Tuesday, January 15, 2013


Reference Literature Survey - Part 2

I have been invited to deliver a lecture on Electro Magnetic Interference and Electro Magnetic Compatibility abbreviated as EMI / EMC. I have deciced to speak on the topic of Electromagnetic Pollution (or Electropollution).

This gives me a chance to brush up my rusty knowledge and let me begin by going through a few book reviews I had written earlier when I used to regularly teach this subject at the Post Graduate Level and conduct specialized training on EMI / EMC too during my faculty days at DIAT Deemed University located in the hills of Girinagar near Pune

So, Dear Reader, in case you are interested in this topic of Electromagnetic Pollution and its manifestations, do read on:

This is Part 2 in this series. 
The link to Part 1 is given below:
Part 1 - Book ReviewBiological Effects of Microwaves by S Baranski and P Czerski


Here is an edited and abridged version of a book review written by one of my bright students Shashank Kekre a few years ago:

Details of the Book


Book Review

This book is a collection of scientific and technical research papers of the IEEE, collected by efforts of Committee of Man and Radiation (COMAR) and is very useful for the study of Biological Effects of Electromagnetic Radiation. 

The book helps to understand the bottom-line results and also some of the reports which have greatly influenced this field of research and its practical relevance. 

The papers are presented in seven separate parts with associated references. 

The book also focuses about measures like Specific Absorption Rates (SAR), exposure on people, susceptibility standards for electronic devices to be implanted into people and beneficial medical applications of Electromagnetic Radiations. 

Some research papers also show the tests and experiments done on different animals (mammals) to demonstrate the hazards effects, and uses of electromagnetic radiations.

The book comprises of seven parts. 

Every part is compiled by various editors to cover the broad aspects of the topic by collecting different technical papers. 

A brief review on various topics is covered on subsequent paragraphs.

The first part deals with relationship between the properties of the exposure fields and the absorbed energy (rate of energy absorption) or fields in the exposed tissues. HP Schwan and GM Piersol brought out with their review to evaluate the biophysical mechanisms by which electromagnetic radiation is absorbed in tissue, and its medical applications. 

The next paper reveals the effects of temperature distribution over tissues when exposed to different kinds of radiation sources. EL Hunt, RD Phillips, DM Fleming, RD Castro have demonstrated a dosimetry system which measures the heat generated by “carcass” (dead and burnt body of an animal) thereby measuring electromagnetic wave exposure. 

The next paper states the heating patterns of cranial (skull) structure in microwave pattern. There are several problems associated with the electromagnetic wave propagation effects in living organisms. The low frequencies also now known for harmful effects due to long time exposure such as behavioral changes, burns, cataracts, etc in animal tissues. 

Further going ahead, the next paper by Habib Massoudi, Carl H Durney, and Curtis C Johnson shows the calculations of the power absorbed by an ellipsoidal model of man are given for six different orientations of the ellipsoid with respect to the incident plane wave field vectors. The results show that the induced fields and the absorbed power in the ellipsoid are strong functions of frequency, size, and orientation with respect to the incident field vectors. However, the syndicates of this paper have determined a formula that is an approximate numerical method of curve fitting to find the average specific absorption rate (SAR) over a broad frequency range. Now that we know that mammals are largely affected by microwaves, there was a requirement of measurement of these exposures, the paper by Ronald R Bowman suggests a thermistor probe and a very high resistance plastic leads to measure the RF frequency exposure. 

The last paper of this part by Om P Gandhi states electromagnetic dose for different parts of man and animals at various incident frequencies with the change in orientations of body. A typical sketch of human body is shown to illustrate the distribution of power deposition for an average specific absorption rate.

The second part brings about the various approaches on the biophysical interactions of the RF fields. 

The first paper by W Ross Adey illustrates that the nervous exhibits a rhythmic electrical activities, a set of electrical signals when we do different daily activity, even in different moods. The Electroencephalogram (EEG) measures such kind of electrical signals. Thus, brain cells also sense field potentials, which bring changes in the behavior. 

The next paper by SA Moskalenko, MF Miglei, PI Khaoshi, EP Pokatilov and ES Kiselyova states that a biological system is considered as a macroscopic model consisting of separate units which oscillate with different frequencies due to the interaction among themselves and form a set of electric dipole oscillators. There is an individual finite group of modes among these units they are called active phonons. Now if the energy is supplied to these phonons, change in frequency is observed, this is probably responsible for growth control of tissues or enzyme activities and even leads cancer. 

