NEWS
Nov 11, 2022
PUBLICATIONS

Mechanism of Capacitive Coupling of Proximal Electromagnetic Sources with Biological Bodies

Andreas Christ, Arya Fallahi, Esra Neufeld, Quirino Balzano, and Niels Kuster, Bioelectromagnetics 2022, Volume 43, Issue 7, pp. 404-412, online 06 November 2022; doi: 10.1002/bem.22422

In this study, we investigate the absorption of the electric (E-) field induced in homogeneous biological tissue exposed to highly localized field sources, such as the charged tips of antennas, in proximity to the body, where E-field coupling dominates. These conditions are relevant for compliance testing of modern mobile phones, for which exposure is evaluated under conditions of a small separation between the radiator and the body. We derive an approximation that characterizes the decay of the induced E-field in the tissue as a function of distance. The absorption is quantified in terms of the local specific absorption rate (SAR) at the tissue surface as a function of the charge at the antenna tip. The approximation is based on the analytical evaluation of the E-fields of a charged disk under quasi-static conditions. We validate this approximation using full-wave simulations of dipoles. We demonstrate that the coupling mechanism of the E-field is dominated by the perpendicular field component, and that wave propagation need not be considered for the characterization of the exposure. The surface SAR decreases approximately with the 4th power of the distance and with the square of the ratio of the permittivities of the tissue and free-space. The approximation allows the induced maximum E-field to be predicted with an accuracy of better than 1.5 dB.

The scientific and technical impact of the study can be summarized as:

  • Capacitive coupling is dominant for electrically small antenna elements located close to the exposed tissue, whereas inductive coupling dominates at distances of a few millimeters or more
  • The attenuation of the capacitively coupled E-fields in the tissue reaches the 4th power of the distance and is significantly higher than that of inductive coupling
  • In the tissue, the amplitude of the perpendicular incident E-field is reduced by up to 60 dB in the extremely low frequency range because of the large contrast in dielectric properties of the tissue compared to free space
  • For applications operating in the low MHz range, such as wireless chargers, exposure due to capacitive coupling is negligible due to the high dielectric contrast, and inductive coupling is dominant
Other News

Mar 1, 2006

 

Mobile Phone Affects Cerebral Blood Flow in Humans

Sargo Aalto, Christian Haarala, Anna Brück, Hannu Sipilä, Heikki Hämäläinen, and Juha O Rinne, in Journal of Cerebral Blood Flow & Metabolism, Volume 26, Number 7, pp. 885–890, July 2006

 
Other News

Mar 1, 2006

 

Cellular Phones, Cordless Phones, and the Risks of Glioma and Meningioma (Interphone Study Group, Germany)

Joachim Schüz, Eva Bohler, Gabriele Berg, Brigitte Schlehofer, Iris Hettinger, Klaus Schlaefer, Jürgen Wahrendorf, Katharina Kunna-Grass, and Maria Blettner, in American Journal of Epidemiology, Volume 163, Issue 6, pp. 512–520, March 2006

 
Other News

Feb 28, 2006

 

Childhood Leukemia and Magnetic Fields in Japan: A Case-control Study of Childhood Leukemia and Residential Power-frequency Magnetic Fields in Japan

Michinori Kabuto, Hiroshi Nitta, Seiichiro Yamamoto, Naohito Yamaguchi, Suminori Akiba, Yasushi Honda, Jun Hagihara, Katsuo Isaka, Tomohiro Saito, Toshiyuki Ojima, Yosikazu Nakamura, Tetsuya Mizoue, Satoko Ito, Akira Eboshida, Shin Yamazaki, Shigeru Sokejima, Yoshika Kurokawa, and Osami Kubo, in International Journal of Cancer, Volume 119, Issue 3, Pages 643–650, August 2006

 
PUBLICATIONS

Feb 8, 2006

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nk@itis.swiss

 

Effects of 900 MHz GSM Wireless Communication Signals on DMBA-Induced Mammary Tumors in Rats

Da Yu, Yonghao Shen, Niels Kuster, Yiti Fu, and Huai Chiang, in Radiation Research, Volume 165, Number 2, pp. 174–180, February 2006

 

 
PRESS

Jan 24, 2006

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nk@itis.swiss

 

EMF Health Risk Research at Monte Verità, Switzerland

The conference summary as well as the presentations of the Monte Verità conference on EMF health risk research are now available on the Monte Verità website (under "results").

