401
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Tell RA, Kavet R. ELECTRIC AND MAGNETIC FIELDS <100 KHZ IN ELECTRIC AND GASOLINE-POWERED VEHICLES. RADIATION PROTECTION DOSIMETRY 2016; 172:541-546. [PMID: 26769905 DOI: 10.1093/rpd/ncv533] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 08/12/2015] [Accepted: 11/25/2015] [Indexed: 06/05/2023]
Abstract
Measurements were conducted to investigate electric and magnetic fields (EMFs) from 120 Hz to 10 kHz and 1.2 to 100 kHz in 9 electric or hybrid vehicles and 4 gasoline vehicles, all while being driven. The range of fields in the electric vehicles enclosed the range observed in the gasoline vehicles. Mean magnetic fields ranged from nominally 0.6 to 3.5 µT for electric/hybrids depending on the measurement band compared with nominally 0.4 to 0.6 µT for gasoline vehicles. Mean values of electric fields ranged from nominally 2 to 3 V m-1 for electric/hybrid vehicles depending on the band, compared with 0.9 to 3 V m-1 for gasoline vehicles. In all cases, the fields were well within published exposure limits for the general population. The measurements were performed with Narda model EHP-50C/EHP-50D EMF analysers that revealed the presence of spurious signals in the EHP-50C unit, which were resolved with the EHP-50D model.
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Affiliation(s)
- Richard A Tell
- Richard Tell Associates, Inc., 350 Falcon Ridge Parkway, Suite 103, Mesquite, NV 89027, USA
| | - Robert Kavet
- Electric Power Research Institute, 3420 Hillview Avenue, Palo Alto, CA 94304, USA
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402
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Park S, Kim M. Numerical Exposure Assessment Method for Low Frequency Range and Application to Wireless Power Transfer. PLoS One 2016; 11:e0166720. [PMID: 27898688 PMCID: PMC5127525 DOI: 10.1371/journal.pone.0166720] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/02/2016] [Indexed: 11/19/2022] Open
Abstract
In this paper, a numerical exposure assessment method is presented for a quasi-static analysis by the use of finite-difference time-domain (FDTD) algorithm. The proposed method is composed of scattered field FDTD method and quasi-static approximation for analyzing of the low frequency band electromagnetic problems. The proposed method provides an effective tool to compute induced electric fields in an anatomically realistic human voxel model exposed to an arbitrary non-uniform field source in the low frequency ranges. The method is verified, and excellent agreement with theoretical solutions is found for a dielectric sphere model exposed to a magnetic dipole source. The assessment method serves a practical example of the electric fields, current densities, and specific absorption rates induced in a human head and body in close proximity to a 150-kHz wireless power transfer system for cell phone charging. The results are compared to the limits recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the IEEE standard guidelines.
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Affiliation(s)
- SangWook Park
- EMI/EMC R&D Center, Reliability & Safety R&D Division, Korea Automotive Technology Institute, Cheonan, Korea
- * E-mail:
| | - Minhyuk Kim
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Korea
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403
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Mattei E, Censi F, Calcagnini G, Falsaperla R, Genovese E, Napolitano A, Cannatà V. Pacemaker and ICD oversensing induced by movements near the MRI scanner bore. Med Phys 2016; 43:6621. [DOI: 10.1118/1.4967856] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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404
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Analysis of specific absorption rate and internal electric field in human biological tissues surrounding an air-core coil-type transcutaneous energy transmission transformer. J Artif Organs 2016; 20:103-109. [PMID: 27873104 DOI: 10.1007/s10047-016-0935-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/09/2016] [Indexed: 10/20/2022]
Abstract
In this study, we analyzed the internal electric field E and specific absorption rate (SAR) of human biological tissues surrounding an air-core coil transcutaneous energy transmission transformer. Using an electromagnetic simulator, we created a model of human biological tissues consisting of a dry skin, wet skin, fat, muscle, and cortical bone. A primary coil was placed on the surface of the skin, and a secondary coil was located subcutaneously inside the body. The E and SAR values for the model representing a 34-year-old male subject were analyzed using electrical frequencies of 0.3-1.5 MHz. The transmitting power was 15 W, and the load resistance was 38.4 Ω. The results showed that the E values were below the International Commission on Non-ionizing Radiation Protection (ICNIRP) limit for the general public exposure between the frequencies of 0.9 and 1.5 MHz, and SAR values were well below the limit prescribed by the ICNIRP for the general public exposure between the frequencies of 0.3 and 1.2 MHz.
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405
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Coil Design for High Misalignment Tolerant Inductive Power Transfer System for EV Charging. ENERGIES 2016. [DOI: 10.3390/en9110937] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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406
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Tondato F, Bazzell J, Schwartz L, Mc Donald BW, Fisher R, Anderson SS, Galindo A, Dueck AC, Scott LR. Safety and interaction of patients with implantable cardiac defibrillators driving a hybrid vehicle. Int J Cardiol 2016; 227:318-324. [PMID: 27838127 DOI: 10.1016/j.ijcard.2016.11.090] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 11/06/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Electromagnetic interference (EMI) can affect the function of implantable cardioverter defibrillators (ICD). Hybrid electric vehicles (HEV) have increased popularity and are a potential source of EMI. Little is known about the in vivo effects of EMI generated by HEV on ICD. OBJECTIVE This study evaluated the in vivo interaction between EMI generated by HEV with ICD. METHODS AND RESULTS Thirty patients (73±9 y/o; 80% male) with stable ICD function were exposed to EMI generated by a Toyota Prius Hybrid®. The vehicle was lifted above the ground, allowing safe changes in engine rotation and consequent variations in electromagnetic emission. EMI was measured (NARDA STS® model EHP-50C) and expressed in A/m (magnetic), Volts/m (electrical), and Hertz (frequency). Six positions were evaluated: driver, front passenger, right and left back seats, outside, at the back and front of the car. Each position was evaluated at idle, 30 mph, 60 mph and variable speeds (acceleration-deceleration-brake). All ICD devices were continuously monitored during the study. The levels of EMI generated were low (highest mean levels: 2.09A/m at right back seat at 30 mph; and 3.5V/m at driver seat at variable speeds). No episode of oversensing or inadvertent change in ICD programming was observed. CONCLUSION It is safe for patients with ICD to interact with HEV. This is the first study to address this issue using an in vivo model. Further studies are necessary to evaluate the interaction of different models of HEV or electric engine with ICD or unipolar pacemakers.
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Affiliation(s)
- Fernando Tondato
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Jane Bazzell
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Linda Schwartz
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Bruce W Mc Donald
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Robert Fisher
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - S Shawn Anderson
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Arcenio Galindo
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Amylou C Dueck
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States
| | - Luis R Scott
- Heart Rhythm Section, Department of Cardiology, Mayo Clinic, AZ, United States.
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407
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Zhou L, Wan B, Liu X, Zhang Y, Lai J, Ruan G, He M, Chen C, Wang DW. The effects of a 50-Hz magnetic field on the cardiovascular system in rats. JOURNAL OF RADIATION RESEARCH 2016; 57:627-636. [PMID: 27694282 PMCID: PMC5137297 DOI: 10.1093/jrr/rrw090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/11/2016] [Accepted: 07/28/2016] [Indexed: 06/06/2023]
Abstract
A 50-Hz magnetic field (MF) is a potential health-risk factor. Its effects on the cardiovascular system have not been fully investigated. This study was conducted to explore the effects of long-term exposure to a 50-Hz MF on the cardiovascular system. In the study, an exposure system was constructed, and the distribution of the 50-Hz MF was determined. Sixty-four Sprague-Dawley (SD) rats were exposed to a 50-Hz MF at 100 μT for 24 weeks, 20 h per day, while another 64 rats were sham exposed. During the exposure, blood pressure was measured every 4 weeks. After 24 weeks, echocardiography, cardiac catheterization and electrocardiography were performed. Moreover, heart and body weight were recorded, and haematoxylin-eosin staining and real-time PCR were conducted. The results showed that compared with the sham group, exposure to a 50-Hz MF did not exert any effects on blood pressure, pulse rate, heart rate or cardiac rhythm. Furthermore, echocardiography and cardiac catheterization showed that there were no significant differences in the cardiac morphology or haemodynamics. In addition, histopathological examination showed that exposure to a 50-Hz MF had no effects on the structure of the heart. Finally, expression of the cardiac hypertrophy-related genes did not show any significant differences between the 50-Hz MF exposure group and the sham group. Taken together, in SD rats, exposure to a 50-Hz/100 μT MF for 24 weeks did not show any obvious effects on the cardiovascular system.
