7. Table 1 Effective dose rates to adults from uranium and thorium series radionuclide based on tissue concentration and in take rates (from table 20 of annex B, UNSCEAR 2000) For Adult Annual intake Ra-226 = 22 Bq Annual limit intake (ALI) = 74 kBq
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9. Weapons testing Table 2 Fission and fusion yields of atmospheric nuclear tests (from table 4 of annex C, UNSCEAR 2000)
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11. Radionuclide concentrations in the diet of residents in a high level natural radiation area in Iran H . Samavat , M. R. D. Seaward , S . M . R . Aghamiri and F . Reza - Nejad (1) Department of Medical Physics, Hamadan University of Medical Sciences, Hamadan, Iran (2) Department of Geography and Environmental Science, University of Bradford, Bradford, BD7 1DP, UK (3) Department of Physics, Shahid Beheshti University, Tehran, Iran (4) Department of Physics, University of Sistan and Balouchestan, Zahedan, Iran
12. Introduction In some areas of the world, the average annual effective dose is considerably more than the world average [ 2 ]
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14. Fig 1 shows the geographical map of Ramsar with its HLNRAs (Sohrabi and Esmaili, 2000).
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18. Materials and methods Fig . 1 Location of hot springs and sampling locations in the Ramsar area
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22. Materials and methods Gamma spectrometry using a Canberra high purity germanium ( HPGe ) detector with a relative efficiency of 40% . The detector was shielded by 10 cm lead to reduce possible background contribution from the surrounding material and cosmic rays
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24. Effective dose rate calculation ***the dose coefficient for Ra-226, D f = 0.2 μ Sv/Bq and for Cs-137, Df = 1.3 x10 -2 μ Sv/Bq
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27. Results Table 4 Concentrations (± SE) of 226 Ra in local products and environmental samples
28. Results Table 5 Estimated annual 226 Ra intake due to consumption of local vegetables in Talesh-Mahalleh of Ramsar, and resulting annual effective dose ** Annual limit to intake for Ra-226 = 74 kBq
29. Results Table 6 Estimated annual 137 Cs intake due to consumption of local vegetables in Talesh Mahalleh of Ramsar, and resulting annual effective dose ** Annual intake Ra-226 = 22 Bq Annual limit to intake for Cs-137 = 6 MBq
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