Michael A Persinger and Linda S. St-Pierre
Female rats that had received only four oral administrations of Dimethylbenz(a) anthracene (DMBA) were exposed for one year every night for about 6 min every hour between midnight and 08 hr to various intensities of 7 Hz, amplitude modulated magnetic fields generated through Helmholtz coils. The rats exposed to intensities between 400 and 500 nT did not develop any overt tumors even though they received DMBA. On the other hand rats exposed to the intensities between 30 and 60 nT developed a variety of different, qualitatively unusual tumors that were located within pancreatic, salivatory, and nasal tissues. Their histological features are presented. These results should be considered preliminary but suggest that protracted exposures to particularly patterned and intensity magnetic fields during the nocturnal cycle may suppress the chemical reactions that contribute to the nuclear changes in the cell or the intercellular cohesive networks that ultimately trigger these massive proliferations of tissue.