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Affiliation(s)
- Ling Zhou
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
| | - Baoquan Wan
- State Key Laboratory of Power Grid Environmental Protection, China Electric Power Research Institute, Wuhan, 430074, China
| | - Xingfa Liu
- State Key Laboratory of Power Grid Environmental Protection, China Electric Power Research Institute, Wuhan, 430074, China
| | - Yemao Zhang
- State Key Laboratory of Power Grid Environmental Protection, China Electric Power Research Institute, Wuhan, 430074, China
| | - Jinsheng Lai
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
| | - Guoran Ruan
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
| | - Mengying He
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
| | - Chen Chen
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
| | - Dao Wen Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, China
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408
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Fiocchi S, Ravazzani P, Priori A, Parazzini M. Cerebellar and Spinal Direct Current Stimulation in Children: Computational Modeling of the Induced Electric Field. Front Hum Neurosci 2016; 10:522. [PMID: 27799905 PMCID: PMC5065976 DOI: 10.3389/fnhum.2016.00522] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 09/30/2016] [Indexed: 01/30/2023] Open
Abstract
Recent studies have shown that the specific application of transcranial direct current stimulation (tDCS) over the cerebellum can modulate cerebellar activity. In parallel, transcutaneous spinal DC stimulation (tsDCS) was found to be able to modulate conduction along the spinal cord and spinal cord functions. Of particular interest is the possible use of these techniques in pediatric age, since many pathologies and injuries, which affect the cerebellar cortex as well as spinal cord circuits, are diffuse in adults as well as in children. Up to now, experimental studies of cerebellar and spinal DC stimulation on children are completely missing and therefore there is a lack of information about the safety of this technique as well as the appropriate dose to be used during the treatment. Therefore, the knowledge of electric quantities induced into the cerebellum and over the spinal cord during cerebellar tDCS and tsDCS, respectively, is required. This work attempts to address this issue by estimating through computational techniques, the electric field distributions induced in the target tissues during the two stimulation techniques applied to different models of children of various ages and gender. In detail, we used four voxel child models, aged between 5- and 8-years. Results revealed that, despite inter-individual differences, the cerebellum is the structure mainly involved by cerebellar tDCS, whereas the electric field generated by tsDCS can reach the spinal cord also in children. Moreover, it was found that there is a considerable spread toward the anterior area of the cerebellum and the brainstem region for cerebellar tDCS and in the spinal nerve for spinal direct current stimulation. Our study therefore predicts that the electric field spreads in complex patterns that strongly depend on individual anatomy, thus giving further insight into safety issues and informing data for pediatric investigations of these stimulation techniques.
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Affiliation(s)
- Serena Fiocchi
- Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni (IEIIT), Consiglio Nazionale delle Ricerche (CNR) Milan, Italy
| | - Paolo Ravazzani
- Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni (IEIIT), Consiglio Nazionale delle Ricerche (CNR) Milan, Italy
| | - Alberto Priori
- Dipartimento di Scienze della Salute, Ospedale San Paolo, Università degli Studi di Milano Milan, Italy
| | - Marta Parazzini
- Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni (IEIIT), Consiglio Nazionale delle Ricerche (CNR) Milan, Italy
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409
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Korpinen L, Pirkkalainen H, Heiskanen T, Pääkkönen R. The Possibility of Decreasing 50-Hz Electric Field Exposure near 400-kV Power Lines with Arc Flash Personal Protective Equipment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13100942. [PMID: 27669278 PMCID: PMC5086681 DOI: 10.3390/ijerph13100942] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 08/27/2016] [Accepted: 09/19/2016] [Indexed: 11/16/2022]
Abstract
Various guidelines for the protection of human beings against possible adverse effects resulting from exposure to electromagnetic fields (EMFs) have been published with a view towards continual improvement; therefore, decreasing exposure is an important research area. The aim of this study was to investigate the possibility of decreasing electric field exposure with arc flash rated personal protective equipment (PPE), which in this case was a set of coveralls, and to compare the measurement results to calculations using the helmet-mask measuring system. We collected the data under a 400-kV power line. The test person stood on isolated aluminum paper, and the current between the ground and the aluminum paper was measured. When the test subject wore the arc flash PPE, the current to the ground was only 9.5% of the current measured when wearing normal clothes, which represents a clear decrease in exposure.
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Affiliation(s)
- Leena Korpinen
- The Clinical Physiology and Neurophysiology Unit, The North Karelia Central Hospital and Honkalampi Centre, Tikkamäentie 16, FIN-80210 Joensuu, Finland.
| | | | | | - Rauno Pääkkönen
- Tampere University of Technology, Korkeakoulunkatu 10, 33720 Tampere, Finland.
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410
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Wood AW, Lajevardipour A, McIntosh RL. Lessons and Perspectives from a 25-Year Bioelectromagnetics Research Program. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13100950. [PMID: 27669282 PMCID: PMC5086689 DOI: 10.3390/ijerph13100950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 11/29/2022]
Abstract
The question of whether electromagnetic fields from electric power or telecommunications systems can be linked unequivocally to health detriments has occupied scientific research endeavors for nearly half a century. For 25 years, the bioelectromagnetic research group at Swinburne University in Melbourne, Australia, has pursued a series of investigations with relevant endpoints, such as neurophysiological and neuropsychological effects, cell calcium level changes, proliferation, and genotoxic effects. Most have shown no significant changes due to fields, however, in some pilot studies significant changes were revealed, but in most cases these were not replicated in follow-up studies. This highlights a feature of this research area, generally; the unambiguous identification of small changes in noisy data where the understanding of possible interaction mechanisms is lacking. On the other hand, mathematical modelling studies, particularly with respect to fields near metallic implants, in workers exposed to fields in harsh environmental conditions and at very high frequencies (THz), continue to add to the expanding knowledge database on the characteristics of the complex electromagnetic environment we live in today.
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Affiliation(s)
- Andrew W Wood
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
| | - Alireza Lajevardipour
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
| | - Robert L McIntosh
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
- Chief Technology Office, Telstra Corporation, Melbourne, VIC 3122, Australia.
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411
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Optimal Magnetic Field Shielding Method by Metallic Sheets in Wireless Power Transfer System. ENERGIES 2016. [DOI: 10.3390/en9090733] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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412
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Fakhri Y, Alinejad A, Keramati H, Bay A, Avazpour M, Zandsalimi Y, Moradi B, Rasouli Amirhajeloo L, Mirzaei M. Survey on Different Samsung with Nokia Smart Mobile Phones in the Specific Absorption Rate Electrical Field of Head. Glob J Health Sci 2016; 8:53967. [PMID: 27157169 PMCID: PMC5064074 DOI: 10.5539/gjhs.v8n9p251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 11/23/2015] [Indexed: 11/21/2022] Open
Abstract
The use of smart phones is increasing in the world. This excessive use, especially in the last two decades, has created too much concern on the effects of emitted electromagnetic fields and specific absorption rate on human health. In this descriptive-analytical study of the electric field resulting from smart phones of Samsung and Nokia by portable measuring device, electromagnetic field, Model HI-3603-VDT/VLF, were measured. Then, head absorption rate was calculated in these two mobiles by ICNIRP equation. Finally, the comparison of specific absorption rate, especially between Samsung and Nokia smart phones, was conducted by T-Test statistics analysis. The mean of electric field for Samsung and Nokia smart mobile phones was obtained 1.8 ±0.19 v/m and 2.23±0.39 v/m , respectively, while the range of the electric field was obtained as 1.56-2.21 v/m and 1.69-2.89 v/m for them, respectively. The mean of specific absorption rate in Samsung and Nokia was obtained 0.002 ± 0.0005 W/Kg and 0.0041±0.0013 W/Kg at the frequency of 900 MHz and 0.004±0.001 W/Kg and 0.0062±0.0002 W/Kg at the frequency of 1800 MHz respectively. The ratio of mean electronic field to guidance in the Samsung mobile phone at the frequency of 900 MHz and 1800 MHz was 4.36% and 3.34%, while was 5.62% and 4.31% in the Nokia mobile phone, respectively. The ratio of mean head specific absorption rate in smart mobile phones of Samsung and Nokia in the guidance level at the frequency of 900 was 0.15% and 0.25%, respectively, while was 0.23 %and 0.38% at the frequency of 1800 MHz, respectively. The rate of specific absorption of Nokia smart mobile phones at the frequencies of 900 and 1800 MHz was significantly higher than Samsung (p value <0.05). Hence, we can say that in a fixed period, health risks of Nokia smart phones is higher than Samsung smart mobile phone.
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413
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Gajšek P, Ravazzani P, Grellier J, Samaras T, Bakos J, Thuróczy G. Review of Studies Concerning Electromagnetic Field (EMF) Exposure Assessment in Europe: Low Frequency Fields (50 Hz-100 kHz). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:E875. [PMID: 27598182 PMCID: PMC5036708 DOI: 10.3390/ijerph13090875] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 08/01/2016] [Accepted: 08/23/2016] [Indexed: 11/17/2022]
Abstract
We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.
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Affiliation(s)
- Peter Gajšek
- Institute of Non-Ionizing Radiation (INIS), Pohorskega Bataljona 215, Ljubljana 1000, Slovenia
| | - Paolo Ravazzani
- Istituto di Elettronica e di Ingegneria dell’Informazione e delle Telecomunicazioni IEIIT, CNR Consiglio Nazionale delle Ricerche, Piazza Leonardo da Vinci 32, Milan 20133, Italy;
| | - James Grellier
- European Centre for Environment and Human Health (ECEHH), University of Exeter Medical School, Knowledge Spa, Royal Cornwall Hospital, Truro, Cornwall TR1 3HD, UK;
- Formerly Centre for Research in Environmental Epidemiology (CREAL), Parc de Recerca Biomèdica de Barcelona, Doctor Aiguader, 88, Barcelona 08003, Spain
| | - Theodoros Samaras
- Formerly Centre for Research in Environmental Epidemiology (CREAL), Parc de Recerca Biomèdica de Barcelona, Doctor Aiguader, 88, Barcelona 08003, Spain
| | - József Bakos
- Department of Physics, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece;
| | - György Thuróczy
- Department of Physics, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece;
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414
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Magne I, Deschamps F. Electric field induced in the human body by uniform 50 Hz electric or magnetic fields: bibliography analysis and method for conservatively deriving measurable limits. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2016; 36:419-436. [PMID: 27340133 DOI: 10.1088/0952-4746/36/3/419] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Health guidelines for electric and magnetic fields in the low frequency range define exposure limits for electric and magnetic fields in terms of induced electric field in the human body, which is not directly measurable, requiring use of dosimetry. However many parameters, such as human models, calculation codes and post-processing methods influence the calculation results. Based upon many published papers and therefore covering a wide range of these influence parameters, this paper proposes a method for conservatively deriving measurable levels of electric and magnetic fields equivalent to the basic restrictions. Following this method, we found that, regarding exposure to uniform fields, the ICNIRP 2010 occupational basic restrictions are equivalent to a 2 mT and 7 mT magnetic field and to a 35 kV m-1 and 35 kV m-1 electric field at 50 Hz when applied respectively to the central and peripheral nervous system.
