• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.270-277
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• 2001

To observe the stimulating effect of low dose ${\gamma}$ radiation on the dormancy breaking and growth, microtubers induced in vitro of two potato (Solanum tuberosum L. cv. Dejima and cv. Superior) cultivars with different storage duration were irradiated with ${\gamma}$ radiation at the dose of $0.5{\sim}30$ Gy. Sprouting rate, growth and tuber yield of ‘Dejima’ microtuber were increased by ${\gamma}$ radiation in the range of $2{\sim}16$ Gy. In the microtuber of ‘Superior’, the sprouting rate was promoted by 2 Gy and 4 Gy irradiation, and the growth and tuber yield by 0.5 Gy and 4 Gy irradiation. There were not that much difference in chlorophyll content of potato plantlet by the low dose ${\gamma}$ irradiation. These results suggested that low dose ${\gamma}$ radiation stimulated the dormancy breaking and potato growth.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.1.1-1.13
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• 2016

Objectives To investigate the accuracy and scientific validity of the current very low risk factor for hereditary diseases in humans following exposures to ionizing radiation adopted by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Commission on Radiological Protection. The value is based on experiments on mice due to reportedly absent effects in the Japanese atomic bomb (A-bomb) survivors. Methods To review the published evidence for heritable effects after ionising radiation exposures particularly, but not restricted to, populations exposed to contamination from the Chernobyl accident and from atmospheric nuclear test fallout. To make a compilation of findings about early deaths, congenital malformations, Down's syndrome, cancer and other genetic effects observed in humans after the exposure of the parents. To also examine more closely the evidence from the Japanese A-bomb epidemiology and discuss its scientific validity. Results Nearly all types of hereditary defects were found at doses as low as one to 10 mSv. We discuss the clash between the current risk model and these observations on the basis of biological mechanism and assumptions about linear relationships between dose and effect in neonatal and foetal epidemiology. The evidence supports a dose response relationship which is non-linear and is either biphasic or supralinear (hogs-back) and largely either saturates or falls above 10 mSv. Conclusions We conclude that the current risk model for heritable effects of radiation is unsafe. The dose response relationship is non-linear with the greatest effects at the lowest doses. Using Chernobyl data we derive an excess relative risk for all malformations of 1.0 per 10 mSv cumulative dose. The safety of the Japanese A-bomb epidemiology is argued to be both scientifically and philosophically questionable owing to errors in the choice of control groups, omission of internal exposure effects and assumptions about linear dose response.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.328-331
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• 2000

Maize (Zea mays L. cv. kosungjaerae and cv. youngwoljaerae) seeds were irradiated with the dose of $0.5{\sim}20$ Gy by $^{60}Co\;{\gamma}-ray$ radiation to investigate the effect of the low dose ${\gamma}-ray$ radiation on the germination rate, early growth and yield. The low dose radiation was able to improve the germination rate and early growth in maize, but the optimal radiation doses were different depended on kinds of cultivars. High stimulatory effect in early growth of maize was observed in 2 Gy irradiation group of kosungjaerae cultivar and in 12 Gy irradiation group of youngwoljaerae cultivar. The optimal radiation dose for the enhancement of yield and yield components in maize was 8 Gy in kosungjaerae cultivar and $4{\sim}12$ Gy in youngwoljaerae cultivar.

• Journal of Preventive Medicine and Public Health
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• v.33 no.2
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• pp.165-173
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• 2000

Objectives : To assess the availability of the glycophorin A (GPA) assay to detect the biological effect of ionizing radiation in workers exposed to low-doses of radiation. Methods : Information on confounding factors, such as age and cigarette smoking was obtained on 144 nuclear power plant workers and 32 hospital workers, by a self-administered questionnaire. Information on physical exposure levels was obtained from the registries of radiation exposure monitoring and control at each facility. The GPA mutant assay was performed using the BR6 method with modification by using a FACScan flow cytometer. Results : As confounders, age and cigarette smoking habits showed increasing trends with GPA variants, but these were of no statistical significance. Hospital workers showed a higher frequency of the GPA variant than nuclear power plant workers in terms of the NO variant. Significant dose-response relationships were obtained from in simple and multiple linear regression models. The slope of the regression equation for nuclear power plant workers was much smaller than that of hospital workers. These findings suggest that there may be apparent dose-rate effects. Conclusion : In population exposed to chronic low-dose radiation, the GPA assay has a potential to be used as an effective biologic marker for assessing the bone marrow cumulative exposure dose.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1135-1135
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• 2004

• Journal of Radiation Protection and Research
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• v.24 no.3
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• pp.123-129
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• 1999

