Effect of electromagnetic irradiation produced by 3G mobile phone on male rat reproductive system in a simulated scenario.

Reports of declining male fertility have renewed interest in assessing the role of electromagnetic fields (EMFs). Testicular function is particularly susceptible to the radiation emitted by EMFs. Significant decrease in sperm count, increase in the lipid peroxidation damage in sperm cells, reduction in seminiferous tubules and testicular weight and DNA damage were observed following exposure to EMF in male albino rats. The results suggest that mobile phone exposure adversely affects male fertility.

Specific absorption rate variation in a brain phantom due to exposure by a 3G mobile phone: Problems in dosimetry.

A specific absorption rate (SAR) measurements system has been developed for compliance testing of personal mobile phone in a brain phantom material contained in a Perspex box. The volume of the box has been chosen corresponding to the volume of a small rat and illuminated by a 3G mobile phone frequency (1718.5 MHz), and the emitted radiation directed toward brain phantom .The induced fields in the phantom material are measured. Set up to lift the plane carrying the mobile phone is run by a pulley whose motion is controlled by a stepper motor. The platform is made to move at a pre-determined rate of 2o per min limited up to 20o. The measured data for induced fields in various locations are used to compute corresponding SAR values and inter comparison obtained. These data are also compared with those when the mobile phone is placed horizontally with respect to the position of the animal. The SAR data is also experimentally obtained by measuring a rise in temperature due to this mobile exposures and data compared with those obtained in the previous set. To seek a comparison with the safety criteria same set of measurements are performed in 10 g phantom material contained in a cubical box. These results are higher than those obtained with the knowledge of induced field measurements. It is concluded that SAR values are sensitive to the angular position of the moving platform and are well below the safety criteria prescribed for human exposure. The data are suggestive of having a fresh look to understand the mode of electromagnetic field -bio interaction.

Biomarkers of induced electromagnetic field and cancer.

The present article delineates the epidemiological and experimental studies of electromagnetic field which affects various tissues of human body. These affects lead to cell proliferation, which may lead to cancer formation. Certain biomarkers have been identified which are one way or the other responsible for tumor promotion or co-promotion. These are (i) melatonin, a hormone secreted by pineal gland, (ii) Ca2+, which is essential in the regulation of the resting membrane potential and in the sequence of events in synaptic excitation and neurotransmitter, release are affected by electromagnetic field, (iii) ornithine decarboxylase (ODC), a rate-limiting enzyme in the biosynthesis of polyamines, considered as a useful biological marker; over expression of ODC can cause cell transformation and enhancement of tumor promotion. (iv) protein kinase is an enzyme, which transfers phosphate groups from ATP to hydroxyl groups in the amino acid chains of acceptor proteins, and (v) Na+-K+ ATPase, which transports sodium and potassium ions across the membrane has a critical role in living cells. The various possible mechanisms depending upon non equilibrium thermodynamics, co-operativism, stochastic and resonance are discussed as possible models of signal transduction in cytosol, thereby controlling the transcription phenomena. Finally a mechanism comprising the extremely low frequency and radio frequency (RF)/microwave (MW) modulated field is compared.

Effect of amplitude modulated RF radiation on calcium ion efflux and ODC activity in chronically exposed rat brain.

The effect of exposing rats to amplitude modulated radiofrequency radiation (112 MHz modulated to 16 Hz) during development and growth has been examined. Wistar rats (35 days old) when exposed at above frequency at the power level 1.0 mW/cm2 (SAR, 0.75 W/kg) for 35 days showed enhanced ornithine decarboxylase activity and Ca2+ efflux in brain indicating potential health hazards due to exposure.

Issues in electromagnetic field-biointeractions.

Low level electromagnetic fields have been found to produce a variety of biological effects, though the mechanism of such interaction is still not completely understood. Cell membrane of the brain is a critical structure perceiving the action of microwaves, which has received greater attention in the recent past. The interactions of EMF with the living cells are considered as stochastic resonance, cooperative effects, non-equilibrium thermodynamic process and non-linear interactions. The living cells derive the energy from noise and pumps it into the modes of excitation at the driving frequency of an electromagnetic wave which give sufficient amplification of the signal and increase the signal to noise ratio. The non-linear mechanism plays their main role in the process of transmembrane coupling of the signal to the cytoplasm. The criteria for safe exposure limits of electromagnetic field to humans is also discussed.

Exposure effects of static magnetic field on some physiological parameters of developing rats.

Effect of long term exposure of static magnetic field on developing rats is investigated. The animals of either sex were subjected to a field of 1 kg for 120 days after attaining 28 days of their ages. The parameters included for observations were electrocardiogram, motor activity, and organ weights. The electrocardiogram of the experimental animals shows a higher amplitude of R and T waves, lengthening of QT interval and a slowing down of heart rate. The survival time of the two categories of animals was not significantly different. The weights of brain, skull and ovaries found to be significantly less in experimental group, while the motor activity of the corresponding group registered an increase. It is concluded that these are the stressor effects caused due to long duration of exposure to the magnetic field.

Poly ADP ribosylation as a possible mechanism of microwave--biointeraction.

Electromagnetic fields (EMFs) affect the metabolism of the body including the nervous, endocrine, cardiovascular, hematological as well as the reproductive system. EMFs are environmental pollutants, thus posing a health hazard which can cause steric changes in the molecule located at the cell surface. Microwaves are known to cause chromosomal abberations and act as tumor promoters. The process involves a stream of signals from cell membrane to nucleus and other organelles. The present investigations aim to understand the mechanism of biological effects of microwaves (2.45 GHz). The effect was studied on poly ADP-ribosylation, which is a post translational modification of chromatin protein catalysed by the enzyme poly ADPR polymerase using NAD+ as the substrate. Poly ADP-ribosylation has been shown to be involved in several aspects of chromatin structure and function. Twenty-three days old rats weighing 42-48 gms were exposed at a microwave dose level of 1.0 mW/cm2. After exposure for sixty days the animals were sacrificed and an estimation of poly ADPR polymerase activity was undertaken in different organs of these animals. There was an increase of 20% in its activity in liver, 35% in testis, whereas brain showed a 53% decrease in diencephalon and 20% decrease in the cortex in the exposed animals as compared to their respective controls. There was no change in enzyme activity in spleen and kidney. This was accompanied by concomitant changes in NAD+ levels. The above results may be cited as important events in carcinogenesis and tumor promotion related to microwave exposure and the signal transduction mechanism involved. The goal is to shed light on complex ecogenetic interactions leading to cancer modulation of gene expression by epigenetic mechanism.

Ultrasound nonlinearity parameter (B/A) in biological tissues.

The ultrasonic nonlinearity parameter B/A is determined using the finite amplitude distortion method. The generation of second harmonic as a result of propagation of ultrasonic wave through the media, were measured by the receiving transducer (4.0 MHz) placed coaxial with the same sized cylindrical transmitting transducer (2.0 MHz). The second harmonic component of the wave, were analysed and recorded. The values of B/A of liver, kidney, spleen and heart tissues turns out to be 7.48, 6.75, 9.89 and 6.45 respectively.