• Nuclear Engineering and Technology
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• v.17 no.4
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• pp.267-278
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• 1985

Some kinds of methods have been applied to regulate the exposure doses by the radioactive effluents from nuclear power plants. The essential one is primary dose equivalent limit recommended by the ICRP. When the primary limit cannot be applied directly for regulation, there have been dose equivalent index in case of external exposure, or maximum permissible concentration, annual limit on intake, derived air concentration and maximum permissible body burden in case of internal exposure. But the derived limit is required from the viewpoint of discharge, for those values are inadequate to control discharge rate directly. This study was carried out to derive the release limit for the Wolsung nuclear power plant by the concentration factor method. This method is based on the assumption of steady state transfer between environment compartments.

• The Journal of Internal Korean Medicine
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• v.43 no.4
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• pp.503-513
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• 2022

Objectives: The antitussive, expectorant, and anti-inflammatory effects of Mahwangyounpae-tang (MHYPT) aqueous extracts were observed in appropriate animal models of various respiratory disorders. Methods: MHYPT aqueous extracts were orally administered once a day for 11 days at dose levels of 400, 200, and 100 mg/kg. The effect of MHYPT was determined by comparing its antitussive effect with theobromine (TB), its expectorant effect with ambroxol (AM), and its anti-inflammatory effect with dexamethasone (DEXA). Results: MHYPT aqueous extracts (400 mg/kg) showed favorable antitussive effects comparable to those of TB (50 mg/kg) in the NH₄OH-exposure coughing mouse model and expectorant effects comparable to those of AM (250 mg/kg) in the phenol red-secretion mouse model, but MHYPT (400 mg/kg) showed less anti-inflammatory activity compared to DEXA (1 mg/kg) in the xylene-induced acute inflammatory mouse ear model under the experimental conditions used. Conclusion: MHYPT aqueous extracts administered at dosage levels of 400, 200, and 100 mg/kg induced dose-dependent and favorable antitussive, expectorant, and anti-inflammatory activities that occurred by simultaneous modulation of the activity of mast cells and respiratory mucous production under the experimental conditions used in this study.

• Biomedical Science Letters
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• v.11 no.2
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• pp.143-152
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• 2005

To investigate the exposure effect of polycyclic aromatic hydrocarbons (PAHs), we analyzed the relationship between urinary 8-hydroxydeoxyguanosine (8-OHdG) concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. We measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and urinary 8-OHdG as an effective dose of oxidative DNA damage. There was significant correlation between the urinary concentration of l-OHP and the environmental concentration of PAHs, pyrene, urinary cotinine, AST, and GGT. The mean of urinary 8-OHdG was $17.07\pm1.706{\mu}g/g$ creatinine in workers exposed to airborne PAHs. There was significant correlation between the urinary concentration of 8-0HdG and the airborne concentration of PAHs. From the results of stepwise multiple regression analysis about 8-OHdG, significant independents was total PAHs. In this study, there were significant correlation between the urinary concentration of 8-OHdG and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking and biomarkers of liver function test.

• Journal of radiological science and technology
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• v.28 no.2
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• pp.117-122
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• 2005

According to the Para. 5 of Art 2 of the Korean Nuclear Safety Regulations, which was revised in 1999, internal dose assessment as well as external one should be performed by law for employees at a nuclear power plant from 2003, and their estimate errors should also be within 50%. Thus, more accurate internal dosimetry becomes important. Corresponding to such regulation revision, we are developing a more accurate thyroid-uptake internal dosimetric system and have developed a Monte Carlo simulation code, the so-called CALEFF, to calculate the detection efficiency of the dosimetric system. In this paper, we calculated detection efficiencies with various test conditions by using the CALEFF code and discussed their characteristics. We may use the detection efficiency calculated by the code in calibrating the thyroid internal dose from measured data.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1757-1762
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• 2023

Radiological hazards from external exposure of naturally occurring radioactive materials (NORM) scales residues, generated during the extraction process of oil and gas production in southern Algeria, are evaluated. The activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were measured using high-purity gamma-ray spectrometry (GeHP). Mean activity concentration of ²²⁶Ra, ²³²Th and ⁴⁰K, found in scale samples are 4082 ± 41, 1060 ± 38 and 568 ± 36 Bq kg^-1, respectively. Radiological hazard parameters, such as radium equivalent (Ra_eq), external and internal hazard indices (H_ex, H_in), and gamma index (I_γ) are also evaluated. All hazard parameter values were greater than the permissible and recommended limits and the average annual effective dose value exceeded the dose constraint (0.3 mSv y^-1). However, for occasionally exposed workers, the dose rate of 0.65 ± 0.02 mSv y^-1 is lower than recommended limit of 1 mSv y^-1 for public.

