6704569 Microwave Hazards and Bio Effects

8/7/2019 6704569 Microwave Hazards and Bio Effects

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Department Of ECE

Institute of Engineering & Technology, Bhaddal

Assignment

Bio-Effects of Microwaves


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Bio-E ffects of Microwaves

Since the 18th century scientists have been intrigued by the interaction of electromagnetic

fields (EMFs) and various life processes. Attention has been focussed on EMFs indifferent frequency ranges, of which microwave frequency range forms an important part.

Microwaves are part of the electromagnetic spectrum and are considered to be thatradiation ranging in frequency from 300 million cycles per second (300 MHz) to 300

billion cycles per second (300 GHz), which correspond to a wavelength range of 1 m

down to 1 mm. This nonionising electromagnetic radiation is absorbed at molecular level

and manifests as changes in vibrational energy of the molecules or heat

Identifying and evaluating the biological effects of microwaves have been complex and

controversial. Because of the paucity of information on the mechanism of interaction

between microwave and biological systems, there has been a persistent view in physicaland engineering sciences, that microwave fields are incapable of inducing bioeffects

.other than by heating

Interaction of microwaves with biological systems.

Many biological systems can be expected to exhibit resonance behavior involving the

mechanical vibration of system elements.The natural frequencies of such resonanceswill, generally, bein the microwave frequency range. Some of these systems will be

coupled to the electromagnetic field by the charge distributionsthey carry, thus admitting

the possibility that microwave exposuresmay generate physiological effects in man and

other species. However,

such microwave excitable resonances are expected to be stronglydamped by interaction with their aqueous biological environment. Although those

dissipation mechanisms have been studied, the limitationson energy transfers that followfrom the limited coupling of theseresonances to the electromagnetic field have not

generally beenconsidered. We show that this coupling must generally be very small and

thus the absorbed energy is so strongly limited thatsuch resonances cannot affect biology

significantly even if thesystems are much less strongly damped than expected from basicdissipationmodels.

Biological hazards of microwave as well as low

frequencyExposure to microwave emissions and frequency radiations have an unpredictorynegative effect on the biological welfare of humans.

1. A breakdown of the life energy field in those who were exposed to microwave,

while in operation, with side effects to the humans for longer duration.


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2. A degeneration of cellular voltage parallels during the process of using the

apparatus, especially in blood & lymphatic errors.

3. A degeneration circuit breakdowns electrical nerve impulses within the junctionpotential of cerebrum.

4. A degeneration and breakdown of nerve electrical circuits and loss of energy

symmetry in the nervoplexuses both at the front & the rear of central andautonomic nervous system.

5. Loss of balance and circuiting of the bio electrical strengths within the ascending

reticular activating system (the system which controls the function ofconsciousness).

6. A long term cumulative loss of vital energies within the humans, animals and

plants that were located within a 500m radius of the operational equipment.

7. A destabilization and interruption in the production of hormones and maintenanceof hormonal balance in males and females.

8. long lasting residual effects of magnetic deposits were located throughout the

nervous systems and lymphatic systems.

9. marked by higher levels of brain in wave disturbance in alpha, theta and deltawave signal patterns of persons exposed to microwaves emission fields.

10. Because of this brain wave disturbance, negative psychological effects were notedincluding loss of memory, loss of ability to concentrate.

Interaction of microwaves with biological systems.

Many biological systems can be expected to exhibit resonance behavior involving themechanical vibration of system elements.The natural frequencies of such resonances

will, generally, bein the microwave frequency range. Some of these systems will be

coupled to the electromagnetic field by the charge distributionsthey carry, thus admittingthe possibility that microwave exposuresmay generate physiological effects in man and

other species. However,such microwave excitable resonances are expected to be strongly

damped by interaction with their aqueous biological environment. Although those

dissipation mechanisms have been studied, the limitationson energy transfers that followfrom the limited coupling of theseresonances to the electromagnetic field have not

generally beenconsidered. We show that this coupling must generally be very small and

thus the absorbed energy is so strongly limited thatsuch resonances cannot affect biologysignificantly even if thesystems are much less strongly damped than expected from basic

dissipationmodels

There are two frequencies

Low frequency 400khz

Microwave 10ghz

At low frequency and microwave, the electric and microwave fields are

simultaneously present if there is an electric field then there is a coupled magnetic

field and vice versa.


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Only the fields inside tissue and biological bodies can possibly interact with these the

biological effects of radio freq\ microwave do not depend solely on the external

power density. They depend on the dielectric field inside of the tissue or the body.Heating effect of microwaves can lead to significant physiological effects.