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Affiliation(s)
- Isabelle Magne
- Electrical Equipement Laboratory, EDF R&D, Moret sur Loing, France
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415
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Makarov SN, Yanamadala J, Piazza MW, Helderman AM, Thang NS, Burnham EH, Pascual-Leone A. Preliminary Upper Estimate of Peak Currents in Transcranial Magnetic Stimulation at Distant Locations From a TMS Coil. IEEE Trans Biomed Eng 2016; 63:1944-1955. [PMID: 26685221 PMCID: PMC5845790 DOI: 10.1109/tbme.2015.2507572] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
GOALS Transcranial magnetic stimulation (TMS) is increasingly used as a diagnostic and therapeutic tool for numerous neuropsychiatric disorders. The use of TMS might cause whole-body exposure to undesired induced currents in patients and TMS operators. The aim of this study is to test and justify a simple analytical model known previously, which may be helpful as an upper estimate of eddy current density at a particular distant observation point for any body composition and any coil setup. METHODS We compare the analytical solution with comprehensive adaptive mesh refinement-based FEM simulations of a detailed full-body human model, two coil types, five coil positions, about 100 000 observation points, and two distinct pulse rise times; thus, providing a representative number of different datasets for comparison, while also using other numerical data. RESULTS Our simulations reveal that, after a certain modification, the analytical model provides an upper estimate for the eddy current density at any location within the body. In particular, it overestimates the peak eddy currents at distant locations from a TMS coil by a factor of 10 on average. CONCLUSION The simple analytical model tested in this study may be valuable as a rapid method to safely estimate levels of TMS currents at different locations within a human body. SIGNIFICANCE At present, safe limits of general exposure to TMS electric and magnetic fields are an open subject, including fetal exposure for pregnant women.
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416
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Hansson Mild K, Friberg S, Frankel J, Wilén J. Exposure to the magnetic field from an induction loop pad for a hearing aid system. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2016; 23:143-145. [PMID: 27541365 DOI: 10.1080/10803548.2016.1226597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
As a case study we have measured the magnetic field from an induction loop pad designed for hearing aid assistance. The magnitude of the field was high, although well below international guidelines. We recorded values up to 70% of the recommended standard in some instances. However, in view of the many reports indicating health effects of low-level exposure, we recommend that the precautionary principle is applied when such pads are given to people who might be especially vulnerable, such as children, pregnant women and women on breast cancer medication.
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Affiliation(s)
| | - Stefan Friberg
- b Department of Audiology , University Hospital of Umeå , Sweden
| | | | - Jonna Wilén
- a Department of Radiation Sciences , Umeå University , Sweden
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417
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Nakayama M, Nakamura A, Hondou T, Miyata H. Evaluation of cell viability, DNA single-strand breaks, and nitric oxide production in LPS-stimulated macrophage RAW264 exposed to a 50-Hz magnetic field. Int J Radiat Biol 2016; 92:583-9. [DOI: 10.1080/09553002.2016.1206224] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Maresuke Nakayama
- Department of Physics, Tohoku University, Aoba-ku Aramaki, Sendai, Miyagi, Japan
| | - Aya Nakamura
- Department of Physics, Tohoku University, Aoba-ku Aramaki, Sendai, Miyagi, Japan
| | - Tsuyoshi Hondou
- Department of Physics, Tohoku University, Aoba-ku Aramaki, Sendai, Miyagi, Japan
| | - Hidetake Miyata
- Department of Physics, Tohoku University, Aoba-ku Aramaki, Sendai, Miyagi, Japan
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418
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Quality Matters: Systematic Analysis of Endpoints Related to "Cellular Life" in Vitro Data of Radiofrequency Electromagnetic Field Exposure. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13070701. [PMID: 27420084 PMCID: PMC4962242 DOI: 10.3390/ijerph13070701] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 07/04/2016] [Accepted: 07/05/2016] [Indexed: 01/09/2023]
Abstract
Possible hazardous effects of radiofrequency electromagnetic fields (RF-EMF) at low exposure levels are controversially discussed due to inconsistent study findings. Therefore, the main focus of the present study is to detect if any statistical association exists between RF-EMF and cellular responses, considering cell proliferation and apoptosis endpoints separately and with both combined as a group of “cellular life” to increase the statistical power of the analysis. We searched for publications regarding RF-EMF in vitro studies in the PubMed database for the period 1995–2014 and extracted the data to the relevant parameters, such as cell culture type, frequency, exposure duration, SAR, and five exposure-related quality criteria. These parameters were used for an association study with the experimental outcome in terms of the defined endpoints. We identified 104 published articles, from which 483 different experiments were extracted and analyzed. Cellular responses after exposure to RF-EMF were significantly associated to cell lines rather than to primary cells. No other experimental parameter was significantly associated with cellular responses. A highly significant negative association with exposure condition-quality and cellular responses was detected, showing that the more the quality criteria requirements were satisfied, the smaller the number of detected cellular responses. According to our knowledge, this is the first systematic analysis of specific RF-EMF bio-effects in association to exposure quality, highlighting the need for more stringent quality procedures for the exposure conditions.
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419
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Golbach LA, Portelli LA, Savelkoul HFJ, Terwel SR, Kuster N, de Vries RBM, Verburg-van Kemenade BML. Calcium homeostasis and low-frequency magnetic and electric field exposure: A systematic review and meta-analysis of in vitro studies. ENVIRONMENT INTERNATIONAL 2016; 92-93:695-706. [PMID: 26872872 DOI: 10.1016/j.envint.2016.01.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 12/10/2015] [Accepted: 01/18/2016] [Indexed: 05/24/2023]
Abstract
Low frequency magnetic field (LF MF) exposure is recurrently suggested to have the ability to induce health effects in society. Therefore, in vitro model systems are used to investigate biological effects of exposure. LF MF induced changes of the cellular calcium homeostasis are frequently hypothesised to be the possible target, but this hypothesis is both substantiated and rejected by numerous studies in literature. Despite the large amount of data, no systematic analysis of in vitro studies has been conducted to address the strength of evidence for an association between LF MF exposure and calcium homeostasis. Our systematic review, with inclusion of 42 studies, showed evidence for an association of LF MF with internal calcium concentrations and calcium oscillation patterns. The oscillation frequency increased, while the amplitude and the percentage of oscillating cells remained constant. The intracellular calcium concentration increased (SMD 0.351, 95% CI 0.126, 0.576). Subgroup analysis revealed heterogeneous effects associated with the exposure frequency, magnetic flux density and duration. Moreover, we found support for the presence of MF-sensitive cell types. Nevertheless, some of the included studies may introduce a great risk of bias as a result of uncontrolled or not reported exposure conditions, temperature ranges and ambient fields. In addition, mathematical calculations of the parasitic induced electric fields (IEFs) disclosed their association with increased intracellular calcium. Our results demonstrate that LF MF might influence the calcium homeostasis in cells in vitro, but the risk of bias and high heterogeneity (I(2)>75%) weakens the analyses. Therefore any potential clinical implications await further investigation.
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Affiliation(s)
- Lieke A Golbach
- Cell Biology and Immunology Group, Wageningen University, P.O.Box 338, 6700AH Wageningen, The Netherlands
| | - Lucas A Portelli
- The Foundation for Research on Information Technologies in Society (IT'IS), Zeughausstrasse 43, CH-8004 Zurich, Switzerland
| | - Huub F J Savelkoul
- Cell Biology and Immunology Group, Wageningen University, P.O.Box 338, 6700AH Wageningen, The Netherlands
| | - Sofie R Terwel
- Cell Biology and Immunology Group, Wageningen University, P.O.Box 338, 6700AH Wageningen, The Netherlands
| | - Niels Kuster
- The Foundation for Research on Information Technologies in Society (IT'IS), Zeughausstrasse 43, CH-8004 Zurich, Switzerland; Department of Information Technology and Electrical Engineering, Swiss Federal Technical Institute (ETHZ), Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Rob B M de Vries
- SYRCLE, Central Animal Laboratory, Radboud University Medical Center, The Netherlands
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420
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Tarao H, Miyamoto H, Korpinen L, Hayashi N, Isaka K. Simple estimation of induced electric fields in nervous system tissues for human exposure to non-uniform electric fields at power frequency. Phys Med Biol 2016; 61:4438-51. [PMID: 27222929 DOI: 10.1088/0031-9155/61/12/4438] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Most results regarding induced current in the human body related to electric field dosimetry have been calculated under uniform field conditions. We have found in previous work that a contact current is a more suitable way to evaluate induced electric fields, even in the case of exposure to non-uniform fields. If the relationship between induced currents and external non-uniform fields can be understood, induced electric fields in nervous system tissues may be able to be estimated from measurements of ambient non-uniform fields. In the present paper, we numerically calculated the induced electric fields and currents in a human model by considering non-uniform fields based on distortion by a cubic conductor under an unperturbed electric field of 1 kV m(-1) at 60 Hz. We investigated the relationship between a non-uniform external electric field with no human present and the induced current through the neck, and the relationship between the current through the neck and the induced electric fields in nervous system tissues such as the brain, heart, and spinal cord. The results showed that the current through the neck can be formulated by means of an external electric field at the central position of the human head, and the distance between the conductor and the human model. As expected, there is a strong correlation between the current through the neck and the induced electric fields in the nervous system tissues. The combination of these relationships indicates that induced electric fields in these tissues can be estimated solely by measurements of the external field at a point and the distance from the conductor.
