Chronic exposure of primates to 60-Hz electric and magnetic fields: III. Neurophysiologic effects.
The neurophysiologic effects of combined 60-Hz electric (E) and magnetic (B) fields, of magnitudes comparable to those produced by high-voltage powerlines, were investigated in 10 monkeys (Macaca nemestrina). Six animals (experimental group) were each exposed to three different levels of E and B fields: 3 kV/m and 0.1 G, 10 kV/m and 0.3 G, and 30 kV/m and 0.9 G. Field exposures were preceded and followed by sham exposures, during which factors of field generation were present (e.g., heat, vibration, noise, etc.) without E and B fields. Each of the five segments (i.e., the three exposure segments and the initial and final sham exposure segments) lasted 3 weeks. Animals were exposed for 18 h/day (fields on at 1600 h, off at 1000 h). Four other animals (external control group) were given sham exposure for the entire 15-week period. Auditory, visual, and somatosensory evoked potentials were recorded twice a week, during the daily 6-h field-off period. E- and B-field exposure had no effect on the early or mid-latency evoked potential components, suggesting that exposure at these levels has no effect on peripheral or central sensory afferent pathways. However, there was a statistically significant decrease in the amplitudes of late components of the somatosensory evoked potential during the 10kV/m and 0.3 G, and 30 kV/m and 0.9 G exposure levels. This result is possibly related to the opiate antagonist effect of electromagnetic field exposure reported by others.
Dowman
R
R
Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany, New York.
Wolpaw
J R
JR
Seegal
R F
RF
Satya-Murti
S
S
D000818:Animals; D004574:Electromagnetic Fields / Q000009:adverse effects*; D055590:Electromagnetic Phenomena / Q000009:adverse effects*; D004781:Environmental Exposure; D005071:Evoked Potentials / Q000528:radiation effects*; D005072:Evoked Potentials, Auditory / Q000528:radiation effects; D005073:Evoked Potentials, Somatosensory / Q000528:radiation effects; D005074:Evoked Potentials, Visual / Q000528:radiation effects; D008254:Macaca nemestrina; D008297:Male