Biogeocheroical studies on the accumulation and cycling of iodine in the environment
Project/Area Number |
17340169
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Geochemistry/Astrochemistry
|
Research Institution | Gakushuin University |
Principal Investigator |
MURAMATSU Yasuyuki Gakushuin University, Faculty of Science, Professor (70166304)
|
Co-Investigator(Kenkyū-buntansha) |
AMACHI Seigo Chiba University, Faculty of Bioresorces, Assistant Professor (80323393)
MATSUZAKI Hiroyuki Tokyo niversity, MALT, Associate Professor (60313194)
MATSUMOTO Ryo University of Tokyo, Department of Geology, Professor (40011762)
|
Project Period (FY) |
2005 – 2007
|
Project Status |
Completed (Fiscal Year 2007)
|
Budget Amount *help |
¥15,900,000 (Direct Cost: ¥15,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2007: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2006: ¥5,200,000 (Direct Cost: ¥5,200,000)
Fiscal Year 2005: ¥6,800,000 (Direct Cost: ¥6,800,000)
|
Keywords | iodine / iodine-129 / biogeochemistry / analytical method / chemical species / underground brines / soil / AMS (accelerator mass snectrometry) |
Research Abstract |
Iodine is an essential nutrient element, because of its role in the thyroid gland of human and animals. However, geochemical and environmental behavior of this element is not sufficiently known. For example, iodine-rich brines, which contain iodine more than 1000 times higher than that of seawater, occure in several places in Japan, although their origins are not well understood. From a radiological viewpoint, considerable attention should be paid to the levels and behavior of radioiodine, specifically ^<129>I (half-life 16 million years), in the environment. We have studied sensitive analytical methods for ^<129>I and stable iodine and applied them to biogeochemical systems. Microbial activities on the accumulation and transformation of iodine species were also studied. Main results obtained are as follows: (1) Concentrations of iodine and some other elements in underground waters(including brines)varied very widely from<0.01 to 140 ppm. Analytical results obtained from pore waters in Nankai-Trough sediments associated with methane. In order to determine the ages of iodine in such brine samples using ^<129>I systematics, ^<129>L/^<127> I ratios in selected samples were measured by AMS. (2) Concentrations of ^<129>I in surface soil samples obtained far from different places in Japan are in the range 1.4×10^<-5>- 4.5×10^<-3> Bq/Kg. Markedly higher ^<129>I concentrations were observed in surface soil samples collected from Tokai-mura, where a spent fuel reprocessing plant is located. The ^<129>I was found to be accumulated in surface soil layers. (3) Experiments using different types of microorganisms showed that there are bacteria participating in the transformation of iodine species, e. g. iodide to methyl iodide, iodate to iodide, iodide to molecular iodine. We also found iodine accumulating bacteria.
|
Report
(4 results)
Research Products
(89 results)
-
-
-
-
-
-
-
-
-
-
[Journal Article] Halogen concentrations in pore waters and sediments of the Nankai Trough, Japan : Implications for the origin of gas hydrates2007
Author(s)
Y., Muramatsu, T., Doi, H., Tomaru, U., Fehn, R., Takeuchi, R., Matsumoto
-
Journal Title
Applied Geochemistry 22
Pages: 534-556
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
[Journal Article] Analysis of iodine-129 by AMS2006
Author(s)
Y., Takada, Y., Muramatsu, H., Matsuzaki, K., Kato, S., Yoshida
-
Journal Title
Proceedings of the Seventh Workshop on Environmental Radioactivity, KEK Proceedings 7
Pages: 235-241
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
[Journal Article] AMSを用いた土壌中ヨウ素-129分析2006
Author(s)
高田ゆかり, 村松康行, 松崎浩之, 加藤和浩, 吉田聡
-
Journal Title
Proceedings of the Seventh Workshop on Environmental Radioactivity, KEK Proceedings 2006-5 7
Pages: 235-241
Related Report
-
-
-
-
-
-
-
-
-
-
[Journal Article] Iodine and boron in Mariana serpentinite mud volcanoes (ODP Legs 125 and 195) : implications for forearc processes and subduction recycling2005
Author(s)
G. T., Snyder, I. P., Savoy, Y., Muramatsu
-
Journal Title
Proc. ODP (Ocean Drilling Projects) (Eds : Shinohara, M., Salisbury, M. H., and Richter, C. ) 195
Pages: 1-18
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
[Presentation] AMS analysis on the secular variations of C-14 in grains. (in Japanese)2006
Author(s)
Y., Muramatsu, T., Kubo, R., Iwasaki, H., Matsuzaki, Y., Tsuchiya-Sunohara, K., Kato
Organizer
Environmental Radioactivity Study Meeting
Place of Presentation
KEK/Tsukuba
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
[Presentation] Vertical distribution of halogens (I, Br, Cl) in pore water collected from Nankai Trough sediments. (in Japanese)2006
Author(s)
Y., Muramatsu, T., Doi, R., Matsumoto, R., Takeuchi, H., Tomaru, U., Fehn
Organizer
Annual Meeting of Geochemical Society of Japan
Place of Presentation
Nippon University (Tokyo)
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
-
-
-
[Presentation] Depth profile of iodine and bromine in pore waters collected from the Nankai Trough2005
Author(s)
T., Doi, Y., Muramatsu, R., Matsumoto, R., Takeuchi, H., Tomaru, U., Fehn
Organizer
Goldschmidt Conference
Place of Presentation
Moscow/Idaho, USA
Description
「研究成果報告書概要(欧文)」より
Related Report
-
[Presentation] Origin of iodine rich brine. (in Japanese)2005
Author(s)
Y., Muramatsu, T., Doi, R., Matsumoto, R., Takeuchi, H., Tomaru, U., Fehn
Organizer
FIU Meeting
Place of Presentation
Chiba University
Description
「研究成果報告書概要(欧文)」より
Related Report
-
-
-
-