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Affiliation(s)
- Hiroo Tarao
- National Institute of Technology, Kagawa College, 355 Chokushi-cho, Takamatsu, Kagawa 761-8058, Japan
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421
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Hikage T, Nojima T, Fujimoto H. Active implantable medical device EMI assessment for wireless power transfer operating in LF and HF bands. Phys Med Biol 2016; 61:4522-36. [PMID: 27224201 DOI: 10.1088/0031-9155/61/12/4522] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The electromagnetic interference (EMI) imposed on active implantable medical devices by wireless power transfer systems (WPTSs) is discussed based upon results of in vitro experiments. The purpose of this study is to present comprehensive EMI test results gathered from implantable-cardiac pacemakers and implantable cardioverter defibrillators exposed to the electromagnetic field generated by several WPTSs operating in low-frequency (70 kHz-460 kHz) and high-frequency (6.78 MHz) bands. The constructed in vitro experimental test system based upon an Irnich's flat torso phantom was applied. EMI test experiments are conducted on 14 types of WPTSs including Qi-compliant system and EV-charging WPT system mounted on current production EVs. In addition, a numerical simulation model for active implantable medical device (AIMD) EMI estimation based on the experimental test system is newly proposed. The experimental results demonstrate the risk of WPTSs emitting intermittent signal to affect the correct behavior of AIMDs when operating at very short distances. The proposed numerical simulation model is applicable to obtain basically the EMI characteristics of various types of WPTSs.
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Affiliation(s)
- Takashi Hikage
- Graduate School of Information Science and Technology, Hokkaido University, Kita14, Nishi9, Kita-ku, Sapporo, Hokkaido, Japan
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422
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Ghadamgahi M, Monazzam MR, Hosseini M. Memory loss risk assessment for the students nearby high-voltage power lines-a case study. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:355. [PMID: 27194231 DOI: 10.1007/s10661-016-5358-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 05/09/2016] [Indexed: 06/05/2023]
Abstract
With increasing sources of alternating current electromagnetic fields (EMFs) in everyday life, their possible harmful effects on human health are a main area of concern in many countries. Given that children are the most valuable assets of each country, it is of utmost importance to study the effect(s) of EMF exposure on various health aspects of members within this age group. The present research is the first systematic study of the effects of exposure to electric substations on the memory status of male students in the age group of 10 to 12 years. The flux density values of extremely low frequency magnetic field were measured at four elementary schools in Tehran in accordance with IEEE std 644-1994. The device was 3-axis (X, Y, and Z) Gauss Meter, model: TES-1394. The students from two schools nearby a high voltage electricity substation (at distances of 30 and 50 m) were selected as the exposed group, and the students of two other schools at further distances of 1390 and 610 m were considered as the control group. To determine the status of working memory in the students, the questionnaire was adapted from Wechsler Intelligence Scale for Children (WISC-IV). The completed questionnaires were analyzed by t test and chi-square using SPSS 20. The average magnetic flux density was 0.245 μT at case schools and 0.164 μT at control schools, P < 0.01. The demographic characteristics of the students in the two groups were not statistically different. However, the difference in working memory was significant at the level of 5 %. The results of the questionnaire data showed that students in the control group had better working memory compared to students in case group. The findings revealed a reverse correlation between magnetic flux density and working memory of students (R = -0.255). It is concluded that extremely low frequency magnetic field exposure may have a negative impact on the working memory of children, but further studies are necessary to reach a definitive conclusion.
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Affiliation(s)
- Mojgan Ghadamgahi
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Pharmaceutical Sciences Branch, Islamic Azad University, (IAUPS), Tehran, Iran
| | - Mohammad Reza Monazzam
- Department of Occupational Hygiene, School of Public Health and Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran
| | - Monireh Hosseini
- Department of Physics, Faculty of Basic Sciences, Islamic Azad University- North Tehran Branch and Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran.
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423
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Reilly JP, Hirata A. Low-frequency electrical dosimetry: research agenda of the IEEE International Committee on Electromagnetic Safety. Phys Med Biol 2016; 61:R138-49. [PMID: 27223463 DOI: 10.1088/0031-9155/61/12/r138] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This article treats unsettled issues in the use of numerical models of electrical dosimetry as applied to international limits on human exposure to low-frequency (typically < 100 kHz) electromagnetic fields and contact current. The perspective in this publication is that of Subcommittee 6 of IEEE-ICES (International Committee on Electromagnetic Safety) Technical Committee 95. The paper discusses 25 issues needing attention, fitting into three general categories: induction models; electrostimulation models; and human exposure limits. Of these, 9 were voted as 'high priority' by members of Subcommittee 6. The list is presented as a research agenda for refinements in numerical modeling with applications to human exposure limits. It is likely that such issues are also important in medical and electrical product safety design applications.
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424
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De Santis V, Chen XL, Cruciani S, Campi T, Feliziani M. A novel homogenization procedure to model the skin layers in LF numerical dosimetry. Phys Med Biol 2016; 61:4402-11. [DOI: 10.1088/0031-9155/61/12/4402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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425
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Schmid G, Hirtl R. On the importance of body posture and skin modelling with respect toin situelectric field strengths in magnetic field exposure scenarios. Phys Med Biol 2016; 61:4412-37. [DOI: 10.1088/0031-9155/61/12/4412] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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426
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Motogi J, Sugiyama Y, Laakso I, Hirata A, Inui K, Tamura M, Muragaki Y. Why intra-epidermal electrical stimulation achieves stimulation of small fibres selectively: a simulation study. Phys Med Biol 2016; 61:4479-90. [DOI: 10.1088/0031-9155/61/12/4479] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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427
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Wake K, Sasaki K, Watanabe S. Conductivities of epidermis, dermis, and subcutaneous tissue at intermediate frequencies. Phys Med Biol 2016; 61:4376-89. [DOI: 10.1088/0031-9155/61/12/4376] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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428
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Korpinen L, Kuisti H, Elovaara J. Current densities and total contact currents during forest clearing tasks under 400 kV power lines. Bioelectromagnetics 2016; 37:423-8. [PMID: 27192179 PMCID: PMC5084735 DOI: 10.1002/bem.21980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 04/25/2016] [Indexed: 11/11/2022]
Abstract
The aim of the study was to analyze all values of electric currents from measured periods while performing tasks in forest clearing. The objective was also to choose and analyze measurement cases, where current measurements successfully lasted the entire work period (about 30 min). Two forestry workers volunteered to perform four forest clearing tasks under 400 kV power lines. The sampling frequency of the current measurements was 1 sample/s. The maximum values of the current densities were 1.0–1.2 mA/m2 (calculated internal EFs 5.0–12.0 mV/m), and the average values were 0.2–0.4 mA/m2. The highest contact current was 167.4 μA. All measured values during forest clearing tasks were lower than basic restrictions (0.1 V/m and 0.8 V/m) of the International Commission on Non‐Ionizing Radiation Protection. Bioelectromagnetics. 37:423–428, 2016. © 2016 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.
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Affiliation(s)
- Leena Korpinen
- Environmental HealthTampere University of TechnologyTampereFinland
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429
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Calabrò E. Competition between hydrogen bonding and protein aggregation in neuronal-like cells under exposure to 50 Hz magnetic field. Int J Radiat Biol 2016; 92:395-403. [DOI: 10.1080/09553002.2016.1175679] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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430
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Gong Y, Capstick M, Dasenbrock C, Fedrowitz M, Cobaleda C, Sánchez-García I, Kuster N. Comparative dosimetry for children and rodents exposed to extremely low-frequency magnetic fields. Bioelectromagnetics 2016; 37:310-22. [DOI: 10.1002/bem.21976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 03/23/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Yijian Gong
- IT'IS Foundation; Zurich Switzerland
- Information Technology and Electrical Engineering; ETHZ; Zurich Switzerland
| | | | | | - Maren Fedrowitz
- Department of Pharmacology, Toxicology, and Pharmacy; University of Veterinary Medicine; Hannover Germany
| | - Cesar Cobaleda
- Centro de Biologia Molecular Severo Ochoa; CSIC/UAM; Madrid Spain
| | - Isidro Sánchez-García
- Experimental Therapeutics and Translational Oncology Program; Instituto de Biología Molecular y Celular del Cáncer; CSIC/Universidad de Salamanca; Salamanca Spain
| | - Niels Kuster
- IT'IS Foundation; Zurich Switzerland
- Information Technology and Electrical Engineering; ETHZ; Zurich Switzerland
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431
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Shen Y, Xia R, Jiang H, Chen Y, Hong L, Yu Y, Xu Z, Zeng Q. Exposure to 50Hz-sinusoidal electromagnetic field induces DNA damage-independent autophagy. Int J Biochem Cell Biol 2016; 77:72-79. [PMID: 27177844 DOI: 10.1016/j.biocel.2016.05.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 04/21/2016] [Accepted: 05/08/2016] [Indexed: 01/22/2023]
Abstract
As electromagnetic field (EMF) is commonly encountered within our daily lives, the biological effects of EMF are of great concern. Autophagy is a key process for maintaining cellular homeostasis, and it can also reveal cellular responses to environmental stimuli. In this study, we aim to investigate the biological effects of a 50Hz-sinusoidal electromagnetic field on autophagy and we identified its mechanism of action in Chinese Hamster Lung (CHL) cells. CHL cells were exposed to a 50Hz sinusoidal EMF at 0.4mT for 30min or 24h. In this study, we found that a 0.4mT EMF resulted in: (i) an increase in LC3-II expression and increased autophagosome formation; (ii) no significant difference in the incidence of γH2AX foci between the sham and exposure groups; (iii) reorganized actin filaments and increased pseudopodial extensions without promoting cell migration; and (iv) enhanced cell apoptosis when autophagy was blocked by Bafilomycin A1. These results implied that DNA damage was not directly involved in the autophagy induced by a 0.4mT 50Hz EMF. In addition, an EMF induced autophagy balanced the cellular homeostasis to protect the cells from severe adverse biological consequences.
