01

The measurement of natural radionuclides and 137 Cs concentration in rice in Jepara residence and internal dose estimation intake by people have been conducted. The aim of the research is to determine internal dose estimation of natural radionuclides and 137 Cs intake by people in Jepara residence. By knowing the natural radionuclides and 137 Cs concentrations in rice at Jepara residence, the dose coefficient for adult from ICRP No.72 and the annual intake consumption take from the Indonesian food balance published by BPS, the internal dose from natural radionuclides and 137 Cs intake from food can be calculate concentration of 228 Th, 226 Ra and 137 Cs were found in Bayuran, with the average value was (2.00±0.21) x 10 -5 Bq/kg, (0.09±0.25) x 10 -5 Bq/kg, (19.00±0.06) x 10 -5 Bq/kg respectively the highest 40 K concentration was found in Pandansili with the average was about (8.40 ± 0.34) x 10 -5 Bq/kg. The estimation of equivalent doses from intake of 228 Th, 226 Ra, 40 K, and 137 Cs in rice were the highest in Bayuran the value the average values, respectively, was 0.0039 x 10 -5 μ Sv/yr, 18.09 X 10 -5 μ Sv/yr, 1.63 x 10 -5 μ Sv/yr, 172.38 x 10 -5 μ Sv/yr. Result in this measurement lowest comparing by recommendation IAEA in Safety Series No. 115 in 1996. (author)

On systematic and statistic errors in radionuclide mass activity estimation procedure

International Nuclear Information System (INIS)

Smelcerovic, M.; Djuric, G.; Popovic, D.

1989-01-01

One of the most important requirements during nuclear accidents is the fast estimation of the mass activity of the radionuclides that suddenly and without control reach the environment. The paper points to systematic errors in the procedures of sampling, sample preparation and measurement itself, that in high degree contribute to total mass activity evaluation error. Statistic errors in gamma spectrometry as well as in total mass alpha and beta activity evaluation are also discussed. Beside, some of the possible sources of errors in the partial mass activity evaluation for some of the radionuclides are presented. The contribution of the errors in the total mass activity evaluation error is estimated and procedures that could possibly reduce it are discussed (author)

An assessment of natural radionuclides in water of Langat River estuary, Selangor

Energy Technology Data Exchange (ETDEWEB)

Hamzah, Zaini, E-mail: tengkuliana88@gmail.com; Rosli, Tengku Nurliana Tuan Mohd, E-mail: tengkuliana88@gmail.com; Saat, Ahmad, E-mail: tengkuliana88@gmail.com; Wood, Ab. Khalik, E-mail: tengkuliana88@gmail.com [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

2014-02-12

An estuary is an area that has a free connection with the open sea and it is a dynamic semi-enclosed coastal bodies. Ex-mining, aquaculture and industrial areas in Selangor are the sources of pollutants discharged into the estuary water. Radionuclides are considered as pollutants to the estuary water. Gamma radiations emitted by natural radionuclides through their decaying process may give impact to human. The radiological effect of natural radionuclides which are {sup 226}Ra, {sup 228}Ra, {sup 40}K, {sup 238}U and {sup 232}Th, were explored by determining the respective activity concentrations in filtered water along the Langat estuary, Selangor. Meanwhile, in- situ water quality parameters such as temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using YSI portable multi probes meter. The activity concentration of {sup 226}Ra, {sup 228}Ra and {sup 40}K were determined by using gamma-ray spectrometry with high-purity germanium (HPGe) detector. The activity concentrations of {sup 226}Ra, {sup 228}Ra and {sup 40}K in samples are in the range of 0.17 - 0.67 Bq/L, 0.16 - 0.97 Bq/L and 1.22 - 5.57 Bq/L respectively. On the other hand, the concentrations of uranium-238 and thorium-232 were determined by using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The thorium concentrations are between 0.17 ppm to 0.28 ppm and uranium concentrations were 0.25 ppm to 0.31 ppm. The results show activity concentrations of radionuclides are slightly high near the river estuary. The Radium Equivalent, Absorbed Dose Rate, External Hazard Index, and Annual Effective Dose of {sup 226}Ra, {sup 228}Ra and {sup 40}K are also studied.

Natural radionuclides in food in an area with high concentrations of radionuclides; Radionuclídeos naturais em alimentos em uma área com altas concentrações de radionuclídeos

Energy Technology Data Exchange (ETDEWEB)

Pereira, W.S.; Moraes, S.R.; Cavalcante, J.J.V. [Universidade Veiga de Almeida (UVA), Rio de Janeiro, RJ (Brazil); Kelecom, A. [Universidade Federal Fluminense (UFF), Niterói, RJ (Brazil); Silva, A.X. da; Lopez, J.M.; Filgueiras, R.; Carmo, A.S., E-mail: pereiras@gmail.com, E-mail: lararapls@hotmail.com, E-mail: Ademir@nuclear.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

2017-07-01

Areas of high natural radiation expose the local population to doses greater than the world average. One of the routes of exposure is food intake. The activity concentration (AC) of 5 natural radionuclides in 7 types of foods was analyzed. The highest CA measured was 2.40 Bq.kg{sup -1} for the U{sub nat} in the potato. The multivariate statistic identified two groups: (U{sub nat}e {sup 232}Th) and [({sup 210}Pb and {sup 228}Ra) and {sup 226}Ra].

Influence of microbial activity on the migration behaviour of redox-sensitive radionuclides (technetium and selenium) in loose rock

International Nuclear Information System (INIS)

Stroetmann, I.

1995-01-01

In closed cycle column tests under sterile conditions there was no or hardly any sorption of the two radionuclides. In closed cycle column tests with unsterile soils, however, the two radionuclides were extremely immobilised (80 % of the output activity of Tc-95m and 40 % of the output activity of Se-75). By inoculation of the sterile columns with mixed soil cultures an increase in sorption of 40 % of the output activity was achieved which is attributed to the microbial activity. The adsorbed radionuclides in unsterile columns could be remobilized by adding a bactericide. In columns with saline water the sorption of radionuclides was slightly lower. Soils with a 5 % organic carbon content showed extremely increased sorption of the two radionuclides. In comparison with closed cycle columns shake tests were carried out. During turbulent intermixing of water and solid, no sorption of technetium was observed in unsterile tests either, while Se-75 added as selenite was strongly adsorbed to the solid. When adding acetate as a C-source, the microbially conditioned reduction of the redox potential to -100 mV and, subsequently, a strong increase of sorption could be observed. A reduction of the pH value in the soils to pH 4, and simultaneous adding of acetate significally reduced the microbial activity and the sorption of technetium, while selenite sorption remained strong as before. Sorption tests with bacteria-pure and mixed cultures showed no sorption of the pertechnetate anion in the oxidation stage (VII). However, when reducing the pertechnetate by means of SnCl2, up to 40 % of the feed activity of killed and living biomass was immobilized. Between 20-30 % of the adsorbed technetium quantity was outside at the membrane, and 40% inside the cells. After a three-day incubation period in a technetium-containing solution, a factor of 15,5 was achieved as the maximum intracellular concentration factor for the isolate 143 (Xanthomas sp.). (orig./MG) [de

Bilateral Comparison CIEMAT-CENTIS-DMR for radionuclide activity measurements

International Nuclear Information System (INIS)

Oropesa Verdecia, P.; Garcia-Torano, E.

2004-01-01

We present the results of a bilateral comparison of radionuclide activity measurements between the Radionuclide Metrology Department of the Center of Isotopes of Cuba (CENTIS-DMR), and the Ionising Radiation Metrology Laboratory (LMRI) of the Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT) of Spain. The aim of the comparison was to establish the comparability of the measurement instruments and methods used to obtain radioactive reference materials of some gamma-emitting nuclides at CENTIS-DMR. The results revealed that there are no statistically significant differences between the data reported by both laboratories. (Author) 7 refs

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Allen, S.E.; Horrill, A.D.; Howard, B.J.; Lowe, V.P.W.; Parkinson, J.A.

1983-07-01

The subject is discussed under the headings: concentration and spatial distribution of radionuclides in grazed and ungrazed saltmarshes; incorporation of radionuclides by sheep grazing on an estuarine saltmarsh; inland transfer of radionuclides by birds feeding in the estuaries and saltmarshes at Ravenglass; radionuclides in contrasting types of coastal pastures and taken up by individual plant species found in west Cumbria; procedures developed and used for the measurement of alpha and gamma emitters in environmental materials. (U.K.)

Accumulation of radionuclides in selected marine biota from Manjung coastal area

Energy Technology Data Exchange (ETDEWEB)

Abdullah, Anisa, E-mail: coppering@ymail.com; Hamzah, Zaini; Wood, Ab. Khalik [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450, Shah Alam, Selangor (Malaysia); Saat, Ahmad [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450, Shah Alam, Selangor (Malaysia); Institute of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Alias, Masitah [TNB Reasearch Sdn. Bhd., Kawasan Institusi Penyelidikan, 43000 Kajang, Selangor (Malaysia)

2015-04-29

Distribution of radionuclides from anthropogenic activities has been intensively studied due to the accumulation of radionuclides in marine ecosystem. Manjung area is affected by rapid population growth and socio-economic development such as heavy industrial activities including coal fired power plant, iron foundries, port development and factories, agricultural runoff, waste and toxic discharge from factories.It has radiological risk and toxic effect when effluent from the industries in the area containing radioactive materials either being transported to the atmosphere and deposited back over the land or by run off to the river and flow into coastal area and being absorbed by marine biota. Radionuclides presence in the marine ecosystem can be adversely affect human health when it enters the food chain. This study is focusing on the radionuclides [thorium (Th), uranium (U), radium-226 ({sup 226}Ra), radium-228 ({sup 228}Ra) and potassium-40 ({sup 40}K)] content in marine biota and sea water from Manjung coastal area. Five species of marine biota including Johnius dussumieri (Ikan Gelama), Pseudorhombus malayanus (Ikan Sebelah), Arius maculatus (Ikan Duri), Portunus pelagicus (Ketam Renjong) and Charybdis natator (Ketam Salib) were collected during rainy and dry seasons. Measurements were carried out using Inductively Coupled Plasma Mass Spectrometer (ICPMS). The results show that the concentration of radionuclides varies depends on ecological environment of respective marine biota species. The concentrations and activity concentrations are used for the assessment of potential internal hazard index (H{sub in}), transfer factor (TF), ingestion dose rate (D) and health risk index (HRI) to monitor radiological risk for human consumption.

Accumulation of radionuclides in selected marine biota from Manjung coastal area

International Nuclear Information System (INIS)

Abdullah, Anisa; Hamzah, Zaini; Wood, Ab. Khalik; Saat, Ahmad; Alias, Masitah

2015-01-01

Distribution of radionuclides from anthropogenic activities has been intensively studied due to the accumulation of radionuclides in marine ecosystem. Manjung area is affected by rapid population growth and socio-economic development such as heavy industrial activities including coal fired power plant, iron foundries, port development and factories, agricultural runoff, waste and toxic discharge from factories.It has radiological risk and toxic effect when effluent from the industries in the area containing radioactive materials either being transported to the atmosphere and deposited back over the land or by run off to the river and flow into coastal area and being absorbed by marine biota. Radionuclides presence in the marine ecosystem can be adversely affect human health when it enters the food chain. This study is focusing on the radionuclides [thorium (Th), uranium (U), radium-226 ( 226 Ra), radium-228 ( 228 Ra) and potassium-40 ( 40 K)] content in marine biota and sea water from Manjung coastal area. Five species of marine biota including Johnius dussumieri (Ikan Gelama), Pseudorhombus malayanus (Ikan Sebelah), Arius maculatus (Ikan Duri), Portunus pelagicus (Ketam Renjong) and Charybdis natator (Ketam Salib) were collected during rainy and dry seasons. Measurements were carried out using Inductively Coupled Plasma Mass Spectrometer (ICPMS). The results show that the concentration of radionuclides varies depends on ecological environment of respective marine biota species. The concentrations and activity concentrations are used for the assessment of potential internal hazard index (H in ), transfer factor (TF), ingestion dose rate (D) and health risk index (HRI) to monitor radiological risk for human consumption

Accumulation of radionuclides in selected marine biota from Manjung coastal area

Science.gov (United States)

Abdullah, Anisa; Hamzah, Zaini; Saat, Ahmad; Wood, Ab. Khalik; Alias, Masitah

2015-04-01

Distribution of radionuclides from anthropogenic activities has been intensively studied due to the accumulation of radionuclides in marine ecosystem. Manjung area is affected by rapid population growth and socio-economic development such as heavy industrial activities including coal fired power plant, iron foundries, port development and factories, agricultural runoff, waste and toxic discharge from factories.It has radiological risk and toxic effect when effluent from the industries in the area containing radioactive materials either being transported to the atmosphere and deposited back over the land or by run off to the river and flow into coastal area and being absorbed by marine biota. Radionuclides presence in the marine ecosystem can be adversely affect human health when it enters the food chain. This study is focusing on the radionuclides [thorium (Th), uranium (U), radium-226 (226Ra), radium-228 (228Ra) and potassium-40 (40K)] content in marine biota and sea water from Manjung coastal area. Five species of marine biota including Johnius dussumieri (Ikan Gelama), Pseudorhombus malayanus (Ikan Sebelah), Arius maculatus (Ikan Duri), Portunus pelagicus (Ketam Renjong) and Charybdis natator (Ketam Salib) were collected during rainy and dry seasons. Measurements were carried out using Inductively Coupled Plasma Mass Spectrometer (ICPMS). The results show that the concentration of radionuclides varies depends on ecological environment of respective marine biota species. The concentrations and activity concentrations are used for the assessment of potential internal hazard index (Hin), transfer factor (TF), ingestion dose rate (D) and health risk index (HRI) to monitor radiological risk for human consumption.

Concentration and speciation of radionuclides in environmental samples

International Nuclear Information System (INIS)

Testa, C.; Desideri, D.; Meli, M.A.; Roselli, C.

2000-01-01

The paper will describe three examples dealing with the measure of some natural (U, Th, 2 10Pb, 4 0K) and artificial ( 1 37Cs, 9 0Sr, 2 39 +2 40Pu, 2 41Am) radionuclides in environmental samples such as mosses, sediments, soils. Extraction chromatography, liquid extraction, selective precipitation and electroplating were used to isolate the radionuclides, except for gamma emitters which were detected by gamma spectrometry. Alpha spectrometry were used to measure the alpha emitters and low background beta detector to measure the beta emitters

Baseline concentrations of radionuclides and heavy metals in soils and vegetation around the DARHT facility: Construction phase (1996)

International Nuclear Information System (INIS)

Fresquez, P.R.; Haagenstad, H.T.; Naranjo, L. Jr.

1997-04-01

As part of the Department of Energy's Mitigation Action Plan for the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility at Los Alamos National Laboratory (LANL), baseline concentrations of radionuclides ( 3 H, 137 Cs, 90 Sr, 238 Pu, 239 Pu, 241 Am, total U), and heavy metals (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se and Tl) in soil, sediment, and vegetation (overstory and understory) around the DARHT facility during the construction phase in 1996 were determined. Also, U and Be concentrations in soil samples collected in 1993 from within the proposed DARHT facility area are reported. Most radionuclides in soils, sediments, and vegetation were within current background and/or long-term regional statistical reference levels

Relationship of soil terrestrial radionuclide concentrations and the excess of lifetime cancer risk in western Mazandaran Province, Iran.

Science.gov (United States)

Abbaspour, M; Moattar, F; Okhovatian, A; Kharrat Sadeghi, M

2010-12-01

The main goal of this study is to lay out the map of the soil radionuclide activity concentrations and the terrestrial outdoor gamma dose rates in the western Mazandaran Province of Iran, and to present an evaluation scheme. Mazandaran Province was selected due to its special geographical characteristics, high population density and the long terrestrial and aquatic borders with the neighbouring countries possessing nuclear facilities. A total of 54 topsoil samples were collected, ranging from the Nour to Ramsar regions, and were based on geological conditions, vegetation coverage and the sampling standards outlined by the International Atomic Energy Agency. The excess lifetime cancer risks (ELCRs) were evaluated and the coordinates of sampling locations were determined by the global positioning system. The average terrestrial outdoor gamma dose rate was 612.38 ± 3707.93 nGy h(-1), at 1 m above the ground. The annual effective gamma dose at the western part of Mazandaran Province was 750 μSv, and the ELCR was 0.26 × 10(-2). Soil samples were analysed by gamma spectrometry with a high-purity germanium detector. The average (226)Ra, (232)Th, (40)K and (137)Cs activities were 1188.50 ± 7838.40, 64.92 ± 162.26, 545.10 ± 139.42 and 10.41 ± 7.86 Bq kg(-1), respectively. The average soil radionuclide concentrations at the western part of Mazandaran Province were higher than the worldwide range. The excess lifetime risks of cancer and the annual effective gamma doses were also higher than the global average.

Concentrations and activity ratios of uranium isotopes in groundwater from Donana National Park, South of Spain

International Nuclear Information System (INIS)

Bolivar, J. P.; Olias, M.; Gonzalez-Garcia, F.; Garcia-Tenorio, R.

2008-01-01

The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Donana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and 210 Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that 234 U/ 238 U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer

Public Health Goal for Naturally Occurring Radionuclides in Groundwater

International Nuclear Information System (INIS)

Kamel, N.H.M.; Omar, H.A.; El-Baset, L.A.

2008-01-01

Naturally occurring and man-made radionuclide in groundwater may have a health hazardous to some residents. The objective of this work is to provide criteria for safety of drinking-water with respect to the chemical parameters and the radionuclide content. The annual effective dose for the consumption of drinking water was considered. Ground water samples were selected from different sites in Egypt, that have the most population, it were taken from aquifer regions along Giza sites in Egypt. Chemical analyses for the major anions, cations, and the radiological analyses were tested . Activity concentrations (Bq/l) of the gross alpha and the gross beta activities of our investigated samples were compared with the maximum contaminant level (MCL) of the world health organization (WHO). Some of the water samples were found to have a higher of gross beta and alpha particles than the MCL. Alpha activity were found depending on to the total dissolved solids (TDS) content of the water samples. Gamma activity concentrations were analyzed using low background germanium detector, the higher of activity values was found in some investigated samples is due to increasing of 226 Ra and 228 Ra activities. Tritium activity concentrations also were measured using soft beta liquid scintillation counter, it was found lower than the MCL. Our investigated samples were found to have a higher concentrations of the phosphate, nitrites, iron, and manganese contents than the maximum permissible limit, all the ground water samples were found to have a higher of silica and alumina content. Commercial carbon powder and natural clay materials were tested as ion exchangers for the removal of inorganic contaminants in the ground water samples. Clay materials was found to have a higher selectivity than activated carbon for the removal of radionuclides, phosphates, nitrites, and manganese content at the ground water samples

Anthropogenic radionuclide fluxes and distribution in bottom sediments of the cooling basin of the Ignalina Nuclear Power Plant

International Nuclear Information System (INIS)

Marčiulionienė, D.; Mažeika, J.; Lukšienė, B.; Jefanova, O.; Mikalauskienė, R.; Paškauskas, R.

2015-01-01

Based on γ-ray emitting artificial radionuclide spectrometric measurements, an assessment of areal and vertical distribution of 137 Cs, 60 Co and 54 Mn activity concentrations in bottom sediments of Lake Drūkšiai was performed. Samples of bottom sediments from seven monitoring stations within the cooling basin were collected in 1988–1996 and 2007–2010 (in July–August). For radionuclide areal distribution analysis, samples from the surface 0–5 cm layer were used. Multi sample cores sliced 2 cm, 3 cm or 5 cm thick were used to study the vertical distribution of radionuclides. The lowest 137 Cs activity concentrations were obtained for two stations that were situated close to channels with radionuclide discharges, but with sediments that had a significantly smaller fraction of organic matter related to finest particles and consequently smaller radionuclide retention potential. The 137 Cs activity concentration was distributed quite evenly in the bottom sediments from other investigated monitoring stations. The highest 137 Cs activity concentrations in the bottom sediments of Lake Drūkšiai were measured in the period of 1988–1989; in 1990, the 137 Cs activity concentrations slightly decreased and they varied insignificantly over the investigation period. The obtained 238 Pu/ 239,240 Pu activity ratio values in the bottom sediments of Lake Drūkšiai represented radioactive pollution with plutonium from nuclear weapon tests. Higher 60 Co and 54 Mn activity concentrations were observed in the monitoring stations that were close to the impact zones of the technical water outlet channel and industrial rain drainage system channel. 60 Co and 54 Mn activity concentrations in the bottom sediments of Lake Drūkšiai significantly decreased when operations at both INPP reactor units were stopped. The vertical distribution of radionuclides in bottom sediments revealed complicated sedimentation features, which may have been affected by a number of natural and

Seasonal variations in activity concentrations of 99Tc and 137Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea.

Science.gov (United States)

Copplestone, D; Jackson, D; Hartnoll, R G; Johnson, M S; McDonald, P; Wood, N

2004-01-01

Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of (99)Tc, as a result of the treatment of previously stored waste, with consequent increases in (99)Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of (99)Tc and (137)Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of (99)Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of (99)Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg(-1) (fresh weight (fw)) in crabs and 124 to 216 Bq kg(-1) (fw) in lobsters, with no observed seasonal variations. Activity concentrations of (137)Cs in both crab and lobster were lower, ranging from lobster meat (fw). A statistically significant increase in activity concentrations of (137)Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves during the active

Cultivation experiments on uptake of radionuclides by mushrooms

International Nuclear Information System (INIS)

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

1994-01-01

After the Chernobyl accident, high concentrations of radiocesium in mushrooms were found in Europe. In our previous studies, we found that 137 Cs concentrations in mushrooms were markedly higher than autotrophic plants. In order to study radionuclide uptake by mushrooms, cultivation experiments in flasks were carried out using radiotracers, 137 Cs, 85 Sr, 60 Co, 54 Mn and 65 Zn. Three mushroom species Hebeloma vinosophyllum, Flammulina velutipes and Coprinus phlyctidosporus were used. In addition, a plant sample, Medicago sativa, was also tested. We found mushrooms tended to accumulate Cs, although there was a large difference between mushroom species. The concentration ratio, which was defined as 'activity of radionuclide in mushroom (Bq/g, wet wt.)' divided by 'activity of radionuclide in medium (Bq/g, wet wt.)', had the highest value of 21 for Cs in H. vinosophyllum. The value was much higher than that in the plant sample. The present findings agreed with previous observations in which Hebeloma species collected in forests contained large amount of 137 Cs. Considerable accumulations were not found for Sr and Co. The concentration ratio of Mn for the mushrooms was about 10, while the ratio of Zn ranged from 15 to 30. The effects of stable elements in the medium on the accumulations were investigated and was found the concentration ratios of Cs, Sr and Co were not influenced highly by coexisting stable elements in the medium. But the concentration ratio of Mn decreased as the amount of coexisting stable elements in the medium was increased. (author)

Radionuclides in plankton from the South Pacific Basin

International Nuclear Information System (INIS)

Marsh, K.V.; Buddemeier, R.W.

