Bioelectromagnetics29:363^370(2008) SetupandDosimetryforExposing AnaesthetisedPigsInVivoto900MHzGSM Mobile Phone Fields Tommi Toivonen, 1 * TimToivo, 1 Risto Pitka«aho, 2 Lauri Puranen, 1 Minna Silfverhuth, 3 Ari Mennander, 4 Markus Hannula, 5 Jari Hyttinen, 5 and Kari Jokela 1 1 STUKöRadiationandNuclearSafetyAuthority,Helsinki,Finland 2 VTT,TechnicalResearchCentreofFinland,Espoo,Finland 3 DepartmentofDiagnosticRadiology,UniversityofOulu,Oulu,Finland 4 HeartCenter,DepartmentofCardiacSurgery,TampereUniversityHospital, Tampere,Finland 5 RGI,TampereUniversityofTechnology,Tampere,Finland The aim of this study was a dosimetrical analysis of the setup used in the exposure of the heads of domestic pigs to GSM-modulated radio frequency electromagnetic fields (RF-EMF) at 900 MHz. The heads of pigs were irradiated with a half wave dipole using three different exposure routines; short bursts of 1–3 s at two different exposure levels and a continuous 10-min exposure. The electroencephalogram (EEG) was registered continuously during the exposures to search for RF-EMF originated changes. The dosimetry was based on simulations with the anatomical heterogeneous numerical model of the pig head. The simulation results were validated by experimental measurements with the exposure dipole and a homogeneous liquid phantom resembling the pig head. The specific absorption rate (SAR), defined as a maximum average over 10 g tissue mass (SAR 10g ), was 7.3 W/kg for the first set of short bursts and 31 W/kg for the second set of short bursts. The SAR 10g in the continuous 10-min exposure was 31 W/kg. The estimated uncertainty for the dosimetry was 25% (K ¼ 2). Bioelectromagnetics 29:363–370, 2008. ß 2008 Wiley-Liss, Inc. Key words: electroencephalogram (EEG); anatomical numerical model; finite difference time domain (FDTD) simulation; high exposure level INTRODUCTION The health effects of radio frequency electro- magnetic fields (RF-EMF) from mobile phones have been studied extensively since the technology was widely adopted in the 1990s. Indications of the RF- EMF originated changes in biological systems have been researched by exposing human volunteers, animals and cells to radio frequency (RF) fields as well as by performing epidemiological studies [Juutilainen and de Seze, 1998; Jauchem et al., 2000; NRPB, 2003; Lo ¨ nn et al., 2005; Heikkinen et al., 2006; Lahkola et al., 2006]. Human volunteer studies have been performed to find acute effects in brain activity or subjective symptoms caused by mobile phone use [Hietanen et al., 2002; Krause et al., 2004]. The outcome of these studies does not support the existence of effects caused by RF-EMF from mobile phones. However, the limitation of these studies is the restricted exposure level due to the safety of volunteers. The primary purpose of this in vivo experimental setup was to study whether the acute effects in brain functions can be seen using significantly higher specific absorption rates (SAR) than can be used with human volunteers. Therefore, three independent exposures were performed for a total of 11 anaesthetised domestic pigs and the head of each pig was exposed to GSM (global system for mobile communication) signal at 890 MHz. The first exposure consisted of several short (1–3 s) pulses at a SAR level of 7.3 W/kg defined as a maximum average of 10 g of tissue (SAR 10g ). The ß 2008Wiley-Liss,Inc. —————— Grant sponsor: The Finnish Research Programme HERMO (Health Risk Assessment of Mobile Communications). *Correspondence to: Tommi Toivonen, STUK—Radiation and Nuclear Safety Authority, Laippatie 4/BOX 14, FIN-00881 Helsinki, Finland. E-mail: tommi.toivonen@stuk.fi Received for review 21 September 2007; Final revision received 8 November 2007 DOI 10.1002/bem.20404 Published online 4 February 2008 in Wiley InterScience (www.interscience.wiley.com).