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Affiliation(s)
- Yunyun Shen
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Ruohong Xia
- Physics Department, East China Normal University, Shanghai 200241, PR China
| | - Hengjun Jiang
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Yanfeng Chen
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Ling Hong
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Yunxian Yu
- Department of Epidemiology and Health Statistics, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Zhengping Xu
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China.
| | - Qunli Zeng
- Bioelectromagnetics Laboratory, Department of Occupational and Environmental Health, School of Public Health, School of Medicine, Zhejiang University, Hangzhou 310058, PR China.
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432
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Feychting M. Deep brain stimulation and glioma. Acta Neurochir (Wien) 2016; 158:919-20. [PMID: 27005672 DOI: 10.1007/s00701-016-2776-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 03/09/2016] [Indexed: 10/22/2022]
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433
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Exposure to an Extremely-Low-Frequency Magnetic Field Stimulates Adrenal Steroidogenesis via Inhibition of Phosphodiesterase Activity in a Mouse Adrenal Cell Line. PLoS One 2016; 11:e0154167. [PMID: 27100201 PMCID: PMC4839720 DOI: 10.1371/journal.pone.0154167] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 04/08/2016] [Indexed: 11/23/2022] Open
Abstract
Extremely low-frequency magnetic fields (ELF-MFs) are generated by power lines and household electrical devices. In the last several decades, some evidence has shown an association between ELF-MF exposure and depression and/or anxiety in epidemiological and animal studies. The mechanism underlying ELF-MF-induced depression is considered to involve adrenal steroidogenesis, which is triggered by ELF-MF exposure. However, how ELF-MFs stimulate adrenal steroidogenesis is controversial. In the current study, we investigated the effect of ELF-MF exposure on the mouse adrenal cortex-derived Y-1 cell line and the human adrenal cortex-derived H295R cell line to clarify whether the ELF-MF stimulates adrenal steroidogenesis directly. ELF-MF exposure was found to significantly stimulate adrenal steroidogenesis (p < 0.01–0.05) and the expression of adrenal steroid synthetic enzymes (p < 0.05) in Y-1 cells, but the effect was weak in H295R cells. Y-1 cells exposed to an ELF-MF showed significant decreases in phosphodiesterase activity (p < 0.05) and intracellular Ca2+ concentration (p < 0.01) and significant increases in intracellular cyclic adenosine monophosphate (cAMP) concentration (p < 0.001–0.05) and cAMP response element-binding protein phosphorylation (p < 0.05). The increase in cAMP was not inhibited by treatment with NF449, an inhibitor of the Gs alpha subunit of G protein. Our results suggest that ELF-MF exposure stimulates adrenal steroidogenesis via an increase in intracellular cAMP caused by the inhibition of phosphodiesterase activity in Y-1 cells. The same mechanism may trigger the increase in adrenal steroid secretion in mice observed in our previous study.
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434
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Korpinen L, Pääkkönen R. Occupational exposure to electric and magnetic fields during tasks at ground or floor level at 110 kV substations in Finland. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2016; 22:384-8. [PMID: 27075421 PMCID: PMC4960502 DOI: 10.1080/10803548.2016.1153858] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim was to investigate occupational exposure to electric and magnetic fields during tasks at ground or floor level at 110 kV substations in Finland and to compare the measured values to Directive 2013/35/EU. Altogether, 347 electric field measurements and 100 magnetic field measurements were performed. The average value of all electric fields was 2.3 kV/m (maximum 6.4 kV/m) and that of magnetic fields was 5.8 µT (maximum 51.0 µT). It can be concluded that the electric and magnetic field exposure at ground or floor level is typically below the low action levels of Directive 2013/35/EU. The transposition of the directive will not create new needs to modify the work practice of the evaluated tasks, which can continue to be performed as before. However, for workers with medical implants, the exposure may be high enough to cause interference.
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435
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Samoudi AM, Vermeeren G, Tanghe E, Van Holen R, Martens L, Josephs W. Numerically simulated exposure of children and adults to pulsed gradient fields in MRI. J Magn Reson Imaging 2016; 44:1360-1367. [PMID: 27043243 DOI: 10.1002/jmri.25257] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 03/13/2016] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To determine exposure to gradient switching fields of adults and children in a magnetic resonance imaging (MRI) scanner by evaluating internal electric fields within realistic models of adult male, adult female, and child inside transverse and longitudinal gradient coils, and to compare these results with compliance guidelines. MATERIALS AND METHODS Patients inside x-, y-, and z-gradient coils were simulated using anatomically realistic models of adult male, adult female, and child. The induced electric fields were computed for 1 kHz sinusoidal current with a magnitude of 1 A in the gradient coils. Rheobase electric fields were then calculated and compared to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2004 and International Electrotechnical Commission (IEC) 2010 guidelines. The effect of the human body, coil type, and skin conductivity on the induced electric field was also investigated. RESULTS The internal electric fields are within the first level controlled operating mode of the guidelines and range from 2.7V m-1 to 4.5V m-1 , except for the adult male inside the y-gradient coil (induced field reaches 5.4V m-1 ).The induced electric field is sensitive to the coil type (electric field in the skin of adult male: 4V m-1 , 4.6V m-1 , and 3.8V m-1 for x-, y-, and z-gradient coils, respectively), the human body model (electric field in the skin inside y-gradient coil: 4.6V m-1 , 4.2V m-1 , and 3V m-1 for adult male, adult female, and child, respectively), and the skin conductivity (electric field 2.35-4.29% higher for 0.1S m-1 skin conductivity compared to 0.2S m-1 ). CONCLUSION The y-gradient coil induced the largest fields in the patients. The highest levels of internal electric fields occurred for the adult male model. J. Magn. Reson. Imaging 2016;44:1360-1367.
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Affiliation(s)
- Amine M Samoudi
- Department of Information Technology (INTEC), Ghent University/iMinds, iGent, Ghent, Belgium.
| | - Gunter Vermeeren
- Department of Information Technology (INTEC), Ghent University/iMinds, iGent, Ghent, Belgium
| | - Emmeric Tanghe
- Department of Information Technology (INTEC), Ghent University/iMinds, iGent, Ghent, Belgium
| | - Roel Van Holen
- Electronics and Information Systems (ELIS), Ghent University/iMinds, Ghent, Belgium
| | - Luc Martens
- Department of Information Technology (INTEC), Ghent University/iMinds, iGent, Ghent, Belgium
| | - Wout Josephs
- Department of Information Technology (INTEC), Ghent University/iMinds, iGent, Ghent, Belgium
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436
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de Vocht F, Olsen RG. Systematic Review of the Exposure Assessment and Epidemiology of High-Frequency Voltage Transients. Front Public Health 2016; 4:52. [PMID: 27066469 PMCID: PMC4810027 DOI: 10.3389/fpubh.2016.00052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/14/2016] [Indexed: 11/21/2022] Open
Abstract
Conclusions of epidemiological studies describing adverse health effects as a result of exposure to electromagnetic fields are not unanimous and often contradictory. It has been proposed that an explanation could be that high-frequency voltage transients [dirty electricity (DE)] which are superimposed on 50/60-Hz fields, but are generally not measured, are the real causal agent. DE has been linked to many different health and wellbeing effects, and on the basis of this, an industry selling measurement and filtering equipment is growing. We reviewed the available peer-reviewed evidence for DE as a causal agent for adverse human health effects. A literature search was performed in the Cochrane Library, PubMed, Web of Science, Google Scholar, and additional publications were obtained from reference lists and from the gray literature. This search resulted in 25 publications; 16 included primary epidemiological and/or exposure data. All studies were reviewed by both authors independently, and including a re-review of studies included in a review of data available up to July 31, 2009 by one of the authors. DE has been measured differently in different studies and comparison data are not available. There is no evidence for 50 Graham/Stetzer (GS) units as a safety threshold being anything more than arbitrary. The epidemiological evidence on human health effects of DE is primarily based on, often re-used, case descriptions. Quantitative evidence relies on self-reporting in non-blinded interventions, ecological associations, and one cross-sectional cohort study of cancer risk, which does not point to DE as the causal agent. The available evidence for DE as an exposure affecting human health at present does not stand up to scientific scrutiny.
