| 1. |
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| 2. |
- Pham, M. K., et al.
(författare)
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A new Certified Reference Material for radionuclides in Irish sea sediment (IAEA-385)
- 2008
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Ingår i: APPLIED RADIATION AND ISOTOPES. - : Elsevier BV. - 1872-9800 .- 0969-8043. ; 66:11, s. 1711-1717
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Konferensbidrag (refereegranskat)abstract
- A new Certified Reference Material (CRM) for radionuclides in sediment (IAEA-385) is described and the results of the certification process are presented. Eleven radionuclides (K-40, Cs-137, Ra-226, Ra-228, Th-230, Th-232, U-234, U-238, Pu-238, Pu239+240 and Am-241) have been certified and information mass activities with 95% confidence intervals are given for seven other radionuclides (Sr-90, Pb-210(Po-210), U-235, Pu-239, Pu-240 and Pu-241). Results for less frequently reported radionuclides (Co-60, Tc-99, Cs-134, Eu-155, Ra-224 and Np-239) and information on some activity and mass ratios are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in sediment samples, for the development and validation of analytical methods and for training purposes. (C) 2008 IAEA. Published by Elsevier Ltd. All rights reserved.
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| 3. |
- Regev, A, et al.
(författare)
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The Human Cell Atlas
- 2017
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Ingår i: eLife. - : ELIFE SCIENCES PUBLICATIONS LTD. - 2050-084X. ; 6
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Tidskriftsartikel (refereegranskat)
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| 4. |
- Anderson, Leif G., et al.
(författare)
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The effect of the Siberian tundra on the environment of the shelf seas and the Arctic Ocean
- 1999
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Ingår i: Ambio. - 0044-7447. ; 28:3, s. 270-280
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Tidskriftsartikel (refereegranskat)abstract
- The Tundra Ecology -94 expedition investigated inflow of inorganic and organic carbon to the shelf seas by river runoff, and its transformation by biochemical processes in seawater and sediment. In addition, anthropogenic radionuclides, 137Cs, 90Sr, and 239,240Pu, were studied in water and sediments. The distribution of dissolved inorganic carbon indicates that the majority of the Ob and Yenisey discharges flow into the Laptev Sea before entering the central Arctic Ocean. The sediment study shows that there is a marked difference in benthic oxygen uptake, efflux of dissolved inorganic carbon and nutrients between localities. 137Cs activity from the Chernobyl accident is 30% in the Barents, Kara, and Laptev Seas. 137Cs increased from 5-8 Bq m-3 in Barents Sea, 5-13 Bq m-3 in the Kara Sea to 8-15 Bq m-3 in the Laptev Sea, but with locally low concentrations at the river mouths. Corresponding values for 90Sr were 2.5, 3, and 4 Bq m-3, respectively.
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| 5. |
- Holm, Elis, et al.
(författare)
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Five Decades of Nordic Radioecology
- 2006
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Ingår i: Young Rad Seminar. - 9788778932242 ; , s. 9-9
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 6. |
- Holm, Elis, et al.
(författare)
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Global fallout of curium
- 1978
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 273:5660, s. 289-290
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Tidskriftsartikel (refereegranskat)abstract
- THE search for 242mAm (t1/2=152 yr) in environmental samples has involved detection of its daughter 242Cm (t 1/2=163 d) (refs 1-3). These samples were contaminated by transuranium nuclides either from a nuclear fuel reprocessing plant or from a thermonuclear test fallout. A logical consequence was then to analyse global fallout-contaminated samples for 242Cm and 244Cm to establish the present distribution and global contamination of our environment by these transuranium elements. We have chosen the lichen Cladonia alpestris, which is an excellent bioindicator for atmospheric fallout and we present the results here. The samples have been stored in the laboratory for 5-16 yr. Thus, 242mAm and 242Cm were in sequelar radioactive equilibrium. The 242Cm present in the aged samples therefore represents the 242mAm present in the fallout. The results indicate a 242mAm/239+240Pu activity ratio of about 0.003% in global fallout.
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| 7. |
- Maccubbin, D., et al.
(författare)
-
Lipid-modifying efficacy and tolerability of extended-release niacin/laropiprant in patients with primary hypercholesterolaemia or mixed dyslipidaemia
- 2008
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Ingår i: International journal of clinical practice (Esher). - : Hindawi Limited. - 1368-5031 .- 1742-1241. ; 62:12, s. 1959-1970
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Tidskriftsartikel (refereegranskat)abstract
- Background: Improving lipids beyond low-density lipoprotein cholesterol (LDL-C) lowering with statin monotherapy may further reduce cardiovascular risk. Niacin has complementary lipid-modifying efficacy to statins and cardiovascular benefit, but is underutilised because of flushing, mediated primarily by prostaglandin D2 (PGD2). Laropiprant (LRPT), a PGD 2 receptor (DP1) antagonist that reduces niacin-induced flushing has been combined with extended-release niacin (ERN) into a fixed-dose tablet. Methods and results: Dyslipidaemic patients were randomised to ERN/LRPT 1 g (n = 800), ERN 1 g (n = 543) or placebo (n = 270) for 4 weeks. Doses were doubled (2 tablets/day, i.e. 2 g for active treatments) for 20 weeks. ERN/LRPT 2 g produced significant changes vs. placebo in LDL-C (-18.4%), high-density lipoprotein cholesterol (HDL-C, 20.0%), LDL-C:HDL-C (-31.2%), non-HDL-C (-19.8%), triglycerides (TG, -25.8%), apolipoprotein (Apo) B (-18.8%), Apo A-I (6.9%), total cholesterol (TC, -8.5%), TC:HDL-C (-23.1%) and lipoprotein(a) (-20.8%) across weeks 12-24. ERN/LRPT produced significantly less flushing than ERN during initiation (week 1) and maintenance (weeks 2-24) for all prespecified flushing end-points (incidence, intensity and discontinuation because of flushing). Except for flushing, ERN/LRPT had a safety/tolerability profile comparable with ERN. Conclusion: Extended-release niacin/LRPT 2 g produced significant, durable improvements in multiple lipid/lipoprotein parameters. The improved tolerability of ERN/LRPT supports a simplified 1 g?2 g dosing regimen of niacin, a therapy proven to reduce cardiovascular risk. © 2008 Merck & Co.
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| 8. |
- Persson, Bertil R.R., et al.