1984-01-01

An investigation has been initiated of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10 4 . In 1956 and 1958 considerable work was done on the accumulation and distribution of a variety of fission and activation products produced by nuclear tests in the Marshall Islands. Since then, studies, have largely been confined to a few radionuclides, and most of the work in the last twenty years has been done in the northern hemisphere. The authors participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. The authors were able to measure concentrations in plankton of the naturally-occurring radionuclides 7 Be, 40 K, and the U and Th series, and they believe that they have detected low levels of 144 Ce and 95 Nb in seven samples ranging as far south as 68 0 . Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures, 1 table

A mobile sampler for mesuring the concentration of radionuclides and their physico chemical forms in natural waters

International Nuclear Information System (INIS)

Spezzano, P.; Giacomelli, R.; Bortoluzzi, S.; Montealto, M.; Nocente, M.

1990-01-01

This paper describes the realization of a sampler for concentrating radionuclides from large volume of natural waters with the purpose to determine their concentration levels and their physico-chemical forms. Sample is pumped at a flow rate of about 0.5 m 3 /h through a set of sequential filters with different pore sizes to achieve separation of 'particulate' from 'dissolved' forms. Filtered samples is then passed through sequential beds of cation and anion exchange resins and activated alumina to obtain separation of dissolved forms on the basis of their charge. Ammonium Hexacianocobalt Ferrate (NCFC is used as a selective exchanger for Cesium isotopes. Filter and exchangers are measured by computerized gamma spectrometry. Detection limits are of a few tenths of Bq per cubic meter of sample. The main results obtained during radioecological surveys are also presented

Radionuclide mass inventory, activity, decay heat, and dose rate parametric data for TRIGA spent nuclear fuels

International Nuclear Information System (INIS)

Sterbentz, J.W.

1997-03-01

Parametric burnup calculations are performed to estimate radionuclide isotopic mass and activity concentrations for four different Training, Research, and Isotope General Atomics (TRIGA) nuclear reactor fuel element types: (1) Aluminum-clad standard, (2) Stainless Steel-clad standard, (3) High-enrichment Fuel Life Improvement Program (FLIP), and (4) Low-enrichment Fuel Life Improvement Program (FLIP-LEU-1). Parametric activity data are tabulated for 145 important radionuclides that can be used to generate gamma-ray emission source terms or provide mass quantity estimates as a function of decay time. Fuel element decay heats and dose rates are also presented parametrically as a function of burnup and decay time. Dose rates are given at the fuel element midplane for contact, 3.0-feet, and 3.0-meter detector locations in air. The data herein are estimates based on specially derived Beginning-of-Life (BOL) neutron cross sections using geometrically-explicit TRIGA reactor core models. The calculated parametric data should represent good estimates relative to actual values, although no experimental data were available for direct comparison and validation. However, because the cross sections were not updated as a function of burnup, the actinide concentrations may deviate from the actual values at the higher burnups

Is the human nasal cavity at risk from inhaled radionuclides?

International Nuclear Information System (INIS)

Boecker, B.B.; Hahn, F.F.; Cuddihy, R.G.; Snipes, M.B.; McClellan, R.O.

1986-01-01

In a series of three life-span studies in which beagle dogs inhaled relatively soluble forms of beta-emitting radionuclides, a number of cancers of the nasal cavity have arisen at long times after the inhalation exposure. No such cancers were observed in the control dogs. Data obtained in other studies involving serial sacrifice of dogs that received these radionuclides in similar forms have shown that high local concentrations of the radionuclides can persist in nasal turbinates for long periods of time, depending on the physical half-life of the radionuclide inhaled. Several nasal carcinomas have also been observed in dogs injected with 137 CsCl in which the relative concentrations of beta activity in the turbinate region were not as pronounced as in the above studies. Similar risks of sinonasal cancer were calculated for dogs in each of these studies regardless of differences in radionuclide, dosimetry, and route of administration. Since sinonasal cancers have occurred in people exposed to alpha-emitting radionuclides, it is reasonable to assume this could occur with beta emitters as well. Radiation protection guidelines should account for the sinonasal region being at risk. 23 refs., 1 fig., 6 tabs

Infusion of radionuclides throughout pregnancy

International Nuclear Information System (INIS)

Mountford-Lister, P.G.; Lambert, B.E.; Milner, A.C.; Kang, X.Z.

1992-01-01

This work is part of a long-term study to examine the cancer incidence in the offspring of mice exposed to 239 Pu or 147 Pm throughout pregnancy. The need to model the human intake scenario and the possibility of a critical period during uterine development necessitates constant availability of radionuclides throughout pregnancy. Various methods (multiple daily injections, infusion by external cannula and infusion by indwelling osmotic pump) have been examined and osmotic infusion pumps chosen. These pumps result in a near-constant blood concentration for up to 21 days. Part of the study is the estimation of dose to the critical haemopoietic tissues of the pup from a knowledge of the radionuclide distribution and kinetics. At present the distribution has been followed from birth to 180 days. Activity in the suckling pups at 7 days old is around 1 percent of the infused activity, though most of this is accounted for by the contents of the stomach and gastrointestinal tract. The liver and femur account for around 0.025 percent and 0.012 percent respectively per pup. Activity increases in both liver and femur during lactation after which both concentration and activity fall with time. Long-term studies with the pups of dams exposed to a range of 239 Pu concentrations between 0-70 kBq/kg are underway. Correlation of average organ dose with tumour incidence will be determined at completion of the life-span study. (Author) 39 refs., 5 tabs., 6 figs

Removal of radionuclides from liquid streams by reverse osmosis

International Nuclear Information System (INIS)

Deshmukh, U.A.; Ramachandhran, V.; Misra, B.M.

1987-01-01

Separation of radionuclides in trace concentrations by cellulose acetate membranes has been under investigation in this laboratory, and the behaviour of some important radionuclides such as 137 Cs and 90 Sr under reverse osmosis has been reported earlier. The present work deals with a few other typical radionuclides such as 60 Co, 103 Ru and 131 I which are not fully amenable to conventional methods for their removal. Separation of these radionuclides from liquid streams by the reverse osmosis process was studied using a small reverse osmosis test cell. Various parameters like membrane porosity, applied pressure and feed activity levels were investigated. Cellulose acetate membranes offer reasonable separation of 60 Co, 103 Ru and 131 I radionuclides, indicating the potential of reverse osmosis for treatment of effluents containing these radioisotopes. The percent separation is found to be in the order of Co > Ru > I. The percent radioactive separation improves with increases in feed activity. The performance data are explained in terms of solution-diffusion mechanism. It appears that the separation of radionuclides is not governed by diffusion alone, but by the interaction of solutes with the membranes. (author)

Natural-series radionuclides in traditional North Australian aboriginal foods

Energy Technology Data Exchange (ETDEWEB)

Murray, A.S.; Johnston, A.; Hancock, G.J.; Martin, P. [Environmental Research Institute of the Supervising Scientist (ERISS), Jabiru (Australia)

1997-07-01

Activity concentrations of the radionuclides {sup 226}Ra, {sup 210}Pb, {sup 210}Po, {sup 238}U, {sup 234}U, {sup 230}Th, {sup 232}Th and {sup 227}Ac were measured in edible flesh of traditional Aboriginal food items from the Magela and Cooper Creek systems in the tropical Northern Territory of Australia. Fish, buffalo, pig, magpie goose, filesnake, goanna, turtle, freshwater shrimp and freshwater crocodile were studied. Activity concentrations in water were also measured to enable the calculation of concentration ratios (CRs).For most edible flesh samples, activity concentrations followed the approximate order: {sup 210}Po>>{sup 226210}[{sup 234}Usimilar{sup 238}[{sup 230}Thsimilar{sup 232}Th]. The {sup 210}Po/{sup 210}Pb activity ratio was particularly high (greater than 100) for pig flesh. CRs for fish species fall into two groups. Group 1 (bony bream and sleepy cod) had CRs about five times higher than for group 2 (eight other species). CRs for turtle flesh were similar to those for fish in group 1, while those for turtle liver were about a factor of 10 higher. CRs for magpie goose, filesnake, freshwater shrimp, goanna and crocodile flesh were also of the same order as for fish in groups 1 or 2.Calculations of dose resulting from release of wastewaters from uranium mining operations in the region show that the dominant pathway would be uptake of radionuclides, especially {sup 226}Ra, by freshwater mussels, followed by radionuclide uptake by fish. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

The enrichment of natural radionuclides in oil shale-fired power plants in Estonia – The impact of new circulating fluidized bed technology

International Nuclear Information System (INIS)

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-01-01

Burning oil shale to produce electricity has a dominant position in Estonia's energy sector. Around 90% of the overall electric energy production originates from the Narva Power Plants. The technology in use has been significantly renovated – two older types of pulverized fuel burning (PF) energy production units were replaced with new circulating fluidized bed (CFB) technology. Additional filter systems have been added to PF boilers to reduce emissions. Oil shale contains various amounts of natural radionuclides. These radionuclides concentrate and become enriched in different boiler ash fractions. More volatile isotopes will be partially emitted to the atmosphere via flue gases and fly ash. To our knowledge, there has been no previous study for CFB boiler systems on natural radionuclide enrichment and their atmospheric emissions. Ash samples were collected from Eesti Power Plant's CFB boiler. These samples were processed and analyzed with gamma spectrometry. Activity concentrations (Bq/kg) and enrichment factors were calculated for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides and for 40 K in different CFB boiler ash fractions. Results from the CFB boiler ash sample analysis showed an increase in the activity concentrations and enrichment factors (up to 4.5) from the furnace toward the electrostatic precipitator block. The volatile radionuclide ( 210 Pb and 40 K) activity concentrations in CFB boilers were evenly distributed in finer ash fractions. Activity balance calculations showed discrepancies between input (via oil shale) and output (via ash fractions) activities for some radionuclides ( 238 U, 226 Ra, 210 Pb). This refers to a situation where the missing part of the activity (around 20% for these radionuclides) is emitted to the atmosphere. Also different behavior patterns were detected for the two Ra isotopes, 226 Ra and 228 Ra. A part of 226 Ra input activity, unlike 228 Ra, was undetectable in the solid

The performance test of NAA laboratory at radionuclide measure with low activity

International Nuclear Information System (INIS)

Sri Murniasih; Sukirno

2016-01-01

The performance test to measure the I-131 radionuclide activity has been carried out at CAST-NAA laboratory. The purpose of this activity is to know the performance of a laboratory in the testing of low radioactivity sample. The tested sample consists of the form I-131 radionuclide sources shaped thin plastic disk with a certain weight. Evaluation of laboratory performance test results carried out by the organizer of the program test appeal (PTKMR-BATAN). Evaluation results showed that testing of point source of the I-131 radionuclide with comparative method gives a good enough results with errors below 10%. The results of the performance test evaluation are useful as the external quality control to a testing method that is expected in NAA laboratory. (author)

Radionuclide examinations

International Nuclear Information System (INIS)

Lentle, B.C.

1989-01-01

This paper reports on radionuclide examinations of the pancreas. The pancreas, situated retroperitonally high in the epigastrium, was a particularly difficult organ to image noninvasively before ultrasonography and computed tomography (CT) became available. Indeed the organ still remains difficult to examine in some patients, a fact reflected in the variety of methods available to evaluate pancreatic morphology. It is something of a paradox that the pancreas is metabolically active and physiologically important but that its examination by radionuclide methods has virtually ceased to have any role in day-to-day clinical practice. To some extent this is caused by the tendency of the pancreas's commonest gross diseases emdash carcinoma and pancreatitis, for example emdash to result in nonfunction of the entire organ. Disorders of pancreatic endocrine function have generally not required imaging methods for diagnosis, although an understanding of diabetes mellitus and its nosology has been advanced by radioimmunoassay of plasma insulin concentrations

Radionuclides in soil and vegetables in the Novi Sad area

International Nuclear Information System (INIS)

Krmar, M.; Slivka, J.; Djurcic, Z.; Zikic, N.; Bikit, I.; Conkic, Lj.

1999-01-01

The results of radiological control of soil from the fields for vegetable breeding in Novi Sad region are presented in this paper. Using obtained values of concentration activity and known transfer-factors contents of some radionuclides in several vegetables was estimated. The values of activity concentration obtained by direct measurements are lower than estimated ones. (author)

Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

Energy Technology Data Exchange (ETDEWEB)

McMurtry, G.M.; Schneider, R.C. (Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics); Colin, P.L. (Hawaii Inst. of Marine Biology, Honolulu (USA)); Buddemeier, R.W. (California Univ., Livermore (USA). Lawrence Livermore Lab.); Suchanek, T.H. (Fairleigh Dickinson Univ., St. Croix, Virgin Islands (USA). West Indies Lab.)

1985-02-21

The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

International Nuclear Information System (INIS)

McMurtry, G.M.; Schneider, R.C.; Buddemeier, R.W.; Suchanek, T.H.

1985-01-01

The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon. (author)

A Bayesian approach to assess data from radionuclide activity analyses in environmental samples

International Nuclear Information System (INIS)

Barrera, Manuel; Lourdes Romero, M.; Nunez-Lagos, Rafael; Bernardo, Jose M.

2007-01-01

A Bayesian statistical approach is introduced to assess experimental data from the analyses of radionuclide activity concentration in environmental samples (low activities). A theoretical model has been developed that allows the use of known prior information about the value of the measurand (activity), together with the experimental value determined through the measurement. The model has been applied to data of the Inter-laboratory Proficiency Test organised periodically among Spanish environmental radioactivity laboratories that are producing the radiochemical results for the Spanish radioactive monitoring network. A global improvement of laboratories performance is produced when this prior information is taken into account. The prior information used in this methodology is an interval within which the activity is known to be contained, but it could be extended to any other experimental quantity with a different type of prior information available

Concentrations of radionuclides and selected stable elements in fruits and vegetables

International Nuclear Information System (INIS)

Oakes, T.W.; Shank, K.E.

1977-01-01

Twenty-two types of fruits and vegetables collected from two commercial supermarkets have been analyzed for their radionuclidic and stable-element composition. A specific gamma-emitting isotope analysis was performed on each sample for 40 K, 60 Co, 95 Zr-Nb, 106 Ru, 137 Cs, 226 Ra, and 232 Th. The concentration of the stable elements in each sample were determined using multi-element neutron-activation analysis (Al, Ag, Au, As, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Hf, I, K, La, Mn, Mo, Mg, Na, Rb, Sb, Sc, Se, Sr, Ta, Te, Th, Ti, Zn, Zr) and atomic absorption (Cd, Ni, Pb). Information on the composition of a typical diet is used to estimate the radiological dose to man subsequent to ingestion of these fruits and vegetables. The stable-elemental compositions of the foodstuffs analyzed were compared with estimated values assuming foliar deposition and long-term buildup of effluents from a large modern coal-fired steam plant. It is tentatively concluded that for the general case of a precipitator-equipped, coal-fired steam plant, no toxic levels of trace elements in foodstuffs are expected as a result of the plant operation

Radionuclide concentrations in soils and produce from Cochiti, Jemez, Taos, and San Ildefonso Pueblo Gardens

International Nuclear Information System (INIS)

Fresquez, P.R.; Armstrong, D.R.; Salazar, J.G.

1995-05-01

Radionuclide ( 3 H, 90 Sr, 137 Cs, 238 Pu, 239 Pu, and total uranium) concentrations were determined in soils and produce collected from Cochiti, Jemez, Taos, and San Ildefonso Pueblo gardens. All radionuclides in soils from Pueblo areas were within or just above regional statistical (natural and/or worldwide fallout) reference levels. Similarily, the average levels of radionuclides in produce collected from Cochiti, Jemez, Taos, and San Ildefonso Pueblo gardens were not significantly different in produce collected from regional (background) locations. The effective (radiation) dose equivalent from consuming 352 lb of produce from Cochiti, Jemez, Taos, and San Ildefonso, after natural background has been subtracted, was 0.036 (±0.016), 0.072 (±0.051), 0.012 (±0.027), and 0.110 (±0.102) mrem/yr, respectively. The highest calculated dose, based on the mean + 2 std dev (95% confidence level), was 0.314 mrem/yr; this was <0.4% of the International Commission on Radiological Protection permissible dose limit for protecting members of the public

Content of Natural Radionuclides in Sediments in the Vicinity of a Former Uranium Mine

International Nuclear Information System (INIS)

Strok, M.; Planinsek, P.; Smodis, B.

2011-01-01

Former Slovenian uranium mine Zirovski vrh lies in the subalpine environment with relative high rainfall and population density. As a legacy of uranium mining, Jazbec and Borst waste piles were constructed in the vicinity of a former uranium mine. On the Jazbec waste pile, about 2.5 millions of tons of spoil, and 0.05 millions of tons of red mud were deposited. Average activity concentrations in spoil are 750 Bq/kg for 238U, 226Ra and 230Th, and in red mud 495 Bq/kg for 238U, 190 Bq/kg for 226Ra and 65100 Bq/kg for 230Th. On the Borst waste pile, about 0.6 millions of tons of uranium mill tailings (UMT) were deposited. Average activity concentrations in UMT are 995 Bq/kg for 238U, 8630 Bq/kg for 226Ra and 3930 Bq/kg for 230Th. Seepage waters with elevated radionuclide concentrations from both waste piles flow in the nearby streams Brebovscica and Todrascica. Todrascica outfalls into the Brebovscica and Brebovscica into the Poljanska Sora River. Due to the different biogeochemical processes, natural radionuclides from both waste piles can be transferred to the sediments of the affected streams. These processes are mainly driven by the sorption onto the particles and particles settling or by the direct diffusion to sediments. Therefore the aim of this work was to find out at which extent these processes occur in the specific case by comparing activity concentrations in sediments before and after inflow of seepage waters from both waste piles. In sediment samples, 238U, 234U, 230Th, 226Ra, 210Pb and 210Po activity concentrations were determined, using radiochemical separations followed by either alpha spectrometry or proportional counting. Results of the content of natural radionuclides in sediments in the vicinity of a former uranium mine showed that activity concentrations of all analyzed radionuclides were higher in sediments after the inflow of seepage waters from waste piles in Brebovscica and Todrascica stream. This was not the case for Poljanska Sora River

Radionuclide toxicity

International Nuclear Information System (INIS)

Galle, P.

1982-01-01

The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

Arrival of radionuclides released by the Fukushima accident to Tenerife (Canary Islands)

International Nuclear Information System (INIS)

López-Pérez, M.; Ramos-López, R.; Perestelo, Nayra R.; Duarte-Rodriguez, X.; Bustos, J.J.; Alonso-Pérez, S.; Cuevas, E.; Hernández-Armas, J.

2013-01-01

Two weeks after the accident at the Fukushima-Daichi nuclear power plant, 131I, 137Cs and 134Cs activities were measured in two different stations located in Tenerife (Canary Islands), situated at 300 (FIMERALL) and 2400 (IZAÑA) m.a.s.l, respectively. Peak measured activity concentrations were: 1.851 mBq/m3 (131I); 0.408 mBq/m3 (137Cs) and 0.382 mBq/m3 (134Cs). The activities measured at the FIMERALL station were always higher than at IZAÑA station, suggesting that the radioactive plume arrived to the island associated with low altitude air masses. Simulations of potential dispersion of the radioactive cloud (137Cs) after the nuclear accident in reactor Fukushima I show that radioactive pollution reached remote regions such as the Canary Islands in the Eastern subtropical North Atlantic. The corresponding effective dose to the local population was 1.17 nSv, a value less than one millionth of the annual limit for the general public. Therefore, there was no risk to public health. - Highlights: ► Arrival of radionuclides to Tenerife following the accident of Fukushima. ► The atmospheric concentration of radionuclides was always higher at low altitude. ► After reaching the peak concentration a sharp decrease of radionuclides was observed. ► Air mass forward trajectory analysis confirms the potential arrival of radionuclides to Tenerife.

Radionuclides in marine mammals off the Portuguese coast

International Nuclear Information System (INIS)

Malta, Margarida; Carvalho, Fernando P.

2011-01-01

Radionuclide analyses were performed in tissue samples including muscle, gonad, liver, mammary gland, and bone of marine mammals stranded on the Portuguese west coast during January-July 2006. Tissues were collected from seven dolphins (Delphinus delphis and Stenella coeruleoalba) and one pilot whale (Globicephala sp.). Samples were analyzed for 210 Po and 210 Pb by alpha spectrometry and for 137 Cs and 40 K by gamma spectrometry. Po-210 concentrations in common dolphin's muscle (D. delphis) averaged 56 ± 32 Bq kg -1 wet weight (w.w.), while 210 Pb averaged 0.17 ± 0.07 Bq kg -1 w.w., 137 Cs averaged 0.29 ± 0.28 Bq kg -1 w.w., and 40 K 129 ± 48 Bq kg -1 w.w. Absorbed radiation doses due to these radionuclides for the internal organs of common dolphins were computed and attained a 1.50 μGy h -1 on a whole body basis. 210 Po was the main contributor to the weighted absorbed dose, accounting for 97% of the dose from internally accumulated radionuclides. These computed radiation doses in dolphins are compared to radiation doses from 210 Po and other radionuclides reported for human tissues. Due to the high 210 Po activity concentration in dolphins, the internal radiation dose in these marine mammals is about three orders of magnitude higher than in man. - Highlights: → In marine mammals the highest activity concentrations were those of 40 K and 210 Po. → Absorbed radiation doses in dolphin tissues attained 1.50 mGy h -1 on a whole body basis. → Po-210 was the main contributor (97%) to the internal absorbed radiation dose. → The high 210 Po concentration in the marine mammal's tissues is due to food chain transfer. → The absorbed radiation dose in dolphins is three orders of magnitude higher than in man.

