Dimitris J. Panagopoulos

Mechanism for action of electromagnetic fields on cells

A biophysical model for the action of oscillating electric fields on cells, presented by us before [Biochem. Biophys. Res. Commun. 272(3) (2000) 634-640], is extended now to include oscillating magnetic fields as well, extended to include the most active biological conditions, and also to explain why pulsed electromagnetic fields can be more active biologically than continuous ones. According to the present theory, the low frequency fields are the most bioactive ones. The basic mechanism is the forced-vibration of all the free ions on the surface of a cells plasma membrane, caused by an external oscillating field. We have shown that this coherent vibration of electric charge is able to irregularly gate electrosensitive channels on the plasma membrane and thus cause disruption of the cells electrochemical balance and function [Biochem. Biophys. Res. Commun. 272(3) (2000) 634-640]. It seems that this simple idea can be easily extended now and looks very likely to be able to give a realistic basis for the explanation of a wide range of electromagnetic field bioeffects.

Effect of GSM 900-MHz Mobile Phone Radiation on the Reproductive Capacity of Drosophila melanogaster

Pulsed radio frequency, (RF), electromagnetic radiation from common GSM mobile phones, (Global System for Mobile Telecommunications) with a carrier frequency at 900 MHz, “modulated” by human voice, (speaking emission) decreases the reproductive capacity of the insect Drosophila melanogaster by 50%–60%, whereas the corresponding “nonmodulated” field (nonspeaking emission) decreases the reproductive capacity by 15%–20%. The insects were exposed to the near field of the mobile phone antenna for 6 min per day during the first 2–5 days of their adult lives. The GSM field is found to affect both females and males. Our results suggest that this field-radiation decreases the rate of cellular processes during gonad development in insects.

Bioeffects of mobile telephony radiation in relation to its intensity or distance from the antenna

Purpose: To examine the bioactivity of GSM 900 and 1800 (Global System for Mobile Telecommunications) radiations, in relation to the distance from the antenna or to the radiation-field intensities. Materials and methods: Drosophila melanogaster adult insects were exposed to the radiation of a GSM 900/1800 mobile phone antenna at different distances ranging from 0 to 100 cm, and the effect on their reproductive capacity and cell death induction in the gonads by the use of TUNEL (Terminal deoxynucleotide transferase dUTP Nick End Labeling) assay, was studied. Results: These radiations/fields decreased the reproductive capacity by cell death induction, at all the different distances tested. The effect diminished with the distance/decreasing intensities. An increased bioactivity ‘window’ was revealed at distances of 20–30 cm from the mobile phone antenna, (radiation intensity around 10 μW/cm2) where the effect became highest, in relation to smaller or longer distances. The effect diminished considerably for distances longer than 40–50 cm and became not evident for distances longer than 1 m or radiation intensities smaller than 1 μW/cm2. Conclusions: GSM bioactivity is highest for intensities down to less than 10 μW/cm2 and still evident until 1 μW/cm2 exhibiting ‘window’ effects.

Evaluation of Specific Absorption Rate as a Dosimetric Quantity for Electromagnetic Fields Bioeffects

Purpose To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF dosimetry and bioactivity assessment. Methods We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposure and biological effect. Results We find that: a) The energy absorbed by living matter during exposure to environmentally accounted EMFs is normally well below the thermal level. b) All existing methods for SAR estimation, especially those based upon tissue conductivity and internal electric field, have serious deficiencies. c) The only method to estimate SAR without large error is by measuring temperature increases within biological tissue, which normally are negligible for environmental EMF intensities, and thus cannot be measured. Conclusions SAR actually refers to thermal effects, while the vast majority of the recorded biological effects from man-made non-ionizing environmental radiation are non-thermal. Even if SAR could be accurately estimated for a whole tissue, organ, or body, the biological/health effect is determined by tiny amounts of energy/power absorbed by specific biomolecules, which cannot be calculated. Moreover, it depends upon field parameters not taken into account in SAR calculation. Thus, SAR should not be used as the primary dosimetric quantity, but used only as a complementary measure, always reporting the estimating method and the corresponding error. Radiation/field intensity along with additional physical parameters (such as frequency, modulation etc) which can be directly and in any case more accurately measured on the surface of biological tissues, should constitute the primary measure for EMF exposures, in spite of similar uncertainty to predict the biological effect due to non-linearity.

Comparison of Bioactivity Between GSM 900 MHz and DCS 1800 MHz Mobile Telephony Radiation

An increasing number of studies find that pulsed Radio Frequency (RF), electromagnetic radiation of both systems of digital mobile telephony, established and commonly used in Europe during the last years, GSM 900 MHz (Global System for Mobile telecommunications) and DCS 1800 MHz (Digital Cellular System), exert intense biological action on different organisms and cells (Hardell et al., 19; Hyland, 23; Kundi, 26; Panagopoulos et al., 4445). The two types of cellular telephony radiation use different carrier frequencies and give different frequency spectra, but they usually also differ in intensity, as GSM 900 MHz antennas operate at about double the power output than the corresponding DCS 1800 MHz ones. In our present experiments, we used a model biological system, the reproductive capacity of Drosophila melanogaster, to compare the biological activity between the two systems of cellular mobile telephony radiation. Both types of radiation were found to decrease significantly and non thermally the insects reproductive capacity, but GSM 900 MHz seems to be even more bioactive than DCS 1800 MHz. The difference seems to be dependent mostly on field intensity and less on carrier frequency.

