著者
山下 順助 滝澤 行雄
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.30, no.3, pp.239-242, 1995 (Released:2010-02-25)
参考文献数
2
著者
山口 彦之 吉田 芳和 田野 茂光 備後 一義 片桐 浩
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.20, no.4, pp.349-356, 1985 (Released:2010-02-25)
参考文献数
23

Tradescantia (clone KU-7) were grown at three points near a site of nuclear power plants and somatic mutation frequencies in Tradescantia stamen hairs were investigated for three years. The two points are located in the prevailing down-wind sector of the site. Mutational events in stamen hair cells were scored every day from the end of April to October for three years. In parallel with this observation, factors which have been thought to affect mutation induction, such as temperature, humidity, insolation, pollutants, radioactivity in the buds were measured at the three points. The daily exposure and radioactive concentration at three points due to the amount of the radioactive nuclide released from the nuclear power plant were calculated.Mutation frequencies fluctuated daily, but they were estimated rather constant on average at three sites. Increase of radioactivities in the buds or other plant tissues was not detected during this experiment. The daily exposure and radioactive concentration were very low, for example, the ratio of the maximum daily exposure to the doubling dose was less than 1×10-7.It has been definitely shown by this field experiment that radionuclide released from the nuclear power plants can not induce significant mutation of Tradescantia.It was concluded that Tradescantia stamen hair system was not appropriate to monitor the environmental radiation from the power reactor.
著者
林田 敏幸 佐々木 洋 浜田 信行 立崎 英夫 初坂 奈津子 赤羽 恵一 横山 須美
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.52, no.2, pp.88-99, 2017 (Released:2017-07-29)
参考文献数
54
被引用文献数
5

In March 2011, the accident occurred at the Fukushima Daiichi Nuclear Power Plant of Tokyo Electric Power Company. During recovery from critical situations, the radiation dose for some emergency workers exceeded the effective dose limit recommended for an emergency situation. A month after the accident, the International Commission on Radiological Protection issued a statement on tissue reactions recommending significant reduction of the equivalent dose limit to the lens of the eye. Many radiation workers will need to be involved in treatment of water contaminated with radionuclides, fuel debris retrieval, and decommissioning of reactors for a long period of time. Thus, the optimized radiation control in the fields, exposure reduction, prevention of tissue reactions, and reduction of stochastic risks for workers becomes necessary. This paper discusses issues in relation to radiation protection of the ocular lens in such recovery workers, from the viewpoint of radiation exposure of workers, its management, manifestations and mechanisms of the lens effects.
著者
藤通 有希 小佐古 敏荘 吉田 和生 浜田 信行
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.48, no.2, pp.86-96, 2013 (Released:2014-03-06)
参考文献数
57
被引用文献数
3 2 1

The International Commission on Radiological Protection (ICRP) has classified radiation cataract as tissue reactions (formerly known as deterministic effects or non-stochastic effects) for which a threshold dose exists, and recommended an equivalent dose limit for the lens of the eye to prevent vision-impairing cataracts. A recommended occupational dose limit has been 150 mSv/year predicated on the threshold of >8 Sv since the 1980 Brighton Statement, but was drastically lowered by the 2011 Seoul Statement to 20 mSv/year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv. Such a new limit was included immediately in the Interim Edition of General Safety Requirements Part 3 of the International Atomic Energy Agency. In contrast, a dose limit of 15 mSv/year for members of the public has not been changed since the 1990 Recommendations. This paper considers the impacts of a new limit focusing on conformity with cancer risk management, the necessity of the public dose limit in planned exposure situations and the occupational dose limit in emergency exposure situations. Potential issues arising from its implementation shall also be discussed especially in terms of the compensation problem and the possibility of exceeding a dose limit in interventional cardiologists.
著者
古田 悦子 中原 弘道
出版者
日本保健物理学会
雑誌
保健物理 : hoken buturi (ISSN:03676110)
巻号頁・発行日
vol.43, no.4, pp.341-348, 2008-12
被引用文献数
2 4