Radionuclide transport from near-surface repository for radioactive waste - The unsaturated zone approach

Energy Technology Data Exchange (ETDEWEB)

Jakimaviciute-Maseliene, V. [Vilnius University (Lithuania); Mazeika, J. [Nature Research Centre (Lithuania); Motiejunas, S. [Radioactive Waste Management Agency (Lithuania)

2014-07-01

About 100 000 m{sup 3} of solid conditioned Low and Intermediate Level Waste (LILW), generated during operation and decommissioning of the Ignalina nuclear power plant (INPP), are to be disposed of in a near-surface repository (NSR) - a 'hill'-type repository with reinforced concrete vaults and with engineered and natural barriers. The northeastern Lithuania and the environment of the INPP in particular were recognized as the areas most suitable for a near-surface repository (Stabatiske Site). The engineered barriers of the repository consist of concrete cells surrounded by clay-based material of low permeability with about the same isolating capacity in all directions. The clay materials must be effectively compactable so that required hydraulic conductivity is reached. The Lithuanian Triassic clay turned out to be sufficiently rich in smectites and was proposed as main candidate for sealing of the repository. When the concrete vaults are filled, the repository cover will be constructed. The surface of the mound will be planted with grass. In this study a computer code FEFLOW 5.0 was applied for simulating the transport of the most mobile radionuclides ({sup 3}H, {sup 14}C, {sup 59}Ni and {sup 94}Nb) with moisture through an unsaturated vault of the near-surface repository in Stabatiske Site. The HYDRUS-1D analysis was used to assess the radionuclide transport in the repository and to estimate initial activity concentrations of radionuclides transported from the cemented waste matrix. Radionuclide release from the vault in the unsaturated conditions after closure of the repository and consequent contaminant plume transport has been assessed taking into account site-specific natural and engineering conditions and based on a normal evolution scenario. The highest peak radionuclide activity concentrations were estimated applying the FEFLOW code. The highest value of {sup 14}C activity concentration(about 1.3x10{sup 8} Bq/m{sup 3}) at the groundwater table

Neutron activation of microspheres containing 165Ho: theoretical and experimental radionuclidic impurities study

International Nuclear Information System (INIS)

Squair, Peterson L.; Pozzo, Lorena; Ivanov, Evandro; Osso Junior, Joao A.

2011-01-01

The 166 Ho microspheres are potentially interesting for medical applications for treatment of many tumors. The internal radionuclide therapy can use polymer or glass device that provides structural support for the radionuclide. After activation, beta minus emission of 166 Ho (T 1/2 =26.8h, β - E max =1.84 MeV, γ E p =80.6 keV) can be used for therapeutic purposes. The aim of this work is study the influence of radionuclide impurities between End of Bombardment (EOB) and the medical application. The appropriate specific activities and purity along decay should be adequate for their safe and efficient medical applications. The good practices on neutron activation techniques are choice a high purity target to avoid production of undesirable radionuclides and when possible with enriched targets to obtain higher specific activity. In this work the target used was Ho 2 O 3 and polymeric microspheres containing holmium acetylacetonate (HoAcAc) manufactured at the Biotechnology Center-IPEN/CNEN-SP. Three conditions were evaluated: preliminary test with 1.0x10 13 n.cm -2 s -1 for 1.0 hour; nowadays maximum capability of IEA-R1 reactor with 5.0x10 13 n.cm -2 s -1 for 64.0 hours and the ideal IEA-R1 operation with 5.0x10 13 n.cm -2 s -1 for 120.0 hours. Considering the sample with 99.9% 165 Ho purity and 0.1% for each impurities elements with its natural abundance, the highest radionuclidic impurity is the Lutetium followed by Ytterbium, Lanthanum and Cerium. The intrinsic radionuclidic impurity of 166 mHo is less relevant. This review is important to identify the radionuclidic purity characteristics of the preliminary studies with different time and flux irradiation. The data produced in this paper will help to define strategies for the production of 166 Ho radioisotope at IEA-R1 IPEN/CNEN-SP reactor. (author)

Levels and effects of natural radionuclides in soil samples of Garhwal Himalaya

International Nuclear Information System (INIS)

Manjulata Yadav; Mukesh Rawat; Anoop Dangwal; Mukesh Prasad; Gusain, G.S.; Ramola, R.C.

2014-01-01

Distribution of natural radionuclide gives significant parameter to assess the presence of gamma radioactivity and its radiological effect in our environment. Natural radionuclides are present in the form of 226 Ra, 232 Th and 40 K in soil, rocks, water, air, and building materials. Distribution of natural radionuclides depends on the type of minerals present in the soil and rocks. For this purpose gamma spectrometer is used as tool for finding the concentration of these radionuclides. The activity concentration of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in these soil samples were found to vary from of 8 ± 1 Bq/kg to 50 ± 10 Bq/kg with an average 20 Bq/kg, 7 ± 1-88 ± 16 Bq/kg with an Average 26 Bq/kg and 115 ± 18-885 ± 132 Bq/kg with an average 329 Bq/kg, respectively. In this paper, we are presenting the radiological effect due to distribution of natural radionuclide present in soil of Garhwal Himalaya. (author)

Distribution of radionuclides and elements in Cubatao River sediments

International Nuclear Information System (INIS)

Silva, P.S.C.; Mazzilli, B.P.; Favaro, D.I.T.

2006-01-01

Cubatao River is located in Santos Basin, Sao Paulo State, Brazil. This region is characterized by the occurrence of estuaries and mangrove. Due to its location, near the coastal line, it is also an important industrial area, where phosphate fertilizer plants, petrol refineries, and chemical and steel industries are present. Such human activities contribute to the enhancement of elemental composition in sediments and, in some cases, also increase the radionuclide concentrations, the so called Technologically Enhanced Natural Occurring Radioactive Materials (TENORM). The contamination of land and sediments by TENORM is of major concern. The activity concentration of U and Th series radionuclides was determined in five sediment samples from Cubatao River. The activity concentration ratio was also determined. Equilibrium was observed for the ratio 234 U/ 238 U. The activity ratios of Th/ 238 U, 228 Ra/ 226 Ra and 210 Pb/ 226 Ra were higher than the unity. In the first two cases, the observed values are due to the higher activity of Th in the sediment and in the last case are probably due to the atmospheric deposition of 210 Pb. (author)

Activities concentration of 239+240Pu in sediment in Sabah and Sarawak coastal area

International Nuclear Information System (INIS)

Jalal Sharib; Zaharudin Ahmad; Yii Mei Wo; Ahmad Sanadi Abu Bakar; Norfaizal Mohamed; Kamarozaman Ishak; Zulkifli Daud

2008-08-01

The determination of plutonium, 239+240 Pu activity concentration and their distributions along the coastal area of the Sabah and Sarawak have been performed using alpha spectrometry counting system. The sampling coastal sediment for this study was carried out in July 2004 as part of the Marine Radioactivity Database Development Project for Malaysia. This results show that the distribution of Plutonium, 239+240 Pu radionuclides in coastal sediment is consistent, their activities are depending on the sampling locations. Generally, the 239+240 Pu activities measured in Sabah and Sarawak coastal sediment are in the range of BDL - 1.83 Bq/kg and 0.11 - 0.841 Bq/kg dry weights, respectively. The sampling stations, Persisiran Lubok Sabanan, SB 15 and Sungai Similajau, SR 13 showed the highest plutonium, 239+240 Pu radionuclides isotopes activity in Sabah and Sarawak. Meanwhile, these two stations shows higher activity compare to West Coast of Peninsular of Malaysia station for the Marine Radioactivity Database Development Project for Malaysia. (Author)

Radionuclide transfer onto ground surface in surface water flow, 1

International Nuclear Information System (INIS)

Mukai, Masayuki; Takebe, Shinichi; Komiya, Tomokazu; Kamiyama, Hideo

1991-07-01

Radionuclides migration in ground surface water flow is considered to be one of the important path way in the scenario for environmental migration of radionuclides leaked from low level radioactive waste repository. Simulating the slightly sloped surface on which contaminated solution is flowing downward, testing for radionuclide migration on ground surface had been started. As it's first step, an experiment was carried out under the condition of restricted infiltration in order to elucidate the adsorption behavior of radionuclides onto the loamy soil surface in related with hydraulic conditions. Radionuclides concentration change in effluent solution with time and a concentration distribution of radionuclides adsorbed on the ground surface were obtained from several experimental conditions combining the rate and the duration time of the water flow. The radionuclides concentration in the effluent solution was nearly constant during each experimental period, and was reduced under the condition of lower flow rate. The surface distribution of radionuclides concentration showed two distinctive regions. The one was near the inlet vessel where the concentration was promptly reducing, and the other was following the former where the concentration was nearly constant. The characteristic surface distribution of radionuclides concentration can be explained by a two dimensional diffusion model with a first order adsorption reaction, based on the advection of flow rate distribution in perpendicular direction. (author)

Radionuclides in marine organisms

International Nuclear Information System (INIS)

Honda, Teruyuki

2001-01-01

The concentration and accumulation of radionuclides in marine organisms were explained in this paper. Secular change of the radioactivity concentration of 137 Cs in seaweed in coastal area of Japan showed more than 5Bq/kg-fresh in the first half of 1960, but decreased less than 1 Bq/kg-fresh after then and attained to less than 0.1 Bq/kg-fresh in 1990s. However, the value increased a while in 1986, which indicated the effect of Chernobyl accident. The accident increased 137 Cs of shellfish near Japan. The concentration of 239+240 Pu was the lowest value in muscles of fish, but increased from 1.7 to 42.3 mBq/kg wet wt in seaweed in 1999. 99 Tc concentration of seaweed showed from 100 to 1000 times as much as that of seawater. Radionuclides in the Irish Sea are originated from Sellafield reprocessing plant. The concentration factors of macro-algae and surface water fish (IAEA,1985) were shown. Analytical results of U in 61 kinds of marine organs showed that the concentration was different in the part of organ. The higher concentration of U was observed in hard tissue of fish. The concentration factor was different between chemical substances with the same radionuclides. (S.Y.)

Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

International Nuclear Information System (INIS)

Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A.; Brunk, J.A.

1986-07-01

This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, 137 Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of 137 Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. 90 Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of 60 Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of 60 Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of 207 Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of 207 Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, 207 Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of 207 Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither 239+240 Pu nor 241 Am is significantly accumulated in the muscle tissue of any species of fish. Apparently, 238 Pu is in a more readily available form for accumulation by fishes than 239+240 Pu. Based on a daily ingestion rate of 200 q of fish flesh, dose rates to individuals through the fish-food ingestion pathway are well below current Federal guidelines

High resolution simultaneous measurements of airborne radionuclides

International Nuclear Information System (INIS)

Abe, T.; Yamaguchi, Y.; Tanaka, K.; Komura, K.

2006-01-01

High resolution (2-3 hrs) simultaneous measurements of airborne radionuclides, 212 Pb, 210 Pb and 7 Be, have been performed by using extremely low background Ge detectors at Ogoya Underground Laboratory. We have measured above radionuclides at three monitoring points viz, 1) Low Level Radioactivity Laboratory (LLRL) Kanazawa University, 2) Shishiku Plateau (640 m MSL) located about 8 km from LLRL to investigate vertical difference of activity levels, and 3) Hegura Island (10 m MSL) located about 50 km from Noto Peninsula in the Sea of Japan to evaluate the influences of Asian continent or mainland of Japan on the variation to the activity levels. Variations of short-lived 212 Pb concentration showed noticeable time lags between at LLRL and at Shishiku Plateau. These time lags might be caused by change of height of a planetary boundary layer. On the contrary, variations of long-lived 210 Pb and 7 Be showed simultaneity at three locations because of homogeneity of these concentrations all over the area. (author)

The effects of different uranium concentrations on soil microbial populations and enzymatic activities

International Nuclear Information System (INIS)

Bagherifam, S.; Lakziyan, A.; Ahmadi, S. J.; Fotovvat, A.; Rahimi, M. F.

2010-01-01

Uranium is an ubiquitous constituent of natural environment with an average concentration of 4 mg/kg in earth crust. However, in local areas it may exceed the normal concentration due to human activities resulting in radionuclide contamination in groundwater and surface soil. The effect of six levels of uranium concentration (0, 50, 100,250. 500 and 1000 mg kg -1 ) on soil phosphatase activities and microbial populations were studied in a completely randomized design as a factorial experiment with three replications. The results showed a significant decrease in phosphatase activity. The result of the experiment suggests that soil microbial populations (bacteria, funji and actinomycetes) decrease by increasing the uranium levels in the soil. Therefore, assessment of soil enzymatic activities and microbial populations can be helpful as a useful index for a better management of uranium and radioactive contaminated soils.

Radionuclide concentrations in fish collected from Jemez, Nambe, and San Ildefonso Tribal Lakes

International Nuclear Information System (INIS)

Fresquez, P.R.; Armstrong, D.R.; Salazar, J.G.

1995-02-01

Radionuclide concentrations ( 90 Sr, 137 Cs, 238 Pu, 239 Pu,and total uranium) were determined in fish collected from Jemez, Nambe, and San Ildefonso tribal lakes. With the exception of 137 Cs, all other radionuclides were not significantly different in (stocked) rainbow trout collected from Jemez and Nambe as compared with game fish collected from Abiquiu, Heron, and El Vado Reservoirs. Although 137 Cs levels in trout from Jemez (3.2 x 10 -2 pCi per dry gram) and Nambe (7.5 x 10 -2 pCi per dry gram) were significantly higher than 137 Cs concentrations in fish from Abiquiu, Heron, and El Vado, they were still well below the regional statistical (worldwide fallout) reference level (i.e., -2 pCi per dry gram). Game and nongame fish collected from San Ildefonso contained higher and significantly higher concentrations of uranium, respectively, as compared with fish collected from Abiquiu, Heron, and El Vado. The higher uranium concentrations in fish from San Ildefonso as compared with fish from Abiquiu, Heron, and El Vado were attributed to the higher natural soil uranium contents in the area as compared with the geology of the area upstream of San Ildefonso. The effective (radiation) dose equivalent (EDE) from consuming 46 lb of game fish from Jemez, Nambe, and San Ildefonso lakes, after natural background has been subtracted, was 0.013 (±0.002), 0.019 (±0.012), and 0.017 (±0.028) mrem/yr, respectively. Similarly, the EDE from consuming nongame fish from San Ildefonso was 0.0092 (±0.0084) mrem/yr. The highest calculated dose, based on the mean + 2 standard deviation (95% confidence level), was 0.073 mrem/yr; this was <0.08% of the International Commission on Radiological Protection permissible dose limit for protecting members of the public

Evaluation of the radionuclide concentrations in soil and plants from the 1975 terrestrial survey of Bikini and Eneu Islands

International Nuclear Information System (INIS)

Colsher, C.S.; Robison, W.L.; Gudiksen, P.H.

1977-01-01

In June 1975 a radiological survey was conducted of the terrestrial environment of Bikini and Eneu islands (Bikini Atoll) to evaluate the potential radiation dose to the returning Bikini population. In this report, we present measurements of the radionuclide concentration in soil profiles and in dominant species of edible and nonedible, indicator plants. The use of these data to derive relationships to predict the plant uptake of radionuclides from soil is described. Approximately 620 soil and vegetation samples from Bikini and Eneu Islands were analyzed by Ge(Li) gamma spectrometry and by wet chemistry. The predominant radionuclides in these samples were 60 Co, 90 Sr, 137 Cs, /sup 239,240/Pu, 241 Pu, and 241 Am

Radionuclide inventories for the F- and H-area seepage basin groundwater plumes

Energy Technology Data Exchange (ETDEWEB)

Hiergesell, Robert A [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kubilius, Walter P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-05-01

Within the General Separations Areas (GSA) at the Savannah River Site (SRS), significant inventories of radionuclides exist within two major groundwater contamination plumes that are emanating from the F- and H-Area seepage basins. These radionuclides are moving slowly with groundwater migration, albeit more slowly due to interaction with the soil and aquifer matrix material. The purpose of this investigation is to quantify the activity of radionuclides associated with the pore water component of the groundwater plumes. The scope of this effort included evaluation of all groundwater sample analyses obtained from the wells that have been established by the Environmental Compliance & Area Completion Projects (EC&ACP) Department at SRS to monitor groundwater contamination emanating from the F- and H-Area Seepage Basins. Using this data, generalized groundwater plume maps for the radionuclides that occur in elevated concentrations (Am-241, Cm-243/244, Cs-137, I-129, Ni-63, Ra-226/228, Sr-90, Tc-99, U-233/234, U-235 and U-238) were generated and utilized to calculate both the volume of contaminated groundwater and the representative concentration of each radionuclide associated with different plume concentration zones.

Evaluation of natural radionuclides in selected regions of Slovak Republic

International Nuclear Information System (INIS)

Porubcanova, B.; Mojzes, A.; Nikodemova, D.

2014-01-01

Slovakian part of Western Carpathian is an area typical for very various geological structures. This fact is also reflected on values of natural radionuclide concentrations. Our paper was focused on evaluation and collection of data about activities of different natural radionuclides (uranium, thorium and potassium) and on the description of rocks which cause it. For research purposes were offered the results obtained from middle and eastern Slovakia which includes different types of rocks with various values of radioactive concentrations. Consequently these data were processed and shown by maps that represent the values of natural radioactivity in the studied areas. (authors)

Evaluation of natural radionuclides in selected regions of Slovak Republic

International Nuclear Information System (INIS)

Porubcanova, B.; Nikodemova, D.; Mojzes, A.

2014-01-01

Slovakian part of Western Carpathian is an area typical for very various geological structures. This fact is also reflected on values of natural radionuclide concentrations. Our poster was focused on evaluation and collection of data about activities of different natural radionuclides (uranium, thorium and potassium) and on the description of rocks which cause it. For research purposes were offered the results obtained from middle and eastern Slovakia which includes different types of rocks with various values of radioactive concentrations. Consequently these data were processed and shown by maps that represent the values of natural radioactivity in the studied areas. (authors)

Solubility limited radionuclide transport through geologic media

International Nuclear Information System (INIS)

Muraoka, Susumu; Iwamoto, Fumio; Pigford, T.H.

1980-11-01

Prior analyses for the migration of radionuclides neglect solubility limits of resolved radionuclide in geologic media. But actually some of the actinides may appear in chemical forms of very low solubility. In the present report we have proposed the migration model with no decay parents in which concentration of radionuclide is limited in concentration of solubility in ground water. In addition, the analytical solutions of the space-time-dependent concentration are presented in the case of step release, band release and exponential release. (author)

Natural radionuclides in Brazilian underground mines

International Nuclear Information System (INIS)

Santos, Talita de Oliveira

2015-01-01

Rock, soil and water contain "2"3"8U and "2"3"2Th and their decay products. The distribution of these radionuclides differs in terms of activity concentration depending on the mineral type and origin. All ore processing releases long and short half-life radionuclides, mainly radon and its progeny. It is important to monitor this gas and its decay products in underground mines in order to assess the radiological hazards of the exposed workers. On this concern, the present work outlines the characterization of brazilian underground mines with relation to natural radionuclides, specially radon and its progeny. The radon concentration was measured by using E-PERM Electrets Ion Chamber (Radelec), AlphaGUARD (Saphymo GmbH) and CR-39 (Landauer) track etch detectors. The radon progeny was determined by using DOSEman detector. The equilibrium state between radon and its progeny was calculated. Based on these data, the total effective dose for miners was estimated. Moreover, the contribution from the main sources to the radon level inside mines was evaluated. For this, the following detectors were used: measurements of radon concentrations in soil gas were carried out by using AlphaGUARD detector; "2"2"6Ra ("2"1"4Bi), "2"3"2Th e "4"0K specific activity in ore and soil samples were determined by using gamma-ray spectrometry HPGe detector (Canberra); and radon concentration in groundwater samples was performed by using RAD7 (Durridge Inc.). The radon concentration ranged from 113 to 8171 Bq.m"-"3 and the Equilibrium Equivalent Concentration varied from 76 to 1174 Bq.m"-"3. The equilibrium factor mean value was 0.4 (0.2 -0.7). The workers estimated total effective dose ranged from 1 to 22 mSv.a"-"1 (mean 10 mSv.a"-"1). Therefore, results show the importance to assess continually and permanently the radon and its progeny behavior and the need to adopt safety measurements against natural radiation in underground mines environment. (author)

An application of clonal Japanese flounder, paralichthys olivaceus to the experiment on bioaccumulation of radionuclides

International Nuclear Information System (INIS)

Miyazaki, Taeko; Nakahara, Motokazu; Nakamura, Ryoichi; Hirano, Shigeki; Watabe, Teruhisa; Yamamoto, Eiichi

2000-01-01

A laboratory experiment of accumulation and excretion of radionuclides ( 125 I, 57 Co, 141 Ce, 103 Ru, 85 Sr, 137 Cs, 54 Mn) in juvenile Japanese flounder was carried out in order to elucidate the genetic factor intervening in the mineral balance, which possibly caused the fluctuation of so-called concentration factors. Fish originating from two populations, namely clone brood and hatchery-reared brood, were used in the present study. The variance of concentration of radionuclides was compared in terms of the radionuclides activity ratio, which was defined by radionuclide concentration in fish normalized by that in surrounding water. In general, narrower variations of concentration were observed in clone brood than in hatchery-reared brood, and significant differences were observed for 57 Co, 141 Ce and 137 Cs in the accumulation process and for five radionuclides other than 125 I and 103 Ru in excretion process. The present study suggested that a probability of application of clonal fish would be advantageous in experimental assessments of biological effects of environmental contaminants in the sea. (author)

Experimental studies on correlation between accumulation of radionuclides by fish, availability of bottom sediments, and concentration of microelements in water

Energy Technology Data Exchange (ETDEWEB)

Katkov, A E

1979-07-01

There are revealed peculiarities of accumulation of radionuclides desorbed from the ground by hydrobionts as compared with the accumulation of radionuclides appearing in the basin for the first time. The results of the experimental investigations on the dependence of nuclide accumulation coefficients (AC) on their concentration in water are summarized. The experiments have been performed on adult (6-8 years) golden crucian carp Carassius carassius in a basin with fresh water with /sup 51/Cr, /sup 54/Mn, /sup 59/Fe, /sup 60/Co, /sup 90/Sr, /sup 95/Zr, /sup 106/Ru, /sup 125/Sb, /sup 131/I, /sup 137/Cs, /sup 144/Ce, /sup 210/Po. The radionuclide group (/sup 54/Mn, /sup 144/Ce, /sup 210/Po) has been found out. The ground has contributed to its accumulation. For another group (/sup 60/Co, /sup 137/Cs, /sup 51/Cr) it has been found an indistinctly expressed influence only of silt containing ground on AC. The third group comprises the radionuclides (/sup 90/Sr, /sup 95/Zr, /sup 106/Ru, /sup 125/Sb, /sup 131/I) accumulation of which in fish has been prevented by the ground. An inverse correlation between the nuclide AC changes in fishes (..delta..K) and changes in the concentration of their isotope carried (..delta..C) in water has been observed. The results of the mathematical processing of the summarized experimental data according to the ..delta..Kx ..delta..C=1 criterion are described by the dependence close to ACxC..-->.. const., cor. responding to the law of tendency to constancy preservation in the microelement concentration tissues. In the course of investigation of the relationship between the AC and the change of the radionuclide aggregate state in water no common dependence has been established.

