Study type: Medical/biological study (experimental study)

Cytogenetic studies in human blood lymphocytes exposed in vitro to 2.45 GHz or 8.2 GHz radiofrequency radiation. med./bio.

Published in: Radiat Res 2006; 166 (3): 532-538

Aim of study (acc. to author)

To determine whether radiofrequency causes cytogenetic damage in human blood lymphocytes exposed in vitro.

Background/further details

Aliquots of the same blood samples from three male donors were used as positive controls (PHA-stimuated or to 1.5 Gy gamma radiation exposed cells).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 h
Exposure 2: 8.2 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 h

General information

For positive control, samples were exposed to 1.5 Gy gamma radiation (137Cs source) at a dose rate of 1.008 Gy/min.

Exposure 1

Main characteristics
Frequency 2.45 GHz
Type
Exposure duration continuous for 2 h
Modulation
Modulation type pulsed
Pulse width 10 µs
Duty cycle 10 %
Repetition frequency 10 kHz
Exposure setup
Exposure source
Distance between exposed object and exposure source 1.75 m
Exposure room The temperature in the anechoic room (18 x 9 x 9 ft) was maintained at 37 ± 1°C. The temperature in the incubator box was maintained at 36.9 ± 0.1°C by a flow of warm air through tubing immersed in a water bath and was monitored continuously using a Vitek probe.
Setup T-25 tissue culture flasks containing 6 ml of whole blood were placed in an incubator box at a distance of 1.75 m from the opening of the antenna.
Sham exposure A sham exposure was conducted.
Additional info The cells were allowed to settle at the bottom of the culture flasks for 2 h before exposure.
Parameters
Measurand Value Type Method Mass Remarks
power density 5 mW/cm² mean measured - -
SAR 2.135 W/kg mean calculated - ± 0.005 W/kg

Exposure 2

Main characteristics
Frequency 8.2 GHz
Type
Exposure duration continuous for 2 h
Modulation
Modulation type pulsed
Pulse width 8 ns
Duty cycle 0.04 %
Repetition frequency 50 kHz
Exposure setup
Exposure source
Distance between exposed object and exposure source 1.46 m
Exposure room The anechoic room was 20 x 14 x 10 ft. The temperature in the incubator box was maintained at 37.4 ± 0.4°C by a flow of warm water from a compartment underneath and was monitored continuously using a Vitek probe.
Setup T-25 tissue culture flasks containing 6 ml of diluted blood were placed in an incubator box at a distance of 1.46 m from the opening of the antenna.
Sham exposure A sham exposure was conducted.
Additional info In a second group, PHA (1%) was added to the diluted blood, and cultures were incubated at 37 ± 1°C for 24 h to stimulate the lymphocytes before exposure.
Parameters
Measurand Value Type Method Mass Remarks
power density 10 mW/cm² mean measured - -
SAR 20.71 W/kg mean calculated - ± 0.08 W/kg

Reference articles

  • Natarajan M et al. (2002): NF-kappaB DNA-binding activity after high peak power pulsed microwave (8.2 GHz) exposure of normal human monocytes.
  • Vijayalaxmi et al. (1997): Proliferation and cytogenetic studies in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The levels of cytogenetic damage in radiofrequency irradiation exposed and sham-exposed lymphocytes were not significantly different. Also in the response of unstimulated lymphocytes and lymphocytes stimulated with PHA were no signficant differences when exposed to 8.2 GHz radiofrequency irradiation. In contrast, the positive control cells that had been subjected to 1.5 Gy gamma radiation exhibited significantly more cytogenetic damage than radiofrequency irradiation- and sham-exposed lymphocytes.

Study character:

Study funded by

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