(författare)
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Radioecological modelling of Polonium-210 and Caesium-137 in lichen-reindeer-man and top predators
- 2018
-
Ingår i: Journal of Environmental Radioactivity. - : Elsevier BV. - 0265-931X .- 1879-1700. ; 186, s. 54-62
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Tidskriftsartikel (refereegranskat)abstract
- This work deals with analysis and modelling of the radionuclides 210Pb and210Po in the food-chain lichen-reindeer-man in addition to 210Po and 137Cs in top predators. By using the methods of Partial Least Square Regression (PLSR) the atmospheric deposition of 210Pb and 210Po is predicted at the sample locations. Dynamic modelling of the activity concentration with differential equations is fitted to the sample data. Reindeer lichen consumption, gastrointestinal absorption, organ distribution and elimination is derived from information in the literature. Dynamic modelling of transfer of 210Pb and 210Po to reindeer meat, liver and bone from lichen consumption, fitted well with data from Sweden and Finland from 1966 to 1971. The activity concentration of 210Pb in the skeleton in man is modelled by using the results of studying the kinetics of lead in skeleton and blood in lead-workers after end of occupational exposure. The result of modelling 210Pb and 210Po activity in skeleton matched well with concentrations of 210Pb and 210Po in teeth from reindeer-breeders and autopsy bone samples in Finland.The results of 210Po and 137Cs in different tissues of wolf, wolverine and lynx previously published, are analysed with multivariate data processing methods such as Principal Component Analysis PCA, and modelled with the method of Projection to Latent Structures, PLS, or Partial Least Square Regression PLSR.
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| 9. |
- Persson, B. R.R., et al.
(författare)
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Radiolead (210Pb) and stable lead in the lichen Cladonia alpestris
- 1974
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Ingår i: Oikos. - : JSTOR. - 0030-1299. ; 25:2, s. 140-147
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Tidskriftsartikel (refereegranskat)abstract
- Lichens of the genus Cladonia, mainly C. alpestris, collected during 1882-1972 were analyzed for stable lead and 210Pb. The specific activity of 210Pb (210Pb/Pb ratio) indicates a constant value of about 2 mCi/kg up to 1940, and then decreased to 0.6 mCi/kg during 1950-1960. As the average annual 210Pb deposition is relatively constant, the decrease in the 210Pb/Pb ratio after 1940 indicates an increased deposition of stable lead after 1940. A single exponential variation of the 210Pb/Pb ratio, in respect to latitude, was found in lichens collected in 1964. Values for 210Pb and stable lead in C. alpestris, collected in central Sweden during 1961-1972, appear to be relatively constant and the average area content of 210Pb and stable lead in lichen carpets was 15 ± 2 nCi/m2 and 25 ± 5 mg/m2 respectively. The pattern of vertical distribution was converted to a model for the translocation of lead in lichens, which included the diffusion principle. The diffusion coefficient for lead in the top layer of the lichen carpet was estimated to be about (0.2 ± 0.1) x 10-6 cm2 x s-1.
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| 10. |
- Al-Qaradawi, Ilham, et al.
(författare)
-
Radioactivity levels in the marine environment along the Exclusive Economic Zone (EEZ) of Qatar.
- 2015
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 1879-3363 .- 0025-326X. ; 90:1-2, s. 323-329
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Tidskriftsartikel (refereegranskat)abstract
- A study on (137)Cs, (40)K, (226)Ra, (228)Ra, and (238)U was carried out along the EEZ of Qatar. Results serve as the first ever baseline data. The level of (137)Cs (mean value 1.6±0.4Bqm(-3)) in water filters was found to be in the same order of magnitude as reported by others in worldwide marine radioactivity studies. Results are also in agreement with values reported from other Gulf regions. The computed values of sediment-water distribution coefficients Kd, are lower than the values given by IAEA. Measurements were carried out for bottom sediments, biota samples like fish, oyster, sponge, seashell, mangrove, crab, shrimp, starfish, dugong and algae. The 'concentration factors' reported for biota samples are below the levels published by IAEA and cause no significant impact on human health for seafood consumers in Qatar.
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| 11. |
- Chamizo, E., et al.
(författare)
-
Insights into the Pu isotopic composition (239Pu, 240Pu, and 241Pu) and 236U in marshland samples from Madagascar
- 2020
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 740
-
Tidskriftsartikel (refereegranskat)abstract
- This work provides new insights into the presence of 239Pu, 240Pu, 241Pu, and 236U in the Southern Hemisphere through the study of peat bog cores from marshlands in Madagascar (19°S). 210Pb, 238Pu and 239+240Pu activities were characterized by alpha spectrometry in previous studies. Here, Pu from alpha-spectrometry discs corresponding to 10 peat-bog cores (85 samples) was reassessed for the aim of completing its isotopic composition (239Pu, 240Pu, and 241Pu) by Accelerator Mass Spectrometry. In addition, 236U was studied in a single core exhibiting unusually low 240Pu/239Pu ratios. Integrated 240Pu/239Pu atom ratios in the single cores ranged above and below the (0–30°S) fallout average ratio, 0.173 ± 0.027, from 0.126 ± 0.003 to 0.206 ± 0.002, without a regional pattern, thereby demonstrating the heterogeneous distribution of the 239Pu and 240Pu signal. However, such a variability was not observed for 241Pu/239Pu, ranging from (6 ± 1) · 10−4 to (11 ± 1) · 10−4 and consistently below the (0–30°S) fallout ratio of (9.7 ± 0.3) · 10−4 (2012). The integrated 236U/239Pu atom ratio in the studied core, 0.147 ± 0.005, was also significantly lower than the values reported for the global fallout in the Northern Hemisphere, in the 0.20–0.23 range. Our results point out to stratospheric fallout as the main source of both 236U and 241Pu at the studied site, whereas 239Pu and 240Pu signals show the influence of tropospheric fallout from the low-yield tests conducted in Australia (1952–1958) by United Kingdom and in French Polynesia (1966–1975) by France despite the long relative distances (i.e. about 15,000 and 8500 km). It was also demonstrated that a representative number of samples is necessary in order to assess Pu contamination and its various origins in a specific region in the Southern Hemisphere due to the heterogeneous distribution, and results based on single sample analysis should be interpreted with caution. © 2020 Elsevier B.V.
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| 12. |
- Gjelsvik, Runhild, et al.
(författare)
-
Polonium-210 and Caesium-137 in lynx (Lynx lynx), wolverine (Gulo gulo) and wolves (Canis lupus).