Relationships between sea-bed radionuclide activities and some sedimentological variables

International Nuclear Information System (INIS)

Ligero, R.A.; Ramos-Lerate, I.; Barrera, M.; Casas-Ruiz, M.

2001-01-01

Natural radionuclides ( 232 Th, 226 Ra, 40 K) and 137 Cs, coming from atmospheric radioactive fallout, have been measured in sea-bed sediments of the Bay of Cadiz (South Western Spain). In this report, multivariate analysis methods have been employed to study the relationships between the activities of the radionuclides and some sedimentological variables like granulometric facies, organic content and apparent density. The correlation functions found show that it is possible to determine, with a satisfactory degree of approximation, the granulometric facies of the sediments using only radiometric information

Literature review of the concentration ratios of selected radionuclides in freshwater and marine fish

Energy Technology Data Exchange (ETDEWEB)

Poston, T.M.; Klopfer, D.C.

1986-09-01

Concentration ratios (CR's) used for modeling the uptake and food chain transport of radionuclides in fish have usually been conservative; that is, at the high end of reported values. This practice ensures that the dose to the consumer of contaminated fish will not be underestimated. In many models, however, conservative values have been used for all variables that have any uncertainty associated with them. As a result the dose to the consumer is overestimated. Realistic CR values need to be developed to establish model parameters that will accurately reflect tissue burdens in fish and resulting dose rates to consumers. This report reviews and summarizes published literature on the uptake and distribution of stable and radioactive isotopes of 26 elements. Based on this review, we have made recommendations on CR values to be used for modeling the accumulation of radionuclides in fish. Our recommendations are compared with CR values reported in other publications. A generic discussion of abiotic and biotic factors that influence CR values is provided so that CR values may be adjusted based on site-specific characteristics of the fishes habitat. Recommended CR values for freshwater fish and for marine fish are listed. Although this report emphasizes radionuclides, it is applicable to stable elements as well.

Literature review of the concentration ratios of selected radionuclides in freshwater and marine fish

International Nuclear Information System (INIS)

Poston, T.M.; Klopfer, D.C.

1986-09-01

Concentration ratios (CR's) used for modeling the uptake and food chain transport of radionuclides in fish have usually been conservative; that is, at the high end of reported values. This practice ensures that the dose to the consumer of contaminated fish will not be underestimated. In many models, however, conservative values have been used for all variables that have any uncertainty associated with them. As a result the dose to the consumer is overestimated. Realistic CR values need to be developed to establish model parameters that will accurately reflect tissue burdens in fish and resulting dose rates to consumers. This report reviews and summarizes published literature on the uptake and distribution of stable and radioactive isotopes of 26 elements. Based on this review, we have made recommendations on CR values to be used for modeling the accumulation of radionuclides in fish. Our recommendations are compared with CR values reported in other publications. A generic discussion of abiotic and biotic factors that influence CR values is provided so that CR values may be adjusted based on site-specific characteristics of the fishes habitat. Recommended CR values for freshwater fish and for marine fish are listed. Although this report emphasizes radionuclides, it is applicable to stable elements as well

Thin-target excitation functions: a powerful tool for optimizing yield, radionuclidic purity and specific activity of cyclotron produced radionuclides

International Nuclear Information System (INIS)

Bonardi, M.L.

2002-01-01

In accelerator production of radionuclides, thin-target yield, y(E), is defined as a function of the projectile energy E, at the End Of an Instantaneous Bombardment (EOIB), as the slope at the origin of the growing curve of the activity per unit beam current (A/I) of a specific radionuclide vs. irradiation time, for a target in which the energy loss is negligible with respect to the projectile energy itself. In practice, y(E) is defined as the second derivative of A/I with respect to particle energy and irradiation time, calculated when the irradiation time tends to zero (EOIB). The thin-target yields of different radionuclides, produced by direct and side reactions, are numerically fitted, taking into account the overall statistical errors as weights. The 'effective' cross-section σ ± (E) as a function of projectile energy is proportional to thin-target yield, but the physical meaning of this parameter is poor, being only a raw summation of the several cross sections of the reaction channels concerned, weighted on target isotopic composition. Conversely, Thick-Target Yield, Y(E,ΔE), is defined as a two parameter function of the incident particle energy E(MeV) onto the target and the energy loss ΔE (MeV), in the target itself, obtained by integration of thin-target excitation function, y(E). This approach holds in the strict approximation of a monochromatic beam of energy E, not affected by either intrinsic energy spread or straggling. The energy straggling is computed by Monte Carlo computer codes, like TRIM 2001. In case of total particle energy absorption in the target, for a nuclear reaction of energy threshold E th , the function Y(E,ΔE) reaches a value Y(E,E- E th ), for ΔE=E- E th , that represents mathematically the envelope of the Y(E,ΔE) family of curves. This envelope is a monotonically increasing curve, never reaching either a maximum or a saturation value, even if its slope becomes negligible for high particle energies and energy losses. Some

Seasonal variations in activity concentrations of 99Tc and 137Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea

International Nuclear Information System (INIS)

Copplestone, D.; Jackson, D.; Hartnoll, R.G.; Johnson, M.S.; McDonald, P.; Wood, N.

2004-01-01

Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of 99 Tc, as a result of the treatment of previously stored waste, with consequent increases in 99 Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of 99 Tc and 137 Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of 99 Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of 99 Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg -1 (fresh weight (fw)) in crabs and 124 to 216 Bq kg -1 (fw) in lobsters, with no observed seasonal variations. Activity concentrations of 137 Cs in both crab and lobster were lower, ranging from -1 for crab meat (fw) and -1 for lobster meat (fw). A statistically significant increase in activity concentrations of 137 Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves

Radionuclide concentration in drinking water from public supplies in the metropolitan area of Recife, Brazil

International Nuclear Information System (INIS)

Melo, N.P.; Amaral, R.S.; Silva, C.M.; Hazin, C.A.; Lima, R.A.; Valentim, E.

2000-01-01

There has been an increasing concern with the assessment of human exposure to naturally occurring radionuclides as they account for around 70% of the total dose received by the population. Most of the exposure derived from natural terrestrial sources comes from the radionuclides in the uranium series, which is headed by the long-lived isotope 238 U. Radionuclides pertaining to this decay chain, such as, 226 Ra, 222 Ra, 210 Pb and 210 Po are the most important to be studied, as far as the dose to the population is concerned. In order to verify if the levels of radioactive contaminants in the water from public supplies are in compliance with the limits set by the Ministry of Health, a survey has been carried out in the metropolitan area of Recife, Brazil. This paper reports the results of this survey for both, superficial and groundwater supplies. Water samples collected from 107 sampling points were analyzed to determine their content of natural uranium, 226 Ra, 222 Ra, 210 Pb and 210 Po. Uranium concentrations were determined by fluorimetry after extraction with an organic solvent and deposition in LiF/NaF pellets, which were fused at 1000degC. Radium-226 was determined by the emanation technique, whereas 222 Rn was determined by liquid scintillation counting. Polonium-210, on the other hand, was determined by alpha spectrometry, following its spontaneous plating in copper disks immersed in the water samples. Measured concentrations ranged from 43 to 1330 mBq/L for natural uranium, 5.3 to 83.7 Bq/L for 222 Rn and from below the MDL (22 mBq/L) to 337 mBq/L for 210 Po. The annual intake of each radionuclide was calculated by considering an ingestion of 2L of water per day. The dose to each organ considered important to the ingestion pathway was calculated by using the masses given in the ICRP 23 for the standard man and by applying the appropriate dose conversion factors. (author)

Radionuclide content of wastewater and solid waste from a low-level effluent treatment plant

International Nuclear Information System (INIS)

Muhamat Omar; Zalina Laili; Nik Marzukee Nik Ibrahim; Mat Bakar Mahusin

2010-01-01

A study on radioactivity levels of wastewater and solid waste from a Low-level Effluent Treatment Plant has been carried out. The measurement of radionuclide concentration was carried out using gamma spectrometry. Natural and anthropogenic radionuclides were detected in solid radioactive waste recovered from the treatment plant. The presence of radionuclides in waste water varies depending on activities carried out in laboratories and facilities connected to the plant. (author)

ASSESSMENT OF RELEASE RATES FOR RADIONUCLIDES IN ACTIVATED CONCRETE.

Energy Technology Data Exchange (ETDEWEB)

SULLIVAN,T.M.

2003-08-23

The Maine Yankee (MY) nuclear power plant is undergoing the process of decontamination and decommissioning (D&D). Part of the process requires analyses that demonstrate that any radioactivity that remains after D&D will not cause exposure to radioactive contaminants to exceed acceptable limits. This requires knowledge of the distribution of radionuclides in the remaining material and their potential release mechanisms from the material to the contacting groundwater. In this study the concern involves radionuclide contamination in activated concrete in the ICI Sump below the containment building. Figures 1-3 are schematic representations of the ICI Sump. Figure 2 and 3 contain the relevant dimensions needed for the analysis. The key features of Figures 2 and 3 are the 3/8-inch carbon steel liner that isolates the activated concrete from the pit and the concrete wall, which is between 7 feet and 7 feet 2 inches thick. During operations, a small neutron flux from the reactor activated the carbon steel liner and the concrete outside the liner. Current MY plans call for filling the ICI sump with compacted sand.

Specific-activity and concentration model applied to cesium movement in an oligotrophic lake

International Nuclear Information System (INIS)

Vanderploeg, H.A.; Booth, R.S.; Clark, F.H.

1975-01-01

A linear systems-analysis model was derived to simulate the time-dependent dynamics of specific activity and concentration of radionuclides in aquatic systems. Transfer coefficients were determined for movement of 137 Cs in the components of an oligotrophic lake. These coefficients were defined in terms of basic environmental and ecological data so that the model can be applied to a wide variety of sites. Simulations with a model that ignored sediment--water interactions predicted much higher 137 Cs specific activities in the lake water and biota than did those with the complete model. Comparing 137 Cs concentrations predicted by the model with concentrations reported for the biota of an experimentally contaminated oligotrophic lake indicated that the transfer coefficients derived for the biota are adequate

Critical review: Radionuclide transport, sediment transport, and water quality mathematical modeling; and radionuclide adsorption/desorption mechanisms

Energy Technology Data Exchange (ETDEWEB)

Onishi, Y.; Serne, R.J.; Arnold, E.M.; Cowan, C.E.; Thompson, F.L. [Pacific Northwest Lab., Richland, WA (United States)

1981-01-01

This report describes the results of a detailed literature review of radionuclide transport models applicable to rivers, estuaries, coastal waters, the Great Lakes, and impoundments. Some representatives sediment transport and water quality models were also reviewed to evaluate if they can be readily adapted to radionuclide transport modeling. The review showed that most available transport models were developed for dissolved radionuclide in rivers. These models include the mechanisms of advection, dispersion, and radionuclide decay. Since the models do not include sediment and radionuclide interactions, they are best suited for simulating short-term radionuclide migration where: (1) radionuclides have small distribution coefficients; (2) sediment concentrations in receiving water bodies are very low. Only 5 of the reviewed models include full sediment and radionuclide interactions: CHMSED developed by Fields; FETRA SERATRA, and TODAM developed by Onishi et al, and a model developed by Shull and Gloyna. The 5 models are applicable to cases where: (1) the distribution coefficient is large; (2) sediment concentrations are high; or (3) long-term migration and accumulation are under consideration. The report also discusses radionuclide absorption/desorption distribution ratios and addresses adsorption/desorption mechanisms and their controlling processes for 25 elements under surface water conditions. These elements are: Am, Sb, C, Ce, Cm, Co, Cr, Cs, Eu, I, Fe, Mn, Np, P, Pu, Pm, Ra, Ru, Sr, Tc, Th, {sup 3}H, U, Zn and Zr.

Concentration and distribution of heavy metals and radionuclides in topsoils from Middle Jiu Valley surface coal exploitations sourrounding area (Gorj County, Romania)

Science.gov (United States)

Corneanu, Mihaela; Corneanu, Gabriel; Lacatusu, Anca-Rovena; Cojocaru, Luminita; Butnariu, Monica

2013-04-01

Middle Jiu Valley is one of the largest surface coal exploitation area in Romania. The coal exploitation area is a dense populated one, along the valleys are villages and the inhabitants produce for their own consumption fruits and vegetables, in their personal gardens, or cereals in the fields, nearby the villages. There was considered to be of great interest to investigate the heavy metals and radionuclides content in gardens and cropfield soils from the villages sourrounding the Thermo Electric Power Plants (TEPP) and coal surface exploitation, as well as in crude /cultivated sterile soil or ash. The topsoil samples (104) were harvested from population gardens (58), cropfields sourronding Thermo Electric Power Plants (24), crude sterile dumps (7), cultivated sterile dumps (9) and ash dumps (6). The content in radionuclides in soil was performed by Duggan (1988) method. Radionuclide activity was expressed in Bqkg-1, confidence level 95%. The total content of heavy metals in soil (Zn, Cu, Fe, Mn, Pb, Cd, Ni, Cr, Co) was measured with flame atomic mass spectrometry. The content in heavy metals was expressed in mgkg-1. Soil analysis revealed the presence of natural radionuclides, beloging from ash and coal dust, as well as of Cs-137, of Cernobal provenance. In the cropfields radionuclides content in topsoil is lower than in gardens, due to the deepper soil mobilisation. Radionuclides content over the normal limits for Romania were registered for Th-234, Pb-210, U-235 and in few locations for Ra-226. The soil content for all analysed metals was over the normal limits in most samples, in few cases with values close to allert limits. Concentrations between allert and intervention limits were registered in samples collected from 15-20 km North of TEPP Turceni, in population gardens.

Concentrations and activity ratios of uranium isotopes in groundwater from Doñana National Park, South of Spain

Science.gov (United States)

Bolívar, J. P.; Olías, M.; González-García, F.; García-Tenorio, R.

2008-08-01

The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Doñana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and 210Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that 234U/238U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer.

Natural radionuclides in soils from Sao Paulo State cerrado forest

International Nuclear Information System (INIS)

Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de

2015-01-01

Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

Natural radionuclides in soils from Sao Paulo State cerrado forest

Energy Technology Data Exchange (ETDEWEB)

Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de, E-mail: mvaleria@cnen.gov.br, E-mail: emersonemiliano@yahoo.com.br, E-mail: rebecanuclear@gmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2015-07-01

Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

Concentrations of radionuclides in imported foods from foreign countries in Japan (2000-2003)

International Nuclear Information System (INIS)

Sugiyama, Hideo; Terada, Hiroshi; Hirata, Asumi; Sakurai, Kasane; Miyata, Masahiro; Goto, Shigeo

2004-01-01

Japanese law concerning prohibition against marketing insanitary foods, etc, has defined the limit of radioactivity level in imported foods (370 Bq/kg in total of 137 Cs and 134 Cs radioactivities) post Chernobyl accident and check for this has been performed by the Ministry of Health, Labor and Welfare. The present report describes results of additional examination, conducted by National Institute of Public Health, or the Kobe or Yokohama Quarantine Station, of radionuclide (γ-emitters) concentration in imported foods during the period 2000-2003. Foods examined are from northern (40 samples) and southern (8) America, Asia (66), Oceania (9), Africa (8) and Europe (12), and are 13 kinds of grains, 12 nuts/seeds, 1 potato, 17 fruits, 12 green/yellow vegetables, 13 other vegetables, 19 mushrooms, 4 seaweeds, 15 nonessential taste items like tea leaves, 19 fishes and 12 meats. Samples are those homogenized, freeze-dried or mineralized. The Ge-semiconductor detector connected with a pulse-height analyzer is used for γ-ray detection, mainly that of 137 Cs and 134 Cs, and for 40 K as a natural radionuclide. Sample weights are 1,000-2,000 g and counting times, 100,000-300,000 seconds. Results reveal that 137 Cs alone is detectable as a artificial radionuclide but its level is as low as that in similar Japanese foods. Thus the annual effective dose due to intake of 137 Cs in imported foods is evaluated enough low in adults. (N.I.)

Methods and results of reconstruction of 131I concentration in milk from total beta-activity measurements in Belarus after Chernobyl

International Nuclear Information System (INIS)

Savkin, Mikhail; Shinkarev, Sergey; Titov, Alexey

2008-01-01

Full text: During the first few weeks following the Chernobyl accident a large scale monitoring of radioactive contamination of foodstuffs locally produced was carried out in the most contaminated areas of Belarus. Due to a lack of spectrometric instruments, radiometric devices (DP-100) were used for beta activity measurements mostly of milk and milk products. Because the intake of 131 I with milk was the main contributor of the thyroid dose for the Belarus population, it is very important to reconstruct levels of 131 I in milk for Belarus settlements. The purpose of the paper is to present the methods and results of assessing the 13I concentration in milk based on historical records of total-beta activity measurements carried out in April-June 1986 in Belarus. The results of reconstruction of the 131 I concentration in milk will be used in on-going epidemiologic studies of a cohort of Belarus children. About 20,000 total-beta activity measurements were used in the analysis; for about 50% of those, the measurement result exceeded the minimum detectable activity. Estimates of 131 I concentration in milk at the date of sampling and of time-integrated milk concentrations were reconstructed for 482 settlements in Gomel Oblast and for 100 settlements in Mogilev Oblast, the most contaminated areas in Belarus, where at least one milk measurement was available. The assessment of the 131 I concentrations in milk involved: 1) An analysis of the calibration coefficients of the detectors for radionuclides available in milk (the main radionuclides were 131 I, 132 4Cs, 137 Cs, 89 Sr, 90 Sr); and 2) An assessment of the relative activity distribution of those radionuclides in milk. Only measurements made before 21 May 1986 were considered to be reliable, as the measurements conducted late May and in June were found to be unreliable because of the decrease in 131 I concentrations and the growing influence of other radionuclides with longer half-lives. Analysis of multiple

Distribution of anthropogenic and naturally occurring radionuclides in soils and lakes of Central Spitsbergen (Arctic)

International Nuclear Information System (INIS)

Lokas, Edyta

2017-01-01

This work provides the first results on activity concentrations, inventories and activity ratios of the artificial and natural fallout ("1"3"7Cs, "2"3"8Pu, "2"3"9"+"2"4"0Pu, "2"4"1Am, "2"1"0Pb) and lithogenic radionuclides ("2"2"6Ra, "2"2"8Ra, "4"0K) in soils and lake sediments of the inland Spitsbergen. The depths of activity peaks of the artificial radionuclides point to accumulation of up to 10 cm thick deposits during last 50 years. The activity ratios of the radionuclides suggest global fallout as their source. Despite low annual precipitation the inventories of fallout radionuclides in sites not affected by the secondary deposition agree with those reported from the more humid areas of Spitsbergen. (author)

Foodstuffs, radionuclides, monitoring

International Nuclear Information System (INIS)

Denisikov, A.I.

2000-01-01

Radionuclide contamination of water and food stuffs as a result of the Chernobyl accident and permissible contents of 90 Sr and 137 Cs are considered in brief. A method of radiation monitoring of food stuffs and water for the radionuclides mentioned is suggested. The method permits employment of the simplest and cheapest radiometric equipment for analysis, whole the high degree of radionuclide concentration using fiber sorbents permits using the instrumentation without expensive shields against external radiation. A description of ion-exchange unit for radiation monitoring of liquid samples of food stuffs or water, is provided [ru

Determination of radionuclide concentrations in ground level air using the ASS-500 high volume sampler

International Nuclear Information System (INIS)

Frenzel, E.; Arnold, D.; Wershofen, H.

1996-01-01

A method for determination of radionuclide concentrations in air aerosol samples collected by the high volume aerosol sampler ASS-500 was elaborated. The aerosol sampling station ASS-500 is a Stand alone, all-weather proofed instrument. It is designed for representative sampling of airborne radionuclides from ground level air at a height of about 1.5 m above ground level. The ASS-500 station enables continuous air monitoring both normal and emergency Situations. The collection of aerosols on the Petrianov FPP-15-1.5 type filter out of an air volume of about 100,000 m 3 (sampling period 1 wk) or of about 250,000 m 3 (sampling period 3 wk) admits accurate spectrometric low level measurements of natural and artificial radionuclides. The achieved detection limit is 0.5 μBq m -3 and 0.2 μBq m -3 for 137 Cs, respectively. A new developed air flow Meter system allows to enhance the collected air volume to about 150,000 m 3 per week and lowers the detection limit to -3 for 137 Cs for weekly collected aerosol samples. In Poland the CLOR uses 9 Stations ASS-500 at different sites as atmospheric radioactivity control system. On the basis of spectrometric measurements of natural and artificial radionuclides in the collected aerosol samples at the different sites, CLOR establishes a weekly report about the radiological situation at Poland for responsible authorities. The very low achievable detection limit of the Station ASS-500 due 10 the high air flow fate and the long possible sampling period were the key argument for other government radiation protection authorities in Europe to introduce the Station ASS-500 into their low level radionuclide atmospheric monitoring programs (Austria, Belarus, France, Germany, Iceland, Spain, Switzerland, Ukraine)

Influence of microbiological activity on the mobility of redoxsensitive radionuclides in sediments

International Nuclear Information System (INIS)

Stroetmann, I.; Kaempfer, P.; Dott, W.; Schuele, J.; Sokotnejat, R.; Winkler, A.; Pekdeger, A.

