• Proceedings of the Korean Society of Toxicology Conference
• /
• 2001.10a
• /
• pp.178-178
• /
• 2001

The interaction of extremely low frequency magnetic field (ELF-MF) on the frequency of micronuclei (MN) induced by benzo(a)pyrene (BP) in human lymphocytes was examined. A 60 Hz ELF-MF of 0.8 mT field strength was applied for 24 hours either alone or with the tumour initiator, BP. The frequency of MN induced by BP increased in a dose-dependent manner.(omitted)

• International Journal of Oral Biology
• /
• v.35 no.4
• /
• pp.137-144
• /
• 2010

To evaluate the biohazard properties of an extremely low frequency electromagnetic field (ELF-EMF), we explored the physical properties of the ELF-EMF that generates the electric current induction in the secondary coil from the chamber of a primary solenoid coil. We subsequently explored the biological effects of a strong alternating electromagnetic field (EMF), ranging from 730-960 Gauss, on the mouse testis. Mice were exposed to an alternating EMF field induced by a rectangular electric current at 1, 7, 20, 40, and 80 Hertz, for 1, 3, 5, and 7 hours. The mouse testes were examined for proliferative activity and apoptosis using the in situ terminal deoxynucleotidyl transferase (TdT) method and by immunostaining of proliferating cell nuclear antigen (PCNA), respectively. We found that the electric currentm induction increased in the 6-8 Hertz range, and that exposure to an ELF-EMF induced the apoptosis of mouse spermatocytes. In situ TdT staining was found to be most prominent in 7 Hertz group, and gradually reduced in the 20, 40, and 80 Hertz groups. These data suggest that a strong EMF can induce reproductive cell death within a short time, and the harmful effects of the EMF are maximal at low frequency alternating EMFs.

• 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.

• Journal of Digital Convergence
• /
• v.19 no.5
• /
• pp.207-214
• /
• 2021

Humans are environmentally exposed to various electromagnetic fields, but the evaluation of the harmfulness of electromagnetic field and the development of a system therefor are still incomplete. We aimed to develop a system for evaluating biohazard against electromagnetic fields, and to determine biohazard through the system. An extremely-low frequency magnetic field generator was designed and manufactured, and the output reliability of the device was verified. Using this device, the effect on the formation of cellular stress-granules and the cell cycle progression of cells exposed to high magnetic fields of 6 mT and 60 Hz was confirmed. As a result, exposure to high magnetic fields of 6 hr, 12 hr and 36 hr did not affect the formation of cell stress-induced granules and the cell division cycle. These results are an important basis for the determination of biohazard to the extremely-low frequency high magnetic field.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.26 no.1
• /
• pp.1-10
• /
• 2016

Objectives: The aim of this study is to review the results of exposure to chemicals and to extremely low frequency(ELF) magnetic fields generated in wafer fabrication operations in the semiconductor industry. Methods: Exposure assessment studies of silicon wafer fab operations in the semiconductor industry were collected through an extensive literature review of articles reported until the end of 2015. The key words used in the literature search were "semiconductor industry", "wafer fab", "silicon wafer", and "clean room," both singly and in combination. Literature reporting on airborne chemicals and extremely low frequency(ELF) magnetic fields were collected and reviewed. Results and Conclusions: Major airborne hazardous agents assessed were several organic solvents and ethylene glycol ethers from Photolithography, arsenic from ion implantation and extremely low frequency magnetic fields from the overall fabrication processes. Most exposures to chemicals reported were found to be far below permissible exposure limits(PEL) (10% < PEL). Most of these results were from operators who handled processes in a well-controlled environment. In conclusion, we found a lack of results on exposure to hazardous agents, including chemicals and radiation, which are insufficient for use in the estimation of past exposure. The results we reviewed should be applied with great caution to associate chronic health effects.

• Archives of Pharmacal Research
• /
• v.28 no.5
• /
• pp.587-591
• /
• 2005

The effect of extremely low frequency (ELF,60Hz) magnetic fields (MFs) on convulsions was investigated in rats. We determined the onset arid duration of convulsions induced by bicuculline alone or by co-exposure to MFs and bicuculline. In addition, we measured the GABA concentrations in the rat brains using HPLC-ECD. MFs strengthened the convulsion induced by bicuculline (0.3, 1, and 3${\mu}g$, I.c.v.), with a shortening of the onset time, but lengthening of the duration time. Co-exposure to MFs and bicuculline decreased the GABA levels in the cortex, hippocampus and hypothalamus, whereas MFs alone reduced the level of GABA only in the hippocampus. These results suggest that the exposure to MFs may modulate bicuculline-induced convulsions due to GABA neurotransmissions in rat brains.

• KEPCO Journal on Electric Power and Energy
• /
• v.1 no.1
• /
• pp.15-20
• /
• 2015

To examine the magnetic shielding effect for carbon-based materials at extremely low frequencies (60 Hz), two types of carbon black (Super-P and Denka Black) and a natural graphite (HC-198) were mixed into organic binder at 10 wt.% to produce a coating solution, and a powder coating with varying thickness was applied on an aluminum disk measuring 88 mm in radius. A device was developed to measure the sheielding effect at extremely low frequencies. A closed circuit was achieved by connecting a transformer and a resistor. The applied voltage was fixed at 65 V, and the magnetic field was measured to being the range of 4.95~5.10 mG. Depending on the thickness of the coating layer, the magnetic field showed a decreasing trend. The maximum decrease in the magnetic field of 38.3% was measured when natural graphite was coated with specimens averaging $455{\mu}m$. This study confirmed that carbon-based materials enable magnetic shielding at extremely low frequencies, and that the magnetic shielding effect can be enhanced by varying the coating thickness.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.18 no.5 s.120
• /
• pp.553-562
• /
• 2007

In this paper, we designed and implemented the system for telemetering ELF(Extremely Low Frequency) magnetic field intensity. The magnetic field measurement system used a 3-axis magnetic field sensor to measure the magnetic field with isotropy and the equalizer to compensate the frequency characteristic in band. By multiplexing three output signals of the magnetic field sensor in time domain, we got the uniform gain and frequency characteristic among three axes. This system was designed that the magnetic field measurement level range was $0.01{\sim}10.0\;uT$ and the measurement frequency band was $40{\sim}180\;Hz$. The control system would access to the magnetic field measurement system with RF and the maximum access distance was 1.0 km. We confirmed that the measurement level error of the fabricated system was within 5 %. The fabricated system was installed to a golf practice range where a high voltage power transmission line was crossed.

• Defense and Technology
• /
• no.2 s.38
• /
• pp.68-71
• /
• 1982

• Proceedings of the Korean Magnestics Society Conference
• /
• 2000.09a
• /
• pp.482-483
• /
• 2000