- 2014
-
Ingår i: Journal of Environmental Radioactivity. - : Elsevier BV. - 1879-1700 .- 0265-931X. ; 138:May 5, s. 402-409
-
Tidskriftsartikel (refereegranskat)abstract
- Wolves, lynx and wolverines are on the top of the food-chain in northern Scandinavia and Finland. (210)Po and (137)Cs have been analysed in samples of liver, kidney and muscle from 28 wolves from Sweden. In addition blood samples were taken from 27 wolves. In 9 of the wolves, samples of muscle, liver and blood were analysed for (210)Po. Samples of liver and muscle were collected from 16 lynx and 16 wolverines from Norway. The liver samples were analysed for (210)Po and (137)Cs. Only (137)Cs analyses were carried out for the muscle samples. The wolves were collected during the winter 2010 and 2011, while the samples for lynx and wolverines were all from 2011. The activity concentrations of (210)Po in wolves were higher for liver (range 20-523 Bq kg(-1) d.w.) and kidney (range 24-942 Bq kg(-1) d.w.) than muscle (range 1-43 Bq kg(-1) d.w.) and blood (range 2-54 Bq kg(-1) d.w.). Activity ratios, (210)Po/(210)Pb, in wolf samples of muscle, liver and blood were in the ranges 2-77, 9-56 and 2-54. Using a wet weight ratio of 3.8 the maximal absorbed dose from (210)Po to wolf liver was estimated to 3500 μGy per year. Compared to wolf, the ranges of (210)Po in liver samples were lower in lynx (range 22-211 Bq kg(-1) d.w.) and wolverine (range16-160 Bq kg(-1) d.w.). Concentration of (137)Cs in wolf samples of muscle, liver, kidney and blood were in the ranges 70-8410 Bq kg(-1) d.w., 36-4050 Bq kg(-1) d.w., 31-3453 Bq kg(-1) d.w. and 4-959 Bq kg(-1) d.w., respectively. (137)Cs in lynx muscle and liver samples were in the ranges 44-13393 Bq kg(-1) d.w. and 125-10260 Bq kg(-1) d.w. The corresponding values for (137)Cs in wolverine were 22-3405 Bq kg(-1) d.w. for liver and 53-4780 Bq kg(-1) d.w. for muscle. The maximal absorbed dose from (137)Cs to lynx was estimated to 3000 μGy per year.
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| 13. |
- Gomez-Guzman, J. M., et al.
(författare)
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Analysis of I-129 in lichens by accelerator mass spectrometry through a microwave-based sample preparation method
- 2010
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X. ; 268:7-8, s. 1171-1174
-
Konferensbidrag (refereegranskat)abstract
- The presence of I-129 in the environment has been strongly influenced by the artificial nuclear emissions since the beginning of the nuclear era in the mid 20th century. In order to know more about the different sources and their relative impact in different zones, it is necessary to complete the amount of measurements of this radionuclide in environmental samples. In this work, I-129 has been determined in lichen samples (Cladonia alpestris) from Rogen Lake in Central Sweden. A method based on microwave digestion was developed for these measurements in order to improve speed and reduce contamination. Based on this method, I-129 concentrations in some lichen samples from Lake Rogen (Sweden) have been measured, showing the impact of the Chernobyl accident and nuclear fuel reprocessing plants. (C) 2009 Elsevier B.V. All rights reserved.
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| 14. |
- Holm, Elis, et al.
(författare)
-
Fallout of 238 Pu over Madagascar following the SNAP 9 A satellite failure.
- 2015
-
Ingår i: Environmental Radiochemical Analysis V. P. Warwick (ed.). - UK : Royal Society of Chemistry, UK. - 9781782621553 ; :12, s. 44-49
-
Bokkapitel (refereegranskat)abstract
- After the SNAP 9A satellite accident in 1964, the dispersion of Pu was investigated as a function of latitude North and South. It was obvious that most of the fallout of 238Pu was on the southern hemisphere. However no data from Madagascar, where the accident happened, were reported. This paper describes the analysis of peat bog samples for Pu-isotopes by alpha spectrometry after radiochemical separation. To investigate especially the presence of 239Pu, selected samples were analyzed for 239Pu and 240Pu using mass spectrometric analyses, AMS.
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| 15. |
- Jimenez-Ramos, M. C., et al.
(författare)
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A comparison of two micro-beam X-ray emission techniques for actinide elemental distribution in microscopic particles originating from the hydrogen bombs involved in the Palomares (Spain) and Thule (Greenland) accidents
- 2010
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Ingår i: Spectrochimica Acta, Part B: Atomic Spectroscopy. - : Elsevier BV. - 0584-8547. ; 65:9-10, s. 823-829
-
Tidskriftsartikel (refereegranskat)abstract
- In order to validate and to gain confidence in two micro-beam techniques: particle induced X-ray emission with nuclear microprobe technique (mu-PIXE) and synchrotron radiation induced X-ray fluorescence in a confocal alignment (confocal SR mu-XRF) for characterization of microscopic particles containing actinide elements (mixed plutonium and uranium) a comparative study has been performed. Inter-comparison of the two techniques is essential as the X-ray production cross-sections for U and Pu are different for protons and photons and not well defined in the open literature, especially for Pu. The particles studied consisted of nuclear weapons material, and originate either in the so called Palomares accident in Spain, 1966 or in the Thule accident in Greenland, 1968. In the determination of the average Pu/U mass ratios (not corrected by self-absorption) in the analysed microscopic particles the results from both techniques show a very good agreement. In addition, the suitability of both techniques for the analysis with good resolution (down to a few mu m) of the Pu/U distribution within the particles has been proved. The set of results obtained through both techniques has allowed gaining important information concerning the characterization of the remaining fissile material in the areas affected by the aircraft accidents. This type of information is essential for long-term impact assessments of contaminated sites. (C) 2010 Elsevier B.V. All rights reserved.
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| 16. |
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| 17. |
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| 18. |
- Persson, Bertil R, et al.
(författare)
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(7)Be, (210)Pb, and (210)Po in the surface air from the Arctic to Antarctica.
- 2014
-
Ingår i: Journal of environmental radioactivity. - : Elsevier BV. - 1879-1700 .- 0265-931X. ; 138, s. 364-74
-
Tidskriftsartikel (refereegranskat)abstract
- In the present study we have investigated the activity concentrations of (210)Pb, (210)Po as well as (7)Be in surface air of the North and South Atlantic (1988-1989), the Arctic Ocean (1991), and along the coastline of Siberia (1994) during succeeding expeditions in the Swedish Polar Research program. During the cruises in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average airconcentrations of (7)Be was 0.6±0.4mBq/m(3), (210)Pb 40±4μBq/m(3) and (210)Po-38±10μBq/m(3). During the Swedish-Russian Tundra Ecology-94 expedition along the Siberian coastline the average air concentrations of (7)Be and (210)Pb measured during May-July were 11±3, and 2.4±0.4mBq/m(3), and during July-September they were 7.2±2 and 2.7±1.1mBq/m(3) respectively. The results from measurements of the activity concentration of (210)Pb in the air over the Arctic Ocean vary between 75 and 176μBq/m(3). Inthe air close to land masses, however, the activity concentration of (210)Pb in the air increases to 269-2712μBq/m(3). The activity concentration of (7)Be in the South Atlantic during the cruise down to Antarctica varied between 1.3 and 1.7 with an average of 1.5±0.8mBq/m(3). The activity concentration of (210)Pb in the South Atlantic down to Antarctica varied between 6 and 14μBq/m(3). At the Equator the activity concentration recorded in November 1988 was 630μBq/m(3) and in April 1989 it was 260μBq/m(3). The average activity concentration of (210)Pb during the route Gothenburg-Montevideo in 1988 was 290 and on the return Montevideo-Gothenburg it was 230μBq/m(3). The activity concentration of (210)Po in the South Atlantic down to Antarctica varied between 15 and 58μBq/m(3). At the Equator the activity concentration in November 1988 was 170 and in April 1989 it was 70μBq/m(3). The average activity concentration of (210)Po during the route Gothenburg-Montevideo in 1988 was 63 and on the return Montevideo-Gothenburg it was 60μBq/m(3). The average of the activity concentrations in the Antarctic air of (210)Pb was 27±10μBq/m(3) and of (210)Po it was 12±7μBq/m(3). All our results were compiled together with other published data, and the global latitudinal distribution of (210)Pb was converted to total annual deposition (Bq/m(2)/a) and fitted to a 4th degree polynomial. By using the global latitudinal distribution of (210)Po/(210)Pb-activity ratio from our own results the global latitudinal distribution of (210)Po annual deposition was derived.