In next paper, Robert H Cole has presented a progressing report paper on mathematical interpretation of dielectric theory for the changes in DNA solution. The DNA structure is also represented by Watson Crick Helix. 

The subsequent paper show that change in energy of the biomolecules leads to the change in the enzyme activities and the analogy of the biophysical and biochemical processes in neuroscience with the electrochemical reactions.

The third part focuses on the thorough study of effects of the Radio Fields on the central nervous system and behavior. In the first paper by Chung Kwang Chou and Arthur William Guy, they have tried to find out the part of skull which determines the RF frequency, whether it is affected by the polarization of electric field, and the change in auditory response by using guinea pigs and cats and thus finding the analogy in the human body. The next paper brings about the threshold of the sensatiation to microwaves in rats. The paper by James C Lin, Aruthur W Guy and Lynn R Caldwell shows the operant responses of the rat carcasses (Skull) at various radiation strengths. The subsequent papers bring out the changes in behavior, dosimetry and stimuli in auditory responses on exposure to microwave.

The fourth part deals with the study on effects of microwave exposure which leads to temperature rise and causing pathology changes in animal body. 

The first paper shows the experiments on rats, rabbits and dogs on exposure to microwave thermal effects followed by cooling and the effects on eyes and testis thus, concluding the effects of the same on human body. 

The subsequent papers show the study of effects on endocrine, thyroid, pituitary changes due to exposure of microwaves of different energy and different exposure duration. The occurrence of vasodilation responses at various temperatures on exposure to microwaves is of significant emphasis in skin areas. The thermoregulatory responses on exposure to microwave post infrared exposure produce no changes in behavior. The immunity towards microwave exposure of 2450 MHz radiation for various duration are achieved by the body by lymphoid cells. Effects of microwave exposure on rabbits eye at frequencies of 2.45 to 10 GHz leads to opacity (cataract). 

A very significant study paper by Charles I Barron and Albert A Baraff shows how microwave exposures of radar effects heart, kidneys, liver, gastrointestinal and hemoarrhagic changes in respiratory system in animals and human body. 

Another paper by Charlotte Silverman reviews a study on Tri-services personnel occupationally exposed to radars causing nervous and behavioral effects, congenital anomalies, cancer etc. 

The last paper of this part by SM Michaelson shows the study of hazards associated with the development, association, operation and maintenance of radars and other radio-frequency emitting equipment on various body organs, tissues, and enzyme system on various power levels.

The fifth part reflects exposure, emission, susceptibility and medicine in diathermy, hyperthermia and diagnostic techniques on microwaves. 

The first paper illustrates the effect of deep tissue heating, and its applications. 

The next paper by JG Short and PF Turner states application of hyperthermic treatments as a choice of treatments or combination of other treatments on tumors based on their locations. 

The subsequent papers emphasize more on application of microwave radiations as a method of imaging techniques of kidneys, thermography as a means of detecting breast cancer by change in temperature of body tissues emitting thermal radiations, microwave applications in measuring neurochemical parameters, use of microwaves in thawing (upbringing to unfrozen state).

The sixth part is published with the articles covering on safety standards, the history and present state of potential hazards and microwave safety standards. The subsequent papers also put an emphasis on Biological effects and Dosimetric data for development of radio frequency safety. The data based on various RF emissions through equipment and places is also covered in the article.

The seventh part of the book covers the hazards of cardiac pacemakers due to electromagnetic interference and emission of radio frequency radiation. Other articles cover electromagnetic interference of pacemakers in dental environment by using pulse generator of various manufacturing companies.

This volume clearly brings out with various case studies, experiments, applications and illustrations on the Biological effects of Electromagnetic Radiations. 

The facts and figures help the reader to understand the functions of various systems designed and published in the articles in a simple way. 

However, the reader needs to have the requisite proficiency in electrical engineering and electromagnetic theory, mathematics, science and instrumentation and be conversant with relevant terminologies in order to better understand the effects of microwave and EM radiations on human beings and animals. 

Though published almost 30 years ago, this volume is a useful milestone reference book for those who want to delve into this fascination area of study. 

The Editor of this volume, John M Osepchuk was a consulting scientist at Raytheon Company Lexington, Massachusetts from 1950.  He received B.A. and M.A. degrees in Engineering Science and Applied Physics and a Ph.D. in Applied Physics, all from Harvard University.

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