Study type: Medical/biological study (experimental study)

Measurement of DNA damage and apoptosis in Molt-4 cells after in vitro exposure to radiofrequency radiation. med./bio.

Published in: Radiat Res 2004; 161 (2): 193-200

Aim of study (acc. to author)

To study whether exposure to radiofrequency irradiation can induce DNA damage or apoptosis, Lymphoblastoid cells were exposed to radiofrequency fields at frequencies and modulations of the type used by wireless communication devices.
The study was conducted to determine if the effects of iDEN- and TDMA-modulated radiofrequency signals that were observed previously (publication 2112) could be replicated using the RTL (Radial Transmission Line) exposure system.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 813.56 MHz
Modulation type: pulsed
Exposure duration: continuous for 2, 3 or 21 h
Exposure 2: 836.55 MHz
Modulation type: pulsed
Exposure duration: continuous for 2, 3 or 21 h
Exposure 3: 847.74 MHz
Exposure duration: continuous for 2 or 24 h
Exposure 4: 835.62 MHz
Exposure duration: continuous for 2 or 24 h

General information

Each experiment included a radiation control exposed to 137Cs γ rays at 0.18 Gy/min for a total dose of 1 Gy, and a hyperthermia control exposed to 44°C for 20 min.

Exposure 1

Main characteristics
Frequency 813.56 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2, 3 or 21 h
Modulation
Modulation type pulsed
Additional info

iDEN

Exposure setup
Exposure source
Chamber The exposure facility consisted of a number of Radial Transmission Lines (RTL) located in a temperature controlled room. A description and comprehensive characterisation has been published previously [Moros et al., 1999; Pickard et al., 1999 and 2000].
Setup T-75 flasks containing 40 ml of complete medium were gassed with 5% CO2 and 95% air and capped tightly. Temperature controllers of the RTLs were calibrated to maintain the culture medium in the flasks at 37.0 ± 0.3°C.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 2.4 mW/kg mean measured - -
SAR 24 mW/kg mean measured - -

Exposure 2

Main characteristics
Frequency 836.55 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2, 3 or 21 h
Modulation
Modulation type pulsed
Additional info

TDMA

Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 2.6 mW/kg mean measured - -
SAR 26 mW/kg mean measured - -

Exposure 3

Main characteristics
Frequency 847.74 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 or 24 h
Modulation
Modulation type cf. additional info
Additional info

CDMA

Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 3.2 W/kg mean measured - -

Exposure 4

Main characteristics
Frequency 835.62 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 or 24 h
Modulation
Modulation type cf. additional info
Additional info

FDMA

Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 3.2 W/kg mean measured - -

Reference articles

  • Pickard WF et al. (2000): Experimental and numerical determination of SAR distributions within culture flasks in a dielectric loaded radial transmission line.
  • Pickard WF et al. (1999): Simplified model and measurement of specific absorption rate distribution in a culture flask within a transverse electromagnetic mode exposure system.
  • Moros EG et al. (1999): The radial transmission line as a broad-band shielded exposure system for microwave irradiation of large numbers of culture flasks.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

No statistically significant difference in the level of DNA damage or apoptosis was revealed between sham-treated cells and cells exposed to radiofrequency electromagnetic fields for any frequency, modulation or exposure time.

Study character:

Study funded by

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