title: Temporal and spatial variability of personal exposure to radio frequency electromagnetic fields.
abstract: BACKGROUND
  Little is known about the population's exposure to radio frequency electromagnetic fields (RF-EMF) in industrialized countries.
  
  
  OBJECTIVE
  To examine levels of exposure and the importance of different RF-EMF sources and settings in a sample of volunteers living in a Swiss city.
  
  
  METHODS
  RF-EMF exposure of 166 volunteers from Basel, Switzerland, was measured with personal exposure meters (exposimeters). Participants carried an exposimeter for 1 week (two separate weeks in 32 participants) and completed an activity diary. Mean values were calculated using the robust regression on order statistics (ROS) method.
  
  
  RESULTS
  Mean weekly exposure to all RF-EMF sources was 0.13 mW/m(2) (0.22 V/m) (range of individual means 0.014-0.881 mW/m(2)). Exposure was mainly due to mobile phone base stations (32.0%), mobile phone handsets (29.1%) and digital enhanced cordless telecommunications (DECT) phones (22.7%). Persons owning a DECT phone (total mean 0.15 mW/m(2)) or mobile phone (0.14 mW/m(2)) were exposed more than those not owning a DECT or mobile phone (0.10 mW/m(2)). Mean values were highest in trains (1.16 mW/m(2)), airports (0.74 mW/m(2)) and tramways or buses (0.36 mW/m(2)), and higher during daytime (0.16 mW/m(2)) than nighttime (0.08 mW/m(2)). The Spearman correlation coefficient between mean exposure in the first and second week was 0.61.
  
  
  CONCLUSIONS
  Exposure to RF-EMF varied considerably between persons and locations but was fairly consistent within persons. Mobile phone handsets, mobile phone base stations and cordless phones were important sources of exposure in urban Switzerland.
authors.affiliation: Institute of Social and Preventive Medicine, University of Bern, Switzerland.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Frei
authors.forename: Evelyn
authors.initials: E
authors.lastname: Mohler
authors.forename: Georg
authors.initials: G
authors.lastname: Neubauer
authors.forename: Gaston
authors.initials: G
authors.lastname: Theis
authors.forename: Alfred
authors.initials: A
authors.lastname: Bürgi
authors.forename: Jürg
authors.initials: J
authors.lastname: Fröhlich
authors.forename: Charlotte
authors.initials: C
authors.lastname: Braun-Fahrländer
authors.forename: John
authors.initials: J
authors.lastname: Bolte
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
authors.forename: Martin
authors.initials: M
authors.lastname: Röösli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D040421:Cell Phone / Q000592:standards; D003627:Data Interpretation, Statistical; D004574:Electromagnetic Fields / Q000009:adverse effects*; D004781:Environmental Exposure / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011834:Radiation Monitoring / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013557:Switzerland; D055815:Young Adult