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| 19. |
- Persson, Bertil R, et al.
(författare)
-
II INTERNATIONAL CONFERENCE ONRADIOECOLOGICAL CONCENTRATION PROCESSES : II INTERNATIONAL CONFERENCE 50 years later
- 2016
-
Bok (refereegranskat)abstract
- From the 6th to the 9th of November 2016, in the meeting hall of Centro Nacional de Aceleradores(University of Seville, Seville, Spain) took place the “II International Conference onRadioecological Concentration Processes (50 years later)” under the joint organization of theUniversities of Seville (Spain) and Gothenburg (Sweden). With this event, the organization try tocommemorate the fifty years anniversary of the first Radioecological Concentration ProcessesConference hold in Stockholm, which is recognized as an extremely important event whichcontributed to the birth of the modern radioecology: In the pioneer 1966 conference, more than 100communications were presented and a good number of participants played afterwards an essentialrole in the development and growing of the radioecology as scientific discipline.The first conference had as a main motivation the dissemination of the radioecological studiesappearing at that time associated to the nuclear weapon tests performed by USA and the formerUSSR at the end of the 1950s or beginning of the 1960s. Since then, a lot of anthropogenicemissions of radioactivity (provoked or accidental) have occurred, being remarkable at the dates ofthis II edition the 30 years passed since the Chernobyl accident and the 5 years passed from theFukushima accident. In addition, the emergence of new analytical techniques has made possible toextend the radioecological studies to new radionuclides and environmental compartments.With this II edition of the Conference, the promotors have tried to obtain information about theactual status of the radioecology over the world, to evaluate the advances reached during the lastyears and to plan the development of some priority research lines to be followed along the first halfof the XXI century. Just thinking in the future of the radioecology, special efforts were devoted tostimulate the active participation, through presentation of communications, of young researchers.
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| 20. |
- Persson, Bertil R, et al.
(författare)
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Polonium-210 and lead-210 in the terrestrial environment: A historical review.
- 2011
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Ingår i: Journal of Environmental Radioactivity. - : Elsevier BV. - 1879-1700 .- 0265-931X. ; 102, s. 420-429
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Tidskriftsartikel (refereegranskat)abstract
- The radionuclides (210)Po and (210)Pb widely present in the terrestrial environment are the final long-lived radionuclides in the decay of (238)U in the earth's crust. Their presence in the atmosphere is due to the decay of (222)Rn diffusing from the ground. The range of activity concentrations in ground level air for (210)Po is 0.03-0.3 Bq m(-3) and for (210)Pb 0.2-1.5 Bq m(-3). In drinking water from private wells the activity concentration of (210)Po is in the order of 7-48 mBq l(-1) and for (210)Pb around 11-40 mBq l(-1). From water works, however, the activity concentration for both (210)Po and (210)Pb is only in the order of 3 mBq l(-1). Mosses, lichens and peat have a high efficiency in capturing (210)Po and (210)Pb from atmospheric fallout and exhibit an inventory of both (210)Po and (210)Pb in the order of 0.5-5 kBq m(-2) in mosses and in lichens around 0.6 kBq m(-2). The activity concentrations in lichens lies around 250 Bq kg(-1), dry mass. Reindeer and caribou graze lichen which results in an activity concentration of (210)Po and (210)Pb of about 1-15 Bq kg(-1) in meat from these animals. The food chain lichen-reindeer or caribou, and Man constitutes a unique model for studying the uptake and retention of (210)Po and (210)Pb in humans. The effective annual dose due to (210)Po and (210)Pb in people with high consumption of reindeer/caribou meat is estimated to be around 260 and 132 μSv a(-1) respectively. In soils, (210)Po is adsorbed to clay and organic colloids and the activity concentration varies with soil type and also correlates with the amount of atmospheric precipitation. The average activity concentration levels of (210)Po in various soils are in the range of 20-240 Bq kg(-1). Plants become contaminated with radioactive nuclides both by absorption from the soil (supported Po) and by deposition of radioactive fallout on the plants directly (unsupported Po). In fresh leafy plants the level of (210)Po is particularly high as the result of the direct deposition of (222)Rn daughters from atmospheric deposition. Tobacco is a terrestrial product with high activity concentrations of (210)Po and (210)Pb. The overall average activity concentration of (210)Po is 13 ± 2 Bq kg(-1). It is rather constant over time and by geographical origin. The average median daily dietary intakes of (210)Po and (210)Pb for the adult world population was estimated to 160 mBq day(-1) and 110 mBq day(-1), corresponding to annual effective doses of 70 μSv a(-1) and 28 μSv a(-1), respectively. The dietary intakes of (210)Po and (210)Pb from vegetarian food was estimated to only 70 mBq day(-1) and 40 mBq day(-1) corresponding to annual effective doses of 30.6 μSv a(-1) and 10 μSv a(-1), respectively. Since the activity concentration of (210)Po and (210)Pb in seafood is significantly higher than in vegetarian food the effective dose to populations consuming a lot of seafood might be 5-15 fold higher.
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| 21. |
- Persson, Bertil R, et al.