Microwave radiations interacts with cell membranes to induce functional alterations

in membrane components.An important consideration in estimating the effect of dosimetry in the coupling of rf

and microwave radiations to biological systems. This depends on the orientation of

subject relative to the field, and on its dimensions relative to the wavelength.Coupling to a body is maximal when its long axis is oriented parallel to electric field

and when its length is similar to the wavelength therefore maximum absorption for an

exposed subject is frequency dependent and occurs at app. 40mhz for an

average( electrically grounded) man, 600-700mhz for a rat and 2500mhz for a mousewhole body.

As frequency increase and wavelength decrease power absorption per unit mass of

tissue increases and penetration decreases. Above 10ghz, absorption would be

expected to be largely confined to skin.A relatively constant amount of body tissue when exposed then cumulative effect

could occur and lead to eventual breakdown of homeostasis and adverse healthconsequences.

It could also affect blood brain barrier, morphology, electrophysiology metabolism.

Diathermy

In the natural sciences, the term diathermy means "electrically induced heat" and is

commonly used for muscle relaxation. It is also a method of heating tissueelectromagnetically or ultrasonically for therapeutic purposes in medicine.
http://en.wikipedia.org/wiki/Natural_scienceshttp://en.wikipedia.org/wiki/Natural_sciences


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Benefits

Diathermy can be used to treat arthritis,bursitis, and other conditions involving stiff,

painful joints. It is also used to treat pelvic infections and sinusitis. A benefit ofdiathermy is that it is a painless procedure that can be administered at a clinic. Also, if the

treatment relieves pain, then patients can discontinue pain killers and escape their highcost and side effects.

Description

Diathermy involves heating deep muscular tissues. When heat is applied to the painful

area, cellular metabolism speeds up and blood flow increases. The increased metabolism

and circulation accelerates tissue repair. The heat helps the tissues relax and stretch, thusalleviating stiffness. Heat also reduces nerve fiber sensitivity, increasing the patient's pain

threshold.

There are three methods of diathermy. In each, energy is delivered to the deep tissues,

where it is converted to heat. The three methods are:

Shortwave diathermy. The body part to be treated is placed between two capacitorplates. Heat is generated as the high-frequency waves travel through the body

tissues between the plates. Shortwave diathermy is most often used to treat areas

like the hip, which is covered with a dense tissue mass. It is also used to treat

pelvic infections and sinusitis. The treatment reduces inflammation. The FederalCommunications Commission regulates the frequency allowed for short-wave

diathermy treatment. Most machines function at 27.33 megahertz.

Ultrasound diathermy. In this method, high-frequency acoustic vibrations are usedto generate heat in deep tissue.

Microwave diathermy. This method uses radar waves to heat tissue. This form is

the easiest to use, but the microwaves cannot penetrate deep muscles.
http://usnews.healthline.com/adamcontent/arthritishttp://usnews.healthline.com/adamcontent/arthritishttp://usnews.healthline.com/adamcontent/bursitishttp://usnews.healthline.com/adamcontent/joint-painhttp://usnews.healthline.com/adamcontent/sinusitishttp://usnews.healthline.com/adamcontent/sinusitishttp://usnews.healthline.com/adamcontent/ultrasoundhttp://usnews.healthline.com/adamcontent/arthritishttp://usnews.healthline.com/adamcontent/bursitishttp://usnews.healthline.com/adamcontent/joint-painhttp://usnews.healthline.com/adamcontent/sinusitishttp://usnews.healthline.com/adamcontent/ultrasound


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Diathermy is also used in surgical procedures. Many doctors use electrically heated

probes to seal blood vessels to prevent excessive bleeding. This is particularly helpful in

neurosurgery and eye surgery. Doctors can also use diathermy to kill abnormal growths,such astumors, warts, and infected tissues.

Microwave Diathermy

Treatment Settings

Micro-wave diathermy waves used for treatment is of Wave length - 12.25 cm

Frequency - 2,450 cycles/sec

Production of Waves

The waves are obtained by heating special type of valve called Magnetron. The output iscarried to a small aerial and microwaves are emitted.

Where useful?

1. Pain2. Bacterial infection

3. Septic fingers

4. Boils

5. Abscess

Where it should not be used?

1. Cancer

2. Tuberculosis of Bone

3. Recent exposure to X-rays4. Defective blood circulation (In cases likeDiabetes)

Advantages

Pain is relieved

1. Healing ofinfectionsis faster

2. Aids in relaxation

Disadvantages

1. Burns
http://usnews.healthline.com/galecontent/ophthalmologic-surgeryhttp://usnews.healthline.com/adamcontent/tumorhttp://usnews.healthline.com/adamcontent/tumorhttp://usnews.healthline.com/adamcontent/wartshttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://usnews.healthline.com/galecontent/ophthalmologic-surgeryhttp://usnews.healthline.com/adamcontent/tumorhttp://usnews.healthline.com/adamcontent/wartshttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htmhttp://medindia.net/Patients/patientinfo/physiotherapytypes_microwave.htm


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2. Injuries to eyes

Short Wave Diathermy

Short Wave diathermy current is a high frequency alternating current. The heat energy

obtained from the wave is used for giving relief to the patient.