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Affiliation(s)
- Frank de Vocht
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Robert G. Olsen
- School of Electrical Engineering and Computer Science, Washington State University, Pullman, WA, USA
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437
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Shimamoto T, Iwahashi M, Sugiyama Y, Laakso I, Hirata A, Onishi T. SAR evaluation in models of an adult and a child for magnetic field from wireless power transfer systems at 6.78 MHz. Biomed Phys Eng Express 2016. [DOI: 10.1088/2057-1976/2/2/027001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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438
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Iachininoto MG, Camisa V, Leone L, Pinto R, Lopresto V, Merla C, Giorda E, Carsetti R, Zaffina S, Podda MV, Teofili L, Grassi C. Effects of exposure to gradient magnetic fields emitted by nuclear magnetic resonance devices on clonogenic potential and proliferation of human hematopoietic stem cells. Bioelectromagnetics 2016; 37:201-11. [PMID: 26992028 DOI: 10.1002/bem.21967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 02/26/2016] [Indexed: 01/29/2023]
Abstract
This study investigates effects of gradient magnetic fields (GMFs) emitted by magnetic resonance imaging (MRI) devices on hematopoietic stem cells. Field measurements were performed to assess exposure to GMFs of staff working at 1.5 T and 3 T MRI units. Then an exposure system reproducing measured signals was realized to expose in vitro CD34+ cells to GMFs (1.5 T-protocol and 3 T-protocol). CD34+ cells were obtained by Fluorescence Activated Cell Sorting from six blood donors and three MRI-exposed workers. Blood donor CD34+ cells were exposed in vitro for 72 h to 1.5 T or 3 T-protocol and to sham procedure. Cells were then cultured and evaluated in colony forming unit (CFU)-assay up to 4 weeks after exposure. Results showed that in vitro GMF exposure did not affect cell proliferation but instead induced expansion of erythroid and monocytes progenitors soon after exposure and for the subsequent 3 weeks. No decrease of other clonogenic cell output (i.e., CFU-granulocyte/erythroid/macrophage/megakaryocyte and CFU-granulocyte/macrophage) was noticed, nor exposed CD34+ cells underwent the premature exhaustion of their clonogenic potential compared to sham-exposed controls. On the other hand, pilot experiments showed that CD34+ cells exposed in vivo to GMFs (i.e., samples from MRI workers) behaved in culture similarly to sham-exposed CD34+ cells, suggesting that other cells and/or microenvironment factors might prevent GMF effects on hematopoietic stem cells in vivo. Accordingly, GMFs did not affect the clonogenic potential of umbilical cord blood CD34+ cells exposed in vitro together with the whole mononuclear cell fraction.
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Affiliation(s)
| | - Vincenzo Camisa
- Occupational Medicine/Health Technology Assessment and Safety Research Unit, Clinical-Technological Innovations Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Lucia Leone
- Institute of Human Physiology, Università Cattolica, Rome, Italy
| | - Rosanna Pinto
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Vanni Lopresto
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Caterina Merla
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Ezio Giorda
- Immunology Unit, Immunology and Pharmacotherapy Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Rita Carsetti
- Immunology Unit, Immunology and Pharmacotherapy Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Salvatore Zaffina
- Occupational Medicine/Health Technology Assessment and Safety Research Unit, Clinical-Technological Innovations Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | | | - Luciana Teofili
- Department of Transfusion Medicine, Institute of Hematology, Università Cattolica, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica, Rome, Italy.,San Raffaele Pisana Scientific Institute for Research, Hospitalization and Health Care, Rome, Italy
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439
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Zhu K, Lv Y, Cheng Q, Hua J, Zeng Q. Extremely Low Frequency Magnetic Fields Do Not Induce DNA Damage in Human Lens Epithelial Cells In Vitro. Anat Rec (Hoboken) 2016; 299:688-97. [PMID: 27079842 DOI: 10.1002/ar.23312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Revised: 10/30/2015] [Accepted: 11/26/2015] [Indexed: 11/10/2022]
Abstract
Non-ionizing radiations, e.g., radiofrequency electromagnetic fields, could induce DNA damage and oxidative stress in human lens epithelial cells (LECs) which can be early events in cataractogenesis. Extremely low frequency magnetic fields (ELF MF) as another common form of man-made electromagnetic fields has been considered as suspected human carcinogen by International Agency for Research on Cancer (IARC) and become a focus that people play more and more attentions to. This study aimed to determine whether ELF MF can induce DNA damage in cultured human LECs at a relatively low intensity. Human LECs were exposed or sham-exposed to a 50 Hz ELF MF which produced by a well-designed exposure system at the intensity of 0.4 mT. DNA damage in human LECs was examined by the phosphorylated form of histone variant H2AX (γH2AX) foci formation assay and further explored with western blot, flow cytometry, and alkaline comet assay. Immunofluorescence analysis showed that 0.4 mT ELF MF did not significantly increase γH2AX foci formation in human LECs after 2, 6, 12, 24, or 48 hr exposure. No significant differences had been detected in γH2AX expression level between the ELF MF- and sham-exposure groups, while no obvious chromosomal DNA fragmentation was detected by alkaline comet assay after ELF MF exposure. The results indicate an absence of genotoxicity in ELF MF-exposed human epithelial cells and do not support the hypothesis that environmental ELF MF might be causally led to genomic instability via chromosomal damage response processes. Neither short nor long term continuous exposure to 50 Hz ELF MF at 0.4 mT could induce DNA damage in human lens epithelial cells in vitro.
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Affiliation(s)
- Kan Zhu
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Ye Lv
- Department of environmental and occupational health, Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Qian Cheng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.,Department of health monitoring, Haining Center for Disease Control and Prevention, Haining, China
| | - Jianing Hua
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Qunli Zeng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
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440
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Long-term exposure to ELF-MF ameliorates cognitive deficits and attenuates tau hyperphosphorylation in 3xTg AD mice. Neurotoxicology 2016; 53:290-300. [PMID: 26945731 DOI: 10.1016/j.neuro.2016.02.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 02/24/2016] [Accepted: 02/29/2016] [Indexed: 12/30/2022]
Abstract
Although numerous studies have reported the influence of extremely low frequency magnetic field (ELF-MF) exposure on human health, its effects on cognitive deficits in Alzheimer's disease (AD) have remained under debate. Moreover, the influence of ELF-MF on hyperphosphorylated tau, which is one of the most common pathological hallmarks of AD, has not been reported to date. Therefore, transgenic mice (3xTg) were used in the present study. 3xTg mice, which express an APP/PS1 mutation combined with a tau (P301L) mutation and that develop cognitive deficits at 6 months of age, were subjected to ELF-MF (50Hz, 500μT) exposure or sham exposure daily for 3 months. We discovered that ELF-MF exposure ameliorated cognitive deficits and increased synaptic proteins in 3xTg mice. The protective effects of ELF-MF exposure may have also been caused by the inhibition of apoptosis and/or decreased oxidative stress levels that were observed in the hippocampus tissues of treated mice. Furthermore, tau hyperphosphorylation was decreased in vivo because of ELF-MF exposure, and this decrease was induced by the inhibition of GSK3β and CDK5 activities and activation of PP2Ac. We are the first to report that exposure to ELF-MF can attenuate tau phosphorylation. These findings suggest that ELF-MF exposure could act as a valid therapeutic strategy for ameliorating cognitive deficits and attenuating tau hyperphosphorylation in AD.
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441
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Bonutti F, Tecchio M, Maieron M, Trevisan D, Negro C, Calligaris F. Measurement of the weighted peak level for occupational exposure to gradient magnetic fields for 1.5 and 3 Tesla MRI body scanners. RADIATION PROTECTION DOSIMETRY 2016; 168:358-364. [PMID: 25987585 DOI: 10.1093/rpd/ncv308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 03/27/2015] [Indexed: 06/04/2023]
Abstract
The purpose of this work is to give a contribution to the construction of a comprehensive knowledge of the exposure levels to gradient magnetic fields (GMF) in terms of the weighed peak (WP), especially for 3 Tesla scanners for which there are still few works available in the literature. A new generation probe for the measurement of electromagnetic fields in the range of 1 Hz-400 kHz was used to assess the occupational exposure levels to the GMF for 1.5 and 3.0 Tesla MRI body scanners, using the method of the WP according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) approach. The probe was placed at a height of 1.1 m, close to the MRI scanners, where operators could stay during some medical procedures with particular issues. The measurements were performed for a set of typical acquisition sequences for body (liver) and head exams. The measured values of WP were in compliance with ICNIRP 2010 reference levels for occupational exposures.
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Affiliation(s)
- F Bonutti
- Medical Physics Department, Academic Hospital 'S.Maria della Misericordia', Udine, Italy
| | - M Tecchio
- Faculty of Medicine, School for Radiographers, University of Udine, Udine, Italy
| | - M Maieron
- Medical Physics Department, Academic Hospital 'S.Maria della Misericordia', Udine, Italy
| | - D Trevisan
- Medical Physics Department, S. Chiara Hospital, APSS Trento, Trento, Italy
| | - C Negro
- Occupational Medicine Department, University of Trieste, Trieste, Italy
| | - F Calligaris
- Department of Physics, University of Trieste, Trieste, Italy
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442
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Romeo S, Sannino A, Scarfì MR, Massa R, d’Angelo R, Zeni O. Lack of effects on key cellular parameters of MRC-5 human lung fibroblasts exposed to 370 mT static magnetic field. Sci Rep 2016; 6:19398. [PMID: 26762783 PMCID: PMC4725921 DOI: 10.1038/srep19398] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/07/2015] [Indexed: 01/22/2023] Open
Abstract
The last decades have seen increased interest toward possible adverse effects arising from exposure to intense static magnetic fields. This concern is mainly due to the wider and wider applications of such fields in industry and clinical practice; among them, Magnetic Resonance Imaging (MRI) facilities are the main sources of exposure to static magnetic fields for both general public (patients) and workers. In recent investigations, exposures to static magnetic fields have been demonstrated to elicit, in different cell models, both permanent and transient modifications in cellular endpoints critical for the carcinogenesis process. The World Health Organization has therefore recommended in vitro investigations as important research need, to be carried out under strictly controlled exposure conditions. Here we report on the absence of effects on cell viability, reactive oxygen species levels and DNA integrity in MRC-5 human foetal lung fibroblasts exposed to 370 mT magnetic induction level, under different exposure regimens. Exposures have been performed by using an experimental apparatus designed and realized for operating with the static magnetic field generated by permanent magnets, and confined in a magnetic circuit, to allow cell cultures exposure in absence of confounding factors like heating or electric field components.