1994-01-01

The influence of microbial activity on the transport and migration behaviour of redox-sensitive radionuclides (e.g. Technetium (T c ) and Selenium (Se)) in groundwater environment were investigated within an interdisciplinary research program. Soil material and sediments were investigated with batch- and recirculation column experiments. The number of microorganisms in the water was determined by counting the colony forming units (CFU) on R2A agar at regular periods. The results of sterile and non sterile recirculation column experiments showed within 80 days a high fixation of the radionuclides in the unsterile samples (80% of T c , 50% of Se compared with the initial concentration A 0 ), and no fixation in the sterile samples. There was no difference in the redox values. It could be shown that the immobilisation of the redox-sensitive elements T c and Se are strongly determined by microbial activity, depending on the different sediments and their microbial live stock. There are indications that the microorganisms found in the non sterile columns are allochthonous bacteria which were dragged into the experimental systems and samples during laboratory work and sampling. The composition of the microbial flora was shown to be very heterogeneous and different in each individual column and within the same column at different times. Thus these columns might have been contaminated with microorganisms during sampling and handling of the experimental systems under non sterile conditions, as done generally in most laboratories

Natural radionuclides in coal and waste material originating from coal fired power plant

International Nuclear Information System (INIS)

Marovic, Gordana; Franic, Zdenko; Sencar, Jasminka; Petrinec, Branko; Bituh, Tomislav; Kovac, Jadranka

2008-01-01

This paper presents long-term investigations of natural radioactivity in coal, used for power production in the coal-fired power plant (CFPP) situated on the Adriatic coast, and resulting slag and ash. Activity concentrations of 40 K, 232 Th, 226 Ra and 238 U in used coal and resulting waste material have been measured for 25 years. As expected, it was demonstrated that the content of radionuclides in deposited bottom and filter ash material are closely related with radionuclide activity concentrations and mineral matter fraction in used coals. The external hazard index has been calculated and discussed for the slag and ash depository. During the first decade of operation of the CFPP has been used domestic coal produced in nearby area characterized by higher background radiation compared with the rest of Croatia. Therefore, the coal itself had relatively high 226 Ra and 238 U activity concentrations while potassium and thorium content was very low, 40 K activity concentrations being 2-9% and those of 232 Th 1-3% of total activity. As, in addition, the sulphur concentrations in coal were very high use of domestic coal was gradually abandoned till it was completely substituted by imported coal originated from various sources and of low natural radioactivity. Upon this, activity concentrations of uranium series radionuclides in deposited waste materials decreased significantly. Consequently, waste material i.e., slag and ash, generated in the last several years of coal fired power plant operation could be readily used in cement industry and as additive to other building materials, without any special restrictions according to the Croatian regulations dealing with building materials and European directives. (author)

Radionuclide contents in food products from domestic and imported sources in Nigeria

International Nuclear Information System (INIS)

Jibiri, N N; Okusanya, A A

2008-01-01

Samples of some domestic and imported food products of nutritive importance to both the child population and the adult population in Nigeria were collected and analysed in order to determine their radionuclide contents. The samples were collected from open markets in major commercial cities in the country. Gamma-ray spectrometry was employed in the determination of the radionuclide contents in the products. The gamma-ray peaks observed with reliable regularity in all the samples analysed belong to naturally occurring radionuclides, namely 226 Ra, 228 Th and 40 K. The activity concentrations of these radionuclides in both the domestic and imported products were observed to be not significantly different. Essentially radioactive elements such as 137 Cs were not detected in any of the samples. The non-detection of 137 Cs in the imported products may be attributed to the suitably modified agricultural practices and countermeasures being employed to reduce caesium uptake by plants after the Chernobyl nuclear reactor accident. It seems unlikely that the elemental concentrations in the food products analysed will contribute significantly to public health risks in the country, as the cumulative ingestion effective dose values from 226 Ra and 228 Th were found to be low. Although 40 K has the highest activity concentrations in all the samples analysed, it is usually under homeostatic control in the body, and hence the concentrations are irrelevant to possible contamination in the food products analysed. (note)

Automatic procedure go keep updated the activity levels for each radionuclide existing in a radioactivity laboratory

International Nuclear Information System (INIS)

Los Arcos, J.M.

1988-01-01

An automatic procedure to keep updated the activity levels each radionuclide existing in a radioactivity laboratory, and its classification according to the Spanish Regulations on Nuclear and Radioactive Establishments is described. This procedure takes into account the mixed composition of each source and whether it is sealed or the activity and mass variation due to extraction or evaporation in non-sealed sources. For a given date and time, the procedure prints out a complete listing of the activity of each radioactive source, the accumulated activity for each radionuclide, for each kind of radionuclide and the actual classification of the laboratory according to the legal regulations above mentioned. (Author)

Natural radionuclides in soil profiles surrounding the largest coal-fired power plant in Serbia

OpenAIRE

Tanić Milan N.; Janković-Mandić Ljiljana J.; Gajić Boško A.; Daković Marko Z.; Dragović Snežana D.; Bačić Goran G.

2016-01-01

This study evaluates the influence of the largest Serbian coal-fired power plant on radionuclide concentrations in soil profiles up to 50 cm in depth. Thirty soil profiles were sampled from the plant surroundings (up to 10 km distance) and analyzed using standard methods for soil physicochemical properties and gamma ray spectrometry for specific activities of natural radionuclides (40K, 226Ra and 232Th). Spatial and vertical distribution of radionuclides wa...

Radionuclide characterization of environmental air around nuclear facilities

International Nuclear Information System (INIS)

Gede Sutresna Wijaya; Anung Muharini

2015-01-01

Air is an important environmental component in human life. Presence of air pollutants or contaminants will have a negative impact on human health. According to the existence of a nuclear facility in Yogyakarta, the characterization of radionuclides in the air is absolutely necessary to ensure the safety of people and the environment and also to supervise the safe operation of the facility. In this research the characterization of radionuclides in the air was carried through the air sampling by using High Volume Air Sampler equipped with filter TFA 2133, followed by analysis using combination of a gamma and alpha spectrometers. The concentration of radioactivity in the air fluctuates depending on the time and duration of sampling. Characterization of gamma emitting radionuclides in the air is dominated by radon progeny radionuclides such as 214 Pb, 214 Bi with activity 20.09 ± 1.23 until 32.91 ± 4.87 Bq/m 3 and 31.22 ± 1.76 until 44.25 ± 4.91 Bq/m 3 . Alpha emitter radionuclide was dominated by 214 Po (7.69 MeV) which is also radon progeny and a primordial radionuclides. It can be concluded that the presence of radionuclides in the environmental air not as a product resulting from the operation of nuclear facilities in Yogyakarta. (author)

Statistical analysis of fallout radionuclides transfer to paddy-field rice

International Nuclear Information System (INIS)

Takahashi, T.; Morisawa, S.; Inoue, Y.

1996-01-01

Radionuclides released from nuclear facilities to atmosphere are transported through various pathways in biosphere and cause human exposure. Among these radionuclides transfer pathways, an ingestion of crops containing radionuclides is one of the dominant pathway for human exposure. For the safety assessment of nuclear facilities, it is important to understand the behavior of radionuclides in agricultural environment and to describe them in a mathematical model. In this paper, a statistical model is proposed for estimating the concentration of fallout radionuclides in paddy-field rice, the staple food for Japanese people. For describing behavior of fallout radionuclides in a paddy-field, a dynamic model and a statistical model have been proposed respectively. The model used in this study has been developed assuming that the amount of radionuclides transfer to brown rice (hulled rice) or polished rice through direct deposition of airborne radionuclides (the direct deposition pathway) and root uptake from a paddy soil (the root uptake pathway) are proportional to the deposition flux of radionuclides and concentration of radionuclides in paddy soil respectively. That is, the model has two independent variables; the deposition flux of radionuclides and the concentration of radionuclides in the paddy soil, and has single dependent variable; the concentration of radionuclides in brown rice or polished rice. The regression analysis is applied by using environmental monitoring data. Then the distribution of radionuclides between rice-bran (skin part of rice crop) and polished rice (core part) through both the direct deposition pathway and the root uptake pathway are evaluated by the model. (author)

Inverse problem in radionuclide transport

International Nuclear Information System (INIS)

Yu, C.

1988-01-01

The disposal of radioactive waste must comply with the performance objectives set forth in 10 CFR 61 for low-level waste (LLW) and 10 CFR 60 for high-level waste (HLW). To determine probable compliance, the proposed disposal system can be modeled to predict its performance. One of the difficulties encountered in such a study is modeling the migration of radionuclides through a complex geologic medium for the long term. Although many radionuclide transport models exist in the literature, the accuracy of the model prediction is highly dependent on the model parameters used. The problem of using known parameters in a radionuclide transport model to predict radionuclide concentrations is a direct problem (DP); whereas the reverse of DP, i.e., the parameter identification problem of determining model parameters from known radionuclide concentrations, is called the inverse problem (IP). In this study, a procedure to solve IP is tested, using the regression technique. Several nonlinear regression programs are examined, and the best one is recommended. 13 refs., 1 tab

Radionuclide migration test using undisturbed aerated soil

International Nuclear Information System (INIS)

Yamamoto, Tadatoshi; Ohtsuka, Yoshiro; Ogawa, Hiromichi; Wadachi, Yoshiki

1988-01-01

As one of the most important part of safety assessment on the shallow land disposal of lowlevel radioactive waste, the radionuclide migration was studied using undisturbed soil samples, in order to evaluate an exact radionuclide migration in an aerated soil layer. Soil samples used in the migration test were coastal sand and loamy soil which form typical surface soil layers in Japan. The aqueous solution containing 60 CoCl 2 , 85 SrCl 2 and 137 CsCl was fed into the soil column and concentration of each radionuclide both in effluent and in soil was measured. Large amount of radionuclides was adsorbed on the surface of soil column and small amount of radionuclides moved deep into the soil column. Difference in the radionuclide profile was observed in the low concentration portion particularly. It is that some fractions of 60 Co and 137 Cs are stable in non-ionic form and move downward through the soil column together with water. The radionuclide distribution in the surface of soil column can be fairly predicted with a conventional migration equation for ionic radionuclides. As a result of radionuclide adsorption, both aerated soil layers of coastal sand and loamy soil have large barrier ability on the radionuclide migration through the ground. (author)

Technical basis for selecting radionuclide concentrations for use in Hanford tank basis for interim operation source term

International Nuclear Information System (INIS)

Cowley, W.L.

1997-01-01

This paper describes the development of a radiological source term for waste tanks at the Hanford Site Nuclear Reservation. It describes the methodology used to identify the most important radionuclides, determine appropriate concentrations, and define unit liter doses. An example of how unit liter doses are used is given

Activity concentrations of 239+240 Pu in sediment at Sabah and Sarawak coastal areas

International Nuclear Information System (INIS)

Jalal Sharib; Zaharudin Ahmad; Yii Mei Wo; Hidayah Shahar

2009-01-01

The coastal sediment sampling was carried out in July 2004 as part of the Marine Radioactivity Database Development Project for Malaysia. The determination of plutonium, 239+240 Pu activity concentration and their distributions along the coastal areas of Sabah and Sarawak was by the alpha spectrometry counting system. Prior to counting, the radionuclides were isolated from the samples using radiochemical separation technique and mounted on a stainless steel disc by using electro-deposition. The results show that the distribution of 239+240 Pu activity concentration in coastal sediment is consistent, ranging from BDL - 1.83 Bq/kg and 0.11 - 0.84 Bq/kg dry weight, respectively. Lubok Sabanan, SB 15, in Sabah and Sungai Similajau, SR 13, in Sarawak were sampling stations that gave highest 239+240 Pu activity concentration. Overall, the 239+240 Pu activity concentration of Sabah and Sarawak are slightly higher in comparison the West Coast coastal stations of Peninsular Malaysia, and can be used as database. (Author)

Stable elements and radionuclides in shoreline alder stands at Olkiluoto in 2005

International Nuclear Information System (INIS)

Roivainen, P.

2006-08-01

In Finland, the final disposal of spent nuclear fuel from Finnish nuclear power plants is to take place in a repository, which will be built in Olkiluoto bedrock. According to the current plans, operation of the facility will start in 2020. Before this, a safety case has to be drawn up to substantiate the safety of the final disposal solution. The drawing up of the safety case also involves an assessment of impact on organisms other than human. Several radionuclides have a stable chemical analogue. Chemical analogues often display similar behaviour in the forest ecosystem. For this reason, information about radionuclides can also be obtained by studying stable elements. The purpose of this thesis was to study the migration of elements, radionuclides in particular, in the food webs of the Olkiluoto forest ecosystem. The objective was to produce concentration ratios between the various sub-components of the forest ecosystem. These ratios can be utilised in modelling. Three alder stands on the shores of Olkiluoto were used as monitoring plots. Littoral alder stands are an important biotope in terms of a recipient of the potential radionuclide contamination from the repository. Yet, research on littoral alder stands has so far been quite limited. From all the monitoring plots, a sample was taken of humus, mineral soil, understorey, plant roots and forest litter. Small mammals and earthworms were also to be caught from the monitoring plots, but no earthworms could be caught in any of the areas. All the collected samples were analysed for element concentrations using the ICP-AES method. Soil and plant samples were also analysed with a gamma spectrometer for activity concentrations of gamma active radionuclides. Activity concentrations of Cs-137 and K-40 could be determined in all soil and plant samples. The highest activity concentration of Cs-137 was found in humus, and the lowest in mineral soil. The activity concentration of K-40 was at its highest in mineral soil and

Activities of radionuclides in the Pacific coastal area of Fukushima since the TEPCO Fukushima Daiichi Nuclear Power Station accident - Activities of radionuclides in the coast area off Fukushima after TEPCO's Fukushima Daiichi Nuclear Power Station accident

Energy Technology Data Exchange (ETDEWEB)

Aono, Tatsuo; Fukuda, Miho; Yoshida, Satoshi [National Institute of Radiological Sciences, 263-8555, Chiba (Japan); Sohtome, Tadahiro; Mizuno, Takuji [Fukushima Prefecture Fisheries Experimental Station, 970-0316, Fukushima (Japan); Igarashi, Satoshi [Fukushima Prefecture Fisheries Experimental Station, 970-0316, Fukushima (Japan); Fukushima Prefecture Sea-Farming Association, 970-8044, Fukushima (Japan); Ito, Yukari; Kanda, Jota; Ishimaru, Takashi [Tokyo University of Marine Science and Technology, 108-0075, Tokyo (Japan)

2014-07-01

The accident of TEPCO's Fukushima Daiichi Nuclear Power Station (FDNPS) has caused the release of the huge quantities of radionuclide by the 2011 Great East Japan Earthquake and Tsunami, and then the serious problems gave rise to pollution in marine environment widely in the coast area off Fukushima. Monitoring of radioactivity in seawater and biota are important for understanding the dispersion of radionuclides and the effects of radioecology in the marine environment around the coast of Fukushima and the Pacific. The activities of Cs-134 and Cs-137 in seawater decreased exponentially and then were almost same levels before the accident around off Fukushima after about three years from the accident. However, the high activities of radio caesium (Cs) have been monitored in marine biota off Fukushima. The aims of the present study were to examine the temporal changes in radioactivity and to clarify the variation factor and the effect of radioecology in marine biota. Cs-134 and Cs-137, and Ag-110m, were released by this accident, determined in biota sample such as the plankton, fish and benthos, although it is well-known that molluscs and crustaceans concentrate silver in visceral parts. However, Sr-90 was not detected and the activities of plutonium were almost same level before this accident in the marine biota around off Fukushima. Concentration ratios of Cs (CR-Cs) in marine organism were from 2.6 E+1 in the muscle part of squid to 1.0 E+4 in the viscera of clam. The large differences in CR-Cs by the parts of marine organism were not observed. It is suggested that rapid change in the activities of radio Cs and silver in seawater, resuspension of particles from sediments and food chain effects led to high radionuclide activities in marine biota after this accident. CR-Cs in plankton was also calculated with the activities in seawater, which were collected around sampling area during this monitoring period. These resulting values ranged from 5.8 E+1 to 7.8 E+2

Equilibrium concentration of radionuclides in cement/groundwater/carbon steel system

International Nuclear Information System (INIS)

Keum, D. K.; Cho, W. J.; Hahn, P. S.

1997-01-01

Equilibrium concentration of major elements in an underground repository with a capacity of 100,000 drums have been simulated using the geochemical computer code (EQMOD). The simulation has been carried out at the conditions of pH 12 to 13.5, and Eh 520 and -520 mV. Solubilities of magnesium and calcium decrease with the increase of pH. The solubility of iron increases with pH at Eh -520 mV of reducing environment, while it almost entirely exists as the precipitate of Fe(OH) 3 (s) at Eh 520 mV of oxidizing environment. All of cobalt and nickel are predicted to be dissolved in the liquid phase regardless of pH since the solubility limit is greater than the total concentration. In the case of cesium and strontium, all forms of both ions are present in the liquid phase because they have negligible sorption capacity on cement and large solubility under disposal atmosphere. And thus the total concentration determines the equilibrium concentration. Adsorbed amounts of iodide and carbonate are dependent on adsorption capacity and adsorption equilibrium constant. Especially, the calcite turns out to be a solubility-limiting phase on the carbonate system. In order to validate the model, the equilibrium concentrations measured for a number of systems which consist of iron, cement, synthetic groundwater and radionuclides are compared with those predicted by the model. The concentrations between the model and the experiment of nonadsorptive elements - cesium, strontium, cobalt, nickel and iron, are well agreed. It indicates that the assumptions and the thermodynamic data in this work are valid. Using the adsorption equilibrium constant as a free parameter, the experimental data of iodide and carbonate have been fitted to the model. The model is in a good agreement with the experimental data of the iodide system. (author)

Seasonal variations in activity concentrations of {sup 99}Tc and {sup 137}Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea

Energy Technology Data Exchange (ETDEWEB)

Copplestone, D. E-mail: copplest@liv.ac.uk; Jackson, D.; Hartnoll, R.G.; Johnson, M.S.; McDonald, P.; Wood, N

2004-07-01

Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of {sup 99}Tc, as a result of the treatment of previously stored waste, with consequent increases in {sup 99}Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of {sup 99}Tc and {sup 137}Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of {sup 99}Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of {sup 99}Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg{sup -1} (fresh weight (fw)) in crabs and 124 to 216 Bq kg{sup -1} (fw) in lobsters, with no observed seasonal variations. Activity concentrations of {sup 137}Cs in both crab and lobster were lower, ranging from <0.16 to 0.85 Bq kg{sup -1} for crab meat (fw) and <0.3 to 3.3 Bq kg{sup -1} for lobster meat (fw). A statistically significant increase in activity concentrations of {sup 137}Cs in the meat was observed in the summer months for both crab and

Radionuclides in marine mammals off the Portuguese coast

Energy Technology Data Exchange (ETDEWEB)

Malta, Margarida [Instituto Tecnologico e Nuclear, Departamento de Proteccao Radiologica e Seguranca Nuclear, E.N. 10, 2686-953 Sacavem (Portugal); Carvalho, Fernando P., E-mail: carvalho@itn.p [Instituto Tecnologico e Nuclear, Departamento de Proteccao Radiologica e Seguranca Nuclear, E.N. 10, 2686-953 Sacavem (Portugal)

2011-05-15

Radionuclide analyses were performed in tissue samples including muscle, gonad, liver, mammary gland, and bone of marine mammals stranded on the Portuguese west coast during January-July 2006. Tissues were collected from seven dolphins (Delphinus delphis and Stenella coeruleoalba) and one pilot whale (Globicephala sp.). Samples were analyzed for {sup 210}Po and {sup 210}Pb by alpha spectrometry and for {sup 137}Cs and {sup 40}K by gamma spectrometry. Po-210 concentrations in common dolphin's muscle (D. delphis) averaged 56 {+-} 32 Bq kg{sup -1} wet weight (w.w.), while {sup 210}Pb averaged 0.17 {+-} 0.07 Bq kg{sup -1} w.w., {sup 137}Cs averaged 0.29 {+-} 0.28 Bq kg{sup -1} w.w., and {sup 40}K 129 {+-} 48 Bq kg{sup -1} w.w. Absorbed radiation doses due to these radionuclides for the internal organs of common dolphins were computed and attained a 1.50 {mu}Gy h{sup -1} on a whole body basis. {sup 210}Po was the main contributor to the weighted absorbed dose, accounting for 97% of the dose from internally accumulated radionuclides. These computed radiation doses in dolphins are compared to radiation doses from {sup 210}Po and other radionuclides reported for human tissues. Due to the high {sup 210}Po activity concentration in dolphins, the internal radiation dose in these marine mammals is about three orders of magnitude higher than in man. - Highlights: {yields} In marine mammals the highest activity concentrations were those of {sup 40}K and {sup 210}Po. {yields} Absorbed radiation doses in dolphin tissues attained 1.50 mGy h{sup -1} on a whole body basis. {yields} Po-210 was the main contributor (97%) to the internal absorbed radiation dose. {yields} The high {sup 210}Po concentration in the marine mammal's tissues is due to food chain transfer. {yields} The absorbed radiation dose in dolphins is three orders of magnitude higher than in man.

Comparison of concentrations of natural and artificial radionuclides in Plankton from French Polynesian and Australian coastal waters

International Nuclear Information System (INIS)

Poletiko, C.; Twining, J.R.; Jeffree, R.A.

1994-01-01

Zooplankton samples from French Polynesian and Australian coastal waters were analysed for natural and artificial radionuclides. Quality control was assured by correlating replicate analyses between three laboratories and by participation in an international intercomparison exercise. Pu239/240 was detected sporadically among samples from both regions, with the highest levels being more consistently found in Tuamotu-Gambier samples. The artificial radionuclides Cs-137, Cs-134, Sr-90 and Co-60 were not detected. Of the natural nuclides, Ac-228 was detected in shallow continental waters off Northern Australia and an inverse relationship (P<0.02) was established between plankton density and their Po-210 concentration. (authors). 2 figs., 2 tabs., 9 refs

A new simplified allometric approach for predicting the biological half-life of radionuclides in reptiles

International Nuclear Information System (INIS)

Beresford, N.A.; Wood, M.D.