Cosmetics claiming hormesis effects are available through Internet. Although the hormesis effect is explained in each product of cosmetics, there is no explanation about the radiation source. The existence of the progeny nuclides of Th and U series (RI) was comfirmed by the γ-ray spectroscopy using a HPGe detector. The highest radioactivity densities were 68Bq/g of the Th-series included in the hormesis powder. Because the particles containing RI were of the size of 1-10 micrometer by observing and analyzing SEM-EDX, there is a risk of inhaling the powder to the deep into the lungs. Furthermore, as about 1% RI was dissolved in water, the uptake of the RI to the body would be possible. The highest value of the evaluation of uniform radiation exposure to some organs by the continuous usage for 10 years was 5.5mSv/y of the hormesis powder inhalation to the lung. Furthermore, the calculated quantity of the radioactivity of progeny of ^<222>Rn deposited in the body after continuous use of the hormesis cream every day for one year becomes 24Bq. The possibility of accumulation of the radioactivity in the body from the hormesis cosmetics cannot be denied. The addition of the radioisotope to cosmetics is prohibited in some EU countries by the regulation. It's proposed in this paper that the legitimacy of the addition of the radioisotope should be seriously re-examined.
著者
辻村 憲雄
出版者
一般社団法人日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.54, no.1, pp.40-44, 2019-04-18 (Released:2019-09-03)
参考文献数
21

Rainwater containing radioactive materials originating from the USA’s nuclear weapon test conducted at Bikini Atoll was observed throughout Japan in 1954. It has been reported that the maximum gross beta activity observed at that time in Kyoto was 523 pCi/mL (19,000 Bq/L). This measurement, however, focused on the gross beta activity contained in a small amount of rain sampled at the beginning of rainfall, which is different from present observations that are based on the average gross beta activity contained in rain collected during a 24-h period. As a result of reviewing and converting the 1954 data to be equivalent to current measurement, the maximum value was reduced to 50 pCi/mL (1,800 Bq/L), with a resultant surface deposition density of 310 mCi/km2 (11,000 MBq/km2). These values are well below 1/10 of the past maximum observed a few days after China’s fifth nuclear weapon test in 1966.
著者
宮本 霧子
出版者
Japan Health Physics Society
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.43, no.1, pp.50-59, 2008 (Released:2010-08-05)
参考文献数
9

The international program, known as the EMRAS (Environmental Modeling for Radiation Safety) project was carried out in 2003-2007. “The working group for modelling of tritium and carbon-14 transfer to biota and man” took an active part in the EMRAS by presenting the eight scenarios for the purpose of the validation of the environmental tritium model. Three scenarios were concerned about uptake and depuration of tritium by bivalves and various biological species in a steady state lake. Two scenarios dealt with tritium uptake of soybean and pine tree, other two did pig metabolism and various products from a farm land. One scenario was designed to estimate human dose exposed by a hypothetical shot of tritium release in the atmosphere. OBT definition and revision of parameter values in the Handbook, IAEA-TRS No. 364 were also carried out.
著者
村上 博幸 箕輪 雄資 新野 二男 松井 智明 大畑 勉
出版者
Japan Health Physics Society
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.16, no.3, pp.255-258, 1981 (Released:2010-02-25)
参考文献数
2
被引用文献数
1 1
著者
下 道國
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.51, no.1, pp.75-78, 2016 (Released:2016-07-06)
参考文献数
6

5 0 0 0 OA Internal Dosimetry

著者
Wei Bo LI
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.53, no.2, pp.72-99, 2018 (Released:2018-09-13)
参考文献数
132
被引用文献数
5

