Bioelectromagnetics 29:185 ^ 196 (2008) The Effects of 884 MHz GSM Wireless Communication Signals on Headache and Other Symptoms: An Experimental Provocation Study Lena Hillert, 1,2 * Torbjo« rn —kerstedt, 3 Arne Lowden, 3 Clairy Wiholm, 4,5 Niels Kuster, 6 Sven Ebert, 6 Clementine Boutry, 6 Scott Douglas Moffat, 7,8 Mats Berg, 9 and Bengt Birger Arnetz 4,5 1 Department of Public Health Sciences, Division of Occupational Medicine, Karolinska Institutet, Stockholm, Sweden 2 Department of Occupational and Environmental Health, Stockholm Centre for Public Health, Stockholm, Sweden 3 National Institute for Psychosocial Medicine (IPM), Karolinska Institutet, Stockholm, Sweden 4 Department of Family Medicine and Public Health Sciences, Division of Occupational and Environmental Health,Wayne State University, Detroit, Michigan 5 Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden 6 IT’IS Foundation for Research on Information Technologies in Society, Swiss Federal Institute of Technology (ETH), Zu« rich, Switzerland 7 Institute of Gerontology,Wayne State University, Detroit, Michigan 8 Department of Psychology,Wayne State University, Detroit, Michigan 9 Department of Medical Sciences, Division of Dermatology, Uppsala University Hospital, Uppsala, Sweden Findings from prior studies of possible health and physiological effects from mobile phone use have been inconsistent. Exposure periods in provocation studies have been rather short and personal characteristics of the participants poorly defined. We studied the effect of radiofrequency field (RF) on self-reported symptoms and detection of fields after a prolonged exposure time and with a well defined study group including subjects reporting symptoms attributed to mobile phone use. The design was a double blind, cross-over provocation study testing a 3-h long GSM handset exposure versus sham. The study group was 71 subjects age 18 – 45, including 38 subjects reporting headache or vertigo in relation to mobile phone use (symptom group) and 33 non-symptomatic subjects. Symptoms were scored on a 7-point Likert scale before, after 1 1 = 2 and 2 3 = 4 h of exposure. Subjects reported their belief of actual exposure status. The results showed that headache was more commonly reported after RF exposure than sham, mainly due to an increase in the non-symptom group. Neither group could detect RF exposure better than by chance. A belief that the RF exposure had been active was associated with skin symptoms. The higher prevalence of headache in the non-symptom group towards the end of RF exposure justifies further investigation of possible physiological correlates. The current study indicates a need to better characterize study participants in mobile phone exposure studies and differences between symptom and non-symptom groups. Bioelectromagnetics 29:185–196, 2008. ß 2007 Wiley-Liss, Inc. Key words: electromagnetic fields; mobile phones; radiofrequency ß 2007 Wiley-Liss,Inc. The authors declare they have no competing financial interests. Grant sponsors: Mobile Manufacturers Forum (MMF); Helsinki University acted as firewall (The sponsor had no pre-submission access to results, or any influence on results and conclusions presented in this manuscript). *Correspondence to: Lena Hillert, Department of Occupational and Environmental Health, Norrbacka 3rd floor, SE-17176 Stockholm, Sweden. E-mail: lena.hillert@ki.se —————— Received for review 20 March 2007; Final revision received 3 September 2007 DOI 10.1002/bem.20379 Published online 28 November 2007 in Wiley InterScience (www.interscience.wiley.com).