2014-01-01

A major source of uncertainty in the estimation of radiation dose to wildlife is the prediction of internal radionuclide activity concentrations. Allometric (mass-dependent) relationships describing biological half-life (T 1/2b ) of radionuclides in organisms can be used to predict organism activity concentrations. The establishment of allometric expressions requires experimental data which are often lacking. An approach to predict the T 1/2b in homeothermic vertebrates has recently been proposed. In this paper we have adapted this to be applicable to reptiles. For Cs, Ra and Sr, over a mass range of 0.02–1.5 kg, resultant predictions were generally within a factor of 6 of reported values demonstrating that the approach can be used when measured T 1/2b data are lacking. However, the effect of mass on reptilian radionuclide T 1/2b is minimal. If sufficient measured data are available for a given radionuclide then it is likely that these would give a reasonable estimate of T 1/2b in any reptile species. - Highlights: • An allometric approach to predict radionuclide T 1/2b values in reptiles is derived. • Predictions are generally within a factor of six of measured values. • Radionuclide biological half-life is in-effect mass independent

Sorption of radionuclides on a soil

International Nuclear Information System (INIS)

Fukui, Masami

1979-01-01

Disposal of radioactive wastes into the ground has been discussed, and this paper emphasized significance of the investigation for underground water flow and for the prediction of radionuclides through a stratified aquifer using column experiments to evaluate the internal radiation dose. Distributions and redistributions of radionuclides in a sandy layer were observed to identify the sorption model which predicts the behavior, and the underground water flow in the Plio-Pleistocene Osaka Group was investigated as an example, by mean of the measurement of 222 Rn concentration, the pumping technique and the tracer technique using the activation analysis. Then, the estimation of radioactive concentration in the underground water was worked out for the boundary condition of steady state inflow of liquid wastes and of which the 90 Sr are leached from the solidified body, moreover, the equation which easily evaluates the suitability of the disposal site was proposed. These approach may be useful for the actual site selection of radioactive wastes disposal. (author)

Radiocaesium activity concentrations in Potatoes in Croatia after the Chernobyl accident

International Nuclear Information System (INIS)

Franic, Z.; Marovic, G.

2006-01-01

In the paper are summarized the results of systematic investigations of 137 Cs and 134 Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period in the Republic of Croatia. Potatoes are very important foodstuff in Croatia, the average annual consumption being about 40 kg per person. Due to a comparatively high contribution of the ingestion doses to the total dose received by population after the exposure to nuclear fallout, a reliable prognosis of the expected ingestion doses is of utmost importance. The ingestion dose strongly depends on the consumption of various types of foodstuffs, and related activity concentrations of respective radionuclides in those foodstuffs, which themselves usually depend upon the transfer from fallout. In addition, a reliable prediction of the expected ingestion dose received by consumption of a particular foodstuff requires the detailed knowledge of decreasing behaviour of activity concentrations in the environment and respective foodstuffs. The correlation between 137 Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r2=0.88 with P(t) < 0.001 for 17 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of 137 Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.3 ± 0.8 years, the standard deviation being estimated by the Monte Carlo simulations. The initial observed 134 Cs:137 Cs activity ratio in potatoes has been found to be quite variable, but slightly lesser than theoretically predicted value of 0.5, calculated by applying the known inventory of these radionuclides in the Chernobyl reactor to the equation for the differential radioactive decay. This can be explained by presence of the pre-Chernobyl 137 Cs in soil that originated from nuclear fallout. As in other environmental samples, 134

Biota sediment concentration ratio (CRs-b) for fishes of Rana Pratap Sagar Lake, Rawatbhata

International Nuclear Information System (INIS)

Goyal, S.K.; Srivastava, A.P.; Jain, A.K.; Meenal, Balram; Tiwari, S.N.; Ravi, P.M.; Tripathi, R.M.

2018-01-01

Radionuclides dissolved in water can be adsorbed by bottom/shore sediment transferring it to the deep sediment layers. These adsorbed radionuclides can be remobilized and be available again for uptake by freshwater biota. The biota sediment concentration ratio (CR s-b ) is the ratio of the concentration of a radionuclide in an organism (C b ) on a fresh weight basis to the radionuclide concentration measured in the sediment (C sediment ). Using the data of 137 Cs activity in fish and shore sediment, CR s-b was calculated for fish samples of Rana Pratap Sagar (RPS) Lake, Rawatbhata. This value can be applied in predictive models to calculate radionuclide concentration in fish samples

Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

Energy Technology Data Exchange (ETDEWEB)

Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A.; Brunk, J.A.

1986-07-01

This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, /sup 137/Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of /sup 137/Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. /sup 90/Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of /sup 60/Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of /sup 60/Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of /sup 207/Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of /sup 207/Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, /sup 207/Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of /sup 207/Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither /sup 239 +240/Pu nor /sup 241/Am is significantly accumulated in the muscle tissue of any species of fish. Apparently, /sup 238/Pu is in a more readily available form for accumulation by fishes than /sup 239 +240/Pu. Based on a daily ingestion rate of 200 q of fish flesh, dose rates to individuals through the fish-food ingestion pathway are well below current Federal guidelines.

Natural Radionuclides and Heavy Metals Pollution in Seawater at Kuala Langat Coastal Area

International Nuclear Information System (INIS)

Sabarina Md Yunus; Zaini Hamzah; Ab Khalik Hj Wood; Ahmad Saat

2015-01-01

Rapid industrial developments along the Langat river basin play an important role in contributing to the increases of pollution loading at Kuala Langat coastal area. The major pollutant sources in this area may be originating from human activities such as industrial discharge, domestic sewage, construction, agriculture and pig farming near the tributaries that affects the water quality. In addition, Langat and Semenyih rivers flow through the mining and ex-mining area, which is related to the source of natural radionuclides contamination. Heavy metals in the aquatic environment and more likely to enter the food chain. This study is focusing to the levels of radionuclides and heavy metals in seawater. The samples were collected using appropriate water sampler, which is then acidified until pH 2 and filtered using cellulose acetate 0.45 μm. The concentration of these radionuclides and heavy metals were determined using Inductive Coupled Plasma Mass Spectrometer (ICPMS) after dilution. In general, the radionuclides and heavy metals concentrations are lower than Malaysia Marine Water Quality Standard (MMWQS) except for few locations where the concentration levels above the standards. The higher concentration of pollutant in the seawater may have a toxic effect on sensitive plants and living organisms. The results of pollution levels of these radionuclides and heavy metals were also compared with other studies. (author)

Concentration and distribution patterns of naturally occurring radionuclides in sediments and flood plain soils of the catchment area of the river Elbe

International Nuclear Information System (INIS)

Barth, A.; Jurk, M.; Weiß, D.

1998-01-01

The impact of uranium mining and milling as well as that of traditional mining activities on river sediments and flood plain soils in the catchment area of the river Elbe was investigated over the years 1994 to 1995. Contamination resulting from mining activities has been identified by comparing the median values for the measured radionuclides, and by establishing the ratio between Ra-226 and Ra-228. The transport and deposition of contaminated materials as a result of high water events, and river discharge of waste water from mining and milling facilities, can be considered to be the main paths of sediment and soil contamination. Sediments and flood plain soils located in the vicinity of former uranium mining and milling sites are primarily influenced by discharges of waste water. Long distance transport and deposition at dams, barrages and on flood plains has mainly been caused by high water events. In many cases the radionuclide concentrations were higher in the subsurface layer than in the top layer of flood plain soil. Due to termination of uranium mining and milling activities, no significant contamination of newer or fresh sediments was found. Radiation exposure arising in relation to angling or walking on flood plains is low

A new approach to predicting environmental transfer of radionuclides to wildlife: A demonstration for freshwater fish and caesium

Energy Technology Data Exchange (ETDEWEB)

Beresford, N.A., E-mail: nab@ceh.ac.uk [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Av. Bailrigg, Lancaster LA1 4AP (United Kingdom); Yankovich, T.L. [Saskatchewan Research Council, Environment and Forestry, 125, 15 Innovation Blvd., Saskatoon, SK S7N 2X8 (Canada); Wood, M.D. [School of Environment and Life Sciences, Room 323, Peel Building, University of Salford, Manchester, M5 4WT (United Kingdom); Fesenko, S. [International Atomic Energy Agency, 1400 Vienna (Austria); Andersson, P. [Strålsäkerhetsnymdigheten, Swedish Radiation Safety Authority, SE-171 16 Stockholm (Sweden); Muikku, M. [STUK, P.O. Box 14, 00881 Helsinki (Finland); Willey, N.J. [Centre for Research in Biosciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol BS16 1QY (United Kingdom)

2013-10-01

The application of the concentration ratio (CR) to predict radionuclide activity concentrations in wildlife from those in soil or water has become the widely accepted approach for environmental assessments. Recently both the ICRP and IAEA have produced compilations of CR values for application in environmental assessment. However, the CR approach has many limitations, most notably, that the transfer of most radionuclides is largely determined by site-specific factors (e.g. water or soil chemistry). Furthermore, there are few, if any, CR values for many radionuclide-organism combinations. In this paper, we propose an alternative approach and, as an example, demonstrate and test this for caesium and freshwater fish. Using a Residual Maximum Likelihood (REML) mixed-model regression we analysed a dataset comprising 597 entries for 53 freshwater fish species from 67 sites. The REML analysis generated a mean value for each species on a common scale after REML adjustment taking account of the effect of the inter-site variation. Using an independent dataset, we subsequently test the hypothesis that the REML model outputs can be used to predict radionuclide, in this case radiocaesium, activity concentrations in unknown species from the results of a species which has been sampled at a specific site. The outputs of the REML analysis accurately predicted {sup 137}Cs activity concentrations in different species of fish from 27 Finnish lakes; these data had not been used in our initial analyses. We recommend that this alternative approach be further investigated for other radionuclides and ecosystems. - Highlights: • An alternative approach to estimating radionuclide transfer to wildlife is presented. • Analysed a dataset comprising 53 freshwater fish species collected from 67 sites. • Residual Maximum Likelihood mixed model regression is used. • Model output takes account of the effect of inter-site variation. • Successfully predicted {sup 137}Cs concentrations in

Determination of radionuclides in discharged water from gold ...

African Journals Online (AJOL)

The levels of radionuclides concentrations in discharged water from gold processing into the environment of Bogoso (Ghana) were determined using radioanalytical techniques. Radioactivity screening was first carried out to identify physical and chemical processing stages that might be concentrating the radionuclides.

Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

Science.gov (United States)

McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

Technogenic radionuclides of Chernobyl NPP accidental release and their physical and chemical forms

Directory of Open Access Journals (Sweden)

A. I. Lypska

2015-10-01

Full Text Available Distribution of radionuclides in the vertical soil profile on the nearest Chernobyl NPP zone of alienation was investigated. It is showed experimentally that the main activity of radionuclides is concentrated in the topsoil (10 сm. Coefficients of accumulation of 137Cs and 90Sr radionuclides by plants are estimated. The physico-chemical forms of radionuclides in soil and plants were defined using the method of sequential chemical extraction. It was established that the main contents of 137Cs and 90Sr in soils are represented in non-exchange and fixed forms, in plants - mainly in exchange-adsorption and organic forms.

The contamination of the oceans by anthropogenic radionuclides

International Nuclear Information System (INIS)

Figueira, Rubens C.L.; Cunha, Ieda I.L.

1998-01-01

Several hundreds of artificial of artificial radionuclides are produced as the result of human activities, such as the applications of nuclear reactors and particle accelerators, testing of nuclear weapons and nuclear accidents. Many of these radionuclides are short-lived and decay quickly after their production, but some of them are longer-lived and are released into the environment. From the radiological point of view the most important radionuclides are cesium-137, strontium-90 and plutonium-239, due to their chemical and nuclear characteristics. The two first radioisotopes present long half life (30 and 28 years), high fission yields and chemical behaviour similar to potassium and calcium, respectively. No stable element exists for plutonium-239, that presents high radiotoxity, longh half-life (24000 years) and some marine organisms accumulate plutonium at high levels. The radionuclides introduced into marine environment undergo various physical, chemical and biological processes taking place in the sea. These processes may be due to physical, dispersion or complicated chemical and biological interactions of the radionuclides with inorganic and organic suspend matter, variety of living organism, bottom sediments, etc. The behaviour of radionuclides in the sea depends primarily on their chemical properties, but it may also be influenced by properties of interacting matrices and other environmental factors. The major route of radiation exposure of man to artificial radionuclides occuring in the marine environment is through ingestion of radiologically contamined marine organisms. This paper summarizes the main sources of contamination in the marine environment and presents an overview covering the oceanic distribution of anthropogenic radionuclides in the FAO regions. A great number of measurements of artificial radioclides have been carried out on various marine environmental samples in different oceans over the world, being cesium-137 the most widely measured

Conditions and processes affecting radionuclide transport

Science.gov (United States)

Simmons, Ardyth M.; Neymark, Leonid A.

2012-01-01

Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

Radiological survey and assessment of associated activity concentration of the naturally occurring radioactive materials (NORM) in the Migori artisanal gold mining belt of southern Nyanza, Kenya

Energy Technology Data Exchange (ETDEWEB)

Odumo, O.B., E-mail: benodumoo@uonbi.ac.k [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Mustapha, A.O. [Department of Physics, University of Agriculture, P.M.B. 2240 Abeokuta (Nigeria); Patel, J.P.; Angeyo, H.K. [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya)

2011-06-15

A radiological survey and assessment was carried out at selected sites (Osiri, Mikei, Masara and Macalder) in the Migori gold mines of southern Nyanza, Kenya to determine the levels of exposure of the artisanal miners to the naturally occurring radioactive materials (NORM) and dust. The activity concentrations of {sup 40}K and the decay products of {sup 232}Th and {sup 226}Ra were obtained using an innovative method in single channel NaI(Tl) gamma-ray spectrometry. The counts for both the sample and the reference material in a specific window for a particular radionuclide were compared to arrive at the activity concentration of the radionuclide in the sample. Measurement of dust loading at various crushing sites was carried out by trapping the dust particles on a 0.45 {mu}m cellulose acetate filter paper (47 mm diameter) using a vacuum pump. The activity concentration levels range widely 80-413, 12-145 and 21-258 Bq/kg for {sup 40}K, {sup 232}Th and {sup 226}Ra, respectively. The calculated absorbed dose in air range from 16 to 178 nGy/h (with a mean of 42 nGy/h). Dust loading was found to range from 1.3 to 3.7 mg/m{sup 3}. Although the activity concentration of the radionuclides and the calculated annual absorbed dose is below the world's average, the dust level at the mines was relatively high. The results obtained show that the artisanal miners are exposed to various levels of radionuclides and dust and necessary precautions need to be taken.

Radionuclide content of local and imported cements used in Egypt

International Nuclear Information System (INIS)

Mahmoud, K R

2007-01-01

The activity concentrations of natural and artificial gamma-ray emitting radionuclides in local and imported cement have been investigated during the period from 2000 to 2003 using a 50% HPGe γ-spectroscopy system. The total numbers of local and imported samples were 29 and 8, respectively. The results showed a low activity concentration of 137 Cs in both the local and imported samples. The only exception was found in one imported Portland cement (2.8 ± 0.2 Bq kg -1 ) and one local blast furnace slag cement (1.9 ± 0.3 Bq kg -1 ). The average activity concentrations of 226 Ra, 232 Th and 40 K in local cement were 33 ± 17, 14 ± 2.4 and 45 ± 26 Bq kg -1 , respectively, whereas those in imported cement were 27 ± 7, 8 ± 7 and 134 ± 22 Bq kg -1 , respectively. The results showed that blast furnace slag cement contains the highest level of natural radioactivity, whereas white cement contains the lowest levels. The measured activity concentrations of the detected radionuclides were compared with other measurements carried out in Egypt and elsewhere. Radium-equivalent activities were also calculated to assess the radiation hazards arising from using such material in the construction of dwellings. Generally, the radium-equivalents of the analysed samples were smaller than the guideline limit of 370 Bq kg -1

Distribution of radionuclides in soil samples from a petrified wood forest in El-Qattamia, Cairo, Egypt

International Nuclear Information System (INIS)

Nada, A.; Abd-El Maksoud, T.M.; Abu-Zeid Hosnia, M.; El-Nagar, T.; Awad, S.

2009-01-01

The concentrations and distribution of radionuclides in a petrified wood forest in El-Qattamia have been determined using high-resolution gamma spectrometry to evaluate the environmental radioactivity. The mean activity concentrations of 238 U, 232 Th and 40 K were 65.26±12.99, 23.66±0.95 and 146.33±1.50 Bq kg -1 , respectively. Data of the soil samples show evidence of possible deposition and accumulation of 137 Cs. The mean activity concentration of 137 Cs in the soil samples was 4.37±0.16 Bq kg -1 with a range of 0.00-35.70 Bq kg -1 . The measured activity concentration range of 137 Cs was compared with reported ranges in the literature from some of the other locations in the world. The radium-equivalent, dose rate in air and annual effective dose rate were evaluated. The mean activity concentrations of the γ-ray emissions from radionuclides in El-Qattamia petrified wood forest region were relatively low

The uptake of radionuclides from inadvertent consumption of soil by grazing animals

International Nuclear Information System (INIS)

Green, N.; Dodd, N.J.

1988-01-01

Investigations of the transfer to man of artificially-produced radionuclides through food chains have shown that the inadvertent consumption of soil by grazing animals can give variations in estimates of transfer coefficients, especially for radionuclides that are poorly absorbed by plant roots. Even small masses of soil adhering to herbage or directly ingested can make a significant contribution to the intake inventory in terms of activity. Although the activity concentrations of soil-contaminated herbage are elevated, the radionuclides associated with the soil may not necessarily be in a form which is easily absorbed by the animal. Attempts must be made, therefore, to quantify soil intake and the subsequent radionuclide uptake by this mechanism. A field investigation of the uptake of radionuclides by farm animals grazing near the Sellafield nuclear reprocessing plant has been pursued. The aims of the study were to estimate the transfer to muscle and other tissues. This paper describes the methods used to estimate both the soil intake and the consequent availability of radionuclides associated with the soil. The measurements were used to evaluate the contribution to tissue content of inadvertent consumption of soil by cows and sheep. 10 refs.; 2 tabs

Polonium-210 activity concentration, transfer and dose to certain invertebrates found in the vicinity of the Kudankulam Nuclear Power Project, Tamil Nadu, India

International Nuclear Information System (INIS)

Benjamin, J.; Wesley, S.G.; Rajan, M.P.

2013-01-01

Invertebrates are significant reference organisms, and some of them tend to accumulate certain radionuclides in increased levels. It is imperative that the levels of radionuclides are measured in certain organism in the vicinity of any major nuclear power project before its commissioning; hence, this study was carried out in the surroundings of the Kudankulam Nuclear Power Project site. The natural radionuclide polonium-210 having affinity to the organic matter in the soil and to the protein content of the animals, is very significant as it delivers a high internal dose to the organisms. The activity concentration of this radionuclide, its transfer and dose were assessed in two terrestrial (earthworm, Pheretima posthuma and land snail, Trachea vittata) and two aquatic (apple snail, Pila globosa and bivalve mollusc, Lamellidens marginalis) invertebrates. The activity concentration of 210 Po was found to be the highest in the earthworm and the lowest in the land snail. The per-animal dose due to 210 Po was the highest for the apple snail and the lowest for the earthworm. The results indicate that 210 Po does not constitute a significant radiological threat to the organisms. (author)

Radionuclide Concentration in Soils and Vegetation at Low-Level Radioactive Waste Disposal Area G during 2005

International Nuclear Information System (INIS)

Fresquez, P.R.; McNaughton, M.W.; Winch, M.J.

2005-01-01

Soil samples were collected at 15 locations and unwashed overstory and understory vegetation samples were collected from up to nine locations within and around the perimeter of Area G, the primary disposal facility for low-level radioactive solid waste at Los Alamos National Laboratory (LANL). Soil and plant samples were also collected from the proposed expansion area west of Area G for the purpose of gaining preoperational baseline data. Soil and plant samples were analyzed for radionuclides that have shown a history of detection in past years; these included 3 H, 238 Pu, 239,240 Pu, 241 Am, 234 U, 235 U, and 238 U for soils and 3 H, 238 Pu, and 239,240 Pu for plants. As in previous years, the highest levels of 3 H in soils and vegetation were detected at the south portion of Area G near the 3 H shafts; whereas, the highest concentrations of the Pu isotopes were detected in the northern and northeastern portions near the pads for transuranic waste. All concentrations of radionuclides in soils and vegetation, however, were still very low (pCi range) and far below LANL screening levels and regulatory standards

Atmospheric radionuclides from the Fukushima Dai-ichi nuclear reactor accident observed in Vietnam

International Nuclear Information System (INIS)

Long, N.Q.; Giap, T.V.; Phan, N.T.; Truong, Y.; Binh, N.T; Sieu, L.N.; Hien, P.D.

2012-01-01

Radionuclides from the reactor accident at the Fukushima Dai-ichi Nuclear Power Plant were observed in the surface air at stations in Hanoi, Dalat and Ho Chi Minh City (HCMC) in Vietnam, about 4500 km southwest of Japan, during the period from March 27 to April 22, 2011. The maximum activity concentrations in the air measured at those three sites were 193, 33 and 37 μBq m -3 for 131 I, 134 Cs and 137 Cs, respectively. Peaks of radionuclide concentrations in the air corresponded to arrival of the air mass from Fukushima to Vietnam after traveling for 8 days over the Pacific Ocean. Cesium-134 was detected with the 134 Cs/ 137 Cs activity ratio of about 0.85 in line with observations made elsewhere. The 131 I/ 137 Cs activity ratio was observed to decrease exponentially with time as expected from radioactive decay. The ratio at Dalat, where is 1500 m high, was higher than those at Hanoi and HCMC in low lands, indicating the relative enrichment of the iodine in comparison to cesium at high altitudes. The time-integrated surface air concentrations of the Fukushima-derived radionuclides in the Southeast Asia showed exponential decrease with distance from Fukushima. (author)

Inclusion of radionuclides absorption by sediments in the RIVLAK program

International Nuclear Information System (INIS)

Rodrigues Junior, O.; Moreira, J.M.L.