 
PUBLICATIONS

Dec 1, 2005

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nk@itis.swiss

 

Nonuniform Grids, Nonorthogonal Grids, Unstructured Grids, and Subgrids, and Antennas

Nicolas Chavannes and others, in “Computational Electrodynamics: The Finite-Difference Time-Domain Method, Third Edition,” Allen Taflove and Susan C. Hagness, Artech House, Inc., Boston, 2005

 

 
MAJOR EVENTS

Nov 20, 2005

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nk@itis.swiss

 

EMF Health Risk Research: Lessons Learned and Recommendations for the Future

A workshop to bring together the most experienced and independent researchers worldwide to develop a vision towards improving the quality of future research on EMF and health.

 
PUBLICATIONS

Oct 31, 2005

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nk@itis.swiss

 

Response, Thermal Regulatory Threshold and Thermal Breakdown Threshold of Restrained RF-Exposed Mice at 905 MHz

Sven Ebert, Sang-Jin Eom, Jürgen Schuderer, U. Apostel, Thomas Tillmann, Clemens Dasenbrock and Niels Kuster, in Physics in Medicine & Biology, Volume 50, Number 21, pp. 5203–5215, October 2005

 

 
Other News

Oct 3, 2005

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nk@itis.swiss

 

New Study on aging effects of the absorption of electromagnetic radiation in the head

A study investigating the electromagnetic energy absorption and possible induced thermal stress considering worst case conditions of age dependent tissue properties, anatomical changes and thermal regulation

 
PUBLICATIONS

Oct 1, 2005

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nk@itis.swiss

 

Effects of 1-Week and 6-Week Exposure to GSM/DCS Radiofrequency Radiation on Micronucleus Formation in B6C3F1 Mice

Bernd-D. Görlitz, Meike Müller, Sven Ebert, Hartmut Hecker, Niels Kuster, and Clemens Dasenbrock, in Radiation Research, Volume 164, Number 4 pt 1, pp. 431–439, October 2005

 

 
Other News

Aug 30, 2005

 

Mobile Phone Use and Risk of Acoustic Neuroma: Results of the Interphone Case-control Study in Five North European Countries

M J Schoemaker, A J Swerdlow, A Ahlbom, A Auvinen, K G Blaasaas, E Cardis, H Collatz Christensen, M Feychting, S J Hepworth, C Johansen, L Klæboe, S Lönn, P A McKinney, K Muir, J Raitanen, T Salminen, J Thomsen and T Tynes, in British Journal of Cancer, Volume 93, Number 7, 842–848, October 2005

 
PUBLICATIONS

Aug 30, 2005

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nk@itis.swiss

 

Differences in RF Energy Absorption in the Heads of Adults and Children

Andreas Christ and Niels Kuster, in Bioelectromagnetics, Volume 26, Issue S7, pp. S31–S44, December 2005

 

 
PRESS

Aug 26, 2005

 

IT'IS Site Selected for Advertisement Shooting

Our entrance door was selected by the biggest retailer in Switzerland as a background for shooting their latest advertisement. Curiously, they are promoting mobile phones!

 
Other News

Aug 26, 2005

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oberle@itis.swiss

 

IT’IS new Associate Member of ITU-R Study Group 1 – Spectrum Management

The IT’IS Foundation has become a new Associate Member of the Radiocommunication Sector of the ITU, the International Telecommunication Union within the United Nations System

 
PUBLICATIONS

Aug 26, 2005

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nk@itis.swiss

 

Electromagnetic Fields Affect Transcript Levels of Apoptosis-Related Genes in Embryonic Stem Cell-derived Neural Progenitor Cells

Teodora Nikolova, Jaroslaw Czyz, Alexandra Rolletschek, Przemyslaw Blyszczuk, Jörg Fuchs, Gabriele Jovtchev, Jürgen Schuderer, Niels Kuster, and Anna M. Wobus, in The FASEB Journal, Volume 19, Number 12, pp. 1686–1688, October 2005

 

 
PUBLICATIONS

Jul 6, 2005

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nk@itis.swiss

 

Dosimetric Comparison of the Specific Anthropomorphic Mannequin (SAM) to 14 Anatomical Head Models Using a Novel Definition for the Mobile Phone Positioning

Wolfgang Kainz, Andreas Christ, Tocher Kellom, Seth Seidman, Neviana Nikoloski, Brian Beard and Niels Kuster, in Physics in Medicine and Biology, Volume 50, Number 14, pp. 3423–3445, July 2005

 

 
Other News

Jun 3, 2005

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nk@itis.swiss

 

New study to develop anatomical high resolution models of adults and children

Within the framework of this study, four high resolution computer models of a woman, a man and two children will be developed

 
Other News

Jun 1, 2005

 