Fifty-five years after discovery of x-rays by Wilhelm Conrad Röntgen in 1895, International Commission on Radiological Protection (ICRP) established a committee on permission internal exposure. Natural and man-made radionuclides can enter human body, cause damage effect and lead to health risk; on the other hand, radionuclides can cure cancers and other non-cancer diseases by irradiating the malignant cells and tissues. The radiation doses delivered to the tissues and organs are inevitable to assess risk or to judge the benefit of application of radiation on humans. In this article, basic methodology for dose assessment of internally deposited radionuclides is reviewed. After brief introduction of interactions and effects of radiation, the biokinetic models developed by ICRP for incorporation of radionuclides in humans are described. Then, the dosimetric formula generalized by ICRP and Committee on Medical Internal Radiation Dose (MIRD) is presented. Treatment of decay products and uncertainty analysis in internal dosimetry are especially addressed. Moreover, applications of internal dosimetry in radiation protection, internal exposure monitoring, radon inhalation dosimetry and nuclear medicine are presented with several calculation examples. At last, the future perspective of internal dosimetry is discussed. In an appendix basic internal dosimetric quantities are provided.
著者
山田 裕司 小泉 彰 宮本 勝宏 稲葉 次郎
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.29, no.3, pp.283-289, 1994 (Released:2010-02-25)
参考文献数
11
被引用文献数
1 1

Decontamination Factors (DFs) of HEPA filter were measured against 239Pu oxide aerosols. Collection performance of HEPA filter media was investigated using monodisperse NaCl aerosols at various air flow face velocities. From the penetration curves the most penetrating particle size, MPPS, and the maximum penetration, Pmax, were obtained in each face velocity. The MPPSs at 0.8-11cm s-1 flow were not found in 0.3μm size range but in 0.1-0.15μm size range. The reciprocal of Pmax, which means the minimum of decontamination factor, DFmin, linearly increased with decreasing face velocity in a logarithmic paper. Experimental DFs against Pu aerosols in the MPPS range were nearly equal to the DFmin, and the others were always larger than the DFmin. This means that there are no differences between Pu and NaCl aerosols in terms of filtration. The DFmin estimated from the nonradioactive test aerosols is important for evaluating the performance of HEPA filters in the radiation protection field.
著者
Chanis PORNNUMPA Kazuki IWAOKA Naofumi AKATA Masahiro HOSODA Atsuyuki SORIMACHI Shinji TOKONAMI
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.51, no.2, pp.115-121, 2016 (Released:2016-08-09)
参考文献数
27
被引用文献数
4

Namie Town, Fukushima Prefecture was instituted as an evacuation zone and a controlled area after the Fukushima Daiichi Nuclear Power Plant accident in April, 2011 which immediately resulted in a significant amount of radionuclides leakage to the environment. In this study, a car-borne survey utilizing a NaI(Tl) scintillation survey meter was carried out along ordinary roads and forest areas in Namie Town from September 29th to October 1st, 2011 to measure the absorbed dose rate by gamma-rays from 137Cs (T1/2: 30.05 y) and 134Cs (T1/2: 2.04 y) for the estimation of the radiation levels over long periods of time. The similar surveys were conducted again on August 22nd-24th, 2014 and September 14th-16th, 2015 using a NaI(Tl) scintillation spectrometer. The ratios of data obtained from urban areas to total surveyed areas in the same measurements were 27%, 34% and 48% in 2011, 2014 and 2015, respectively. The ratios of those measured from forest areas and mountain regions were 73%, 66% and 52% in 2011, 2014 and 2015, respectively. The absorbed dose rates in air obtained from these surveys were used to draw dose rate distribution maps to monitor the variation of the dose rates, and the distribution was found to be heterogeneous. The maximum value, minimum value and geometric mean of the absorbed dose rates in air for 2011 were estimated to be 47.6, 0.15 and 3.7 μGy h-1, respectively. The values for 2014 were estimated to be 5.8, 0.09 and 1.2 μGy h-1, respectively. In 2015, the values were estimated to be 5.6, 0.05 and 0.9 μGy h-1, respectively. The annual effective doses in 2014 and 2015 dropped by 66% and 75% from 2011, respectively. The annual effective doses estimated in 2014 and 2015 were lower than the annual effective dose limit of 20 mSv recommended by the Japanese government for an evacuation directive lift in the prepared area.
著者
吉岡 勝廣 飯田 孝夫
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.42, no.1, pp.53-62, 2007 (Released:2010-08-05)
参考文献数
39
被引用文献数
2 4