1992-01-01

The RIVLAK code solves the one-dimensional transport equation for radionuclide concentrations within a water body for routine and accidental releases of liquid effluents. The principal phenomena considered in the RIVLAK code are advection by the water body flow, longitudinal and transversal diffusion, and radioactive decay. This work incorporates the interaction between radionuclides and suspended or bed sediments to the RIVLAK code. An approximate equation for the radionuclide concentration in an effective sediment is included in the code with explicit terms for adsorption and desorption from the water to the effective sediment. The modified RIVLAK code is utilized for estimating the radionuclide concentration from release experiments in the Clinch river. The original code overestimates the Cs concentration downstream by approximately two orders of magnitude. The modified version predicts the Cs concentration with few percents, and underestimates its longitudinal dispersion by about 35%. The special care needed with parameters such as the radionuclide diffusion coefficient in the water, and the adsorption and desorption coefficients are discussed. (author)

Radionuclide concentrations in vegetation at radioactive-waste disposal Area G during the 1994 growing season

International Nuclear Information System (INIS)

Fresquez, P.R.; Biggs, J.B.; Bennett, K.D.

1995-01-01

Overstory (pinon pine) and understory (grass and forb) vegetation samples were collected within and around selected points at Area G-a low-level radioactive solid-waste disposal facility at Los Alamos National Laboratory-for the analysis of tritium ( 3 H), strontium ( 90 Sr), plutonium ( 238 Pu and 239 Pu), cesium ( 137 Cs), americium ( 241 Am), and total uranium. In general, most vegetation samples collected within and around Area G contained radionuclide levels in higher concentrations than vegetation collected from background areas. Tritium, in particular, was detected as high as 5,800 pCi/mL in overstory vegetation collected outside the fence just west of the tritium shafts; this suggests that tritium is migrating from this waste repository through subsurface pathways. Also, understory vegetation collected north of the transuranic (TRU) pads (outside the fence of Area G) contained the highest values of 90 Sr, 238 Pu, 239 Pu, 137 Cs, and 241 Am, and may be a result of surface holding, storage, or disposal activities

ORION: a computer code for evaluating environmental concentrations and dose equivalent to human organs or tissue from airborne radionuclides

International Nuclear Information System (INIS)

Shinohara, K.; Nomura, T.; Iwai, M.

1983-05-01

The computer code ORION has been developed to evaluate the environmental concentrations and the dose equivalent to human organs or tissue from air-borne radionuclides released from multiple nuclear installations. The modified Gaussian plume model is applied to calculate the dispersion of the radionuclide. Gravitational settling, dry deposition, precipitation scavenging and radioactive decay are considered to be the causes of depletion and deposition on the ground or on vegetation. ORION is written in the FORTRAN IV language and can be run on IBM 360, 370, 303X, 43XX and FACOM M-series computers. 8 references, 6 tables

Natural radionuclides concentration in agricultural products and water from the Monte Alegre region

International Nuclear Information System (INIS)

Gouvea, Vandir A.; Melo, Vicente P.; Binns, Donald A.C.; Santos, Pedro L. dos

1997-01-01

Measurements to determine the content of natural radionuclides were performed in agricultural products in the brazilian Central Amazon Basin Monte Alegre region, for the soil-plant transfer calculation. these measurements were concentrated in the Ingles de Souza agricultural settlement, were several uranium and thorium occurrences exist in geological formations called Monte Alegre and Faro. The values obtained in foodstuff cultivated in the anomalous region are 10 times higher than those ones observed in the Alenquer region, which is the chosen region due to its low level natural radioactivity and its proximity to the anomalous region. (author). 9 refs., 4 tabs

Sediment Ksub(d)s and concentration factors for radionuclides in the marine environment

International Nuclear Information System (INIS)

1985-01-01

Both the biological and geochemical processes, which are dependent on the chemical form of the element in question, and the radioactive decay of the nuclide are important parameters in the models used for the calculation of dumping limits for radioactive wastes disposed of in the deep sea. The geochemical processes were not adequately represented in earlier models and only rough approximations of parameters were used in the calculations. This report provides an approach for the calculation of deep-sea sediment distribution coefficients and coastal sediment concentration factors for radionuclides in marine biological materials based, whenever possible, on field data

Status of operation of radionuclides assay system in Korean nuclear power plant

International Nuclear Information System (INIS)

Hwang, K.H.; Lee, K.J.; Jeong, C.W.; Ahn, S.M.

2003-01-01

In Korea, 17 nuclear power plants composed of 13 pressurized water reactors and 4 CANDU reactors are currently in operation. The cumulative amounts of low and intermediate level radioactive waste in nuclear power plant reached 58,718 drums (unit: 200 liter) in 2001. Efforts to construct LILW disposal facility are continued and its first operation is planned in the year 2008. Its first stage capacity is assumed to be 100,000 drums and total capacity will reach to 800,000 drums. Radwaste disposal site selection is an urgent national project at present time. Regulations and guidelines require detailed information about the radioactive waste package and its contents prior to the transport to the disposal sites. The Enforcement Decree of the Korean Atomic Energy Act (articles 234-17) requires the Minister of Science and Technology (MOST) of Korea to establish regulation for the waste acceptance (MOST notice. 1196-10). It requires detailed information about the radioactive waste package and its contents such as activity of radionuclides, total activities, types and characteristics of waste. For the measurement of the concentrations and activities of radionuclides in radwaste drum, a radionuclides assay system is installed at Korean nuclear power plant (KORI site) in 1996. The waste drum can be measured in the vertical direction with eight vertical segments while in the radial direction also with eight segments. Using this measurement method, homogeneous and non-homogeneous waste drum can be measured. Scaling factor methods have been played a dominant role in the determination of the radionuclides concentration in this system. For corrosion product, generic scaling factors were used due to the similarity and better-characterized properties of Korean analyzed data as compared with the worldwide data base of PWR industry. For fission product and TRU nuclides, it is not easy to determine the generic scaling factors. Thus simple model reflecting the operation history of power

Concentration peculiarities of radionuclides by freshwater molluscs of Chernobyl NPP exclusion zone

International Nuclear Information System (INIS)

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

2001-01-01

The results of radionuclides 90 Sr and 137 Cs content in molluscs tissue of water objects within Chernobyl NPP exclusion zone has been analysed. The age dynamics of radionuclides content in some species of Gastropoda was studied

Vertical distribution of radionuclides in soil

International Nuclear Information System (INIS)

Bikit, I.; Slivka, J.; Krmar, M.; Chonkic, Lj.; Veskovic, M.; Hadzhic, V.

1990-01-01

Pedological profiles were opened at selected representative locations on different geomorphic types and in certain soil layers down to 3 m depth. The mechanical composition, hydro physical and chemical features were studied. The vertical distribution of naturally occurring radionuclides and 137 Cs was analyzed during 1988 and 1989. The parameter alpha of the exponential dependence of activity concentration vs. depth were calculated for the three soil types, as well as the activity concentration of 137 Cs at depths of 1 and 3 m. The extent of 137 Cs migration was evaluated at these depths and it is shown that the coefficient α is proportional to the reciprocal of the time elapsed from the surface contamination. (author)

Natural radionuclides in soil profiles surrounding the largest coal-fired power plant in Serbia

Directory of Open Access Journals (Sweden)

Tanić Milan N.

2016-01-01

Full Text Available This study evaluates the influence of the largest Serbian coal-fired power plant on radionuclide concentrations in soil profiles up to 50 cm in depth. Thirty soil profiles were sampled from the plant surroundings (up to 10 km distance and analyzed using standard methods for soil physicochemical properties and gamma ray spectrometry for specific activities of natural radionuclides (40K, 226Ra and 232Th. Spatial and vertical distribution of radionuclides was determined and analyzed to show the relations between the specific activities in the soil and soil properties and the most influential factors of natural radionuclide variability were identified. The radiological indices for surface soil were calculated and radiological risk assessment was performed. The measured specific activities were similar to values of background levels for Serbia. The sampling depth did not show any significant influence on specific activities of natural radionuclides. The strongest predictor of specific activities of the investigated radionuclides was soil granulometry. All parameters of radiological risk assessment were below the recommended values and adopted limits. It appears that the coal-fired power plant does not have a significant impact on the spatial and vertical distribution of natural radionuclides in the area of interest, but technologically enhanced natural radioactivity as a consequence of the plant operations was identified within the first 1.5 km from the power plant. [Projekat Ministarstva nauke Republike Srbije br. III43009 i br. III41005

Trends in radionuclide concentrations in Hanford Reach fish, 1982 through 1992

International Nuclear Information System (INIS)

Poston, T.M.

1994-06-01

Environmental monitoring has been conducted at the US Department of Energy's Hanford Site in southeast Washington State since 1945. Fish from the Hanford Reach of the Columbia River, which borders the Site, are monitored annually. The two objectives of this report were (1) to evaluate trends in the concentrations of radionuclides [e.g., 90 Sr and 137 Cs] in two species of Columbia River fish [smallmouth bass and mountain whitefish] sampled from the Hanford Reach from 1982 through 1992; and (2) to determine the impact of Hanford Site releases on these two species and carp and fall chinook salmon collected during this time frame. The evaluation found gradual reductions of 137 Cs in bass muscle and 90 Sr in bass and whitefish carcass from 1982 through 1992. Concentrations of 90 Sr in bass and whitefish followed the pattern established by reported Hanford Site releases from 1982 through 1992 and was supported by significant regression analyses comparing annual releases to sample concentration. Because data for carp have been collected only since 1990, the data base was inadequate for determining trends. Moreover, fall chinook salmon were only sampled once in this 11-year period. Concentrations of 90 Sr and 137 Cs in fish samples collected from distant background locations exceeded concentrations in Hanford Reach fish. Estimates of the dose from consumption of Hanford Reach fish were less than 0.001 times the National Council on Radiation Protection and Measurements and the US Department of Energy guideline of 100 mrem/yr

Behaviors and chemical forms of radionuclides in seawater

International Nuclear Information System (INIS)

Honda, Yoshihide

1981-01-01

Although the radionuclides introduced into the marine environment from various sources and routes are finally distributed among the components of the marine ecosystem, the residence time is one of the most useful measures of the reactivity of an element in the oceanic chemical system. Heavy metals such as Mn, Fe, Co and Zn which have shorter residence times, reveal more complicated behaviours in relation to marine radioecological interest than alkaline earth element such as Sr which has a longer residence time. The possible physico-chemical forms of radionuclides in the oceans are usually classified into three categories, that is, species in true solution, colloidal species, and particulate forms. The modeling to study the dispersion of radionuclides introduced into the marine environment can be approached with the aid of the knowledge of behaviors of their stable counterparts in seawater. The different physico-chemical forms between stable and radioactive nuclides in seawater may cause different biological concentration of the element. To realize the chemical speciation of radionuclides in the marine environment, it is also important in thermodynamical calculation to consider heterogeneous interfaces where cause raising the concentration of reactants in seawater, especially in the coastal waters. In the discussion on the primary factors that can affect the elemental distribution in the marine environment, primary productivity and bacterial activity are emphasized for the transformation of physicochemical states of radionuclides in the marine environment. Finally, the radioecological differences between radiocobalt in organic complexed and ionic forms were demonstrated in the experiments on the uptake and elimination of radiocobalt by mussels. (J.P.N.)

Transfer of radionuclides to plants[Radioecology

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Sven P. [Risoe National Lab., Roskilde (Denmark)

2006-04-15

Sampling of Water Horsetail and Bracken Fern including upper soil layer (0-10 cm) and water was carried out in Torahult, Sweden, in Almindingen on Bornholm, in Asserbo and Arresoe on Zealand and in Sdr. Hostrup and Nydam mose in Jutland. Furthermore, sampling was carried out in 2004 for seawater, seaweed and shrimps at locations in Danish waters at Bornholm (Svenskehavn), at Zealand (Klint), at Lolland/Falster (Guldborgsund) and on the west coast of Jutland (Hirtshals, Agger, Hvide Sande and Roemoe). Concentrations of gamma-emitting radionuclides and uranium were determined in Bracken Fern, Water Horsetail and soil samples. The concentration ratios (CR) are highest for {sup 40}K in both plant species and show the lowest variability across locations. The CR's for 40K range from 1 to 2, while the CR's for the other radionuclides range one to three orders of magnitude lower. The CR's for {sup 137}Cs show particularly high variability across locations. The CR's were analysed in a two-way ANOVA on the log-transformed values to test differences between plant species and radionuclides. The difference between radionuclides was highly significant, p<0.01, whereas the difference between plant species was not significant. The concentration ratios are listed by radionuclide showing geometric mean values and geometric standard deviations. Analyses were made of {sup 137}Cs and {sup 99}Tc in marine samples. Concentration ratios calculated from the analysed samples are presented. The concentration ratios for {sup 99}Tc agree with those reported elsewhere in the Indofern Project. The concentration ratios for {sup 137}Cs in Fucus show a correlation to salinity with higher values in low salinity water at Bornholm than in high salinity water on the west coast of Jutland. (LN)

Hydrology/Radionuclide Migration Program and related research activities

International Nuclear Information System (INIS)

Jones, M.A.

1992-02-01

This report presents the results of technical studies conducted under the Hydrology/Radionuclide Migration Program (HRMP) at the Nevada Test Site (NTS) for the period of October 1, 1985 through September 30, 1986. The HRMP was initiated in 1973 as the Radionuclide Migration Program to study and better understand the hydrologic systems of the NTS and potential movement and rates of movement of radionuclides and other contaminants injected into these systems by underground nuclear testing

A new general dynamic model predicting radionuclide concentrations and fluxes in coastal areas from readily accessible driving variables

International Nuclear Information System (INIS)

Haakanson, Lars

2004-01-01

This paper presents a general, process-based dynamic model for coastal areas for radionuclides (metals, organics and nutrients) from both single pulse fallout and continuous deposition. The model gives radionuclide concentrations in water (total, dissolved and particulate phases and concentrations in sediments and fish) for entire defined coastal areas. The model gives monthly variations. It accounts for inflow from tributaries, direct fallout to the coastal area, internal fluxes (sedimentation, resuspension, diffusion, burial, mixing and biouptake and retention in fish) and fluxes to and from the sea outside the defined coastal area and/or adjacent coastal areas. The fluxes of water and substances between the sea and the coastal area are differentiated into three categories of coast types: (i) areas where the water exchange is regulated by tidal effects; (ii) open coastal areas where the water exchange is regulated by coastal currents; and (iii) semi-enclosed archipelago coasts. The coastal model gives the fluxes to and from the following four abiotic compartments: surface water, deep water, ET areas (i.e., areas where fine sediment erosion and transport processes dominate the bottom dynamic conditions and resuspension appears) and A-areas (i.e., areas of continuous fine sediment accumulation). Criteria to define the boundaries for the given coastal area towards the sea, and to define whether a coastal area is open or closed are given in operational terms. The model is simple to apply since all driving variables may be readily accessed from maps and standard monitoring programs. The driving variables are: latitude, catchment area, mean annual precipitation, fallout and month of fallout and parameters expressing coastal size and form as determined from, e.g., digitized bathymetric maps using a GIS program. Selected results: the predictions of radionuclide concentrations in water and fish largely depend on two factors, the concentration in the sea outside the given

Marine biogeochemistry of radionuclides

International Nuclear Information System (INIS)

Fowler, S.W.

1997-01-01

Radionuclides entering the ocean from runoff, fallout, or deliberate release rapidly become involved in marine biogeochemical cycles. Sources, sinks and transport of radionuclides and analogue elements are discussed with emphasis placed on how these elements interact with marine organisms. Water, food and sediments are the source terms from which marine biota acquire radionuclides. Uptake from water occurs by surface adsorption, absorption across body surfaces, or a combination of both. Radionuclides ingested with food are either assimilated into tissue or excreted. The relative importance of the food and water pathway in uptake varies with the radionuclide and the conditions under which exposure occurs. Evidence suggests that, compared to the water and food pathways, bioavailability of sediment-bound radionuclides is low. Bioaccumulation processes are controlled by many environmental and intrinsic factors including exposure time, physical-chemical form of the radionuclide, salinity, temperature, competitive effects with other elements, organism size, physiology, life cycle and feeding habits. Once accumulated, radionuclides are transported actively by vertical and horizontal movements of organisms and passively by release of biogenic products, e.g., soluble excreta, feces, molts and eggs. Through feeding activities, particles containing radionuclides are ''packaged'' into larger aggregates which are redistributed upon release. Most radionuclides are not irreversibly bound to such particles but are remineralized as they sink and/or decompose. In the pelagic zones, sinking aggregates can further scavenge particle-reactive elements thus removing them from the surface layers and transporting them to depth. Evidence from both radiotracer experiments and in situ sediment trap studies is presented which illustrates the importance of biological scavenging in controlling the distribution of radionuclides in the water column. (author)

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, J.; Beresford, N. A.; Beaugelin-Seiller, K.; Bezhenar, R.; Brown, J.; Cheng, J. -J.; Ćujić, M.; Dragović, S.; Duffa, C.; Fiévet, B.; Hosseini, A.; Jung, K. T.; Kamboj, S.; Keum, D. -K.; Kryshev, A.; LePoire, D.; Maderich, V.; Min, B. -I.; Periáñez, R.; Sazykina, T.; Suh, K. -S.; Yu, C.; Wang, C.; Heling, R.

2016-03-01

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of 90Sr, 131I and 137Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.

Assessment of radionuclide contents in food in Hong Kong

International Nuclear Information System (INIS)

Yu, K.N.; Mao, S.Y.

1999-01-01

Baseline values of concentrations of the natural radionuclides ( 238 U, 226 Ra, 228 Ra/ 232 Th, 210 Pb) and artificial radionuclides ( 137 Cs, 60 Co) in food and drinks (tap water, milk, and water-based drinks) were determined by gamma spectroscopy. All food and drinks were found to contain detectable 40 K contents: 0.1 to 160 Bq Kg -1 for food and 0.006 to 61 Bq L -1 for drinks. Most of the other natural radionuclides in solid food were found to have contents below the minimum detectable activities (MDA). More samples in the leafy vegetable, tomato, carrot and potato categories contained detectable amounts of 228 Ra than the meat, cereal, and fish categories, with concentrations up to 1.2 Bq kg -1 for the former categories and 0.35 Bq kg -1 for the latter categories. The 238 U and 226 Ra radionuclides were detectable in most of the water-based drink samples, and the 228 Ra and 210 Pb radionuclides were detectable in fewer water-based drink samples. The 137 Cs contents in solid food were detectable in most of the solid food samples (reaching 0.59 Bq kg -1 ), but in drinks the 137 Cs contents were very low and normally lower than the MDA values. Nearly all the 60 Co contents in food and drinks were below the MDA values and their contents were below those of 137 Cs

Assessment of radionuclide concentration in three crustaceans species of the bay of Bengal; Mesure de la concentration de radionucleides dans trois especes de crustaces du golfe du Bengale

Energy Technology Data Exchange (ETDEWEB)

Hasan, C.K.; Zafar, M. [Chittagong Univ., Institute of Marine Sciences (Bangladesh); Chowdhury, M.I.; Kamal, M. [Radioactivity Testing and Monitoring Laboratory, Bangladesh Atomic Energy Commission, Chittagong (Bangladesh)

2006-10-15

The natural ({sup 226}Ra, {sup 228}Th, {sup 232}Th and {sup 40}K) and anthropogenic ({sup 137}Cs) radionuclides concentrations in three crustaceans species (Penaeus monodon, Metapenaeus monoceros and Panulirus versicolor), collected from the bay of Bengal, were determined with an aim of assessing any internal radiation hazard due to consumption of the shell fishes and establishing a database for radioactivity levels of the species. Very low level of radioactivity was observed in all the species. The average activity of {sup 226}Ra observed in P. monodon was 1.21 {+-} 0.27 Bq kg{sup -1} fw; in M. monoceros was 0.70 {+-}0.08 Bq kg{sup -1} fw, and in Panulirus versicolor was 1.04 {+-} 0.09 Bq kg{sup -1} fw. The activity of {sup 232}Th observed in these species was 1.30 {+-} 0.37, 0.76 {+-} 0.34 and 1.32 {+-} 0.70 Bq kg{sup -1} fw, and {sup 228}Th was 0.55 {+-} 0.26, 0.31 {+-} 0.14 and 0.74 {+-} 0.22 Bq kg{sup -1} fw, respectively. The average activity of {sup 40}K observed in these species was 12.56 {+-} 1.18, 6.38 {+-}1.02 and 10.07 {+-} 1.52 Bq kg{sup -1} fw, respectively. The activity of radiocaesium ({sup 137}Cs) was below detection limit. The results indicate that the natural and artificial radionuclides observed in three crustaceans species are safe for human health. A significant relationship was observed between {sup 226}Ra and {sup 232}Th in both the P. monodon (r = 0.839, p {<=} 0.05, df = 4) and the Panulirus versicolor (r = 0.906, p {<=} 0.05, df = 4). (authors)

Enrichment of naturally occurring radionuclides and trace elements in Yatagan and Yenikoy coal-fired thermal power plants, Turkey.

Science.gov (United States)

Ozden, Banu; Guler, Erkan; Vaasma, Taavi; Horvath, Maria; Kiisk, Madis; Kovacs, Tibor

2018-08-01

Coal, residues and waste produced by the combustion of the coal contain naturally occurring radionuclides such as 238 U, 226 Ra, 210 Pb, 232 Th and 40 K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of naturally occurring radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210 Pb and 210 Po concentration varied between 186 ± 20-1153 ± 44 Bq kg -1 , and 56 ± 5-1174 ± 45 Bq kg -1 , respectively. The highest 210 Pb and 210 Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg -1 and 1174 ± 45 Bq kg -1 , respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p ash sample analysis showed an increase activity concentration and enrichment factors towards the

Radionuclides in peat bogs and energy peat

International Nuclear Information System (INIS)

Helariutta, K.; Rantavaara, A.; Lehtovaara, J.

2000-06-01

The study was aimed at improving the general view on radionuclides contents in energy peat produced in Finland. The annual harvest of fuel peat in 1994 was studied extensively. Also thirteen peat bogs used for peat production and one bog in natural condition were analysed for vertical distributions of several radionuclides. These distributions demonstrate the future change in radioactivity of energy peat. Both natural nuclides emitting gamma radiation ( 238 U, 235 U, 232 Th, 226 Ra, 40 K) and radiocaesium ( 137 Cs, 134 Cs) origin in fallout from a nuclear power plant accident (1986) and in atmospheric nuclear weapon tests were analysed. The beta and alpha active natural nuclides of lead and polonium ( 210 Pb, 210 Po) were determined on a set of peat samples. These nuclides potentially contribute to radiation exposure through inhalation when partially released to atmosphere during combustion of peat. The activity concentrations of natural radionuclides often increased towards the deepest peat bog layers whereas the radioactive caesium deposited from atmosphere was missing in the deep layers. In undisturbed surface layers of a natural bog and peat production bogs the contents of 210 Pb and 210 Po exceeded those of the deeper peat layers. The nuclides of the uranium series in the samples were generally not in radioactive equilibrium, as different environmental processes change their activity ratios in peat. Radiation exposure from handling and utilisation of peat ash was estimated with activity indices derived from the data for energy peat harvested in 1994. Intervention doses were exceeded in a minor selection of samples due to 137 Cs, whereas natural radionuclides contributed very little to the doses. (orig.)