(författare)
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Radioactivity Exploration from the Arctic to Antarctica. Part 5: The Tundra-94 expedition
- 2015
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Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:006, s. 1-20
-
Tidskriftsartikel (refereegranskat)abstract
- The joint Swedish-Russian “Tundra Ecology-94” expedition during 1994 used the large Russian ice-breaking research vessel R/V Akademik Fedorov a platform and went along a coastline of 3500 km-from the Kola Peninsula 10°E to Kolyuchinskaya Bay 173°E. Radioactivity in air, seawater and sediment was explored at various locations along the route. The average of 7Be activity concentration in air over the Arctic Ocean was found to be only about 0.6 mBq.m-3, in air close to the Siberian coast-line, however, it was as high as 11 mBq.m-3. The activity concentration of 210Pb in the air over the Arctic Ocean varies between 37 – 176 micro-Bq.m-3. In the air close to the Siberian coastline 71oN 84oE, however, the activity concentration of 210Pb in the air was much higher, about 2500 micro.Bq.m-3. Anthropogenic radioactivity in the Arctic originate from nuclear weapons fallout, release from nuclear fuel reprocessing plant, and from the Chernobyl accident. The minimum values of the 137Cs activity concentration water along the route of the Tundra were found in South-eastern Barents Sea: 5.3 Bq.m-3 of surface-water, and of bottom-water 6.4 Bq.m-3. Maximum values were found in the Western Laptevsea: 12.8 Bq.m-3 of surface-water, and of bottom-water 5.1 Bq.m-3. East of 150 oE the 134Cs / 137Cs ratios are less than 0.003, indicating that less than 6% of the 137Cs originated from the Chernobyl accident. 137Cs levels are reduced to values of about 1.4 Bq.m-3 in the low salinity water near the mouths of the Ob and Yenisey Rivers. The 134Cs / 137Cs activity ratio of 0.014 in the freshwater indicates that the Chernobyl component in the river systems is the same (30%) as in the marine waters west of 150 oE. In surface water the 90Sr activity concentration range from 2 to 4 Bq.m-3, Maximuim values about 3.5 Bq.m-3 were found between 100-140 oE. But east of 150 oE the values decreased to about 0.5 Bq.m-3 at 170 oE. In bottom water the 90Sr activity concentration range from 1.5 at 40 oE to maximum values about 4 Bq.m-3 between 100-120 oE. . The measured 90Sr/137Cs ratios in surface water close to a value of 0.14 over a wide range of stations from the Barents to the Laptev Seas. The 129I concentration in sea-water along the route of the Tundra expedition decrease from about 20·1011 atoms.l-1 at 40 oE, to about 1·1011 atoms.l-1 east of 160 oE. The 239+240Pu activity concentration in surface seawater decrease from about 10 mBq.m-3 to about 1 mBq.m-3 east of 160 oE. In bottom seawater it is more evenly distributed between 10-4 mBq.m-3, with minimum at 60-80 oE and maxima at 40oE and 160 oE. Measured 238Pu/239,240Pu activity ratios in the water column yield no evidence of any leakage of plutonium from dumped nuclear wastes in the Kara and Barents Seas.
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| 22. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity Exploration from the Arctic to the Antarctic
- 2016
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- This book is dedicated to professor emeritus Bengt Forkman (Nuclear Physics, Lund University) who in 1979 took the initiative to arrange an environmental radioactivity research program for the Ymer-80 expedition. He engaged his old friend Bertil Persson whom he during the 1960th inspired to university studies in Lund who just been promoted to professor of Radioecology at the Swedish University of Agricultural Sciences in Uppsala. Bertil Persson was tutor for Elis Holm at Lund University, who for his thesis was engaged in radiochemical analysis of plutonium isotopes in the environment. Elis Holm became deeply involved in management of Ymer-80 and all the following expeditions as well. We found a superior talent for the logistics in Kjell-Åke Carlsson (who was mechanical engineer at the department of radiation physics at Lund University). Without him, we would not have been able to solve all the thousands of practical issues and contacts with authorities and sponsors. He also contributed with the diaries extensive photographic and video documentation of all the expeditions. We have together compiled this book although several others were partly engaged in the various expeditions to whom we are deeply thankful for their contributions. They will appear as contributors in the separate parts of this book: 1. Ymer-80 (Bengt Forkman, Boel Forkman, Lars Ahlgren (diseased) 2. Swedarp 1988-1989 (Per Roos, Birgitta Roos) 3. Arctic Ocean 1991 4. Tundra Expedition 5. Arctic Ocean 1996 (Dan Josefsson, Mats Ericsson) Our first Arctic expedition “Ymer-80” was conducted during the period June 23 - 0ctober 6 1980, to commemorate the discovery of the Northeast Passage by Adolf Erik Nordenskiöld in 1878-1880. The vessel used for the expedition was the Swedish icebreaker, M/S Ymer. The use of such a heavy icebreaker made areas permanently covered with ice accessible to extensive scientific activity by various research teams. The aim of our radio-ecological research was to investigate present levels and sources of both natural and man-made radioactivity in the Arctic air and marine environment, and to study the pathways and distribution of these radionuclides in different compartments. Apart from caesium and plutonium isotopes, we also investigated natural radioactive elements, such as uranium and thorium in water, as well as radon and radon daughters in the air (Holm et al., 1983, Samuelsson et al., 1986). In the Arctic water samples were collected between 57°N to 82.8 °E, and enhanced levels of 137Cs was found along the Norwegian coast caused by 137Cs released from European nuclear fuel reprocessing facilities spread by the Gulf Stream along the Norwegian coast. We also found hot spot of plutonium in the Arctic Ocean. During the expedition, far out in the ice. Far out in the Arctic ice Bertil Persson received a call on short wave radio from the Chancellor of Lund University, Håkan Westling, who asked if he would accept promotion as professor in Medical radiation Physics and Head of Radiation Physics at Lund University Hospital. The answer was “Yes”, and so the exploration of environmental radioactivity proceeded. The second expedition “Swedarp” took place during Nov 1988 to Feb 1989. The research platform was the ship, M/S Stena Arctica, with air-sampling device installed on board. We started from Gothenburg (67.4oN; 12oE) with the first destination Montevideo (34.8oS; 56.2oW). From Montevideo, we continued to the Swedish permanent base “Svea” at the North shelf of Antarctica. After unloading supply and equipment for the continental research group, the ship continued to the Argentinean base “Marambio”. The expedition members were allowed to visit “Paulet Island” with the remains of the stone-hut, built by the Swedish captain Carl Anton Larsen and his crew during 1903-04, after that their vessel "Antarctic" was shattered by the ice masses in the Weddell Sea and sank. The third expedition in 1991 was to the Arctic Ocean with the Swedish icebreaker M/S Oden. The research program was focused on oceanography and geology in the western parts of the Eurasian Basin, the north west Markov Basin and parts of the Barents sea (Josefsson, 1998 , Roos et al., 1998). By using pumps of the ship, samples of surface-water, were collected and processed in 200 l vessels in our laboratory accommodated in a container on board. The forth expedition was the joint Swedish-Russian “Tundra Ecology-94” expedition during 1994 with the Russian ice-breaking research vessel R/V Akademik Fedorov a platform, along a coastline of 3500 km-from the Kola Peninsula 10°E to Kolyuchinskaya Bay 173°E. Air sampling was performed during the route along the Norwegian and North Siberian coastlines and water samples were collected from the vessels cooling water system. Continuous sampling of caesium took place with a separate pump and a pipe hanging from the rail. Finally, in 1996 we returned to the Arctic Ocean with the Swedish icebreaker M/S Oden. This expedition focused on studying the distribution of radionuclides in different water masses of the central Arctic Ocean. The expedition crossed the Barents Sea, entered the Nansen Basin at the St. Anna Trough, and continued north across the Amundsen Basin. The main part of the expedition was concentrated on the north Lomonosov Ridge and the return route passed the North Pole and went south along 10 oE towards Svalbard. Water samples from the surface and subsurface layers, as well as bottom sediments, were collected for analysis of fission products and transuranic elements in seawater and sediment.