Childhood Cancer in Relation to Distance From High Voltage Power Lines in England and Wales: a Case-control Study

Gerald Draper, Tim Vincent, Mary E Kroll, and John Swanson, in BMJ, Volume 330, p.1290, 4 June 2005

 
Other News

Jun 1, 2005

 

Resonance Effects Indicate a Radical-Pair Mechanism for Avian Magnetic Compass

Thorsten Ritz, Peter Thalau, John B. Phillips, Roswitha Wiltschko and Wolfgang Wiltschko, Nature 429, pp. 177-180, May 2004

 
PUBLICATIONS

Jun 1, 2005

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nk@itis.swiss

 

Whole-Body Exposure to 2.45 GHz Electromagnetic Fields Does Not Alter 12-arm Radial-Maze With Reduced Access to Spatial Cues in Rats

Brigitte Cosquer, Niels Kuster and Jean-Christophe Cassel, Behavioural Brain Research, Volume 161, Issue 2, pp. 331–334, June 2005

 

 
PUBLICATIONS

Jun 1, 2005

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nk@itis.swiss

 

Blood–Brain Barrier and Electromagnetic Fields: Effects of Scopolamine Methylbromide on Working Memory After Whole-body Exposure to 2.45 GHz Microwaves in Rats

Brigitte Cosquer, Anne Pereira de Vasconcelos, Jürg Fröhlich and Jean-Christophe Cassel, Behavioural Brain Research, Volume 161, Issue 2, pp. 229–237, June 2005

 

 
Other News

May 20, 2005

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nk@itis.swiss

 

Experimental Phase of the TNO Study Completed

The experimental phase of the TNO study was successfully completed

 
Other News

May 17, 2005

 

Use of Cellular Telephones and Brain Tumour Risk in Urban and Rural Areas

Hardell's newest publication tested the hypothesis of an association between the use of cellular or cordless telephones and the risk for brain tumours in different geographical areas, urban and rural

 
PRESS

Apr 22, 2005

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nk@itis.swiss

 

IT'IS Foundation at the ETH 150 Years Exhibition, Welcome Tomorrow

The IT'IS Foundation presented its research achievements as part of the 150 year anniversary exhibit of the ETH Zurich at the Zurich main train station.

 
ANNUAL REPORTS

Apr 15, 2005

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nk@itis.swiss

 

IT'IS Annual Report 2004

The Annual Report 2004 features key figures for 2004 and overviews of selected projects:

  • Novel Conformal Meshes
  • Mobile Phone Exposure of Children vs Adults
  • Human Studies for Risk Assessment and Hyperthermia
  • Services

 
Other News

Apr 15, 2005

Contact
oberle@itis.swiss

 

Health Support Systems informational brochure

R&D Services in Medical Technology, the Health Support Systems informational brochure is now available as a PDF

 
Other News

Apr 12, 2005

 

Cellular Telephones and Risk for Brain Tumors

H. Collatz Christensen, J. Schüz, M. Kosteljanetz, H. Skovgaard Poulsen, J. D. Boice, Jr, J. K. McLaughlin, and C. Johansen, Neurology, Volume 64, pp. 1189–1195, April 2005

 
PUBLICATIONS

Apr 1, 2005

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nk@itis.swiss

 

Reevaluation and Improved Design of the TEM Cell In Vitro Exposure Unit for Replication Studies

Neviana Nikoloski, Jürg Fröhlich, Theodoros Samaras, Jürgen Schuderer and Niels Kuster, Bioelectromagnetics Vol. 26, Issue 3, pp. 215–224, April 2005

 

 
PUBLICATIONS

Mar 24, 2005

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nk@itis.swiss

 

Exposure to Pulse-Modulated Radio Frequency Electromagnetic Fields Affects Regional Cerebral Blood Flow

R. Huber, V. Treyer, J. Schuderer, T. Berthold, A. Buck, N. Kuster, H. P. Landolt and P. Achermann, European Journal of Neuroscience, Vol. 21, Issue 4, pp. 1000–1006, February 2005

 

 
PUBLICATIONS

Feb 1, 2005

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nk@itis.swiss

 

The Precautionary Principle in the Information Society: Effects of Pervasive Computing on Health and Enviroment

Lorenz Hilty, Siegfried Behrendt, Mathias Binswanger, Arend Bruinink, Lorenz Erdmann, Jürg Fröhlich, Andreas Köhler, Niels Kuster, Claudia Som, and Felix Würtenberger,
TA-Swiss (Center for Technology Assessment) TA46e/2005, 2003. Revised second edition, 2005

 

 
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