First Place Platform presentation (5-2):
EVALUATION OF ARTIFACTS BY EEG ELECTRODES DURING RF EXPOSURES.
Co-authors: M. Murbach1,3, S. Kuehn1,3, M. Christopoulou1,2,
A. Christ1, P. Achermann4, N. Kuster1; 1IT’IS Foundation, Zurich, Switzerland, 2Biomedical Simulations and Imaging Lab, Nat’l Tech Univ, Athens, Greece, 3Swiss Federal Inst of Tech (ETH), Zurich, Switzerland. 4Inst of Pharmacology and Toxicology,Univ of Zurich, Zurich, Switzerland
EMF Risk and Exposure Assessments
The initial projects of Manuel Murbach’s PhD studies at the IT’IS Foundation comprise developing novel exposure systems for biomedical research as well as improving/enhancing our current systems. Highlights include novel RF exposure assessments for the C.elegans nematode on AGAR substrate (BioEM 2009 poster), and human epidermis layers on dermis samples to GSM900 signals
in vitro, as well as human exposure to higher carrier frequencies and highly pulsed signals in vivo (BioEM 2009 poster and platform). The human sleep studies (currently conducted within the Swiss National Research Program, NFP57) will be enhanced this year for ELF magnetic field exposure of the subjects’ heads. The intention is to compare the effects of RF exposure with exposure to
the ELF-pulsed magnetic signals that are identical to the modulation envelopes of the RF exposure.
The second part of his PhD research will focus on exposure assessment in clinical MRI environments. The goal of our ambitious project MRI+ is to derive scientifically sound guidelines/standards with respect to RF exposure for the safe operation of MR scanners (1, 1.5 and 3T) for patients with and without implants. This is necessary as the generally applicable international safety guidelines for RF exposure are exceeded during normal MR investigations and interventional operations. In order to operate the system beyond the established protocols/limits, novel procedures, testing and validations techniques must be developed. The various objectives of the project range from the development of comprehensive patient modelsthrough to the development of scanning parameter guidelines for the various classes of MRI scanners to optimize benefits/risks in MRI applications for patients and to prevent risks for workers.
2nd Place Platform Presentation (1-2):
HYBRID SAR ANALYSIS OF VARIOUS HUMAN MODELS IN FRONT OF BASE STATION ANTENNAS IN THE FREQUENCY RANGE FROM 300 MHZ TO 5000 MHZ.
Co-authors: M. Gosselin2, V. Kellerman3, G. Vermeeren4, S. Benkler5, S. Kuehn1,2, A. Hadjem6, A. Gati6, W. Joseph4, M. Wong6, J. Wiart6, F. J. Meyer3, L. Martens4, N. Kuster1,2; 1BioEM Group, Integrated Systems Laboratory, ETH Zurich, Zurich, Switzerland. 2IT’IS Foundation, Zurich, Switzerland. 3EMSS, Stellenbosch, South Africa. 4INTEC, Ghent University /IBBT, Ghent, Belgium. 5SPEAG, Zurich, Switzerland. 6Orange Labs (FT RD), Paris, France.
Marie-Christine’s initial research at the IT’IS Foundationis focused on compliance with safety limits of human exposure to mobile phones and base station antennas. In particular, this includes numerical and experimental assessment of the interaction mechanisms between electromagnetic fields and biological tissues, as well as evaluation of the temperature increase caused by absorbed energy.
A recent project presented at the 2009 Joint BEMS and EBEA Meeting entitled “Hybrid SAR Analysis of Various Human Models in Front of Base Station Antennas in the Frequency Range from 300MHz to 5000MHz’’ has been realized to assist the International Electrotechnical Commission (IEC) in the elaboration of a new international standard regarding exposure to base station antennas and was funded by the MMF/GSMA. A set of formulae has been developed to estimate the whole-body average SAR and peak spatial average SAR in human bodies exposed to base station antennas. These equations, based on physical considerations and on plane-wave simulations using anatomical human body models, are mainly dependant on the dimensions of the human body and the size and radiating properties of the antenna. Exhaustive simulations have been performed in order to validate the SAR estimation equations.
3rd Place Platform Presentation (15-2):
EFFECTS OF A 60 HZ, 3000 MICROTESLA MAGNETIC FIELD ON HUMAN COGNITIVE PROCESSING: PRELIMINARY RESULTS.
Coauthors: Michael Corbacio1,2, Alexandre G. Legros1,2, Anne Beuter3, Julie Weller1, Stephanie Dubois1, Samantha Brown1, Daniel Goulet4, Jacques Lambrozo5, Michel Plante4, Martine Souques5, Frank S. Prato1,2, and Alex W. Thomas1,2; 1Bioelectromagnetics, Imaging Program, LHRI, London, ON, Canada. 2Dept of Medical Biophysics, Univ of Western Ontario, London, ON, Canada. 3Bio-electromagnetisme, IMS, CNRS, Bordeaux, France. 4Lignes, cebles et environnement, Hydro- Quebec, Montreal, QC, Canada. 5Service des Etudes Medicales, EDF, Paris, France.
