• Journal of Radiation Protection and Research
• /
• v.27 no.2
• /
• pp.81-87
• /
• 2002

The interaction of low density extremely low frequency magnetic field (ELF MF) in the frequency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) mutation induced by bleomycin and on the frequency of sister chromatid exchanges (SCEs) induced by 1,2,4-benzenetriol(BT) was demonstrated. CHO cells pretreated with bleomycin or 1,2,4-benzenetriol were exposed for 24hrs to a sinusoidal 0.8mT magnetic field at 60Hz. Frequency of HPRT mutation and SCEs were determined. ELF MF exposure led to a two-fold increase of the frequency of HPRT mutation induced by bleomycin. No increase of mutation frequency was observed by ELF MF alone ELF MF also increased the frequency of SCEs induced by BT while no Increase of SCE frequencies were observed by ELF MF alone. These results suggest that low density ELF MF field would art as an enhancer rather than as an initiator of mutagenic effects in CHO cell.

• Proceedings of the KIEE Conference
• /
• 2001.07a
• /
• pp.407-409
• /
• 2001

상용주파 자계와 인체의 건강에 대해서 과학적인 해명 목적으로 Specific Pathegen Free Room을 제작하였다. 환경 실험실의 설치조건 중 자계 노출장 치간의 Stray Field의 영향이 중요하므로 SPF Room을 배치하는 데 있어 각 자계노출장치의 Stray Field로 인한 노출장치의 자계 균일도를 예측 계산하고 그 결과를 바탕으로 최적 배치를 구하였으며 실제 자계 균일도를 측정한 결과 목표한 바와 같이 2%이내임을 확인하였다.

• Proceedings of the PSK Conference
• /
• 2000.10a
• /
• pp.151.2-152
• /
• 2000

• Proceedings of the PSK Conference
• /
• 2001.10a
• /
• pp.195.2-195.2
• /
• 2001

• Current Optics and Photonics
• /
• v.7 no.2
• /
• pp.119-126
• /
• 2023

The vibratory and rotational levels of many biological macromolecules lie in the terahertz (THz) band, which means that THz techniques can be used to identify and detect them. Moreover, since the biological activity of most biomolecules only becomes apparent in aqueous solution, we use microfluidic technology to study the biological properties of these biomolecules. THz time-domain spectroscopy was used to study the THz absorption characteristics of graphene oxide (GO) aqueous solution at different concentrations and different exposure times in fixed electric or magnetic fields. The results show that the spectral characteristics of the GO solution varied with the concentration: as the concentration increased, the THz absorption decreased. The results also show that after placing the solution in an external electric field, the absorption of THz first increased and then decreased. When the solution was placed in a magnetic field, the THz absorption increased with the increase in standing time. In this paper, these results are explained based on considerations of what is occurring at the molecular scale. The results of this study provide technical support for the further study of GO and will assist with its improved application in various fields.

• Journal of the Korean Society of Safety
• /
• v.36 no.5
• /
• pp.10-17
• /
• 2021

The controversy over the risk of the human body being affected by electromagnetic fields emitted from 60 Hz power lines continues without end. There are currently no new studies or research progress being made in this direction that is notable, and the number of civil complaints is gradually increasing. The problem is that each study produces different results, among which the effect of exposure to magnetic fields on childhood leukemia is a major one. In Korea, an electrician who was maintaining a 22.9 kV power line died of leukemia, which has recently been recognized as an occupational disease. Methods to reduce magnetic fields from power lines include shielding with wire loops, incorporating split phases and compaction techniques, installing underground power lines, converting to high-voltage direct current (HVDC), and increasing the ground clearance of transmission towers. Depending on whether a separate power supply is needed or not, there are two types of wire loops: passive loop and active loop. Magnetic field reduction is currently done through underground power lines; however, the disadvantage of this process is high construction costs. Installing passive loops, with relatively low construction costs, leads to lower magnetic field reduction rates than installing underground cables and a weakness to not solving the landscape problem. This methodological study aims at designing methods and reducing the effects of 2-wire set loops-the simplest and most practical. Since the method proposed in this study has been designed after analyzing the distribution of complex electromagnetic fields near the expected loop installation location, a practical design can be implemented without the need for any difficult optimization programming.

