Medical/biological Study (experimental study)

Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50, and 200 Hz. med./biol.

PubMed Entry

Journal web site

Aim of study (according to author)
To study the permeability of blood-brain barrier to endogenous albumin and fibrinogen during exposure to microwaves of 915 MHz as continuous wave and pulse-modulated at the various repetition rates.

Endpoint

• effects on the neurological system: permeability of the blood-brain barrier

Exposure
General category: mobile communication system, GSM, microwaves

Field characteristics	Parameters
field 1: 915 MHz continuous wave (CW) exposure duration: continuous for 2 h	power: 3 W (0.2-3 W) SAR: 0.3 W/kg (brain) SAR: 1.7 W/kg (brain) SAR: 3.3 W/kg (brain) SAR: 5 W/kg (brain)
field 2: 915 MHz pulsed (PW) exposure duration: continuous for 2 h	power: 20 W peak value (2-20 W) SAR: 0.016 W/kg (brain) SAR: 0.04 W/kg (brain) SAR: 0.08 W/kg (brain) SAR: 0.16 W/kg (brain)
field 3: 915 MHz pulsed (PW) exposure duration: continuous for 2 h	power: 20 W peak value (2-20 W) SAR: 0.03 W/kg (brain) SAR: 0.08 W/kg (brain) SAR: 0.15 W/kg (brain) SAR: 0.3 W/kg (brain) SAR: 2.1 W/kg (brain) (at 4 ms pulse width and 20 W in pulse)
field 4: 915 MHz pulsed (PW) exposure duration: continuous for 2 h	power: 20 W peak value (1-20 W) SAR: 0.3 W/kg (brain) SAR: 0.7 W/kg (brain) SAR: 1.7 W/kg (brain) SAR: 3.3 W/kg (brain) SAR: 5 W/kg (brain) (at 6 ms pulse width and 10 W in pulse) SAR: 1 W/kg (brain) (at 0.57 ms pulse width and 20 W in pulse)
field 5: 915 MHz pulsed (PW) exposure duration: continuous for 2 h	power: 10 W peak value (2-10 W) SAR: 0.4 W/kg (brain) SAR: 1 W/kg (brain) SAR: 2.1 W/kg (brain) SAR: 2.9 W/kg (brain) (at 4 ms pulse width and 2 W in pulse)

Exposed system:
animal (species/strain): rat/Fischer 344

Methods
Endpoint/Measurement parameters/Methodology

• effects on the neurological system: permeability of the blood-brain barrier to albumin and fibrinogen

Main outcome of study (according to author)
Exposed animals are at risk concerning opening of the blood-brain barrier and the response is independent of pulse repetition rate. The response is the same for continuous wave as compared with pulse modulation. The response is independent of SAR in the interval 0.016<SAR<2.5 W/kg, but rises for SAR >2.5 W/kg.

(Study character: medical/biological study, experimental study, full/main study)

Study funded by

• Ake Wibergs Foundation, Sweden
• Gunnar, Arvid and Elisabeth Nilssons Research Foundation, Sweden
• University of Lund, Sweden

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