title: Symptoms in Swiss adolescents in relation to exposure from fixed site transmitters: a prospective cohort study.
abstract: There is public concern regarding potential health effects of radiofrequency electromagnetic fields (RF-EMF) emitted by fixed site transmitters. We therefore investigated whether self-reported general well-being in adolescents is affected by RF-EMF exposure from mobile phone base stations (downlink) and broadcast transmitters (TV and radio).
  
  
  
  In a prospective cohort study, 439 study participants aged 12-17 years, completed questionnaires about their self-reported well-being and possible confounding factors at baseline and one year later. Exposure from fixed site transmitters at home and school was calculated by using a geospatial propagation model. Data were analysed using a mixed-logistic cross-sectional model of a combined dataset consisting of baseline and follow-up data and a longitudinal approach where we investigated whether exposure at baseline (cohort analysis) or changes in exposure between baseline and follow-up (change analysis) were related to a new onset of a symptom between baseline and follow-up. All analyses were adjusted for relevant confounders.
  
  
  
  Mean exposure (median; 75(th)) for broadcast transmitters, downlink and total exposure at baseline were 1.9 μW/m(2) (1.0 μW/m(2); 2.8 μW/m(2)), 14.4 μW/m(2) (3.8 μW/m(2); 11.0 μW/m(2)) and 16.3 μW/m(2) (5.8 μW/m(2); 13.4 μW/m(2)), respectively. In cross-sectional analyses no associations were observed between any symptom and RF-EMF exposure from fixed site transmitters. In the cohort and change analyses only a few significant associations were observed including an increased OR for tiredness (2.94, 95%CI: 1.43 to 6.05) for participants in the top 25(th) percentile of total RF-EMF exposure from fixed site transmitters at baseline, in comparison to participants exposed below the median and a decreased OR for exhaustibility (0.50, 95%CI: 0.27 to 0.93) for participants with an exposure increase between baseline and follow-up.
  
  
  
  In this cohort study, using a geospatial propagation model, RF-EMF exposure from fixed site transmitters was not consistently associated with self-reported symptoms in Swiss adolescents. The few observed associations have to be interpreted with caution and might represent chance findings.
authors.affiliation: Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, CH-4002, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Anna
authors.initials: A
authors.lastname: Schoeni
authors.affiliation: Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, CH-4002, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Katharina
authors.initials: K
authors.lastname: Roser
authors.affiliation: ARIAS umwelt.forschung.beratung, Bern, Switzerland.
authors.forename: Alfred
authors.initials: A
authors.lastname: Bürgi
authors.affiliation: Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, CH-4002, Basel, Switzerland. martin.roosli@unibas.ch.|University of Basel, Basel, Switzerland. martin.roosli@unibas.ch.
authors.forename: Martin
authors.initials: M
authors.lastname: Röösli
mesh_terms: D000293:Adolescent; D001288:Attention; D040421:Cell Phone; D002648:Child; D002669:Child Welfare; D004574:Electromagnetic Fields; D004781:Environmental Exposure; D005221:Fatigue / Q000453:epidemiology; D005260:Female; D006261:Headache / Q000453:epidemiology; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D011845:Radio; D011846:Radio Waves; D057566:Self Report; D013557:Switzerland / Q000453:epidemiology; D013690:Television
keywords: Adolescents; Fixed site transmitter; Geospatial propagation model; RF-EMF; Symptoms