Biological Effects of EMFs

People have always considered the exposure to non-ionising radiation with scepticism. The prospect that exposure to electromagnetic fields (EMF) can have a deleterious effect or any effect on cellular behaviour has been debated in scientific and journalistic circles for some years. The drive to determine whether EMFs were involved in cellular behavioural changes is critical since environmental proximity to high voltage power lines and electric stations or the routine use of household appliances and cellular phones is increasing exponentially. Support for a deleterious effect gained impetus with the report that children whose homes were close to power lines had a higher frequency of leukemia. If cell signalling is influenced by EMF exposure, it provides further impetus to determine whether EMF exposure can cause or alter the propensity to cancer or have other deleterious effects in cells. Numerous laboratory studies both in vitro and in vivo have provided evidence that exposure to EMF induces a wide range of responses in biological systems.

The identification of an intensity ‘window’ on the bioeffects of mobile telephony radiation

Purpose: The increased bioactivity ‘windows’ of GSM 900 and 1800 MHz radiations, (Global System for Mobile telecommunications) revealed recently by us and published in this issue, manifesting themselves as a maximum decrease in the reproductive capacity of the insect Drosophila melanogaster, were examined to discover whether they depend on the intensity of radiation-fields. Methods: In each experiment, one group of insects were exposed to the GSM 900 or 1800 radiation at 30 or 20 cm distances, respectively, from the antenna of a mobile phone, where the bioactivity ‘window’ appears for each type of radiation and another group was exposed at 8 or 5 cm, respectively, behind a metal grid, shielding both microwave radiation and the extremely low frequency (ELF) electric and magnetic fields for both types of radiation in a way that radiation and field intensities were roughly equal between the two groups. Then the effect on reproductive capacity was compared between groups for each type of radiation. Results: The decrease in the reproductive capacity did not differ significantly between the two groups. Conclusions: The bioactivity window seems to be due to the intensity of radiation-field (10 μW/cm2, 0.6–0.7 V/m) at 30 or 20 cm from the GSM 900 or 1800 mobile phone antenna, respectively.

Polarization: A Key Difference between Man-made and Natural Electromagnetic Fields, in regard to Biological Activity

In the present study we analyze the role of polarization in the biological activity of Electromagnetic Fields (EMFs)/Electromagnetic Radiation (EMR). All types of man-made EMFs/EMR - in contrast to natural EMFs/EMR - are polarized. Polarized EMFs/EMR can have increased biological activity, due to: 1) Ability to produce constructive interference effects and amplify their intensities at many locations. 2) Ability to force all charged/polar molecules and especially free ions within and around all living cells to oscillate on parallel planes and in phase with the applied polarized field. Such ionic forced-oscillations exert additive electrostatic forces on the sensors of cell membrane electro-sensitive ion channels, resulting in their irregular gating and consequent disruption of the cell’s electrochemical balance. These features render man-made EMFs/EMR more bioactive than natural non-ionizing EMFs/EMR. This explains the increasing number of biological effects discovered during the past few decades to be induced by man-made EMFs, in contrast to natural EMFs in the terrestrial environment which have always been present throughout evolution, although human exposure to the latter ones is normally of significantly higher intensities/energy and longer durations. Thus, polarization seems to be a trigger that significantly increases the probability for the initiation of biological/health effects.

Real versus Simulated Mobile Phone Exposures in Experimental Studies.

We examined whether exposures to mobile phone radiation in biological/clinical experiments should be performed with real-life Electromagnetic Fields (EMFs) emitted by commercially available mobile phone handsets, instead of simulated EMFs emitted by generators or test phones. Real mobile phone emissions are constantly and unpredictably varying and thus are very different from simulated emissions which employ fixed parameters and no variability. This variability is an important parameter that makes real emissions more bioactive. Living organisms seem to have decreased defense against environmental stressors of high variability. While experimental studies employing simulated EMF-emissions present a strong inconsistency among their results with less than 50% of them reporting effects, studies employing real mobile phone exposures demonstrate an almost 100% consistency in showing adverse effects. This consistency is in agreement with studies showing association with brain tumors, symptoms of unwellness, and declines in animal populations. Average dosimetry in studies with real emissions can be reliable with increased number of field measurements, and variation in experimental outcomes due to exposure variability becomes less significant with increased number of experimental replications. We conclude that, in order for experimental findings to reflect reality, it is crucially important that exposures be performed by commercially available mobile phone handsets.

Pulsed electric field increases reproduction

Abstract Purpose To study the effect of pulsed electric field – applied in corona discharge photography – on Drosophila melanogaster reproduction, possible induction of DNA fragmentation, and morphological alterations in the gonads. Materials and methods Animals were exposed to different field intensities (100, 200, 300, and 400 kV/m) during the first 2–5 days of their adult lives, and the effect on reproductive capacity was assessed. DNA fragmentation during early- and mid-oogenesis was investigated by application of the TUNEL (Terminal deoxynucleotide transferase dUTP Nick End Labeling) assay. Sections of follicles after fixation and embedding in resins were observed for possible morphological/developmental abnormalities. Results The field increased reproduction by up to 30% by increasing reproductive capacity in both sexes. The effect increased with increasing field intensities. The rate of increase diminished at the strongest intensities. Slight induction of DNA fragmentation was observed exclusively in the nurse (predominantly) and follicle cells, and exclusively at the two most sensitive developmental stages, i.e., germarium and predominantly stage 7–8. Sections of follicles from exposed females at stages of early and mid-oogennesis other than germarium and stages 7–8 did not reveal abnormalities. Conclusions (1) The specific type of electric field may represent a mild stress factor, inducing DNA fragmentation and cell death in a small percentage of gametes, triggering the reaction of the animal’s reproductive system to increase the rate of gametogenesis in order to compensate the loss of a small number of gametes. (2) The nurse cells are the most sensitive from all three types of egg chamber cells. (3) The mid-oogenesis checkpoint (stage 7–8) is more sensitive to this field than the early oogenesis one (germarium) in contrast to microwave exposure. (4) Possible therapeutic applications, or applications in increasing fertility, should be investigated.