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Affiliation(s)
- Stefania Romeo
- CNR – Institute for Electromagnetic Sensing of Environment, Via Diocleziano 328, 80124 Naples, Italy
| | - Anna Sannino
- CNR – Institute for Electromagnetic Sensing of Environment, Via Diocleziano 328, 80124 Naples, Italy
| | - Maria Rosaria Scarfì
- CNR – Institute for Electromagnetic Sensing of Environment, Via Diocleziano 328, 80124 Naples, Italy
| | - Rita Massa
- CNR – Institute for Electromagnetic Sensing of Environment, Via Diocleziano 328, 80124 Naples, Italy
- Department of Physics, University of Naples Federico II, CMSA via Cintia, 80126, Napoli, Italy
| | - Raffaele d’Angelo
- Italian Workers’ Compensation Authority (INAIL)–Regional Technical Advisory Department Risk and Prevention Assessment (CONTARP) of Campania, via Nuova Poggioreale, 80143 Napoli
| | - Olga Zeni
- CNR – Institute for Electromagnetic Sensing of Environment, Via Diocleziano 328, 80124 Naples, Italy
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443
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Yoshie S, Ogasawara Y, Ikehata M, Ishii K, Suzuki Y, Wada K, Wake K, Nakasono S, Taki M, Ohkubo C. Evaluation of biological effects of intermediate frequency magnetic field on differentiation of embryonic stem cell. Toxicol Rep 2016; 3:135-140. [PMID: 28959531 PMCID: PMC5615788 DOI: 10.1016/j.toxrep.2015.12.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/29/2015] [Accepted: 12/30/2015] [Indexed: 01/05/2023] Open
Abstract
The embryotoxic effect of intermediate frequency (IF) magnetic field (MF) was evaluated using murine embryonic stem (ES) cells and fibroblast cells based on the embryonic stem cell test (EST). The cells were exposed to 21 kHz IF-MF up to magnetic flux density of 3.9 mT during the cell proliferation process (7 days) or the cell differentiation process (10 days) during which an embryonic body differentiated into myocardial cells. As a result, there was no significant difference in the cell proliferation between sham- and IF-MF-exposed cells for both ES and fibroblast cells. Similarly, the ratio of the number of ES-derived cell aggregates differentiated to myocardial cells to total number of cell aggregates was not changed by IF-MF exposure. In addition, the expressions of a cardiomyocytes-specific gene, Myl2, and an early developmental gene, Hba-x, in the exposed cell aggregate were not altered. Since the magnetic flux density adopted in this study is much higher than that generated by an inverter of the electrical railway, an induction heating (IH) cooktop, etc. in our daily lives, these results suggested that IF-MF in which the public is exposed to in general living environment would not have embryotoxic effect.
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Key Words
- 5-FU, 5-fluorouracil
- Differentiation
- EB, embryonic body
- ELF, extremely low frequency
- EMF, electromagnetic field
- ES, embryonic stem
- EST, embryonic stem cell test
- Embryonic stem cell
- Gene expression
- ICNIRP, International Commission of Non-Ionizing Radiation Protection
- IF, intermediate frequency
- IH, induction heating
- Intermediate frequency magnetic field
- MF, magnetic field
- RF, radiofrequency
- WHO, World Health Organization
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Affiliation(s)
- Sachiko Yoshie
- Biotechnology Laboratory, Human Science Division, Railway Technical Research Institute, 2-8-38, Hikari-cho, Kokubunji, Tokyo 185-8540, Japan
| | - Yuki Ogasawara
- Hygienic Chemistry, Health and Environmental Sciences, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose-shi, Tokyo 204-8588, Japan
| | - Masateru Ikehata
- Biotechnology Laboratory, Human Science Division, Railway Technical Research Institute, 2-8-38, Hikari-cho, Kokubunji, Tokyo 185-8540, Japan
| | - Kazuyuki Ishii
- Hygienic Chemistry, Health and Environmental Sciences, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose-shi, Tokyo 204-8588, Japan
| | - Yukihisa Suzuki
- Faculty of Electrical & Electronic Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan
| | - Keiji Wada
- Faculty of Electrical & Electronic Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan
| | - Kanako Wake
- Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, 4-2-1, Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan
| | - Satoshi Nakasono
- EMF Environment Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko-shi, Chiba 270-1194, Japan
| | - Masao Taki
- Faculty of Electrical & Electronic Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan
| | - Chiyoji Ohkubo
- Japan EMF Information Center, 2-9-11 Shiba, Minato-ku, Tokyo 105-0014, Japan
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444
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Stippick TW, Sheller MR. Combined magnetic fields provide robust coverage for interbody and posterolateral lumbar spinal fusion sites. Med Biol Eng Comput 2016; 54:113-22. [PMID: 26044553 PMCID: PMC4779460 DOI: 10.1007/s11517-015-1319-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 05/21/2015] [Indexed: 11/29/2022]
Abstract
Electromagnetic fields generated by spinal bone growth stimulation devices have been computationally modelled to determine coverage of the lumbar spinal vertebrae. The underlying assumption of these models was that the electric field, but not the magnetic field, was therapeutically relevant. However, there are no published studies examining the therapeutic coverage of spinal fusion sites by stimulators utilizing combined magnetic fields. To assess the coverage, an anatomical model of the vertebrae and discs of the lumbar spine was developed to represent interbody and posterolateral fusion sites. Computer simulations of the induced electromagnetic fields were analysed to determine coverage of the fusion sites. For both interbody and posterolateral fusion models, combined magnetic fields provided 100% coverage of the fusion sites for all intervertebral disc spaces and for all posterior planes from L1 to L5, respectively. Within the vertebral column, the magnitude of the electric field reached a maximum value of 3.6 × 10(-4) V/m, which is several orders of magnitude less than any reported study demonstrating a biological effect. Given its clinical efficacy, a bone growth stimulator utilizing combined magnetic fields must rely on the action of its magnetic field rather than its electric field for a therapeutic effect.
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445
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Boulant N, Wu X, Adriany G, Schmitter S, Uğurbil K, Van de Moortele PF. Direct control of the temperature rise in parallel transmission by means of temperature virtual observation points: Simulations at 10.5 Tesla. Magn Reson Med 2016; 75:249-56. [PMID: 25754685 PMCID: PMC4561040 DOI: 10.1002/mrm.25637] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 12/19/2014] [Accepted: 01/07/2015] [Indexed: 11/11/2022]
Abstract
PURPOSE A method using parallel transmission to mitigate B1+ inhomogeneity while explicitly constraining the temperature rise is reported and compared with a more traditional SAR-constrained pulse design. METHODS Finite difference time domain simulations are performed on a numerical human head model and for a 16-channel coil at 10.5 Tesla. Based on a set of presimulations, a virtual observation point compression model for the temperature rise is derived. This compact representation is then used in a nonlinear programming algorithm for pulse design under explicit temperature rise constraints. RESULTS In the example of a time-of-flight sequence, radiofrequency pulse performance in some cases is increased by a factor of two compared with SAR-constrained pulses, while temperature rise is directly and efficiently controlled. Pulse performance can be gained by relaxing the SAR constraints, but at the expense of a loss of direct control on temperature. CONCLUSION Given the importance of accurate safety control at ultrahigh field and the lack of direct correspondence between SAR and temperature, this work motivates the need for thorough thermal studies in normal in vivo conditions. The tools presented here will possibly contribute to safer and more efficient MR exams.
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Affiliation(s)
- Nicolas Boulant
- CEA, DSV, I2BM, NeuroSpin, Unirs, Gif sur Yvette 91191, France
| | - Xiaoping Wu
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
| | - Gregor Adriany
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sebastian Schmitter
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kamil Uğurbil
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
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446
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Lai J, Zhang Y, Zhang J, Liu X, Ruan G, Chaugai S, Tang J, Wang H, Chen C, Wang DW. Effects of 100-μT extremely low frequency electromagnetic fields exposure on hematograms and blood chemistry in rats. JOURNAL OF RADIATION RESEARCH 2016; 57:16-24. [PMID: 26404558 PMCID: PMC4708915 DOI: 10.1093/jrr/rrv059] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/03/2015] [Accepted: 08/14/2015] [Indexed: 05/11/2023]
Abstract
The aim of this study was to test whether extremely low frequency electromagnetic fields (ELF EMFs) affect health or not. Here, we constructed a 100-μT/50 Hz electromagnetic field atmosphere. A total of 128 rats were randomly assigned into two groups: the ELF EMF group and the sham group. The ELF EMF group was exposed to 100-μT/50-Hz ELF EMF for 20 h per day for three months; at the same time the other group was exposed to a sham device without ELF EMF. During the three months, the weight was recorded every 2 weeks, and the water intake and food intake of the animals were recorded weekly. The hematologic parameters were detected before and after the exposure, whereas blood chemistry analysis was performed every 4 weeks. The general condition of the exposed rats was not affected by ELF EMF. Compared with the sham group, the hematograms were not significantly altered in the ELF EMF group. Similarly, the blood chemistry (including lipid profile, blood glucose, liver function and renal function of rats) from the ELF EMF group showed no difference compared with rats from the control group during the three months exposure. The present study indicated that short-term exposure of 100-μT/50-Hz ELF EMF may not affect hematograms and blood chemistry in rats.