Its frequency is 27,120,000 cycles per second and the wavelength is 11 metre.

Circuit Description:Diathermy machine consist o f two main circuits ;an oscillating

circuit,which produces the high frequency current and a patient circuit which is

connected to the oscillating circuit and through which the electrical energy is transferredto the patient.

Types of Applications

1. The condenser field method (commonly used)

2. Cable method

Where useful?

1. Inflammation of shoulder joint

2. Inflammation of Elbow Joint (Tennis Elbow)

3. Degeneration of joints of neck (Cervical Spondylosis)4. Degeneration of joints like knee and hip (Osteoarthritis)

5. Ligament Sprains in knee joint

6. Low Back Ache7. Plantar fascitis (Heel Pain)8. Sinusitis

Where it should not be used?

General

1. High Fever2. Fluctuating Blood Pressure

3. Very sensitive Skin4. Persons with Untreated Fits5. Persons using Cardiac Pace Maker

6. Severe kidney and heart problems

7. Pregnant Women8. Mentally Retarded Individuals

9. Tuberculosis of Bone

10. Malignant cancer


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Ultrasonic Diathermy

It's an electromagnetic wave different from sound waves.

The frequencies of waves employed for medical purposes are between 5,00,000 and

3,000,000 cycles/sec.

Generation of Ultrasonic waves

Ultrasonic waves are generated by vibration of a Crystal mounted on a special head.

Treatment Time

Initial Stage - 3 to 4 min

Severe Stage - 6 to 8 min

Where useful?

1. Inflammation of Elbow Joint (Tennis elbow)2. Plantar fascitis(Heel pain)

3. Shortening of Muscle or Ligament

4. Inflammation of tendons(For eg Supraspinatus tendnitis)

5. Ligament sprain(For eg Lateral Ligament sprain of ankle)6. Unhealed scars

Where should it not be used?

1. Avoidance to specialised structures such as eyes, ears,ovaries or testes.

2. Growing ends of bones3. Uterus of pregnant women

4. Areas with poor blood supply (In case of Diabetes)

5. Cancer

Advantages

1. Relief of pain2. Healing of Soft tissues (Ligament)

3. Healing of unhealed scars

Disadvantages

1. Burns2. Cavitation (Damage to bones)


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3. Overdose

USES

Heating uses

Ultrasonic diathermy refers to heating of tissues by ultrasound for the purpose oftherapeutic deep heating. No tissue is ordinarily damaged hence it is generally used in

biomedical applications.

Electric diathermy uses high frequency alternating electric or magnetic fields, sometimes

with no electrode or device contact to the skin, to induce gentle deep tissue heating byinduction. Again, no tissue is ordinarily damaged

Surgical uses

Surgical diathermy is usually better known as "electrosurgery." (It is also referred tooccasionally as "electrocautery", but see disambiguation below). Electrosurgery and

surgical diathermy involve the use of high frequency A.C. electrical current insurgery as

either a cutting modality, or else to cauterize small blood vessels to stop bleeding. This

technique induces localized tissue burning and damage, the zone of which is controlledby the frequency and power of the device. Some sources[1] insist that electrosurgery be

applied to surgery accomplished by high frequency A.C. cutting, and that

"electrocautery" be used only for the practice of cauterization with heated nichrome wirespowered by D.C. current, as in the handheld battery-operated portable cautery tools.

Electrosurgery is the application of a high-frequency electric current to human (or otheranimal) tissue as a means to remove lesions,staunchbleeding, or cut tissue.

Electrosurgery can be used to cut,coagulate,desiccate, orfulgurate tissue.[1][2][3][4][5][6][7]

(These terms are used in specific ways for this methodology-- see below). Its benefits

include the ability to make precise cuts with limited blood loss.

In electrosurgerical procedures, the tissue is burned by an electrical current. Although

electrosurgical devices may be used for the cauterizationof tissue in some applications(as for example during hemorrhoid surgery), electrosurgery is usually used to refer to a

quite different method than that used by many dedicatedelectrocautery devices. The

latter uses heat conduction from a hot probe heated by a direct current (much in the

manner of a soldering iron), whereas electrosurgery uses alternating current to directlyheat the tissue itself (diathermy), while the probe tip remains relatively cool.