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| 23. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity Exploration : From the Arctic to the Antarctic
- 2017
-
Bok (refereegranskat)abstract
- This book is dedicated to professor emeritus Bengt Forkman (Nuclear Physics, Lund University) who in 1979 took the initiative to arrange an environmental radioactivity research program for the Ymer-80 expedition. He engaged his old friend Bertil Persson whom he during the 1960th inspired to university studies in Lund and who 1980 has been promoted to professor of Radioecology at the Swedish University of Agricultural Sciences in Uppsala, Sweden. Bertil Persson was tutor for Elis Holm at Lund University, who for his thesis was engaged in radiochemical analysis of plutonium isotopes in the environment. Elis Holm became deeply involved in Ymer-80 and management of all the following expeditions as well. We found a superior talent for the logistics in Kjell-Åke Carlsson (who was mechanical engineer at the department of radiation physics at Lund University). Without him, we would not have been able to solve all the thousands of practical issues and contacts with authorities and sponsors. He also contributed with the diaries extensive photographic and video documentation of all the expeditions. Unfortunately he died in October 2016 just as we finished the first draft of the manuscript to this book, that here is published to his memory.
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| 24. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity Exploration from the Arctic to the Antarctic. Part 1: Introduction
- 2015
-
Ingår i: Radioactivity Exploration from the Arctic to the Antarctic.. - 1651-5013. ; 2015-002, s. 1-4
-
Bokkapitel (refereegranskat)abstract
- This book is dedicated to professor emeritus Bengt Forkman (Nuclear Physics, Lund University) who in 1979 took the initiative to arrange an environmental radioactivity research program for the Ymer-80 expedition. He engaged his old friend Bertil Persson whom he during the 1960th inspired to university studies in Lund who just been promoted to professor of Radioecology at the Swedish University of Agricultural Sciences in Uppsala. Bertil Persson was tutor for Elis Holm at Lund University, who for his thesis was engaged in radiochemical analysis of plutonium isotopes in the environment. Elis Holm became deeply involved in management of Ymer-80 and all the following expeditions as well. We found a superior talent for the logistics in Kjell-Åke Carlsson (who was mechanical engineer at the department of radiation physics at Lund University). Without him, we would not have been able to solve all the thousands of practical issues and contacts with authorities and sponsors. He also contributed with the diaries extensive photographic and video documentation of all the expeditions. We have together compiled this book although several others were partly engaged in the various expeditions to whom we are deeply thankful for their contributions. They will appear as contributors in the separate parts of this book: 1. Ymer-80 (Bengt Forkman, Boel Forkman, Lars Ahlgren (diseased) 2. Swedarp 1988-1989 (Per Roos, Birgitta Roos) 3. Arctic Ocean 1991 4. Tundra Expedition 5. Arctic Ocean 1996 (Dan Josefsson, Mats Ericsson)
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| 25. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity Exploration from the Arctic to the Antarctic. Part 2. Ymer-80 Expedition
- 2015
-
Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:003, s. 1-20
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract Levels of natural radioactivity such as 222Rn (radon) and its long-lived daughters 210Pb and 210Po were measured. The radon gas was trapped on cooled charcoal filters and the long-lived daughter products sampled on fibre filters on a daily basis. In addition, short-lived progenies were followed continuously on the filters in order to achieve a time resolution of about one hour. The average 222Rn concentration in air measured during the Ymer-80 expedition in samples north of latitude 78.8 °N, was 33 ± 4 (one standard error) mBq.m-3 during Leg 1 (July-Aug.) , and 105.3 ± 8.3 mBq.m-3 during leg 2 (Aug-Sept.). During a two-week period of persistent polar winds, the mean radon concentration decreased to 19± 5 mBq.m-3. During July, August and September, the monthly average concentrations of 210Pb in air at positions north of 75 °N latitude were 31 ± 15, 89 ± 61 and 105± 57 μBq.m-3 respectively with a the grand average for all 3 months of 75 ± 28 μBq.m-3. An extensive radiochemistry program was also established to measure 134+137Cs and the trans- uranium elements 238+239+240Pu and 241Am in water, sediment and biota. The concentration of 137Cs in surface seawater along the Norwegian coast was quite constant about 157±7 Bq.m-3. At a latitude about 72 oN it stat do decrease exponentially at a rate of 0.43 deg.-1 to about 20 ± 10 Bq.m-3 above 78 oN. The results of 137Cs in sediments indicate that the total integrated area-content of 137Cs in a 1000 m water-column and sediment is about 12 kBq.m-2. In biota, the highest activity concentration of 137Cs about 1000 Bq/kgdwt was found in lichens. The activity concentration of 137Cs in polar bears was about 10 Bq/kgdwt, in seals about 1 Bq/kgdwt, and in birds about 1-7 Bq/kgdwt. The activity-concentration of 137Cs in Fucus and Laminaria was about 1-2 Bq/kgdwt, and the algae/sea-water activity-concentration ratio was about 75. The distribution of the trans-uranium element 239+240Pu in sea water decrease from 14 to 10 mBq.m-3 up to 73°N but increase again to 17 mBq.m-3 at high latitudes while 137Cs decrease. The average 241Am/ 239+240Pu activity ratio was found to be 0.13 ±0.04 (2 S.E), of 31 samples with the range 0.04 - 0.32 in surface water, Deep-water samples have been sampled at latitudes around 80.4 ±1.4 °N and along longitudes 2° W – 45.5 °E. The results of the salinity and activity concentration of 137Cs and 239+240Pu with depth of water are indicate an exponential decrease with depth of both 137Cs and 239+240Pu. In conclusion, about 25% of 137Cs present in the Arctic water and sediments originates from fall- out specific to the area. Another 25% originates from mixing with Atlantic-water from latitudes with higher fall-out. The remaining 50% might originate from European reprocessing facilities. The levels of 241Am in the Svalbard area originate from in situ build-up due to the decay of 241Pu.
