Rapid-onset/offset, variably scheduled 60 Hz electric and magnetic field exposure reduces nocturnal serum melatonin concentration in nonhuman primates.

Experiments with rodents indicate that power-frequency electric field (EF) or magnetic field (MF) exposure can suppress the normal nocturnal increase in melatonin concentration in pineal gland and blood. In a separate set of three experiments conducted with nonhuman primates, we did not observe melatonin suppression as a result of 6 weeks of day-time exposure to combined 60 Hz electric and magnetic fields (E/MF) with regularly scheduled "slow" E/MF onsets/offsets. The study described here used a different exposure paradigm in which two baboons were exposed to E/MF with "rapid" E/MF onsets/offsets accompanied by EF transients not found with slowly ramped E/MF onset/offset; profound reductions in nocturnal serum melatonin concentration were observed in this experiment. If replicated in a more extensive experiment, the observation of melatonin suppression only in the presence of E/MF transients would suggest that very specific exposure parameters determine the effects of 60 Hz E/MF on melatonin.

[1]  M. Rollag,et al.  Radioimmunoassay of serum concentrations of melatonin in sheep exposed to different lighting regimens. , 1976, Endocrinology.

[2]  R. Reiter,et al.  Regularly scheduled, day-time, slow-onset 60 Hz electric and magnetic field exposure does not depress serum melatonin concentration in nonhuman primates. , 1995, Bioelectromagnetics.

[3]  R. Reiter,et al.  Static and extremely low frequency electromagnetic field exposure: Reported effects on the circadian production of melatonin , 1993, Journal of cellular biochemistry.

[4]  W R Rogers,et al.  A 60 Hz electric and magnetic field exposure facility for nonhuman primates: design and operational data during experiments. , 1995, Bioelectromagnetics.

[5]  T. Shigemitsu,et al.  Horizontal or vertical 50-Hz, 1-μT magnetic fields have no effect on pineal gland or plasma melatonin concentration of albino rats , 1994, Neuroscience Letters.

[6]  L. E. Anderson,et al.  Evidence for an Effect of ELF Electromagnetic Fields on Human Pineal Gland Function , 1990, Journal of pineal research.

[7]  L. E. Anderson,et al.  60-Hz electric-field effects on pineal melatonin rhythms: time course for onset and recovery. , 1986, Bioelectromagnetics.

[8]  J. H. Lucas,et al.  Chronically indwelling venous cannula and automatic blood sampling system for use with nonhuman primates exposed to 60 Hz electric and magnetic fields. , 1995, Bioelectromagnetics.

[9]  R. Reiter,et al.  Pineal gland “magnetosensitivity” to static magnetic fields is a consequence of induced electric currents (eddy currents) , 1991, Journal of pineal research.

[10]  R. Reiter,et al.  Concurrent determination of enzymatic activities and substrate concentrations in the melatonin synthetic pathway within the same rat pineal gland , 1984, Journal of neuroscience research.

[11]  Masamichi Kato,et al.  Effects of exposure to a circularly polarized 50-Hz magnetic field on plasma and pineal melatonin levels in rats. , 1993, Bioelectromagnetics.