title: Acute Exposure to Terrestrial Trunked Radio (TETRA) has effects on the electroencephalogram and electrocardiogram, consistent with vagal nerve stimulation.
abstract: BACKGROUND
  Terrestrial Trunked Radio (TETRA) is a telecommunications system widely used by police and emergency services around the world. The Stewart Report on mobile telephony and health raised questions about possible health effects associated with TETRA signals. This study investigates possible effects of TETRA signals on the electroencephalogram and electrocardiogram in human volunteers.
  
  
  METHODS
  Blinded randomized provocation study with a standardized TETRA signal or sham exposure. In the first of two experiments, police officers had a TETRA set placed first against the left temple and then the upper-left quadrant of the chest and the electroencephalogram was recorded during rest and active cognitive processing. In the second experiment, volunteers were subject to chest exposure of TETRA whilst their electroencephalogram and heart rate variability derived from the electrocardiogram were recorded.
  
  
  RESULTS
  In the first experiment, we found that exposure to TETRA had consistent neurophysiological effects on the electroencephalogram, but only during chest exposure, in a pattern suggestive of vagal nerve stimulation. In the second experiment, we observed changes in heart rate variability during exposure to TETRA but the electroencephalogram effects were not replicated.
  
  
  CONCLUSIONS
  Observed effects of exposure to TETRA signals on the electroencephalogram (first experiment) and electrocardiogram are consistent with vagal nerve stimulation in the chest by TETRA. However given the small effect on heart rate variability and the lack of consistency on the electroencephalogram, it seems unlikely that this will have a significant impact on health. Long-term monitoring of the health of the police force in relation to TETRA use is on-going.
authors.affiliation: Aston Brain Centre, School of Life & Health Sciences, School of Life & Health Sciences, Aston University, Birmingham B4 7ET, UK. Electronic address: a.p.burgess@aston.ac.uk.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Burgess
authors.affiliation: Aston Brain Centre, School of Life & Health Sciences, School of Life & Health Sciences, Aston University, Birmingham B4 7ET, UK.
authors.forename: Nathalie C
authors.initials: NC
authors.lastname: Fouquet
authors.affiliation: Aston Brain Centre, School of Life & Health Sciences, School of Life & Health Sciences, Aston University, Birmingham B4 7ET, UK.
authors.forename: Stefano
authors.initials: S
authors.lastname: Seri
authors.affiliation: Research Institute for Sport & Exercise Sciences. Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool L3 3AF, UK.
authors.forename: Malcolm B
authors.initials: MB
authors.lastname: Hawken
authors.affiliation: MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, St Mary's Campus, London W2 1PG, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Heard
authors.affiliation: Creativ-Ceutical Ltd, The Bank Chambers, 10 Borough High Street, London SE1 9QQ, UK.
authors.forename: David
authors.initials: D
authors.lastname: Neasham
authors.affiliation: Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD 20892-9778, USA.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Little
authors.affiliation: MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, St Mary's Campus, London W2 1PG, UK. Electronic address: p.elliott@imperial.ac.uk.
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
mesh_terms: D000293:Adolescent; D000328:Adult; D004311:Double-Blind Method; D004562:Electrocardiography; D004569:Electroencephalography; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D016495:Police; D011846:Radio Waves; D055536:Vagus Nerve Stimulation; D055815:Young Adult
keywords: Electromagnetic fields; Exposure; Neurophysiological effects; Occupational cohort; Radio frequency