• Clinical and Experimental Pediatrics
• /
• 제63권11호
• /
• pp.422-428
• /
• 2020

In today's world, most children are exposed to various manmade electromagnetic fields (EMFs). EMFs are electromagnetic waves less than 300 GHz. A developing child's brain is vulnerable to electromagnetic radiation; thus, their caregivers' concerns about the health effects of EMFs are increasing. EMF exposure is divided into 2 categories: extremely low frequencies (ELFs; 3-3,000 Hz), involving high-voltage transmission lines and in-house wiring; and radiofrequencies (RFs; 30 kHz to 300 GHz), involving mobile phones, smart devices, base stations, WiFi, and 5G technologies. The biological effects of EMFs on humans include stimulation, thermal, and nonthermal, the latter of which is the least known. Among the various health issues related to EMFs, the most important issue is human carcinogenicity. According to the International Agency for Research on Cancer's (IARC's) evaluation of carcinogenic risks to humans, ELFs and RFs were evaluated as possible human carcinogens (Group 2B). However, the World Health Organization's (WHO's) view of EMFs remains undetermined. This article reviews the current knowledge of EMF exposure on humans, specifically children. EMF exposure sources, biological effects, current WHO and IARC opinions on carcinogenicity, and effects of EMF exposures on children will be discussed. As well-controlled EMF experiments in children are nearly impossible, scientific knowledge should be interpreted objectively. Precautionary approaches are recommended for children until the potential health effects of EMF are confirmed.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.181-184
• /
• 2004

There are reports showing that electromagnetic fields (EMFs) emitted at non-thermal levels may be associated with biological alterations in target cells. In this study it is objected to assess the potential influences of EMFs produced by cellular phones on fetal heart rate. Non Stress Test (NST) is a widely used method of fetal monitoring and assessing fetal health and well-being. Sixty volunteers with uncomplicated term pregnancies were studied by a Spacelabs AM-67 Doppler ultrasound monitor. Fetal Heart Rate recordings were obtained while there were no Cellular Phone around for 10 minutes. Afterwards, all patients were exposed to EMFs for 10 minutes. NST was performed while they were holding the CP on stand-by mode and then on dialing mode, each for 5 minutes. The recordings were analyzed with respect to baseline heart rate, accelerations and decelerations. The Wilcoxon matched-pairs signed-ranks test was used to compare these variables. The results indicate that EMFs emitted by CP do not cause any demonstrable effects on baseline FHR, acceleration or deceleration.

• 한국산업보건학회지
• /
• 제8권2호
• /
• pp.264-271
• /
• 1998

A pilot study was undertaken to examine the possible health effects of electromagnetic fields(EMFs). The purpose of this study was to investigate of the EMFs exposures of personal environment, 60Hz magnetic fields. An experimental study was performed for six weeks of January-February 1998 to compare changes in melatonin levels in urine of 20 subjects during their normal sleeping hours and each 20 subjects in occupational and non-occupational group measured personal 24-h continual exposure, using EMDEX II (for 40-800Hz, Enertech Consultant, Inc.). An urine samples were collected 3 times a day(before sleep or around 24:00 ; immediately after wake-up ; around noon) for an week from each subjects and analyzed by radioimmunoassay. This study did not significant difference for the subjective average melatonin levels between occupational and nonoccupational groups exposed to electromagnetic fields. The mean personal exposure levels of occupational group were $0.215{\mu}T$, whereas non-occupational group were $0.18{\mu}T$. Occupational group were exposed more highly while at work. Finally, this study would provide significant data for furture study of exposure assessment of magnetic fields. A large scale study concerning more detailed exposure assessment should provide important information on health risk assessment of MFs. Further study should provide information on the contribution of various sources and the relationship between melatonin and immune system activity.

• Safety and Health at Work
• /
• 제4권3호
• /
• pp.156-159
• /
• 2013

Background: Cardiac pacemakers are known to be susceptible to strong electromagnetic fields (EMFs). This in vivo study investigated occurrence of electromagnetic interference with pacemakers caused by common environmental sources of EMFs. Methods: Eleven volunteers with a pacemaker were exposed to EMFs produced by two mobile phone base stations, an electrically powered commuter train, and an overhead high voltage transmission lines. All the pacemakers were programmed in normal clinically selected settings with bipolar sensing and pacing configurations. Results: None of the pacemakers experienced interference in any of these exposure situations. However, often it is not clear whether or not strong EMFs exist in various work environments, and hence an individual risk assessment is needed. Conclusions: Modern pacemakers are well shielded against external EMFs, and workers with a pacemaker can most often return to their previous work after having a pacemaker implanted. However, an appropriate risk assessment is still necessary after the implantation of a pacemaker, a change of its generator, or major modification of its programming settings.

• 한국환경보건학회지
• /
• 제23권3호
• /
• pp.130-135
• /
• 1997

A pilot study was undertaken to examine the possible health effects of electromagnetic fields (EMFs). An experimental study was performed for two weeks of preexposure, exposure, postexposure period of February-May 1997 to determine changes in melatonin levels in urine of five volunteers before or after exposure to electric mattress during their normal sleeping hours. An urine sample was collected at about 8 a.m. right after getting up from each volunteer. Average melatonin levels seemed to be 1.6 times lower during EMF exposure period for two weeks than the corresponding levels during preexposure period. Mean melatonin levels in postexposure period were lower than the corresponding levels in preexposure period. It suggested that melatonin levels were likely to take more two weeks for recovering the preexposure melatonin level. Further research is underway with regard to EMF exposure effects on melatonin levels between occupational and nonoccupational groups.

