Effects of Extremely Low Frequency Electromagnetic Fields on Physarum polycephalum

Microplasmodia from the slime mold Physarum polycephalum have been continuously exposed to weak electromagnetic fields at 45, 60, and 75 Hz. To date, microplasmodia have been exposed to fields of 75 Hz, 2.0 G, 0.7 V/m for more than 700 days. Two other sets of cultures have been exposed to 45 and 60 Hz fields (2.0 G, 0.7 V/m) for 180 and 400 days, respectively. The time between successive mitotic divisions in cultures exposed to fields varied from 0.5 to 2 hr longer than their respective controls. The mitotic delay is reproducible, and the onset appears to be frequency dependent with approximately 14, 90, and 120 days exposure to 45, 60, and 75 Hz electromagnetic radiation required before a significant effect is observed. Removal of affected cultures from the electromagnetic field (75 Hz, 2.0 G, 0.7 V/m) results in the disappearance of the mitotic delay in approximately 40 days. In addition to the mitotic delay, a retardation in reversible protoplasmic streaming was observed at all frequencies.