• Title/Summary/Keyword: Field exposure

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BIOLOGICAL HUMAN MONITORING OF CARCINOGEN EXPOSURE: A NEW STRATEGY IN CANCER PREVENTION

  • Lee, Byung-Mu
    • Toxicological Research
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    • v.6 no.1
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    • pp.63-73
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    • 1990
  • Human exposure to environmental carcinogens can be detected by a number of methods including immunoassay, $^{32}P-postlabeling$ assay, and fluorescence technique. These assays have been applied to measure biological markers of carcinogen-adducts formed with macromolecules such as DNA, RNA and protein. In an attempt to investigate causal relationships between carcinogen exposure and tumor formation, specific carcinogen-adducts have been quantitated from human tissues and body fluids of cancer patients, occupational workers heavily exposed to certain carcinogens, smokers and controls. Carcinogens studied for biological human monitoring include benzo(a)pyrene, aflatoxin B1, UV light, ethylene oxide, 8-methoxypsoralen, 4-aminobiphenyl, vinyl choride, N-nitrosamine, cisplatin and other chemotherapeutic agents. Relevance of human monitoring for cancer research, progress in this field, methods to detect carcinogen-adducts are reviewed here. It is hoped that these approaches will be used for the risk assessment of carcinogen exposure, cancer etiology study and cancer prevention in humans.

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BIOLOGICAL HUMAN MONITORING OF CARCINOGEN EXPOSURE: A NEW STRATEGY IN CANCER PREVENTION

  • Lee, Byung-Mu
    • Toxicological Research
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    • v.6 no.1
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    • pp.61-61
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    • 1990
  • Human exposure to environmental carcinogens can be detected by a number of methods including immunoassay, $^{32}P$-postlabeling assay, and fluorescence technique. These assays have been applied to measure biological markers of carcinogen-adducts formed with macromolecules such as DNA, RNA and protein. In an attempt to investigate causal relation ships between carcinogen exposure and tumor formation, specific carcinogen-adducts have been quantitated from human tissues and body fluids of cancer patients, occupational workers heavily exposed to certain carcinogens, smokers and controls. Carcinogens studied for biological human monitoring include benzo(a)pyrene, aflatoxin B1, UV light, ethylene oxide, 8-methoxypsoralen, 4-aminobiphenyl, vinyl chloride, N-nitrosamine, cisplatin and other chemotherapeutic agents. Relevance of human monitoring for cancer research, progress in this field, methods to detect carcinogen-adducts are reviewed here. It is hoped that these approaches will be used for the risk assessment of carcinogen exposure, cancer etiology study and cancer prevention in humans.

Study on the Development and Field Application of Glossing Exposure Concrete (광택노출콘크리트의 개발 및 실용화 연구)

  • 하재담;정태웅;이현희;공양식;강창운;정일모
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.04a
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    • pp.249-254
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    • 1998
  • Recently, high quality architectural concrete, i.e., appearance of natural stone and a marbling effect, is needed, to achieve high quality glassy reflective surface for outer wall of the building. In this study to achieve above characteristics of the "glossing exposure concrete" we developed a form practice and the best mix proportion and derived the optimistic removal time of form to bring out the durable glassy reflective surface and durable concrete. Hereby with the "glossing exposure concrete" obtained we applicate for first time, to Electronics and Telecommunications Research Institute situated on Taedok Science Town and it will be the beginning of the construction of "glossing exposure concrete" in this country.oncrete" in this country.ntry.

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Exposure limits of Magnetic fields of High Voltage Transmission lines for Evaluation of Environmental Impact (고압선로 환경영향평가의 자기장 노출범위설정에 관한 연구)

  • Jeon, In-Soo
    • Journal of Environmental Impact Assessment
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    • v.13 no.5
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    • pp.243-250
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    • 2004
  • Recently, concerns about health risks exposed to electromagnetic fields have been brought in the safety of electric power lines. A number of governmental and international organizations have advised to avoid the magnetic field exposure to the schools and residential areas. Some epidemiologic studies showed that electromagnetic fields should not exceed the exposure limits of 2-3mG to the people living near high-voltage transmission lines. In this study, the principles, ranges and survey methods of the assessment for powerfrequency electromagnetic fields were reviewed from the relevant research papers and documents. The ranges of electromagnetic fields were determined from 50m to 100m and have been defined according to the properties of each electric power lines and a new methodology was suggested in this study. It would be necessary to develop and improve specific assessment methods for various high-voltage transmission lines projects.