Distribution of natural radionuclides on coats of Bushehr, Persian Gulf, Iran

International Nuclear Information System (INIS)

Abdi, M. R.; Faghihian, H.; Kamali, M.; Mostajaboddavati, M.; Hasanzadeh, A.

2006-01-01

:A reconnaissance study has been made on the distribution of 2 38U , 2 32T h, 4 0K , 1 37C s and geochemical features in soil and sediment samples at various locations on the coast of Bushehr in the Persian Gulf. In this study a gamma-ray spectrometer based on a High Purity Germanium detector and a PC based MCA and X-ray fluorescence (XRF) method were used. Estimation of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The Activity concentration (A), the equivalent radium (R eq ), and the external hazard index (H ex ) which resulted from the natural radionuclides in soil and sediment are also calculated. The base-line data of radionuclides and heavy metals in view of the commissioning of nuclear and non-nuclear industries for the coast of Bushehr, which does not yet exist, was obtained. Activity concentration levels due to radionuclides were measured in 50 soil and sediment samples collected from this region. The measurement was performed with respect to their gamma radioactivity for a counting time of 24 hour intervals. From the accumulated spectra, activity concentration were determined for 4 0K (range from 108 to 520 Bq Kg -1 ), 1 37 Cs (from 6 to 40 Bq Kg 1 ), 2 38U (from 12 to 75 Bq Kg -1 ) and 2 32T h (from 8 to 33 Bq Kg -1 ) with the lowest limit detection (LLD) of, respectively, 68, 3.2, 4.3 and 4.3 Bq Kg -1 . The dose rate from ambient air at the soil ranges was between 14 to 44 nGy h -1 with an average of 30.56±7.86 nGy h -1

Measurement of activity concentrations for "1"3"7Cs and "4"0K in edible wild mushrooms collected from Mangshi, Yunnan province and evaluation of dose to adults

International Nuclear Information System (INIS)

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

2014-01-01

Objective: To determine the activity concentration of radionuclides for "1"3"7Cs and "4"0K in edible wild mushrooms, and to evaluate the extent of radioactive contamination and ingestion doses to adults from consumption of these wild mushrooms. Methods: A total of 33 samples for 18 edible wild mushroom species were collected from natural forest Mangshi, Yunnan province. The activity concentrations of "1"3"7Cs and "4"0K were analyzed by using high-purity germanium (HPGe) gamma spectrometry. Results: Except for one sample that was below the MDA, "1"3"7Cs artificial radionuclides were detected in other 32 samples, with activity concentration of "1"3"7Cs in the range of 0.45-339.58 Bq/kg (dry weight) and an average of 25.47 Bq/kg (dry weight). In regards to "4"0K in edible mushrooms, all species presented the activity concentrations for this radionuclide and the levels varied from 453.4 to 1882.6 Bq/kg (dry weight), with an average of 815.1 Bq/kg (dry weight). After species of mushroom with only one sample were eliminated, there was significant difference for "1"3"7Cs(F = 21.13, P < 0.05) among 6 species of mushroom named Gomphus floccosus (Schw.) Sing., Boletus edulis bull, Boletus edulis bull, Tylopllus bolloul (Peck) Sing., Lentinus edodes (Berk.) Sing. and Boletus brunneissimus W.F.Chin, but without significant difference for "4"0K. Conclusions: These 6 different mushroom species have different capacity to retain radionuclides of "1"3"7Cs in soil. These wild mushrooms, such as Gomphus floccosus (Schw.) Sing. and Lentinus edodes (Berk.) Sing. have large affinity ability for radionuclides"1"3"7Cs. The effective dose to adults attributable to consuming these kinds of mushrooms is small and below the level that could cause harm. (authors)

Radionuclides in macro algae at Monaco following the Chernobyl accident

International Nuclear Information System (INIS)

Holm, E.; Ballestra, S.; Lopez, J.J.; Bulos, A.; Whitehead, N.E.; Barci-Funel, G.; Ardisson, G.

1994-01-01

Samples of macro algae, Codmium tomentosum (green), Corallina mediterranea (red), Sphaerococcus coronopifolius (red) and Dictyota dichotoma (brown), were collected off Monaco during 1984 and 1988 and analysed for gamma-emitting radionuclides and transuranium elements. Due to the Chernobyl accident, increased radioactivity in the atmosphere at Monaco was recorded on 30 April 1986 with maximal activity concentrations on 2-3 May. The maximal activity concentrations in sea water occurred on 5-6 May and in the algae on 11 May. The decrease of activity concentrations can be described after May 11 as a single exponential relationship, where elimination rates for different radionuclides and different species specific to the environment can be calculated. The elimination rates thus observed correspond to mean residence times between 70 and 370 days corrected for physical decay. The concentration factors were also estimated and the highest values were found for 131 I, 129 Te m , and 110 Ag m and lowest for radiocesium and 140 Ba. The red algae Sphaerococcus coronopifoius showed generally higher concentration factors than green and brown algae. Regarding transuranium elements, a theoretical contribution from the Chernobyl accident can be made but only 242 Cm was detected in the algae above previous levels before the accident, due to the relatively small fallout of transuranics. (author) 23 refs.; 9 figs.; 4 tabs

Classification and Reevaluation on Radionuclide and Activity of Contaminated Soil(I)

Energy Technology Data Exchange (ETDEWEB)

Kang, Il Sik; Shon, J. S.; Kim, K. J.; Kim, T. K.; Hong, D. S.; Lee, B. C.; Cho, H. S.; Je, W. G

2006-03-15

Radioactive wastes generated during the decommissioning process and contaminated soils were transported and have been stored at the waste storage facility. The radioactivity in the wastes has been decayed a lot. The radionuclide and the activity concentration of stored soil wastes were reevaluated. And using the reevaluation results, the soil wastes were classified as either a regulatory clearance wastes or a radioactive waste. The storage space can be secured by storing regulatory clearance wastes in the extra storage facility and self disposing them. Also, the objective is to protect the environment from contamination by observing the related nuclear regulation and managing the radioactive wastes. Through the reevaluation of radioactivity and classification of contaminated soils, the unnecessary decontamination of uncontaminated soil was prevented. It allowed us to save the cost for decontamination and disposal, also we could secure the pretreatment process techniques such as how to sample and analyze the nuclide.

Assessment of natural radionuclides concentration from 238U and 232Th series in Virginia and Burley varieties of Nicotiana tabacum L

International Nuclear Information System (INIS)

Silva, Carolina Fernanda da

2015-01-01

Brazil is the largest exporter and second largest producer of tobacco worldwide, according to the crop production of 2013/2014. The tobacco plant (Nicotiana tabacum L.) is used to manufacture all derivatives and the chemical composition of the resulting tobacco products varies with the type of tobacco leaves, how they are grown, the region where they are cultivated, the characteristics of preparation (compression, filter and paper) and the temperature variations resulting from the incomplete combustion of tobacco. Tobacco products are extensively used throughout the world, and the most consumed are cigarettes, cigars and narghile. The damaging effects that these products cause to human health are discussed globally, and many surveys are performed with the aim of relating the use of these products with various illnesses. There is a lack of information about the radiological characterization of the tobacco plant both in international and Brazilian literature. The objective of this study was to determine the concentration of radionuclides 238 U, 234 U, 230 Th, 22 '6Ra, 210 Pb and 210 Po, members from the 238 U decay series, and the radionuclides 232 Th and 228 Ra members of the 232 Th decay series in the varieties Burley and Virginia, which are the most cultivated in Brazil. Plants from these varieties were cultivated in pots with organic substrate and fertilizer and also acquired from the producers and analyzed by alpha spectrometry for U and Th isotopes and 210 Po determination, and gross alpha and beta counting, 228 Ra, 226 Ra and 210 Pb determination. The whole plant, from both places, was analyzed; root, stem, leaves, as well as the organic substrate, the fertilizers, and the soil. The results for U and Th isotopes presented values below the detection limits of the methods to the leaves and stems of all plants analyzed, with measurable results only in roots, soil, and substrate. The radionuclides 226 Ra, 228 Ra, 210 Pb, and 210 Po, were determined in most

On the behaviour of artificial radionuclides at the Baltic sea coastal zone

International Nuclear Information System (INIS)

Styro, D.B.; Astrauskene, N.P.; Kadzhene, G.I.; Lukinskene, M.V.

1988-01-01

The measured results of the 137 Cs, 90 Sr and 144 Ce radionuclide concentrations near the settlement of Juodkrante at the Baltic Sea coast have been considered. The instability of the mean values of the radionuclide concentrations, especially that of strontium-90, has been determined. A certain increase of the radionuclide concentration near the sea coast as compared to that in the open sea has been noted, as well as the influence of the stormy weather on the absolute values of the radionuclide concentration at the coastal zone. 5 refs.; 3 figs.; 1 tab

Method to determine the activity concentration and total activity of radioactive waste; Metodo para determinar la concentracion de actividad y actividad total de desechos radiactivos

Energy Technology Data Exchange (ETDEWEB)

Angeles C, A

2001-02-15

A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients.

New ways enhancing the vital activity of plants in order to increase crop yields and to suppress radionuclide accumulation

International Nuclear Information System (INIS)

Goncharova, N. V; Zebrakova, I. V.; Matsko, V. P.; Kislushko, P. M.

1994-01-01

After Chernobyl nuclear accident it has become very important to seek new ways of enhancing the vital activity of plants in order to increase crop yields and to suppress radionuclide accumulation. It is found that by optimizing the vital activity processes in plants, is possible to reduce radionuclide uptake. A great number of biologically active compounds have been tested, which increased the disease resistance of plants and simultaneously activated the physiological and biochemical processes that control the transport of micro- and macroelements (radionuclide included) and their 'soil-root-stem-leaf' redistribution. (author)

Geochemistry and radionuclide migration

International Nuclear Information System (INIS)

Isherwood, D.

1978-01-01

Theoretically, the geochemical barrier can provide a major line of defense in protecting the biosphere from the hazards of nuclear waste. The most likely processes involved are easily identified. Preliminary investigations using computer modeling techniques suggest that retardation is an effective control on radionuclide concentrations. Ion exchange reactions slow radionuclide migration and allow more time for radioactive decay and dispersion. For some radionuclides, solubility alone may limit concentrations to less than the maximum permissible now considered acceptable by the Federal Government. The effectiveness of the geochemical barrier is ultimately related to the repository site characteristics. Theory alone tells us that geochemical controls will be most efficient in an environment that provides for maximum ion exchange and the precipitation of insoluble compounds. In site selection, consideration should be given to rock barriers with high ion exchange capacity that might also act as semi-permeable membranes. Also important in evaluating the site's potential for effective geochemical controls are the oxidation potentials, pH and salinity of the groundwater

Occupational exposure to natural radionuclides due to mining activities in Ibadan, Southwestern Nigeria

International Nuclear Information System (INIS)

Ademola, J.A.; Okpalaonwuka, N.E.

2010-01-01

The activity concentrations of potassium, uranium and thorium in minerals and soil samples from a mining site in Ibadan, Southwestern Nigeria were measured using gamma ray spectroscopy method. Effective dose per annum has been calculated from the activity concentrations of dominant gamma-emitting natural radionuclides, potassium, uranium and thorium. Samples collected include minerals (beryl, quartz and feldspar), soil samples from the mining pits, heaps and undisturbed land around the mining site. The activity concentrations of 40 K, 238 U and 232 Th, respectively in Bq kg-1 in the mineral samples were as follows: 1985 ± 16, 4.8 ± 0.9 and 11.8 ± 5.8 for beryl sample, 115.1 ± 27.9, 5.0 ± 1.3 and 6.3 ± 5.0 for feldspar samples and 1421 ± 122, 40 K, 238 U and 232 Th, respectively, were 314.2 ± 5.7, 27.7 ± 2.6 and 11.5 ± 5.9 Bq kg-1 for soil samples from the pits and 278.1 ± 5.4, 21.1 ± 2.0 and 15.3 ± 7.5 Bq kg-1 for soil samples from heaps. The mean activity concentrations of soil samples from the undisturbed land around the mining site were 194.3 ± 25.2, 14.5 ± 5.1 and 13.3 ± 5.9 Bq kg-1 for 40 K, 238 U and 232 Th, respectively. The effective dose to which the miners are exposed according to exposure scenarios were calculated as 89.9 μSv y-1 for digging and handling of soil and mineral samples in the pit and 63.6 μSv y-1 for handling of soil and mineral samples at the heaps. (authors)

Distribution of artificial radionuclides in particle-size fractions of soil on fallout plumes of nuclear explosions.

Science.gov (United States)

Kabdyrakova, A M; Lukashenko, S N; Mendubaev, A T; Kunduzbayeva, A Ye; Panitskiy, A V; Larionova, N V

2018-06-01

In this paper are analyzed the artificial radionuclide distributions ( 137 Cs, 90 Sr, 241 Am, 239+240 Pu) in particle-size fractions of soils from two radioactive fallout plumes at the Semipalatinsk Test Site. These plumes were generated by a low-yield surface nuclear test and a surface non-nuclear experiment with insignificant nuclear energy release, respectively, and their lengths are approximately 3 and 0,65 km. In contrast with the great majority of similar studies performed in areas affected mainly by global fallout where adsorbing radionuclides such as Pu are mainly associated with the finest soil fractions, in this study it was observed that along both analyzed plumes the highest activity concentrations are concentrated in the coarse soil fractions. At the plume generated by the surface nuclear test, the radionuclides are concentrated mainly in the 1000-500 μm soil fraction (enrichment factor values ranging from 1.2 to 3.8), while at the plume corresponding to the surface non-nuclear test is the 500-250 μm soil fraction the enriched one by technogenic radionuclides (enrichment factor values ranging from 1.1 to 5.1). In addition, the activity concentration distributions among the different soil size fractions are similar for all radionuclides in both plumes. All the obtained data are in agreement with the hypothesis indicating that enrichment observed in the coarse fractions is caused by the presence of radioactive particles resulted from the indicated nuclear tests. Copyright © 2017 Elsevier Ltd. All rights reserved.

Geomorphological applications of environmental radionuclides

International Nuclear Information System (INIS)

Quine, T.A.; Walling, D.

1998-01-01

Geomorphologists have shown increasing interest in environmental radionuclides since pioneering studies by Ritchie and McHenry in the USA and Campbell, Longmore and Loughran in Australia. Environmental radionuclides have attracted this interest because they provide geomorphologists with the means to trace sediment movement within the landscape. They, therefore, facilitate investigation of subjects at the core of geomorphology, namely the rates and patterns of landscape change. Most attention has been focussed on the artificial radionuclide caesium-137 ( 137 Cs) but more recently potential applications of the natural radionuclides lead-210 ( 210 Pb) and beryllium-7( 7 Be) have been investigated (Walling et al., 1995; Wallbrink and Murray, 1996a, 1996b). The origin, characteristics and applications of these radionuclides are summarised. These radionuclides are of value as sediment tracers because of three important characteristics: a strong affinity for sediment; a global distribution and the possibility of measurement at low concentration. Geomorphological applications of environmental radionuclides provide unique access to detailed qualitative data concerning landscape change over a range of timescales

Radionuclide Content of Pasteurized Milk Sold in Mafikeng, South Africa

International Nuclear Information System (INIS)

Olobatoke, R.; Mathuthu, M.

2015-01-01

Many food animals which are important components of human food chain are effective collectors of radionuclides from the environment particularly contaminated forages, and therefore represent a significant pathway for the transfer of radionuclides to humans. Many important radionuclides are readily transferred to milk thus the product is considered as one of the basic food items recommended for the assessment of radionuclide exposure within a population. The current study aimed at assessing the radionuclide content of commercial milk commonly sold in South Africa in other to set a baseline data for radionuclide concentration of the products. Three popular brands of commercial milk (A, B and C) were sampled, with two samples obtained for each brand. The concentration of individual radionuclide in the milk samples, particularly "1"3"1I, "1"3"7Cs and "2"3"5U was measured by gamma spectroscopy. The results showed that brand A had the highest concentrations of "2"3"5U and "1"3"7Cs (203 and 324 mBq/l respectively) but the lowest concentration of "1"3"1I (6.4 mBq/l). The highest concentration of "1"3"1I (148 mBq/l) was detected in brand B whereas both "2"3"5U and "1"3"1I were not detected in brand C. All the values however were well below the new standard limits for individual radionuclides in milk established by the Japanese Ministry of Health, Labour and Welfare. This study indicates that the commercial milk brands assessed pose no radiation health threat to the consumers. (author)

Baseline concentrations of radionuclides and heavy metals in soils and vegetation around the DARHT facility: Construction phase (1997). Progress report

International Nuclear Information System (INIS)

Fresquez, P.R.; Haagenstad, H.T.; Naranjo, L. Jr.

1998-06-01

As part of the Department of Energy's Mitigation Action Plan for the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory (LANL), baseline concentrations of radionuclides ( 3 H, 137 Cs, 90 Sr, 238 Pu, 239,240 Pu, 241 Am, and tot U) and heavy metals (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, and Tl) in soil, sediment, and vegetation (overstory and understory) around the DARHT facility during the construction phase in 1997 were determined. Most radionuclides and heavy metals in soils, sediments, and vegetation, with the exception of 90 Sr in soils and sediments, were within upper (95%) limit background concentrations. Although the levels of 90 Sr in soils and sediments around the DARHT facility were higher than background, they were below LANL screening action levels ( -1 dry) and are of no concern

Preliminary study of radionuclide corrosion products in primary cooling water at RSG-GAS

International Nuclear Information System (INIS)

Lestari, D.E.; Pudjojanto, M.S.; Subiharto; Budi, S.

1998-01-01

Analysis of radionuclides emitting gamma rays at the primary cooling water at RSG-GAS has been carried out. The water coolant samples was performed using a low level background gamma spectrometer unit, including of high resolution of gamma detector HP-Ge Tennelec and Multichannel Analyzer (MCA) ADCAM 100 ORTEC. The result indicated Na-24 and Mn-56 radionuclides that may be as corrosion product and should studied deeply in the future. The expected activity concentration radionuclide for Mn-56 is lower than those written in the Safety Analysis Report (SAR), while for Na-24 is in agreement

The transfer of radionuclides from saltmarsh vegetation to sheep tissues and milk

Energy Technology Data Exchange (ETDEWEB)

Beresford, N.A. [Centre for Ecology and Hydrology, CEH-Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom)], E-mail: nab@ceh.ac.uk; Howard, B.J. [Centre for Ecology and Hydrology, CEH-Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Mayes, R.W.; Lamb, C.S. [Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom)

2007-11-15

Radionuclides released into the Irish Sea by the Sellafield reprocessing plant are deposited onto tide-washed pastures along the western coast of the United Kingdom. Many of these pastures are grazed by sheep or cattle. This paper describes a controlled feeding study, in which saltmarsh vegetation harvested from close to the Sellafield plant, was fed to lambs and adult female sheep for a period of 8 weeks. Activity concentrations of {sup 60}Co, {sup 95}Nb, {sup 106}Ru, {sup 134}Cs, {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu and {sup 241}Am were determined in edible tissues and transfer parameters estimated. The activity concentrations of some of the radionuclides will not have been in equilibrium with those in the diet. Nevertheless, the study was reasonably realistic in terms of agricultural management as the period of the study was similar to that for which lambs graze on the saltmarshes. A field study to determine the activity concentrations of {sup 137}Cs and {sup 239,240}Pu in the milk of ewes grazing a saltmarsh close to Sellafield is also described.

Estimation of Radionuclide Concentrations and Average Annual Committed Effective Dose due to Ingestion for the Population in the Red River Delta, Vietnam.

Science.gov (United States)

Van, Tran Thi; Bat, Luu Tam; Nhan, Dang Duc; Quang, Nguyen Hao; Cam, Bui Duy; Hung, Luu Viet

2018-02-16

Radioactivity concentrations of nuclides of the 232 Th and 238 U radioactive chains and 40 K, 90 Sr, 137 Cs, and 239+240 Pu were surveyed for raw and cooked food of the population in the Red River delta region, Vietnam, using α-, γ-spectrometry, and liquid scintillation counting techniques. The concentration of 40 K in the cooked food was the highest compared to those of other radionuclides ranging from (23 ± 5) (rice) to (347 ± 50) Bq kg -1 dw (tofu). The 210 Po concentration in the cooked food ranged from its limit of detection (LOD) of 5 mBq kg -1  dw (rice) to (4.0 ± 1.6) Bq kg -1  dw (marine bivalves). The concentrations of other nuclides of the 232 Th and 238 U chains in the food were low, ranging from LOD of 0.02 Bq kg -1  dw to (1.1 ± 0.3) Bq kg -1  dw. The activity concentrations of 90 Sr, 137 Cs, and 239+240 Pu in the food were minor compared to that of the natural radionuclides. The average annual committed effective dose to adults in the study region was estimated and it ranged from 0.24 to 0.42 mSv a -1 with an average of 0.32 mSv a -1 , out of which rice, leafy vegetable, and tofu contributed up to 16.2%, 24.4%, and 21.3%, respectively. The committed effective doses to adults due to ingestion of regular diet in the Red River delta region, Vietnam are within the range determined in other countries worldwide. This finding suggests that Vietnamese food is safe for human consumption with respect to radiation exposure.

3D modeling of effects of increased oxygenation and activity concentration in tumors treated with radionuclides and antiangiogenic drugs

Energy Technology Data Exchange (ETDEWEB)

Lagerloef, Jakob H.; Kindblom, Jon; Bernhardt, Peter [Department of Radiation Physics, Goeteborg University, Goeteborg 41345 (Sweden); Department of Oncology, Sahlgrenska University Hospital, Goeteborg 41345 (Sweden); Department of Radiation Physics, Goeteborg University, Goeteborg, Sweden and Department of Nuclear Medicine, Sahlgrenska University Hospital, Goeteborg 41345 (Sweden)

2011-08-15