• Biomolecules & Therapeutics
• /
• v.22 no.6
• /
• pp.570-576
• /
• 2014

Studies have demonstrated that electromagnetic waves, as the one of the most important physical factors, may alter cognitive and non-cognitive behaviors, depending on the frequency and energy. Moreover, non-ionizing radiation of low energy waves e.g. very low frequency waves could alter this phenomenon via alterations in neurotransmitters and neurohormones. In this study, short, medium, and long-term exposure to the extremely low frequency electromagnetic field (ELF-EMF) (1 and 5 Hz radiation) on behavioral, hormonal, and metabolic changes in male Wistar rats (250 g) were studied. In addition, changes in plasma concentrations for two main stress hormones, noradrenaline and adrenocorticotropic hormone (ACTH) were evaluated. ELF-EMF exposure did not alter body weight, and food and water intake. Plasma glucose level was increased and decreased in the groups which exposed to the 5 and 1Hz wave, respectively. Plasma ACTH concentration increased in both using frequencies, whereas noradrenaline concentration showed overall reduction. At last, numbers of rearing, sniffing, locomotor activity was increased in group receiving 5 Hz wave over the time. In conclusions, these data showed that the effects of 1 and 5 Hz on the hormonal, metabolic and stress-like behaviors may be different. Moreover, the influence of waves on stress system is depending on time of exposure.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.3
• /
• pp.613-618
• /
• 2019

EMF (Electromagnetic Field) is a valuable resource for living in a knowledge-based information society. The EMF is used in home appliances that make our lives easy and convenient, and in telecommunication devices such as mobile phones, personal computers, medical devices and broadcasting towers. However, the biological hazards associated with EMF exposure are also increasing in signal from telecommunication devices. Studies of the effects of EMF exposure on humans have been conducted for a long time, but it has not yet been demonstrated whether the EMF effect is harmful. In this paper, we examine the electromagnetic field emitted from various electronic devices around living and its effect.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.3
• /
• pp.398-402
• /
• 2007

Abstract Female mice post weaning were exposed to 20 kHz sawtooth electric and magnetic fields (EMF) with $6.25{\mu}T$ peak intensity for 6 weeks. Estrous cycles were checked using vaginal smears over the last 10 days of the experimental period. The vaginal smears from EMF-exposed mice revealed an increase in the frequency of one or two phases persisting. The number of estrous cycles less than 1 was more in the EMF-exposed group than in the sham control group. Furthermore, in the EMF-exposed group, the duration of proestrous and metestrous stages of the estrous cycle was significantly increased compared with the control group. In conclusion, our results suggest that exposure to 20 kHz sawtooth EMF may affect normal cycling of the estrous cycle by disrupting the female reproductive endocrine physiology. We should not disregard the possible adverse reproductive effect of the 20 kHz sawtooth EMF generated under the occupational exposure situation in females.

• Journal of Environmental Health Sciences
• /
• v.34 no.1
• /
• pp.27-33
• /
• 2008

In order to evaluate the magnetic field (MF) exposure level in residential areas near high voltage power lines, this research measured MF levels at 120 sites near high voltage transmission lines in the Busan region, Gwangju region, Daegu region and Changwon region from July to December, 2005, and compared and analyzed the efficiencies by measuring and applying the MF emission levels of underground cables and high voltage transmission lines. As a result of the investigation of the MF exposure level by the building usage, the average MF level of 17 locations at schools was $2.44{\pm}2.45mG;$ that of 10 locations at hospitals $6.21{\pm}12.39mG;$that of 76 locations at apartments $2.55{\pm}2.98mG;$ and that at kindergartens and infant houses $3.32{\pm}4.21mG$. MF exposure was analysed as a function of distance from the source and the MF levels directly below a source were $5.15{\pm}8.72mG$, those within 30 m were $3.10{\pm}3.32mG$, while those within 50 m were $2.45{\pm}2.38mG$, and within 100 m were $0.71{\pm}0.93mG$. In order to determine the difference of MF levels by the actual distance from high voltage transmission line within the same building, the evaluation of the floor position and the MF level has shown that the MF levels were highest in the order of roof, 4th floor, 3rd floor, 2nd floor and 1st floor. Comparison of MF emission intensity of underground cables and high voltage transmission lines, has shown that underground cables have an 86-94% of reduction ratio in MF compared to high voltage transmission lines, thus demonstrating higher efficiency.