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Affiliation(s)
- Jinsheng Lai
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Yemao Zhang
- High Voltage Research Institute, China Electric Power Research Institute, Wuhan, 430074, People's Republic of China
| | - Jiangong Zhang
- High Voltage Research Institute, China Electric Power Research Institute, Wuhan, 430074, People's Republic of China
| | - Xingfa Liu
- High Voltage Research Institute, China Electric Power Research Institute, Wuhan, 430074, People's Republic of China
| | - Guoran Ruan
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Sandip Chaugai
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Jiarong Tang
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Hong Wang
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Chen Chen
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
| | - Dao Wen Wang
- Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan,430030, People's Republic of China
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447
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Lewis RC, Hauser R, Maynard AD, Neitzel RL, Wang L, Kavet R, Meeker JD. Exposure to Power-Frequency Magnetic Fields and the Risk of Infertility and Adverse Pregnancy Outcomes: Update on the Human Evidence and Recommendations for Future Study Designs. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2016; 19:29-45. [PMID: 27030583 PMCID: PMC4848457 DOI: 10.1080/10937404.2015.1134370] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Infertility and adverse pregnancy outcomes are significant public health concerns with global prevalence. Over the past 35 years, research has addressed whether exposure to power-frequency magnetic fields is one of the etiologic factors attributed to these conditions. However, no apparent authoritative reviews on this topic have been published in the peer-reviewed literature for nearly 15 years. This review provides an overview and critical analysis of human studies that were published in the peer-reviewed literature between 2002 and July 2015. Using PubMed, 13 epidemiology studies published during this time frame that concern exposure to magnetic fields and adverse prenatal (e.g., miscarriage), neonatal (e.g., preterm birth or birth defects), and male fertility (e.g., poor semen quality) outcomes were identified. Some of these studies reported associations whereas others did not, and study design limitations may explain these inconsistencies. Future investigations need to be designed with these limitations in mind to address existing research gaps. In particular, the following issues are discussed: (1) importance of selecting the appropriate study population, (2) need for addressing confounding due to unmeasured physical activity, (3) importance of minimizing information bias from exposure measurement error, (4) consideration of alternative magnetic field exposure metrics, and (5) implications and applications of personal exposure data that are correlated within female-male couples. Further epidemiologic research is needed, given the near ubiquitous exposures to power-frequency magnetic fields in the general population.
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Affiliation(s)
- Ryan C. Lewis
- University of Michigan School of Public Health, Department of Environmental Health Sciences, 1415 Washington Heights, Ann Arbor, Michigan 48109, USA
- Exponent, Inc., Center for Occupational & Environmental Health Risk Assessment, 475 14 Street, Suite 475, Oakland, California 94612, USA
| | - Russ Hauser
- Harvard T.H. Chan School of Public Health, Departments of Environmental Health and Epidemiology, Building I, 14 Floor, 665 Huntington Avenue, Boston, Massachusetts 02115, USA
- Massachusetts General Hospital, Vincent Memorial Obstetrics and Gynecology Service, 55 Fruit Street, Boston, Massachusetts 02114, USA
| | - Andrew D. Maynard
- University of Michigan School of Public Health, Department of Environmental Health Sciences, 1415 Washington Heights, Ann Arbor, Michigan 48109, USA
| | - Richard L. Neitzel
- University of Michigan School of Public Health, Department of Environmental Health Sciences, 1415 Washington Heights, Ann Arbor, Michigan 48109, USA
| | - Lu Wang
- University of Michigan School of Public Health, Department of Biostatistics, 1415 Washington Heights, Ann Arbor, Michigan 48109, USA
| | - Robert Kavet
- Electric Power Research Institute, 3420 Hillview Avenue, Palo Alto, California 94304, USA
| | - John D. Meeker
- University of Michigan School of Public Health, Department of Environmental Health Sciences, 1415 Washington Heights, Ann Arbor, Michigan 48109, USA
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448
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Racuciu M, Miclaus S, Creanga D. On the thermal effect induced in tissue samples exposed to extremely low-frequency electromagnetic field. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2015; 13:85. [PMID: 26682060 PMCID: PMC4682274 DOI: 10.1186/s40201-015-0241-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 12/13/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND The influence of electromagnetic exposure on mammalian tissues was approached as a public health issue aiming to reveal the putative side effect of 50 Hz industrial and domestic supply source (i) during aliments storage near such sources; (ii) in people staying couple of hours in the proximity of conducting wires. MATERIALS AND METHODS Fluorescence emission based thermal sensor was used to emphasize temperature dynamics of fresh meat samples during controlled electromagnetic exposure in Helmholtz coils adjusted to deliver 50 Hz / (4÷10) mT electromagnetic field in their inner volume. Fluoroptic temperature probe with 0.1 °C accuracy measurement and data acquisition software allowed reading temperature every second, in the tissue volume during exposure. RESULTS The temperature dynamics curves of ex-vivo porcine tissues like liver, kidney, brain, muscle, lung, and bone, were comparatively analyzed - the choosing of the mammalian species being justified by metabolic and physiological similarities with human body. The curve slopes appear to be the same for the range of initial temperatures chosen to perform the tests (20.0 ± 0.1 °C), the temperature increase reaching around 2.0 °C for the magnetic flux density of 10 mT. Quantitative dependence was evidenced between the thermal effect and the magnetic flux density. CONCLUSIONS The technical interpretation is based on heating effect, on bioimpedance increasing and on water vaporization during wet sample exposure. The biomedical aspects derive from the degrading effects of food heating as well as from possible in vivo effects of living body exposure.
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Affiliation(s)
- M. Racuciu
- />Environmental Sciences and Physics Department, Faculty of Sciences in “Lucian Blaga” University, Dr. I. Ratiu Street, no. 5-7, Sibiu, 550024 Romania
| | - S. Miclaus
- />Technical Sciences Department, ”Nicolae Balcescu” Land Forces Academy, Revolutiei Street, no. 3-5, Sibiu, 550170 Romania
| | - D. Creanga
- />Biophysics and Medical Physics Laboratory, Faculty of Physics, “Alexandru Ioan Cuza” University, 11, Blvd. Carol I, Iasi, 700506 Romania
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449
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Huss A, Murbach M, van Moorselaar I, Kuster N, van Strien R, Kromhout H, Vermeulen R, Slottje P. Novel exposure units for at-home personalized testing of electromagnetic sensibility. Bioelectromagnetics 2015; 37:62-8. [PMID: 26661464 DOI: 10.1002/bem.21943] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 10/21/2015] [Indexed: 11/11/2022]
Abstract
Previous experimental studies on electromagnetic hypersensitivity have been criticized regarding inflexibility of choice of exposure and of study locations. We developed and tested novel portable exposure units that can generate different output levels of various extremely low frequency magnetic fields (ELF-MF; 50 Hz field plus harmonics) and radiofrequency electromagnetic fields (RF-EMF). Testing was done with a group of healthy volunteers (n = 25 for 5 ELF-MF and n = 25 for 5 RF-EMF signals) to assess if units were indeed able to produce double-blind exposure conditions. Results substantiated that double-blind conditions were met; on average participants scored 50.6% of conditions correct on the ELF-MF, and 50.0% on the RF-EMF unit, which corresponds to guessing probability. No cues as to exposure conditions were reported. We aim to use these units in a future experiment with subjects who wish to test their personal hypothesis of being able to sense or experience when being exposed to EMF. The new units allow for a high degree of flexibility regarding choice of applied electromagnetic signal, output power level and location (at home or another environment of subjects' choosing).
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Affiliation(s)
- Anke Huss
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.,Institute for Social and Preventive Medicine, Bern, Switzerland
| | | | - Imke van Moorselaar
- Department of Environmental Health, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands
| | | | - Rob van Strien
- Department of Environmental Health, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands
| | - Hans Kromhout
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Roel Vermeulen
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.,Julius Centre for Public Health Sciences and Primary Care, University Medical Centre, Utrecht, The Netherlands
| | - Pauline Slottje
- Department of General Practice and Elderly Care Medicine, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
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450
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Chan KH, Ohta S, Laakso I, Hirata A, Suzuki Y, Kavet R. Computational dosimetry for child and adult human models due to contact current from 10 Hz to 110 MHz. RADIATION PROTECTION DOSIMETRY 2015; 167:642-652. [PMID: 25344888 DOI: 10.1093/rpd/ncu322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 09/26/2014] [Indexed: 06/04/2023]
Abstract
This study computationally investigates in situ electric field due to low-frequency contact current and specific absorption rate (SAR) due to high-frequency contact currents in a realistic child model and compared with those in the adult model. The in situ electric fields and SAR in the child model are found to exceed the corresponding values in the adult. At the finger tip, the electric field and SAR due to contact currents, both at the ICNIRP reference levels and IEEE Maximum Permissible Exposures, are well beyond the corresponding basic restrictions. In the remaining part, the largest difference was observed in spinal tissue, and the smallest effect was in the heart. With respect to brain and skin conductivities, one needs to strongly consider which values of tissue properties are used to interpret one's results. The in situ electric fields resulting from contact with the metal plane are similar to those for contact with the wire.
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Affiliation(s)
- Kwok Hung Chan
- Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya-shi 466-8555, Japan City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China
| | - Shunya Ohta
- Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya-shi 466-8555, Japan
| | - Ilkka Laakso
- Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya-shi 466-8555, Japan
| | - Akimasa Hirata
- Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya-shi 466-8555, Japan
| | | | - Robert Kavet
- Electric Power Research Institute, Palo Alto, CA, USA
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