Study type: Medical/biological study (experimental study)

Effects of 1.8 GHz radiofrequency field on DNA damage and expression of heat shock protein 70 in human lens epithelial cells. med./bio.

Published in: Mutation Research - Fundamental and Molecular Mechanism of Mutagenesis 2006; 602 (1-2): 135-142

Aim of study (acc. to author)

To investigate the in vitro effects of 1.8 GHz radiofrequency field (GSM) on human eye lens cells.

Background/further details

As the specific absorption rate of 4 W/kg is the accepted dose threshold for thermal and non-thermal effects, eye lens cells were exposed to three different specific absorption rates lower than this threshold (1, 2 and 3 W/kg) to avoid thermal effects.
DNA damage and Hsp expression were explored 0, 0.5, 1, 2, and 4 hours after exposure. Cell proliferation was determined on days 0, 1 and 4 after exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1.8 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 h

Exposure 1

Main characteristics
Frequency 1.8 GHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 h
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

There are contradictory statements in the article, whether the signal was 217 Hz GSM or CW.

Exposure setup
Exposure source
Chamber Two rectangular anechoic single-mode resonator cavities with fans, one for RF and one for sham exposure, were placed in an incubator at 37 °C, 5% CO2, saturated vapour.
Setup Six 35-mm Petri dishes containing 2 ml of medium were placed on dish holders inside each waveguide exactly in the H-field maximum of the standing wave.
Sham exposure A sham exposure was conducted.
Additional info Negative and positive (40 °C for 0.5 h) incubator controls were also used.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1 W/kg - - - -
SAR 2 W/kg - - - -
SAR 3 W/kg - - - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The results showed no significant difference of DNA damage between the exposed and sham-exposed groups induced by specific absorption rates of 1 and 2 W/kg at any incubation time point. The DNA damage caused by 3 W/kg irradiation was significantly increased at the times of 0 and 30 minutes after exposure, a phenomenon that could not be seen at the time points of 1, 2, and 4 hours.
Hsp70 mRNA expression as well as Hsp70 protein expression was found in all exposure groups. Exposure at specific absorption rates of 2 and 3 W/kg for 2 hours exhibited significantly increased Hsp70 protein expression, while no change in Hsp70 mRNA expression could be found in any of the groups.
No difference of the cell proliferation rate between the sham-exposed and exposed cells was found.

Study character:

Study funded by

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