Correlation Between Exposure Rate and Quasi-Effective Energy of Natural Radiation in Japan -TLD Application-

  • Nakajima, Toshiyuki
    • Journal of Radiation Protection and Research
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    • v.12 no.1
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    • pp.54-60
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    • 1987
  • The quasi-exposure rate and the quasi-effective energy of the natural radiation in the field at 47 monitoring points around nuclear power plants have been studied with the pair filter thermoluminescence dosimeter system. The results of the six years observation showed that the relationship between the quasi-exposure rate $X_q$, and quasi-effective energy $E_q$ can be represented as a hyperbolic function: $X_q=A+C/(E_q-B)$, where the constants A and B correspond to the quasi-exposure rate of cosmic-rays and the minimum quasi-effective energy of natural radiation, respectively. Furthermore, the constant A is in close agreement with the values obtained by using ionization chambers and scintillation detectors. The constant B is approximately 0.68 MeV, closely corresponding to the mean energy of the photons emitted from natural uranium.

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Standard Trends of Human Exposure to Electromagnetic Waves (전자파 인체 노출 표준 동향)

  • Jeon, S.B.
    • Electronics and Telecommunications Trends
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    • v.34 no.3
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    • pp.86-92
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    • 2019
  • New products and services, such as 5G and wireless power transmission equipment, have recently brought about changes in the field of electromagnetic technology. There is a need for the evaluation and measurement of the health effects of such technology. To address this need, the development of international standards related to human exposure to electromagnetic waves of these new technologies are currently being discussed. This article briefly introduces the International Standard Organization standards for human exposure to electromagnetic waves, and focuses on the major standard trends for SAR measurement techniques that employ vector probes, wireless power transfer, and 5G base station measurement.

Study on the Exposure Field of Head and Neck with Measurement of X-ray dose Distribution for Dental Panoramic X-ray System (치과 파노라마 장치의 X선 공간선량분포 측정을 통한 두경부 피폭영역 조사에 대한 연구)

  • Oh, Yoonjin;Hong, Girang;Lee, Samyol
    • Journal of the Korean Society of Radiology
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    • v.9 no.1
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    • pp.17-21
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    • 2015
  • Recently, As people's interest in the health of teeth is increased in the medical field changed into aging society, the number of times for the radiological diagnosis is increased. It can be said that the radiation exposure dose of Korean population is increased. It is also growing concern about radiation exposure. Therefore, the basic data for the dental panoramic X-ray system, its investigation and measuring the radiation dose is needed. In this study, we used ALOKA PDM-117 dosimeter and estimated a two-dimensional dose distribution of the dental panoramic X-ray system (VATEC Pax-400). Dose evaluation about the distribution is confirmed from the point of radiation exposure of a patient. Dose distribution of the dental panoramic X-ray system irradiated chin and the facial region to high dose as well as the parts of teeth. It was founded that the eye lens which are sensitive to radiation are exposed to unnecessary radiation, considering the effect of scattered radiation. The results of this study will be used more accurate dose assessment in a variety of object size and location of measuring dose.