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| 26. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity exploration from the Arctic to the Antarctic. Part 3. The SWEDARP expedition Oct 1988 – April 1989
- 2015
-
Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:004, s. 1-17
-
Tidskriftsartikel (refereegranskat)abstract
- The Swedish Antarctic Research Expedition named “SWEDARP” was performed during October 1988 through April 1989. The aim of our project was to study the radioactivity in air and water from Gothenburg to the Antarctic. Between Gothenburg and the Equator, the average activity concentration of 7Be in air was 4.3 ± 0.7 mBq/m3. The activity concentration of 7Be in the South Atlantic down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m3. The average activity concentration of 210Pb in air during autumn 1988 on the route Gothenburg- Montevideo was about 290±270 micro-Bq/m3 and on the return in spring 1989 it was about 230±140 micro-Bq/m3. At the Equator, the average activity concentration of 210Pb in November 1988 was about 630±170 and in April 1989 about 260±210 microBq/m3. In the South Atlantic down to Antarctica during February-March 1989, the activity concentration of 210Pb varied between 11 and 58 micro-Bq/m3. The average activity concentration of 210Po in air during the route Gothenburg- Montevideo in 1988 was about 63±58, and on the return, it was about 60±44 The Swedish Antarctic Research Expedition named “SWEDARP” was performed during October 1988 through April 1989. The aim of our project was to study the radioactivity in air and water from Gothenburg to the Antarctic. Between Gothenburg and the Equator, the average activity concentration of 7Be in air was 4.3 ± 0.7 mBq/m3. The activity concentration of 7Be in the South Atlantic down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m3. The average activity concentration of 210Pb in air during autumn 1988 on the route Gothenburg- Montevideo was about 290±270 micro-Bq/m3 and on the return in spring 1989 it was about 230±140 micro-Bq/m3. At the Equator, the average activity concentration of 210Pb in November 1988 was about 630±170 and in April 1989 about 260±210 microBq/m3. In the South Atlantic down to Antarctica during February-March 1989, the activity concentration of 210Pb varied between 11 and 58 micro-Bq/m3. The average activity concentration of 210Po in air during the route Gothenburg- Montevideo in 1988 was about 63±58, and on the return, it was about 60±44 micro-Bq/m3. At the Equator, the average activity concentration in Nov 1988 was about 132±45, and in April 1989 about 70±60 micro-Bq/m3. The activity concentration of 210Po in the South Atlantic down to Antarctica during February-March 1989 varied between 6 and 14 micro-Bq/m3. The inventory (Bq.m-2) of various deposited ratio nuclides, measured in moss, lichen, soil and lake sediments was: 280 ±110 for 210Pb (excess); 155 ± 95 for 137Cs, 4.6 ± 2.6 for 239+240Pu, 1.6 ± 1.0 for 241Am and, 0.95± 0.5 for 238Pu. 137Cs activity concentration (Bq.m-3) in surface waters samples along the route of the SWEDARP expedition was about 3 Bq.m-3 above 20 °N , decreased to about 2 Bq.m-3 between 20 °N and 40 °S where it decrease to about 1 Bq.m-3 , and at 55 °S (e) there is a further decrease to about 0.3 Bq.m-3. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Concentration factor for 137Cs estimated to 15000 for fish in the Antarctic is much higher than the value of 500 given by The IAEA 1985. Concentration factors for MacroAlgea/Water, was found to be about 1800 in the Antarctic compared to 100 the Arctic. The 239+240Pu activity concentrations in the surface water was about 8 mBq.m-3 in the latitude band 5°-25 °N , about 3 mBq.m-3 in the latitude band 25-5 °N; and about 1,5 mBq.m-3 in the latitude band 0 °S-60 °S. Plutonlum-238 activity was measured in a few water samples from the southern hemisphere with activity ratio of 238Pu to 239+240Pu in the range of 0.14-0.22. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel. The Average activity concentrations (Bq/kgdw,) of 137Cs are in flesh of seals 2.5, penguins 0.2 and, fish 2.5 in liver of seals 0.6 and penguins 0.7 and in kidneys of seals 0.5. The Average activity concentrations (Bq/kgdw) of 210Po are in flesh of seals 8, penguins 4 and, fish 7, in liver of seals 110 and penguins 43 and, fish 5, and in kidneys of seals 91 and of penguins 43. The Average activity concentrations (Bq/kgdw,) of 210Pb are in flesh of seals 0,3, penguins 0,2, and fish 0.6, in liver of seals 4 and penguins 1 and, fish 1, and in kidneys of seals 1 and of penguins 1. The Average activity concentration of 137Cs in samples of Krill is about 1.7 Bq/kgdw of 210Po and 210Pb are in samples of Amphipods, 87 and 1.4 Bq/kgdw respectively. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel.Bq/m3. At the Equator, the average activity concentration in Nov 1988 was about 132±45, and in April 1989 about 70±60 micro-Bq/m3. The activity concentration of 210Po in the South Atlantic down to Antarctica during February-March 1989 varied between 6 and 14 micro-Bq/m3. The inventory (Bq.m-2) of various deposited ratio nuclides, measured in moss, lichen, soil and lake sediments was: 280 ±110 for 210Pb (excess); 155 ± 95 for 137Cs, 4.6 ± 2.6 for 239+240Pu, 1.6 ± 1.0 for 241Am and, 0.95± 0.5 for 238Pu. 137Cs activity concentration (Bq.m-3) in surface waters samples along the route of the SWEDARP expedition was about 3 Bq.m-3 above 20 °N , decreased to about 2 Bq.m-3 between 20 °N and 40 °S where it decrease to about 1 Bq.m-3 , and at 55 °S (e) there is a further decrease to about 0.3 Bq.m-3. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Concentration factor for 137Cs estimated to 15000 for fish in the Antarctic is much higher than the value of 500 given by The IAEA 1985. Concentration factors for MacroAlgea/Water, was found to be about 1800 in the Antarctic compared to 100 the Arctic. The 239+240Pu activity concentrations in the surface water was about 8 mBq.m-3 in the latitude band 5°-25 °N , about 3 mBq.m-3 in the latitude band 25-5 °N; and about 1,5 mBq.m-3 in the latitude band 0 °S-60 °S. Plutonlum-238 activity was measured in a few water samples from the southern hemisphere with activity ratio of 238Pu to 239+240Pu in the range of 0.14-0.22. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel. The Average activity concentrations (Bq/kgdw,) of 137Cs are in flesh of seals 2.5, penguins 0.2 and, fish 2.5 in liver of seals 0.6 and penguins 0.7 and in kidneys of seals 0.5. The Average activity concentrations (Bq/kgdw) of 210Po are in flesh of seals 8, penguins 4 and, fish 7, in liver of seals 110 and penguins 43 and, fish 5, and in kidneys of seals 91 and of penguins 43. The Average activity concentrations (Bq/kgdw,) of 210Pb are in flesh of seals 0,3, penguins 0,2, and fish 0.6, in liver of seals 4 and penguins 1 and, fish 1, and in kidneys of seals 1 and of penguins 1. The Average activity concentration of 137Cs in samples of Krill is about 1.7 Bq/kgdw of 210Po and 210Pb are in samples of Amphipods, 87 and 1.4 Bq/kgdw respectively. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel.
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| 27. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity exploration from the Arctic to the Antarctic. Part 4: The Arctic Ocean-91 expedition
- 2015
-
Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:005, s. 1-14
-
Tidskriftsartikel (refereegranskat)abstract
- The Arctic Ocean expedition in 1991 with the Swedish icebreaker M/S Oden was focused on oceanography and geology. The aim of our project was exploring the activity concentrations in surface air of 7Be, 210Pb. and 210Po in the surface air, radioactive isotopes of Caesium (134Cs, 137Cs) and plutonium (239+240Pu) in seawater. During the cruise in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average activity concentrations in surface air of 7Be was 0.6±0.4 mBq.m-3 , 210Pb 46±34 microBq.m-3 and 210Po 37±23 microBq.m-3 The activity concentration of 137Cs in the surface of the Arctic Ocean was in the range of 8-12 Bq.m-3. When crossing the Nansen basin the activity concentration of 137Cs increased to about 18 Bq.m-3 at 88 °N 80 °E, and there was an accumulation of 137Cs in an area around at 88 °N and 80-100 °E and locally increased activity at 83 °N 10 °E. The 134Cs/137Cs activity ratios was about 0.02 due to the contribution mainly from Sellafield and a few percent contribution from Chernobyl. The 134Cs/137Cs activity ratio decreased to about 0.002-0.005 in areas of high 137Cs activity concentration which exclude contribution of 134Cs of nuclear reactor fuel. The activity concentration of 239+240Pu in the surface of the Arctic Ocean was in the range of 6 - 8 mBq.m-3. But locally the activity concentration of 239+240Pu was found to be increased to 11 mBq.m-3 at 86°N 48-53°E, and to 16 mBq.m-3 at 83°N 10°E.