Tomato (Lycopericum esculentum $M_{ILL}$ cv. Seokwang and cv. Housemomotaro) seeds were irradiated with the doses of $1{\sim}20$ Gy from $^{60}Co$ $\gamma$-ray source to investigate the effect of the low dose $\gamma$-ray radiation on the early growth and resistance to subsequent high dose of radiation. Germination rate of seeds irradiated with low dose $\gamma$-ray was enhanced in Seokwang cultivar but not in Housemomotaro cultivar. Seedling height increased in 4 Gy and 8 Gy irradiation group of both cultivars. Plant height of Seokwang cultivar was depressed in low dose irradiation group but fresh weight was increased in 2 Gy and 4 Gy irradiation group. In Housemomotaro cultivar, plant height increased in 12 Gy and 20 Gy irradiation group and fresh weight increased in 4 Gy and 20 Gy irradiation group. Growth inhibition of tomato plants by high dose radiation was noticeably reduced by pre-irradiation of low dose radiation. Resistance to subsequent high dose of radiation was enhanced in 2 Gy and 8 Gy Irradiation group of Seokwang cultivar and in 2 Gy and 12 Gy irradiation group of Housemomotaro cultivar.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.257-261
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• 1999

Effect of low dose gamma radiation on the growth of groundnut (Arachis hypognea L.) were investigated with respect to germination rate, seedling development and yield. Seeds of “Palpal” cultivar were irradiated with 0.5~20 Gy of ${\gamma}$ radiation in order to determine the hermetic effect of low dose radiation. The germination rate of ${\gamma}$-ray irradiation group was lower than that of the control but the seedling height of groundnut grown from seeds irradiated with low dose ${\gamma}$-ray was slightly higher than that of the control. The number of pod and kernels, and the seed yield increased by 27%, 17% and 19 %, respectively, in the 12.0 Gy irradiation group compared to that in the control group. The 100 seed weight was 87.2 g in the 4.0 Gy irradiation group, which was 11% heavier than 78.3 g in the control group. Low dose radiation showed an enhancement effects on the growth and yield components of groundnut.

• Journal of Radiation Industry
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• v.17 no.4
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• pp.509-518
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• 2023

The Kori Unit 1 nuclear power plant, which is planned to be dismantled after permanent shutdown, is expected to generate a large amount of various types of radioactive waste during the dismantling process. For the disposal of Very-low-level waste, which is expected to account for the largest amount of generation, the Korea Radioactive waste Agency (KORAD) is in the process of detailed design to build a 3-phase landfill disposal facility in Gyeongju. In addition, a large container is being developed to efficiently dispose of metal and concrete waste, which are mainly generated as Very low-level waste of decommissioning. In this study, based on the design characteristics of the 3-phase landfill disposal facility and the large container under development, radiation exposure dose evaluation was performed considering the normal and accident scenarios of radiation workers during operation. The direct exposure dose evaluation of workers during normal operation was performed using the MCNP computer program, and the internal and external exposure dose evaluation due to damage to the decommissioning waste package during a drop accident was performed based on the evaluation method of ICRP. For the assumed scenario, the exposure dose of worker was calculated to determine whether the exposure dose standards in the domestic nuclear safety act were satisfied. As a result of the evaluation, it was confirmed that the result was quite low, and the result that satisfied the standard limit was confirmed, and the radiational disposal suitability for the 3-phase landfill disposal facility of the large container for dismantled radioactive waste, which is currently under development, was confirmed.

• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.237-242
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• 2003

Single cell gel electrophoresis (SCGE) was used to the experiment with the variation on the amount of smoking and low dose radiation exposure to find how much the Lymphocyte DNA was damaged, and especially for whom smoke a lot(about 20 or more than 20 cigarettes a day) it was found to be highly damaged. While, the damage of 'not more than 20 cigarettes a day' was found to be not so much significant as like for whom smoke about or more than 20 cigarettes a day And, according to the different amount of the radiation exposure, the Lymphocyte DNA was found to be considerably damaged for 0-13m Sv (P<0.01), it was not able to prove the relationship between the DNA damage and the radiation exposure.

• Journal of Radiation Protection and Research
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• v.34 no.2
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• pp.77-81
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• 2009

An Area Radiation Monitoring System (ARMS) ionization chamber, which had an 11.8 L active volume, was fabricated and performance-tested at KAERI. Low leakage currents, linearities at low and high dose rates were achieved from performance tests. The correlation coefficients between the ionization currents and the dose rates are 1 at high dose rate and 0.99 at low dose rate. In this study, an integration-type ARMS ionization chamber was tested over a year for an evaluation of its long-term stability at a radioisotope (RI) repository of the Young-gwang nuclear power plant. The standard deviation of dose rate of 1 day data and over a 100-days mean value were 6.2 $\mu$R/h and 2.9 $\mu$R/h, respectively. The fabricated ARMS ionization chamber showed stable performance from the results of the long-term tests. Design and performance characteristics of the fabricated ionization chamber for the ARMS from performance-tests are also addressed.