Study type: Medical/biological study (experimental study)

Ultra-wideband electromagnetic pulses: lack of effects on heart rate and blood pressure during two-minute exposures of rats med./bio.

By: Jauchem JR, Seaman RL, Lehnert HM, Mathur SP, Ryan KL, Frei MR, Hurt WD
Published in: Bioelectromagnetics 1998; 19 (5): 330-333
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Aim of study (acc. to author)

To report heart rate and mean arterial blood pressure during exposure of anesthetized rats to ultra-wideband pulses.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 0–4 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 min
Exposure 2: 0–4 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 min
Exposure 3: 0–4 GHz
Modulation type: pulsed
Exposure duration: continuous for 2 min

General information

The order of exposures to all four conditions (including sham) was randomised for each animal.

Exposure 1

Main characteristics
Frequency 0–4 GHz
Type
Waveform
Charakteristic
  • guided field
Exposure duration continuous for 2 min
Modulation
Modulation type pulsed
Pulse width 0.97 ns
Rise time 177 ps
Repetition frequency 50 Hz
Additional info

rise time SD ± 21 ps
Exposure setup
Exposure source
Distance between exposed object and exposure source 77 cm
Chamber The tapered outer or ground conductor had a square cross-section of 11.0-71.7 cm on a side in the usable region. The center or septum conductor was 7.8-56.3 cm wide and 2.6 cm thick. A volume of 20 x 20 x 40 cm was available on each side.
Setup The anaesthetised animal was positioned on a Styrofoam block on the bottom wall and centered between the side walls of the GTEM cell with the head towards the source and the thorax 77 cm from the source end.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 104 kV/m peak value measured - ± 2 kV/m
SAR 7.4 mW/kg mean estimated - -
Measurement and calculation details

Electric fields at the sample were monitored using a D-dot probe in the middle of the top wall and 77 cm from the source end. The probe and the animal's thorax were symmetrically located in the same transverse plane. Previous field mappings had shown that the field varied less than 5% over the region occupied by the head and thorax. SAR estimates were determined from the power spectrum and the normalised SAR [Durney et al., 1986] for a spheroidal model of a medium-sized rat for k-polarisation. (When using this method for human exposure, the results were within 0.5 dB of FDTD calculations.)

Exposure 2

Main characteristics
Frequency 0–4 GHz
Type
Waveform
Charakteristic
  • guided field
Exposure duration continuous for 2 min
Modulation
Modulation type pulsed
Pulse width 0.97 ns
Rise time 174 ps
Repetition frequency 500 Hz
Additional info

rise time SD ± 19 ps
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 102 kV/m peak value measured - ± 4 kV/m
SAR 71 mW/kg mean estimated - -

Exposure 3

Main characteristics
Frequency 0–4 GHz
Type
Waveform
Charakteristic
  • guided field
Exposure duration continuous for 2 min
Modulation
Modulation type pulsed
Pulse width 0.99 ns
Rise time 218 ps
Repetition frequency 1,000 Hz
Additional info

rise time SD ± 70 ps
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 87 kV/m peak value measured - ± 4 kV/m
SAR 114 mW/kg mean estimated - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

The results suggest that acute ultra-wideband whole-body exposure under these conditions does not have an immediate detrimental effect on these cardiovascular system variables in anesthetized rats.

Study character:

Study funded by