Transfer of tritium to crops, animals and fishes during an accidental release of tritium and its retension

氚意外释放过程中氚向农作物、动物和鱼类的转移及其滞留

• 批准号: 09308016
• 负责人: ICHIMASA Michiko
• 金额: $ 21.06万
• 依托单位: IBARAKI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09308016/
• 关键词: Tritium; Environmental behavior; Tritiated water; Deuterium; Heavy water; DィイD22ィエD2O release experiment; Organically-bound tritium; 動態解析モデル; 重水素野外放出実験

Tritium is released into the environment from unclear facilities including future unclear fusion reactors during ordinary operation or by an accident. Tritium toxicity is markedly different depending on its chemical form, tritiated water (HTO), molecular tritium (HT) and organically bound tritium (OBT), and HTO is four figures more radiotoxic than HT. From a view point of health physics, studies on tritium behavior in the environment are necessary for an accurate dose assessment ; such as actual HT oxidation in the local environment, transfer of HTO to soil, plants and animals, and OBT formation and tritium elimination in them. However, field experiments on environmental behavior of tritium are quite difficult to do because of the public acceptance problem. Thus heavy water (DィイD22ィエD2O) vapor release experiments into a plastic greenhouse put on a field at Mito site of IBARAKI University were conducted in August 1997, 1998, 1999, using DィイD22ィエD2O as a substitute for HTO under different conditions. In the 1997 experiment, DィイD22ィエD2O vapor release was for 2 days. In the 1998 experiments, DィイD22ィエD2O vapor was released in two open top plastic houses, one as daytime release and the other as nighttime release. In 1999, two DィイD22ィエD2O vapor release experiments, daytime release and nighttime release, were conducted in the air conditioned closed plastic greenhouses. The following studies were carried out and the results were obtained : uptake kinetics of DィイD22ィエD2O into leaves and edible parts of vegetation including rice, soybean, tomato, radish and so on, DィイD22ィエD2O concentration ratios in free water of vegetation to air moisture under steady-state conditions, OBD formation in crops, elimination kinetics from vegetation after DィイD22ィエD2O vapor release, transfer of DィイD22ィエD2O in water and aquatic organisms, deposition of DィイD22ィエD2O into soil and its reemission, and formation of molecular deuterium and deuteriated methane.

氚是从核设施释放到环境中的，包括未来核聚变反应堆在正常运行或事故中。氚的毒性因其化学形态、氚化水（HTO）、分子氚（HT）和有机结合氚（OBT）的不同而明显不同，HTO的放射毒性比HT高4位数。从健康物理学的角度来看，研究氚在环境中的行为对准确的剂量评估是必要的;例如，在当地环境中的实际HT氧化，HTO向土壤、植物和动物的转移，以及OBT的形成和氚的消除。然而，氚的环境行为的现场实验是相当困难的，因为公众接受的问题。1997年8月、1998年8月、1999年8月在茨木大学水户基地的塑料温室内进行了重水（D_（22）O_（22））蒸气释放实验，在不同条件下使用D_（22）O_（22）O_（22）O作为HTO的替代物。在1997年的实验中，D20-D22-D2 O蒸气释放持续了2天。在1998年的实验中，在两个开顶的塑料房子里释放了D-22-D2 O蒸气，一个是白天释放，另一个是夜间释放。1999年，在封闭式塑料温室中进行了两次D2 O蒸气释放试验，白天释放和夜间释放。进行了以下研究并获得了结果：水稻、大豆、番茄、萝卜等植物叶片和可食部分对D_（22）O_（20）的吸收动力学，稳态条件下植物自由水中D_（22）O_（22）蒸气释放后植物的消除动力学，D D22 D2 O在水和水生生物中的转移，D D22 D2 O在土壤中的沉积和再排放，以及分子氘和氘代甲烷的形成。

项目成果

N. Momoshima, H.Kakiuchi, T.Okai, S. Yokoyama, H.Noguchi, M.Atarashi, H.Amano, S.Hisamatsu, M.Ichimasa, Y.Ichimasa, Y.Maeda.: "Uptake kinetics of deuteriated water vapor by plants: Experiments of DィイD22ィエD2O release in a greenhouse as a substitute for tri

N. Momoshima、H.Kakiuchi、T.Okai、S. Yokoyama、H.Noguchi、M.Atarashi、H.Amano、S.Hisamatsu、M.Ichimasa、Y.Ichimasa、Y.Maeda.：“氘化物的摄取动力学植物产生的水蒸气：在温室中释放 D22D2O 作为三水蒸气替代品的实验

M. Atarashi, H.Amano, M.Ichimasa & Y.Ichimasa: "Deposition of DィイD22ィエD2O from air to plant and soil during an experiment of DィイD22ィエD2O vapor release into a vinyl house"Fusion Engineering and Design. 42. 133-140 (1998)

M. Atarashi、H.Amano、M.Ichimasa 和 Y.Ichimasa：“在将 D22D2O 蒸气释放到乙烯基房屋中的实验中，D22D2O 从空气中沉积到植物和土壤中”Fusion Engineering and Design，1998 年。 ）

S. Yokoyama, H.Noguchi, S.Fukutani, M.Ichimasa & Y.Ichimasa: "Reemission of heavy water deposited in soil to atmosphere."Fusion Engineering and Design. 42. 141-148 (1998)

S.横山、H.Noguchi、S.Fukutani、M.Ichimasa

M.Saito: "Blood tritium level as a conservative estimation of soft tissue dose after tritium injection in mice" Health Physics. 74. 561-567 (1998)

M.Saito：“血液氚水平是对小鼠注射氚后软组织剂量的保守估计”健康物理学。

M.Ichimasa et al.: "In vitro Determination of Oxidation of Atmospheric Tritium Gas in Vegetation and Soil in Ibaraki and Gifu,Japan"Journal of Radiation Research. 40. 243-251 (1999)

M.Ichimasa 等人：“日本茨城县和岐阜县植被和土壤中大气氚气氧化的体外测定”辐射研究杂志。