title: Effects of GSM 900 MHz on middle cerebral artery blood flow assessed by transcranial Doppler sonography.
abstract: Mobile phone use has increased worldwide but its possible effects on the brain remain unclear. The aim of the present study was to investigate the effect of acute exposure to a radio frequency electromagnetic field (RF EMF) generated by a mobile phone operating in the Global System for Mobile Communication (GSM) 900 MHz on cerebral blood flow. Twenty-nine volunteers attended two experimental sessions: a sham exposure session and a real exposure session in a cross-over double-blind study in which a mobile phone was positioned on the left side of the head. In one session, the mobile phone was operated without RF radiation (sham phone) and in the other study it was operated with RF radiation (real phone) for 20 min. Thus, each subject served as its own control. Middle cerebral artery blood flow was monitored noninvasively by transcranial Doppler sonography to measure middle cerebral artery blood flow velocity. Pulsatility index and resistance index were also evaluated. A voluntary breath holding physiological test was carried out as a positive control for testing cerebral vasoreactivity. Hemodynamic variables were recorded and analyzed before, during and after mobile phone exposure. No significant changes were detected in studied variables in middle cerebral arteries during sham or real exposure. In the exposed side the cerebral blood flow velocity, the pulsatility index and the resistance index during sham and real exposure were respectively: [61.9 ± 1.3, 61.7 ± 1.3 cm/s (P = 0.89)]; [0.93 ± 0.03, 0.90 ± 0.02 (P = 0.84)] and [0.58 ± 0.01, 0.58 ± 0.01 (P = 0.96)] at baseline; and [60.6 ± 1.3, 62 ± 1.6 cm/s (P = 0.40)]; [0.91 ± 0.03, 0.87 ± 0.03 (P = 0.97)]; [0.57 ± 0.01, 0.56 ± 0.01 (P = 0.82)] after 20 min of exposure. Twenty minutes of RF exposure to a mobile phone does not seem to affect the cerebral circulation.
authors.affiliation: Institut National de l'Environnement Industriel et des Risques, Department of Experimental Toxicology, BP.2, 60550 Verneuil-en-Halatte, France. rania.ghosn@ineris.fr
authors.forename: Rania
authors.initials: R
authors.lastname: Ghosn
authors.forename: György
authors.initials: G
authors.lastname: Thuróczy
authors.forename: Nathalie
authors.initials: N
authors.lastname: Loos
authors.forename: Valérie
authors.initials: V
authors.lastname: Brenet-Dufour
authors.forename: Sophie
authors.initials: S
authors.lastname: Liabeuf
authors.forename: René
authors.initials: R
authors.lastname: de Seze
authors.forename: Brahim
authors.initials: B
authors.lastname: Selmaoui
mesh_terms: D000328:Adult; D001775:Blood Circulation / Q000528:radiation effects*; D062485:Breath Holding / Q000528:radiation effects; D040421:Cell Phone; D005260:Female; D006339:Heart Rate / Q000528:radiation effects; D006801:Humans; D008297:Male; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging* / Q000502:physiology / Q000528:radiation effects*; D011673:Pulsatile Flow / Q000528:radiation effects; D011846:Radio Waves / Q000009:adverse effects*; D012881:Skin Temperature / Q000528:radiation effects; D017585:Ultrasonography, Doppler, Transcranial; D055815:Young Adult