Michael Corbacio began work on a Master’s degree in Medical Biophysics at the University of Western Ontario under the joint supervision of Drs. Alexandre Legros and Alex Thomas in September 2008. At BioEM 2009, Michael presented this ongoing project in which participants were recruited to perform select validated psychometric tests. He did this to determine if there are any detectable
effects from exposure to a 60 Hz, 3000 μT magnetic field (MF) on human cognitive performance. The frequency of the MF being studied (60 Hz) is the same as the North American power-line distribution system. This research builds on the previous work of his lab which presented material on the neurobehavioural effects of exposure to a 60 Hz, 1800 μT MF at earlier meetings.
Individuals participating in the double-blind counterbalanced protocol came into the lab for two different sessions. The first session (which never has a MF exposure) established baseline values of anxiety, depression, and intelligence through the participant’s performance of the Beck Anxiety Inventory, Beck Depression Inventory-II, and Wechsler Adult Intelligence Scale. The second session
(held on a later date) is when the MF exposure may or may not occur. During this session the participant performed two blocks of testing each preceded by a 30 minute rest period. Each testing block consists of the following psychometric tests performed in the same sequence: Digit Symbol Encoding, Block Design, Arithmetic, Digit Span, Trail Making Test A & B, Stroop, Mental Rotation, and Fitts’ Motor Task. When present the MF exposure was continuous and lasted for 1 hour either during the first rest period and testing block or during the second rest period and testing block. The homogeneous region of MF exposure is centered at the level of the participants’ head and is produced by a whole-body Helmholtz-like coil system.
In preparation for BioEM 2009, the results of 36 participants were analyzed. At the completion of the study at least 99 participants will have been tested. The preliminary results of the Stroop, Mental Rotation, and Fitts’ tasks were reported at the conference and they did not show any significant effect of the MF exposure on performance. This suggests that 1 hour of exposure to a 60 Hz, 3000μT MF does not modulate the cognitive processes involved in the Stroop (selective attention), Mental Rotation (mental imagery rotation), or Fitts’ (perceptivomotor control) tasks. In future work, MF exposure and task induced brain activation will be further investigated using functional Magnetic Resonance Imaging.
4th Place Platform Presentation (17-4):
DEVELOPMENT OF A PREDICTIVE MODEL FOR PERSONAL RF-EMF EXPOSURE
Co-authors: P. Frei1,2, E. Mohler1,2, A Bürgi3, G. Neubauer4, A. Hettich5, G. Theis5, J. Fröhlich6, C. Braun-Fahrländer2, M. Egger1, M. Röösli1,2; 1Inst of Social and Preventive Medicine, Univ of Bern, Bern, Switzerland. 2Inst of Social and Preventive Medicine, Univ of Basel, Basel, Switzerland. 3ARIAS umwelt. forschung.beratung, Bern, Switzerland. 4Smart Systems Division, Austrian Research Centers GmbH, Seibersdorf, Austria. 5Air Quality Management Agency of Basel, Basel, Switzerland. 6Laboratory for Electromagnetic Fields and Microwave Electronics, ETH Zurich, Zurich, Switzerland.
Patrizia Frei presented a prediction model for personal radio frequency electromagnetic field exposure (RF-EMF), which is part of the QUALIFEX study (Health related quality of life and radio frequency electromagnetic field exposure: prospective cohort study). The QUALIFEX project aims at measuring and modeling exposure of a general population sample to different RF-EMF sources. It addresses the question of whether RF-EMF exposure under real life conditions can cause symptoms or impair health-related quality of life.
In the first part of the QUALIFEX project, the exposimeter study, Patrizia collected personal measurements and corresponding diary data from 166 study participants living in Basel (Switzerland) and surroundings. These volunteers carried a personal exposure meter (exposimeter) measuring 12 different frequency bands and filled in a questionnaire on potential exposure relevant factors. In addition, RF-EMF from fixed site transmitters (mobile phone base stations and broadcast transmitters) was modeled at the homes of the study participants by means of a geospatial propagation model which was developed within the QUALIFEX framework (Bürgi et al., 2008). For a validation study, the exposure measurements of 31 study participants were repeated during a second week’s period. Mean exposure levels over all frequency bands were 0.22 V/m, ranging from 0.07 V/m to 0.58 V/m (Frei et al., 2009). Exposure was mainly due to mobile phone handsets, mobile phone base stations and DECT cordless phones and was highest in public transports and at airports.
Based on the data collected in the exposimeter study, Patrizia developed a prediction model for personal RF-EMF exposure. Relevant exposure predictors, which were identified by means of multiple regression analysis, were the modeled RF-EMF at the participants’ home from the propagation model, housing characteristics, ownership of communication devices (wireless LAN, mobile and cordless phones) and behavioral aspects such as amount of time spent in public transports. The validation study showed that the model can also be used to assess average exposure over several months. The exposure prediction model will be applied to a larger study population of approximately
1400 randomly selected study participants in order to investigate possible health effects from RF-EMF exposure in everyday life.
Bürgi, A., Theis, G., Siegenthaler, A., Röösli, M., 2008. Exposure modeling of high-frequency electromagnetic fields. J Expo Sci Environ Epidemiol 18, 183-191.
Frei, P., Mohler, E., Neubauer, G., Theis, G., Burgi, A.,Frohlich, J., et al., 2009. Temporal and spatial variability of personal exposure to radio frequency electromagnetic fields. Environ Res 109, 779-785.