Electrosurgery is commonly used for such dermatological procedures as removal ofskin

tags, removal/destruction of benign skin tumors, and the removal ofwarts. It is now oftenpreferred by dermatologists over laser surgery and cryosurgery for several procedures.
http://en.wikipedia.org/w/index.php?title=Ultrasonic_diathermy&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Electric_diathermy&action=edit&redlink=1http://en.wikipedia.org/wiki/Electrosurgeryhttp://en.wikipedia.org/wiki/Cauterization#Electrocauteryhttp://en.wikipedia.org/wiki/Surgeryhttp://en.wikipedia.org/wiki/Surgeryhttp://en.wikipedia.org/wiki/Diathermy#_note-0http://en.wikipedia.org/wiki/Electrosurgeryhttp://en.wikipedia.org/wiki/Cauterization#Electrocauteryhttp://en.wikipedia.org/wiki/Nichromehttp://en.wikipedia.org/wiki/Lesionshttp://en.wikipedia.org/wiki/Staunchhttp://en.wikipedia.org/wiki/Staunchhttp://en.wikipedia.org/wiki/Staunchhttp://en.wikipedia.org/wiki/Coagulatehttp://en.wikipedia.org/wiki/Coagulatehttp://en.wikipedia.org/wiki/Desiccatehttp://en.wikipedia.org/wiki/Desiccatehttp://en.wikipedia.org/wiki/Fulgurationhttp://en.wikipedia.org/wiki/Fulgurationhttp://en.wikipedia.org/wiki/Electrosurgery#_note-hainer1991http://en.wikipedia.org/wiki/Electrosurgery#_note-hainer2002http://en.wikipedia.org/wiki/Electrosurgery#_note-hyfrecatorhttp://en.wikipedia.org/wiki/Electrosurgery#_note-boughtonhttp://en.wikipedia.org/wiki/Electrosurgery#_note-bouchierhttp://en.wikipedia.org/wiki/Electrosurgery#_note-oringerhttp://en.wikipedia.org/wiki/Electrosurgery#_note-Reidenbachhttp://en.wikipedia.org/wiki/Cauterizationhttp://en.wikipedia.org/wiki/Cauterizationhttp://en.wikipedia.org/wiki/Hemorrhoidhttp://en.wikipedia.org/wiki/Electrocauteryhttp://en.wikipedia.org/wiki/Electrocauteryhttp://en.wikipedia.org/wiki/Heat_conductionhttp://en.wikipedia.org/wiki/Diathermyhttp://en.wikipedia.org/wiki/Skin_tagshttp://en.wikipedia.org/wiki/Skin_tagshttp://en.wikipedia.org/wiki/Tumorshttp://en.wikipedia.org/wiki/Wartshttp://en.wikipedia.org/w/index.php?title=Ultrasonic_diathermy&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Electric_diathermy&action=edit&redlink=1http://en.wikipedia.org/wiki/Electrosurgeryhttp://en.wikipedia.org/wiki/Cauterization#Electrocauteryhttp://en.wikipedia.org/wiki/Surgeryhttp://en.wikipedia.org/wiki/Diathermy#_note-0http://en.wikipedia.org/wiki/Electrosurgeryhttp://en.wikipedia.org/wiki/Cauterization#Electrocauteryhttp://en.wikipedia.org/wiki/Nichromehttp://en.wikipedia.org/wiki/Lesionshttp://en.wikipedia.org/wiki/Staunchhttp://en.wikipedia.org/wiki/Coagulatehttp://en.wikipedia.org/wiki/Desiccatehttp://en.wikipedia.org/wiki/Fulgurationhttp://en.wikipedia.org/wiki/Electrosurgery#_note-hainer1991http://en.wikipedia.org/wiki/Electrosurgery#_note-hainer2002http://en.wikipedia.org/wiki/Electrosurgery#_note-hyfrecatorhttp://en.wikipedia.org/wiki/Electrosurgery#_note-boughtonhttp://en.wikipedia.org/wiki/Electrosurgery#_note-bouchierhttp://en.wikipedia.org/wiki/Electrosurgery#_note-oringerhttp://en.wikipedia.org/wiki/Electrosurgery#_note-Reidenbachhttp://en.wikipedia.org/wiki/Cauterizationhttp://en.wikipedia.org/wiki/Hemorrhoidhttp://en.wikipedia.org/wiki/Electrocauteryhttp://en.wikipedia.org/wiki/Heat_conductionhttp://en.wikipedia.org/wiki/Diathermyhttp://en.wikipedia.org/wiki/Skin_tagshttp://en.wikipedia.org/wiki/Skin_tagshttp://en.wikipedia.org/wiki/Tumorshttp://en.wikipedia.org/wiki/Warts


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Electrosurgery is performed using a device called an Electrosurgical Generator,

sometimes referred to as an RF Knife.

6704569 Microwave Hazards and Bio Effects

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