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| 28. |
- Persson, Bertil R, et al.
(författare)
-
Radioactivity Exploration from the Arctic to the Antarctic. Part 6: The Arctic Ocean-96 expedition
- 2015
-
Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:007, s. 1-22
-
Tidskriftsartikel (refereegranskat)abstract
- The Swedish Arctic Ocean-96 expedition arranged by the Swedish Polar Research Committee took place during 1996 with the Swedish icebreaker M/S Oden. The expedition focused on studying the distribution of radionuclides in different water masses in the central Arctic Ocean. The expedition crossed the Barents Sea, entered the Nansen Basin at the St. Anna Trough, and continued north across the Amundsen Basin. The main part of the expedition was concentrated on the north Lomonosov Ridge and the return route passed the North Pole and went south along 10 oE towards Svalbard. In both legs, water samples in the surface and subsurface layers were collected for the determination of fission products and transuranic elements in seawater and sediment. The highest 137Cs, 90Sr and 129l activities and 134Cs/137Cs activity ratios are found in a band stretching from the northern Lomonosov Ridge, over the North Pole and south along 10-15 oE to 85 oN. The releases from European nuclear fuel reprocessing plants and Chernobyl fallout traced by the 129I and 134Cs/137Cs signals respectively have approximately the same spatial distribution in the Arctic Ocean surface layer. The activity concentration of 90Sr in surface water is about 2 Bq.m-3. For 239+240Pu the lowest concentrations in the surface water of 4 mBq.m-3 was found on the Lomonosov Ridge and in the Makarov Basin. In the Eurasian Basin, the concentrations 239+240Pu are about 13 mBq.m-3 . For all the radionuclides analysed, the water profiles generally show activities decreasing with depth. An exception is the high 137Cs activity concentrations found in the lower halocline layer at the Lomonosov Ridge and Makarov Basin stations. The maxima were not observed in the 90Sr or l29l measurements. It is assumed to be due to a contribution of Chernobyl fallout to the Arctic Ocean surface layers in the years around 1990. Inventories down to 900 m death reveal that between 60-70 % of the 137Cs, 90Sr and in the Arctic Ocean water, are present in the surface layer inflow from the Atlantic. The total inventories down to 900 m in the Eurasian Basin of the Arctic Ocean estimate to 6.7 PBq for 137Cs, 3.4 PBq for 90Sr and 5.3x1028 atoms for 129l.
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| 29. |
- Pham, M. K., et al.
(författare)
-
A new reference material for radionuclides in the mussel sample from the Mediterranean Sea (IAEA-437)
- 2010
-
Ingår i: Journal of Radioanalytical and Nuclear Chemistry. - : Springer Science and Business Media LLC. - 0236-5731 .- 1588-2780. ; 283:3, s. 851-859
-
Tidskriftsartikel (refereegranskat)abstract
- A new Reference Material (RM) for radionuclides in mussel (Mytilus galloprovincialis) from the Mediterranean Sea (IAEA-437) is described and the results of the certification process are presented. Four radionuclides (K-40, U-234, U-238, and Pu239+240) have been certified, and information values on massic activities with 95% confidence intervals are given for nine radionuclides (Cs-137, Pb-210(Po-210), Ra-226, Ra-228, Th-228, Th-230, Th-232, U-235, and Am-241). Results for less frequently reported radionuclides (Sr-90, I-129, Pu-238, Pu-239, and Pu-240) are also reported. The RM can be used for quality assurance/quality control of the analysis of radionuclides in mussel samples, for the development and validation of analytical methods and for training purposes. The material is available in 200 g units.
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| 30. |
- Pham, M. K., et al.
(författare)
-
Certified reference material for radionuclides in fish flesh sample IAEA-414 (mixed fish from the Irish Sea and North Sea)
- 2006
-
Ingår i: Proceedings of the 15th International Conference on Radionuclide Metrology and its Applications (Applied Radiation and Isotopes). - Amsterdam : Elsevier BV. - 0969-8043 .- 1872-9800. ; 64:10-11, s. 1253-1259
-
Konferensbidrag (refereegranskat)abstract
- A certified reference material (CRM) for radionuclides in fish sample IAEA-414 (mixed fish from the Irish Sea and North Seas) is described and the results of the certification process are presented. Nine radionuclides (K-40, Cs-137, Th-232, U-234, U-235, U-238, Pu-238, Pu239+240 and Am-241) were certified for this material. Information on massic activities with 95% confidence intervals is given for six other radionuclides (Sr-90, Pb-210(Po-210), Ra-226, Pu-239, Pu-240 Pu-241). Less frequently reported radionuclides (Tc-99, I-129, Th-228, Th-230 and Np-217) and information on some activity and mass ratios are also included. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in fish sample, for the development and validation of analytical methods and for training purposes. The material is available from IAEA, Vienna, in 100 g units.
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| 31. |
- Rääf, C., et al.
(författare)
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On the presence of plutonium in Madagascar following the SNAP-9A satellite failure
- 2017
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Ingår i: Journal of Environmental Radioactivity. - : Elsevier BV. - 0265-931X. ; 177, s. 91-99
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Tidskriftsartikel (refereegranskat)abstract
- This study examined the Pu-238 and 239+249PU activity concentration and the Pu-240/Pu-239 atomic ratio in peat bogs sampled in 2012 from marshlands in central Madagascar. The purpose was to investigate the., presence of plutonium isotopes, (238,) (239,) Pu-240, from the 1964 satellite failure carrying a SNAP-9A radiothermal generator. With an average Pu-238/Pu239+240 activity ratio of 0.165 +/- 0.02 (decay corrected to 1964), the peat bogs in Madagascar exhibit similar values as the ones found in the southeastern African continent, except they are one order of magnitude higher than expected (0.025) from global fallout in the Southern Hemisphere. The Pu-240/Pu-239 atomic ratio showed a distinct decrease for layers dating back to the mid-1960s (down to 0.069 compared with an anticipated ratio of 0.17 for global fallout), indicating that the SNAP-9A failure also resulted in an elevated deposition of Pu-239. The obtained results demonstrate that further Pu analysis in Madagascar and in southeastern continental Africa is necessary to fully account for the regional Pu deposition from the SNAP-9A event. (C) 2017 Elsevier Ltd. All rights reserved.
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