Study type: Medical/biological study (experimental study)

Effects of mobile phone radiation on UV-induced skin tumourigenesis in ornithine decarboxylase transgenic and non-transgenic mice. med./bio.

Published in: Int J Radiat Biol 2003; 79 (4): 221-233

Aim of study (acc. to author)

To evaluate the effects of mobile phone-type radiofrequency radiation on skin tumorigenesis induced by ultraviolet radiation (UV) in transgenic and non-transgenic mice.

Background/further details

Transgenic mice and their non-transgenic littermates were exposed for 52 weeks to UV radiation or a combination of UV radiation and pulsed radiofrequency radiation. The UV dose was 240 Jm-2 delivered three times a week. One group of mice was exposed to Digital Advanced Mobile Phone System (DAMPS)-type radiofrequency radiation (RFR), the other group to Global System for Mobile Communication (GSM)-type radiofrequency radiation (RFR).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 849 MHz
Modulation type: pulsed
Exposure duration: repeated daily exposure for 1.5 h/day, 5 days/week for 52 weeks
  • SAR: 0.5 W/kg average over time (whole body)
  • SAR: 1.5 W/kg peak value (whole body) (during the pulses)
Exposure 2: 902.4 MHz
Modulation type: pulsed
Exposure duration: repeated daily exposure for 1.5 h/day, 5 days/week for 52 weeks
  • SAR: 0.5 W/kg average over time (whole body)
  • SAR: 4 W/kg peak value (whole body) (during the pulses)

General information

The transgenic and non-transgenic mice were randomized separately to four treatment groups: D-AMPS, GSM or sham exposed and cage-control.

Exposure 1

Main characteristics
Frequency 849 MHz
Type
Charakteristic
  • guided field
Exposure duration repeated daily exposure for 1.5 h/day, 5 days/week for 52 weeks
Modulation
Modulation type pulsed
Pulse width 6.67 ms
Repetition frequency 50 Hz
Additional info

Digital Advanced Mobile Phone System (D-AMPS)

Exposure setup
Exposure source
Chamber Three identical rectangular waveguide chambers made of aluminium were used for the D-AMPS, GSM or sham exposures. The exposure system has been described in more detail in the reference article. Computer-controlled mobile phones were used as a signal source and their signals were amplified. Speech was simulated by modulating the carriers with a random sequence of bytes. The output power was absorbed by a coaxial 10 W termination. The sham-exposed group was kept in an unenergised waveguide chamber.
Setup The mice were restrained in small acrylic cylinders (32 mm i.d., length adjustable) preventing them from aligning their longitudinal axis parallel to the electric field. The restrainers were kept by a Styrofoam holder at the centre of the cross-section of the waveguide with the longitudinal axis perpendicular to the electric field and to the direction of propagation. Simultaneous exposure of 25 mice was possible in a chamber. The order of animals in the Styrofoam holder was randomized for each exposure session to ensure identical long-term average exposure.
Additional info All but the cage-control groups were exposed to UV radiation three times a week preceding or after the RF exposure. The animals were exposed to UV radiation using lamps simulating the solar spectrum. The dose of the UV radiation was 1.2 human minimum erythemal dose (MED), i.e. a dose of 240 J/m², calculated according to the CIE wavelength erythemal weighting function (spatial variation within ± 10%, uncertainty of the measured values within ± 10%). The distance of the lamp from the animals was adjusted to reach the intended dose in 35 min. During the UV irradiations, the mice were kept in Macrolon III cages with a shallow wire lid preventing them from piling upon each other.
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.5 W/kg average over time calculated whole body -
SAR 1.5 W/kg peak value calculated whole body during the pulses

Exposure 2

Main characteristics
Frequency 902.4 MHz
Type
Charakteristic
  • guided field
Exposure duration repeated daily exposure for 1.5 h/day, 5 days/week for 52 weeks
Modulation
Modulation type pulsed
Pulse width 0.577 ms
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.5 W/kg average over time calculated whole body -
SAR 4 W/kg peak value calculated whole body during the pulses

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

UV exposure resulted in development of macroscopic skin tumours in 11.5 and 36.8% of non-transgenic and transgenic mice, respectively. The radiofrequency exposures did not give a statistically significant effect on the development of skin tumours in either transgenic or non-transgenic mice, or in combined analysis, but tumour development appeared slightly accelerated especially in non-transgenic mice. No effects of radiofrequency exposures were found on excretion of 6-hydroxymelatonin sulphate into urine or on polyamine levels in dorsal skin.

Study character:

Study funded by

Comments on this article

Related articles