Study type: Medical/biological study (experimental study)

UMTS base station-like exposure, well-being, and cognitive performance. med./bio.

Published in: Environ Health Perspect 2006; 114 (8): 1270-1275

Aim of study (acc. to author)

To study the influence of an UMTS base station-like signal on well-being and cognitive performance in subjects with and without self-reported sensitivity to radiofrequency electromagnetic fields.

Background/further details

The study was designed as a follow-up study to clarify the reliability of the so-called TNO study (see publication 12820).
117 healthy subjects (33 self-reported sensitive, 84 non-sensitive subjects) participated.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2,140 MHz
Exposure duration: continuous for 45 min
  • electric field strength: 1 V/m unspecified
  • SAR: 6.2 µW/kg average over mass (whole body) (± 1.8 µW/kg and 41% uncertainty)
  • SAR: 150 µW/kg average over mass (10 g) (± 49 µW/kg and 39% uncertainty; peak value for whole body)
  • SAR: 320 µW/kg average over mass (1 g) (± 130 µW/kg and 41% uncertainty; peak value for whole body)
  • SAR: 11 µW/kg average over mass (brain) (± 2.4 µW/kg and 48% uncertainty)
  • SAR: 45 µW/kg average over mass (10 g) (± 13 µW/kg and 45% uncertainty; peak value for brain)
  • SAR: 73 µW/kg average over mass (1 g) (± 16 µW/kg and 44% uncertainty; peak value for brain)
Exposure 2: 2,140 MHz
Exposure duration: continuous for 45 min
  • electric field strength: 10 V/m unspecified
  • SAR: 0.62 mW/kg average over mass (whole body) (± 0.18 mW/kg and 41% uncertainty)
  • SAR: 15 mW/kg average over mass (10 g) (± 4.9 mW/kg and 39% uncertainty; peak value for whole body)
  • SAR: 32 mW/kg average over mass (1 g) (± 13 mW/kg and 41% uncertainty; peak value for whole body)
  • SAR: 1.1 mW/kg average over mass (brain) (± 0.24 mW/kg and 48% uncertainty)
  • SAR: 4.5 mW/kg average over mass (10 g) (± 1.3 mW/kg and 45% uncertainty; peak value for brain)
  • SAR: 7.3 mW/kg average over mass (1 g) (± 1.6 mW/kg and 44% uncertainty; peak value for brain)

Exposure 1

Main characteristics
Frequency 2,140 MHz
Type
Charakteristic
Exposure duration continuous for 45 min
Exposure setup
Exposure source
Distance between exposed object and exposure source 2 m
Chamber Exposure took place in two identical but separate rooms with constant temperature and light conditions. Each room included a one-side-open exposure chamber (2.45 m x 2.3 m x 2.14 m) shielded with RF absorbers on walls and ceiling.
Setup The antenna, tilted 45° from vertical, was located at a height of 1.5 m and a distance of 2 m from the subject. The antenna had a beam width of approximately 75° in horizontal and vertical directions, resulting in a uniform E-field distribution that was verified with a field probe. The electric field was incident with a polarization of 45° from the left back side of the subject, with an angle of 25° with respect to the ear-to-ear vertical plane.
Sham exposure A sham exposure was conducted.
Additional info Each subject attended three experimental sessions at 1-week intervals in a randomized, double-blind crossover design. Pairs of subjects were randomly assigned to one of six possible sequences of the three exposure conditions (sham, 1 V/m and 10 V/m).
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m unspecified measured - -
SAR 6.2 µW/kg average over mass calculated whole body ± 1.8 µW/kg and 41% uncertainty
SAR 150 µW/kg average over mass calculated 10 g ± 49 µW/kg and 39% uncertainty; peak value for whole body
SAR 320 µW/kg average over mass calculated 1 g ± 130 µW/kg and 41% uncertainty; peak value for whole body
SAR 11 µW/kg average over mass calculated brain ± 2.4 µW/kg and 48% uncertainty
SAR 45 µW/kg average over mass calculated 10 g ± 13 µW/kg and 45% uncertainty; peak value for brain
SAR 73 µW/kg average over mass calculated 1 g ± 16 µW/kg and 44% uncertainty; peak value for brain

Exposure 2

Main characteristics
Frequency 2,140 MHz
Type
Charakteristic
Exposure duration continuous for 45 min
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 10 V/m unspecified measured - -
SAR 0.62 mW/kg average over mass calculated whole body ± 0.18 mW/kg and 41% uncertainty
SAR 15 mW/kg average over mass calculated 10 g ± 4.9 mW/kg and 39% uncertainty; peak value for whole body
SAR 32 mW/kg average over mass calculated 1 g ± 13 mW/kg and 41% uncertainty; peak value for whole body
SAR 1.1 mW/kg average over mass calculated brain ± 0.24 mW/kg and 48% uncertainty
SAR 4.5 mW/kg average over mass calculated 10 g ± 1.3 mW/kg and 45% uncertainty; peak value for brain
SAR 7.3 mW/kg average over mass calculated 1 g ± 1.6 mW/kg and 44% uncertainty; peak value for brain

Reference articles

  • Zwamborn APM et al. (2003): Effects of Global Communication system radio-frequency fields on Well Being and Cognitive Functions of human subjects with and without subjective complaints.
  • Kuster N et al. (2000): Recommended minimal requirements and development guidelines for exposure setups of bio-experiments addressing the health risk concern of wireless communications.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • before exposure
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

In both groups, well being and perceived field strength were not associated with actual exposure levels. No consistent condition-induced changes in cognitive performance except for two marginal effects were revealed: At 10 V/m, a slight effect on speed in one of six tasks in the sensitive subjects and an effect on accuracy in another task in non-sensitive subjects was found. Both effects disappeared after multiple endpoint adjustment.
In contrast to the previous study, the authors could not confirm a short-term effect of UMTS base station-like exposure on well being. The reported effects on brain functioning were marginal and may have occurred by chance.
Regarding the implications for public health due to widespread exposure in the living environment, no conclusions about long-term effects of UMTS base station-like electromagnetic fields can be drawn from this study, as only a short-term exposure was applied.

Study character:

Study funded by

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