Study type: Medical/biological study (experimental study)

Electromagnetic noise inhibits radiofrequency radiation-induced DNA damage and reactive oxygen species increase in human lens epithelial cells. med./bio.

Published in: Mol Vis 2008; 14: 964-969

Aim of study (acc. to author)

To study the influence of the 1.8 GHz radiofrequency fields (GSM) on DNA damage and intracellular reactive oxygen species formation in human eye lens epithelial cells and whether the effects induced by radiofrequency could be blocked by superposing of electromagnetic noise (2 µT).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1.8 GHz
Modulation type: pulsed
Exposure duration: intermittent, 5 min on/10 min off, for 2 h
Exposure 2: 30–90 Hz
Exposure duration: intermittent, 5 min on/10 min off, for 2 h

General information

The cells were subjected to one of four exposure conditions: sham, RF radiation (4 levels), noise MF, and RF radiation superposed with noise MF.

Exposure 1

Main characteristics
Frequency 1.8 GHz
Type
Charakteristic
  • guided field
Exposure duration intermittent, 5 min on/10 min off, for 2 h
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Pulse type rectangular
Additional info

GSM signal

Exposure setup
Exposure source
Chamber Two waveguides, one for RF and one for sham exposure, were placed inside a conventional incubator at 37 °C with 5% CO2 and 95% air.
Setup Six 35-mm Petri dishes with cells in a total volume of 2 ml were placed in a dish holder inside the waveguide holding them exactly in the H-field maximum of the standing wave and were exposed simultaneously in E polarization.
Sham exposure A sham exposure was conducted.
Additional info The system enabled the exposure of a monolayer of cells with less than 30% non-uniformity of the SAR.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1 W/kg mean - - -
SAR 2 W/kg mean - - -
SAR 3 W/kg mean - - -
SAR 4 W/kg mean - - -

Exposure 2

Main characteristics
Frequency 30–90 Hz
Type
Exposure duration intermittent, 5 min on/10 min off, for 2 h
Additional info white noise signal
Exposure setup
Exposure source
Chamber To generate a noise MF, both sides of the waveguides were wrapped with two rectangular Helmholtz coils having a center distance of 24 cm.
Additional info The direction of the coils was the same as the circular wires in the RF waveguides, and the direction of the noise MF was consistent with the magnetic field of the RF radiation.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 2 µT - - - "Amplitude"

Reference articles

  • Yao K et al. (2008): Effect of superposed electromagnetic noise on DNA damage of lens epithelial cells induced by microwave radiation. (RETRACTED by publisher)

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

After exposure to 1.8 GHz radiofrequency electromagnetic field for 2 h, the cells exhibited significant intracellular reactive oxygen species production increase in the 2, 3, and 4 W/kg groups. Radiofrequency exposure at the SAR of 3 W/kg and 4 W/kg could induce significant DNA damage in the alkaline comet assay, while no statistical difference in double strand breaks was found between exposure (3 and 4 W/kg) and sham exposure groups.
When radiofrequency was superposed with 2 µT electromagnetic noise could block radiofrequency-induced reactive oxygen species increase and DNA damage.
In conclusion, DNA damage induced by 1.8 GHz radiofrequency field may be associated with the increased reactive oxygen species production. Electromagnetic noise could block this radiofrequency-induced intracellular reactive oxygen species formation and DNA damage.

Study character:

Study funded by

Related articles