authors studied the effect of a RF electromagnetic field on the nervous
system control of blood pressure. Ten young adults were sham-exposed
to a phone model fixed to the right side of the head for 35 minutes,
and then exposed to EMF at 900 MHz, pulse frequency 217 Hz, simulating
a GSM phone system. At the end of each period of sham exposure or
exposure, blood pressure was measured in the resting state, during
standing for 60 seconds, and during a Valsalva manoeuvre, which causes
changes in the lung pressures and in heart rate and blood pressure.
Resting blood pressure was increased by 5-10 mm Hg after EMF exposure.
The authors speculate that these changes were due to an increase in
the sympathetic component of the autonomic
nervous system. There were no other significant differences between
the exposure and sham periods.