• 한국환경보건학회지
• /
• 제40권5호
• /
• pp.376-384
• /
• 2014

Objective: The purpose of this study is to compare the health status of residents who were exposed to sources of extremely low frequency electromagnetic fields (ELF-EMFs) in the living environment and those who were not exposed to such a source of ELF-EMFs through a survey designed to appraise the residents' health levels. Method: Aimed at 251 residents exposed to a source of ELF-EMFs and 278 residents not exposed to a source, the survey was conducted to investigate the health status of the residents on the basis of questionnaire SF-36. Result: The health status scores of residents exposed to ELF-EMFs turned out to be lower than those of their counterparts. In terms of self-reported symptoms related to health and sleep quality, residents exposed to ELF-EMFs were found to have a higher complaint rate of self-reported symptoms such as dizziness, depression, and fatigue. Regarding sleep disorders, residents exposed to ELF-EMFs appeared to have a slightly higher complaint rate of sleep disorders compared to non-exposed residents. Conclusion: If a region is to be exposed to a source of ELF-EMFs, a more proactive policy for reducing such exposure is advised. In addition, it is necessary to better understand problems of residents by emplacing an ELF-EMFs risk information delivery system and building an efficient communication system for voluntary participation during the construction phase.

• 한국전자파학회논문지
• /
• 제9권5호
• /
• pp.687-697
• /
• 1998

최근 국내 전력설비에서 발생하는 전자계에 대한 관심이 증가하고 있지만 이에 대한 정확한 자료 파악은 극히 미미한 실정이다. 본고에서는 송전선로에서 발생하는 전계와 자계의 수준을 알아보기 위하여 전국 1537H의 송전 선로를 대상으로 전계와 자계를 측정하였다. 측정 지점의 전계와 자계 최대치들의 중간값은 각각 0.47 kV /m, 11.6 mG 최고 값은 각각 3.16 kV /m, 125 mG로 나타났으며, 전세계의 전자계 관련 권고치나 기준치에 비해 낮은 값임을 알 수 있었다. 아울러 몇 가지 경우에 대하여 가전제품에서 발생하는 자계와 일일 자계 노출량올 측정 하였고 이를 송전선로의 자계 크기와 비교하였다.

• Journal of Microbiology and Biotechnology
• /
• 제11권5호
• /
• pp.749-755
• /
• 2001

High Electromagnetic Field (EMF) with an intensity of 1 mT (Tesla) inhibited the growth of both human normal lung and immune T cell down to $20-30\%$, compared to that of an unexposed case. The human T-cells, Jurkat, were more severely affected by EMF than the human lung cells, which showed a relatively slow cell growth and substantial releas of $Ca^+2$ (3.5 times higher than the human T-cells). However, the growth of hepatoma carcinoma, Hep3B, was enhanced by twice that of an unexposed case. The EMF intensity and exposure time did not affect the growth of the cancer cells very much, while it significantly affected the growth of normal cells. Accordingly, it is possible that EMFs may play a role in the initiation of cancer. The EMFs disturbed the signal transduction and membrane systems, such that a five times higher amount of PKC-${\alpha}$ was released from the cell membrane than in the control. Extended exposure to EMFs, for more than 48 hours, also led to 1 $90\%$ necrotic death pattern from apoptotic cell death. Finally, EMF at an intensity of 1mT with a 24-T exposure promoted the differentiation of HL-60 cells to monocytes/macrophages, possibly causing potential acute leukemia.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1997년도 춘계학술대회
• /
• pp.299-302
• /
• 1997

Recently, many people are interested in the electromagnetic fields(EMF), so we measured the strength of electromagnetic fields in the carriages of national railways and subways. We also measured on the platforms of national railways and subways. The strength of EMFs on the platforms of national railways was stronger than that of subway's platforms. EMF measured on the platform during railway carriage's arriving and leaving was stronger than that without carriages. The strength of the magnetic fields in the carriages of national railways was measured stronger than that of subway's carriage while national railway is run by AC while subway is run by DC. Also The strength of the subway line 8 were measured stronger two to three times than others.

• 한국전자파학회논문지
• /
• 제25권9호
• /
• pp.879-885
• /
• 2014

논문에서는 전자파(EMFs) 측정을 위한 광대역 3축 등방성 안테나를 설계 및 제작하였다. 제안된 3축 안테나의 각축에 따른 개별 안테나는 등방성 특성을 가지며, 임의의 안테나 축을 선택하기 위하여 RF 스위치를 사용하였다. 또한, 안테나의 이득 개선 및 잡음성분을 억제하기 위하여 각 축에 저항을 삽입하였고, 각 다이폴 안테나의 포트 임피던스는 발룬을 사용하여 정합하였다. 안테나의 성능 검증을 위하여, 표준전자기장을 만들어주는 GTEM Cell를 사용하여 antenna factor 및 수신감도를 도출하였다. 결과적으로, 제작된 3축 등방성 안테나는 0.03~3 GHz의 넓은 동작주파수 범위 내에서 수신감도 0.12~4.2 mV/m, VSWR(typical)은 3.3:1 이하이다.