Performance Evaluation of Repair Methods for RC structures by Accelerating Test in Combined Deterioration Chamber and Long-Term Field Exposure Test (복합열화촉진실험 및 장기현장폭로실험에 의한 RC구조물 보수공법의 보수성능평가)

  • Kwon Young-Jin;Kim Jae-Hwan;Han Byung-Chan;Jang Seung-Yup
    • Journal of the Korean Society for Railway
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    • v.9 no.4 s.35
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    • pp.349-356
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    • 2006
  • At present, the selecting system and analytic estimation criterion on repair materials and methods of the deteriorated RC structures have not yet been set up in domestic. Under these circumstances, deterioration such as shrinkage crack, corrosion of rebar has been often occurred after repair, and this finally results in too frequent repairs. In this study, three types of repair methods were experimentally investigated by the accelerating test in a combined deterioration chamber and long-term field exposure test. Three types of repair methods applied in this study belong to a group of polymer cement mortar, which is commonly used in repair works. According to the results of this study, durability of repair mortar layers and corrosion properties of recovered rebar could be investigated in short period by the accelerating test in a combined deterioration chamber, which can simulate the condition of repeated high-and-low temperature and repeated dry-and-wet environment, spraying chloride solution and emitting $CO_2$ gas. After 36 month long-term filed exposure test in the coastal area, harmful macro-cracks are observed in the polymer cement mortar layer of some repair methods. These crack are considered to result from drying shrinkage of polymer cement mortar. Also, after 36 month exposure, amount of corrosion area and weight loss of rebar are found to be different according to the types of repair methods.

A Suggestion for Carbonation Prediction Using Domestic Field Survey Data of Carbonation (국내 탄산화 실태자료를 이용한 탄산화 예측식의 제안)

  • Kwon, Seung-Jun;Park, Sang-Sun;Nam, Sang-Hyeok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.11 no.5
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    • pp.81-88
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    • 2007
  • Among deteriorations of concrete due to environmental exposure, carbonation problems of concrete structures have increased in urban and underground structures. But conventional carbonation-prediction equations that were proposed by foreign references, can not be applied directly to the prediction of carbonation for domestic concrete structures. The purpose of this study is to propose a prediction equation of carbonation depth by considering domestic exposure conditions of concrete structures. For the derivation of the equation, conventional carbonation-prediction equations are analyzed. Through considering the relationship between results of prediction equation and those of various domestic field survey data, the so-called correction factors for different domestic exposure condition of concrete structures are derived. Finally, a carbonation-prediction equation of concrete structures under domestic exposure conditions is proposed with consideration for concrete strength in core and correction factors.

Analysis of Worker Exposure Space according to Distribution of Electromagnetic Field of Generator (발전기의 전자기장 분포 특성에 따른 작업자 노출공간 분석)

  • Seong, Minyoung;Kim, Doo-Hyun;Kim, Seungtae
    • Journal of the Korean Society of Safety
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    • v.36 no.4
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    • pp.20-28
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    • 2021
  • With an increase in the commercialization of electricity, and the development of advanced and large electric devices and various wireless radio wave services, concerns over the effects of electromagnetic fields on human health have increased. Accordingly, the World Health Organization encouraged the development of international standards by establishing the 'International Electromagnetic Fields Project' in 1996 based on studies on the harmful effects of electromagnetic fields on the human body. Moreover, the National Institute of Environmental Health Sciences (NIEHS) classified electromagnetic fields as possible carcinogens under Group 2B category, even though they have been found to have a weak correlation with those effects on human health. Mid-to-large-sized electric facilities used at industrial sites mostly adopt a commercial frequency of 60 Hz, and workers handling these facilities are exposed to such extremely low frequency (ELF) fields for a long time. A previous study suggested that exposure to ELF electromagnetic fields with frequency ranges from 0 to 300 Hz, even for a short time, at densities higher than 100 μT may have harmful effects on human body as it affects the activation of nerve cells in the central nervous system by inducing an electric field and current and stimulating muscles and the nervous system in the body. Such studies, however, focused on home appliances used by ordinary people, and research on facilities utilizing high-capacity current and operated by workers at industrial sites is lacking. Therefore, in this study, a 3000 kilowatt generator, which is a high-capacity electric facility employed at industrial sites, was investigated, and the size of the magnetic fields generated during its no-load and high-load operations per distance to produce a map was measured to reveal spots deemed hazardous according to domestic and international exposure standards. The findings of this study is expected to alleviate workers' anxiety about the harmful effects of magnetic fields on their body and to minimize the level of exposure during operations.