Study type: Medical/biological study (experimental study)

Evaluation of HSP70 expression and DNA damage in cells of a human trophoblast cell line exposed to 1.8 GHz amplitude-modulated radiofrequency fields. med./bio.

Published in: Radiat Res 2008; 169 (3): 270-279

Aim of study (acc. to author)

To determine whether radiofrequency electromagnetic fields could induce cellular effects in trophoblast cells.

Background/further details

The effects observed after radiofrequency exposure were compared to those caused by heat (43°C, 1 h) or hydrogen peroxide, which were used as positive controls.
Trophoblast cells have not been used previously in similar experiments. However, their high proliferation and invasion capability, their fine modulation by physiological factors, and their high sensitivity to external stimuli, make these cells an attractive model for investigating possible detrimental effects of radiofrequency electromagnetic fields on cell physiology.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1,817 MHz
Modulation type: pulsed
Exposure duration: continuous for 1 h
  • SAR: 2 W/kg average over time

Exposure 1

Main characteristics
Frequency 1,817 MHz
Type
Waveform
Charakteristic
  • guided field
Exposure duration continuous for 1 h
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Pulse type rectangular
Additional info

TDMA GSM scheme [Pedersen, 1997] with every 26th frame being idle, adding an 8 Hz modulation to the signal

Exposure setup
Exposure source
Chamber The exposure system [Schonborn et al., 2000] located inside an incubator consisted of two 128.5 x 65 x 424 mm³ brass single-mode waveguide resonators (equipped with DC ventilators) that were assigned to exposure or sham condition by the computer-controlled signal unit ensuring blind conditions for the experiment.
Setup Each resonator was equipped with a plastic holder holding six 35-mm Petri dishes arranged in two stacks in the H-field maxima of the standing wave (E-polarization).
Sham exposure A sham exposure was conducted.
Additional info More than 90% of the power coupled into the waveguides was reflected and directed into a 50-Ω terminator via the circulator (included in the amplifier).
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg average over time measured and calculated - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

No evidence was found that a 1 h exposure to GSM 217 Hz induced a HSP70-mediated stress response or primary DNA damage in HTR-8/SVneo cell line.

Study character:

Study funded by

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