Medical/biological study (observational study)

Possible Effects of Electromagnetic Fields from Phone Masts on a Population of White Stork (Ciconia ciconia)

Published in: Electromagn Biol Med 2005; 24 (2): 109-119

Aim of study (acc. to author)

To monitor of a white stork population in Valladolid (Spain) in the vicinity of cellular phone base stations with the objective of detecting possible effects.
Background/further details: 60 nests were monitored. Nests were separated in two categories: Nests located within 200 m of one or several antennae and nests located furhter than 300 m.



Exposure Parameters
Exposure 1: 900–1,800 MHz
Modulation type: pulsed
Exposure duration: continuous during all phases of breeding
Exposure 1
Main characteristics
Frequency 900–1,800 MHz
Exposure duration continuous during all phases of breeding
Modulation type pulsed
Exposure setup
Exposure source
Setup Nests were either located within 200 m from one or several BTS antennae or located more than 300 m from any BTS. They were situated on masts and on the roofs of buildings at a height of 15-30 m.
Measurand Value Type Method Mass Remarks
electric field strength 2.36 V/m mean measured - nests within 200 m
electric field strength 0.53 V/m mean measured - nests farther than 300 m
Measurement and calculation details
Electric field was measured using a "Nuova Elettronica" device with 10% sensitivity, from a unidirectional antenna. The measurements were made in the vicinity of the nests under similar conditions with the antenna directed toward the BTS antenna in line of sight.
Exposed system:
  • animal
  • White stork (Ciconia ciconia)
  • whole body

Methods Endpoint/measurement parameters/methodology

  • effects on the reproductive system: breeding success (total productivity/number of youngs by each couple, including nests with 0 chicks; partial productivity/number of youngs by each couple, excluding nests with 0 chicks) (telescope observation)
Investigated material:
Investigated organ system:
Time of investigation:
  • during exposure

Main outcome of study (acc. to author)

The total productivity in the nests located within 200 meters of antennae, was 0.86 ± 0.16 and the partial productivity was 1.44 ± 0.16. For those located further than 300 m, the total productivity was practically doubled, with an average of 1.6 ± 0.14. Partial productivity was 1.65 ± 0.13.
Twelve nests (40%) located within 200 m of antennae never had chicks, while only one located further than 300 m had no chicks.
Study character:

Study funded by

  • not stated/no funding

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