We compared the periodic characteristics of the atmospheric radon concentration on the land and ocean, using data simultaneously measured at Oki Island in the Sea of Japan and Matsue, which is located 70km south of the island and on the Shimane peninsula. The radon concentration was the highest in the fall at Matsue and in the winter at Oki Island and the lowest during the summer at both locations. The frequency distributions and the annual periodic variations of the arriving pathways of the air masses and these radon concentrations at Matsue and Oki Island showed the same tendency. At Matsue, the monthly average of diurnal minimum of the radon concentration was highest in the winter that was three month late from the maximum season of the monthly average of all measurements. The monthly average of radon concentration at Matsue showed the positive correlation between the monthly occurrence times of temperature inversion. The annual periodic variation of the radon concentration at Oki Island depends on the long-term variation of the distribution of arriving pathways of the air masses.
著者
細田 正洋 井上 一雅 岡 光昭 大森 康孝 岩岡 和輝 床次 眞司
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.51, no.1, pp.27-40, 2016 (Released:2016-07-06)
参考文献数
55
被引用文献数
1

Many nuclear facilities are located in Aomori Prefecture, Japan. However, no detailed dose rate distribution map of Aomori Prefecture, including its mountain regions has been reported since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Thus, a car-borne survey which used a 3-in × 3-in NaI(Tl) scintillation spectrometer was done throughout the prefecture for the purposes of making a dose distribution map and estimating the annual external dose. These results have been published in the same issue of this journal. On the other hand, many researchers have performed car-borne surveys in Fukushima Prefecture after the FDNPP accident. In this paper, the methods of car-borne survey of the present author are explained in detail. 1) The relationship between the total counts per minute of a gamma-ray pulse height distribution and an absorbed dose rate in air is examined for the estimation of dose rate conversion factor. 2) The relationship between count rates outside and inside the car is examined for the estimation of the shielding factor by car body. 3) The uncertainties to the counts inside the car, the dose rate conversion factor and the shielding factor are evaluated according to the Guide to the Expression of Uncertainty in Measurement published by the Joint Committee for Guides in Metrology. 4) The gamma-ray pulse height distributions are unfolded using a 22 × 22 response matrix for the analysis of activity concentrations in soil of 40K, 238U and 232Th and the contributions of their nuclides to absorbed dose rate in air. 5) The distribution map of absorbed dose rate in air of Aomori Prefecture is drawn using the Generic Mapping Tool which was developed by Hawaii University.
著者
Masahiro HOSODA Kazumasa INOUE Mitsuaki OKA Yasutaka OMORI Kazuki IWAOKA Shinji TOKONAMI
出版者
日本保健物理学会
雑誌
保健物理 (ISSN:03676110)
巻号頁・発行日
vol.51, no.1, pp.41-50, 2016 (Released:2016-07-06)
参考文献数
50
被引用文献数
2 25

Many nuclear facilities are located within Aomori Prefecture, Japan. However, no detailed dose rate distribution map of Aomori Prefecture, including its mountain regions has been reported since the Fukushima Daiichi Nuclear Power Plant accident. A car-borne survey which used a 3-in × 3-in NaI(Tl) scintillation spectrometer was carried out throughout the prefecture for the purposes of making a dose distribution map and estimating the annual external dose. The average absorbed dose rate in air and the annual effective dose were found to be 22 ± 5 nGy h-1 and 0.20 ± 0.08 mSv, respectively. These average values for all of Aomori Prefecture were respectively 44% and 59% of the nationwide average values. The average values with standard deviations of activity concentrations in soil of 40K, 238U and 232Th were 234 ± 148, 15 ± 6, 12 ± 6 Bq kg-1, respectively. The average values of contributions of 40K, 238U and 232Th to absorbed dose rates in air were 39%, 29% and 32%, respectively. The contributions of 134Cs and 137Cs to the absorbed dose rates in air were judged to be negligible.