Various living organisms and human biopsies and cells were tested for any biological action resulting from exposure to pulsed electromagnetic radiation emitted by cathodic tubes from Video Display Terminals (VDTs). Living organisms were maintained under their normal breeding or culture conditions. Control values were obtained before turning on the VDT.
Various effects possibly related to the irradiation have been demonstrated, i.e. a growth delay in algae and Drosophila, abnormal peaks of mortality in Daphnia and Drosophila, and teratological effects in chick embryos. In human testicular biopsies cultured in vitro for 24 hrs in front of a VDT screen, mitotic and meiotic disturbances, accompanied by degenerative aspects of the cells and a significant disorganization of the seminiferous tubules were demonstrated. In humans exposed for 4 and 8 hrs in front of a VDT screen, a decrease of the Na+/K+ ratio and an increase of the urea concentration in urine had been observed, related to a depolarization of the cell membrane.
Biological models also permitted us to observe some characteristics of action between the irradiated cells and the whole organisms. In Drosophila exposed during the embryonic period, a delayed effect has been shown: the radiation effect only appeared at the metamorphosis period, when winged adults flies appeared.
In vitro culture of human tersticular biopsies biological models permitted us to observe some important perturbations at the cellular level.
To accurately precise the original cause of these observed effects, we tested an experimental apparatus, EMF-Bioshield®, developed to prevent the harm from VDT radiation. Effectively, in all cases, it insures an effective protection against the harmful observed biological effects.
Relation between cause and effect has been clearly established by use of biological models. Pulsed electromagnetic radiation emitted by cathodic tubes is responsible for the described perturbations. During our experiments, a 50Hz/220V alternating voltage powered the video display terminals. Measured electric and magnetic fields were 13V/M and 50nT, respectively, indicating a lack in the measures, probably because of an inadapted sensibility of the measuring devices to the cell values. Micro- and nano-technologies should be very useful to create precise and sensible measuring devices at the cellular level.