• Journal of Radiation Protection and Research
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• v.7 no.1
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• pp.1-10
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• 1982

For the purpose of establishment of Reference Korean and estimation of internal and external exposure doses in the Reference Korean, we have surveyed reference values for Koreans, such as physical standards including height, weight and body surface area, food consumption rate of daily intake of radioactive substances and exposure dose from natural radiation. The results obtained are as follows: 1) The age group of the Reference Korean ranged from 20 to 30 years old in both sexes. The height, weight and surface area of the body of the Reference Korean are 167cm, 61kg and $1.67m^2$ in male and 155cm, 51kg and $1.51m^2$, respectively in female. 2) The food consumption of the Korean is 812.8g (669.6g of vegetable food and 143.2g of animal food) per capita per day. 3) Koreans are taken about 1,200 pCi of radioactive substances(${\beta}$-ray) per capita per day. 4) The external and internal radiation exposure doses of the Korean are estimated to be 127 mrem and 8 mrem per year, respectively. However, it is believed that these values will be modified upon the addition of data collection.

• Journal of radiological science and technology
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• v.44 no.3
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• pp.247-252
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• 2021

As the number of single-person households increases, the consumption of bottled water is increasing. In addition, as the public's interest in radioactivity increases, interest in the field of living radioactivity is also increasing. Since drinking water is an essential element in our daily life, it must be safe from radioactivity. In this study, gamma radiation of drinking spring water was measured and internal exposure dose evaluation was performed to determine its harmfulness. K-40 and uranium-based radioactivity analysis was performed through a high-purity germanium detector, and as a result, drinking water was detected somewhat higher than that of mixing water. Since there is no regulation on the natural radioactivity concentration in Korea, it was compared with the U.S. Environmental Protection Agency Drinking Water Regulations and World Health Organization standard. As a result, there were some items that exceeded standards. Internal exposure was evaluated according to the effective dose formula of ICRP 119. As the result was derived that a maximum of 1.17 mSv per year could be received. This result means that the dose limit for the general public may be exceeded, and it was judged that it is necessary to set an appropriate standard value and present a recommendation value through continuous monitoring in the future.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.84-89
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• 2023

Background: Food consumption is one of the most important routes for radionuclide intake for the public; therefore, there is the need to have a comprehensive understanding of the amount of radioactivity in food products. Consumption of radionuclide-contaminated food could increase potential health risks associated with exposure to radiation such as cancers. The present study aims to determine radioactivity levels in some food products (milk, rice, sugar, and wheat flour) consumed in Mali and to evaluate the radiological effect on the public health from these radionuclides. Materials and Methods: The health impact due to ingestion of radionuclides from these foods was evaluated by the determination of activity concentration of radionuclides ²³⁸U, ²³²Th, ⁴⁰K, and ¹³⁷Cs using gamma spectrometry system with high-purity germanium detector and radiological hazards index in 16 samples collected in some markets, mall, and shops of Bamako-Mali. Results and Discussion: The average activity concentrations were 9.8±0.6 Bq/kg for ²³⁸U, 8.7±0.5 Bq/kg for ²³²Th, 162.9±7.9 Bq/kg for ⁴⁰K, and 0.0035±0.0005 Bq/kg for ¹³⁷Cs. The mean values of radiological hazard parameters such as annual committed effective dose, internal hazard index, and risk assessment from this work were within the dose criteria limits given by international organizations (International Commission on Radiological Protection and United Nations Scientific Committee on the Effects of Atomic Radiation) and national standards. Conclusion: The results show low public exposure to radioactivity and associated radiological impact on public health. Nevertheless, this study stipulates vital data for future research and regulatory authorities in Mali.

• Environmental Analysis Health and Toxicology
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• v.22 no.1 s.56
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• pp.1-8
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• 2007

Biological monitoring, analyses of internal dose for exposure to toxicants, has been thought as one of the belt approaches for risk assessment. As the amount detected in human samples is generally very low, typically in the parts-per-bilion (ppb) or parts-per-trillion (ppt) range, analytic technologies such at HPLC, GC/MS, LC/MS, and LC/MS/MS have been continuously developed. In addition, route specific and sensitive exposure biomarkers have been developed for proper biological monitoring. PBPK modeling, particularly reverse dosimetry, has been emphasized as an useful method via interpretation of biological monitoring results for regulation of toxicants. Thus, this review is focused on the use of PBPK dosimetry models for toxicology research and risk assessment in Korea.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4659-4663
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• 2023

The use of iodine S values derived using the International Commission Radiological Protection (ICRP) phantoms may introduce significant bias in internal dosimetry for Koreans due to anatomical variability. In the current study, we produced an extensive dataset of Korean S values for selected five iodine radioisotopes (I-125, I-129, I131, I-133, and I-134) for use in radiation protection. To calculate S values, we implemented Monte Carlo simulations using the Mesh-type Reference Korean Phantoms (MRKPs), developed in a high-quality/fidelity mesh format. Noticeable differences were observed in S value comparisons between the Korean and ICRP reference phantoms with ratios (Korean/ICRP) widely ranging from 0.16 to 6.2. The majority of S value ratios were lower than the unity in Korean phantoms (interquartile range = 0.47-1.28; mean = 0.96; median = 0.69). The S values provided in the current study will be extensively utilized in iodine internal dosimetry for Koreans.