The presentation proves beyond any doubt, the harmful affects of microwaves and radio frequency waves on humans and other living beings

1. Human Body and
Implant Material
Interaction with Radio-
Frequency and
Microwave Radiation
Dr. K. Padmanabhan
Professor
Mechanical Engineering
SVCE, Sri Perumbudur

2. There were impregnations,
there were powers, there
was energy below, there
was impulse above
-Rig Veda, Existence, 10.129.5

3. Radiation
Natural Man Made
Ionizing
Non- ionizing
Radio Frequency
MicrowavesX Rays U V
Freq. domain of RF : 1 Hz to 300 GHz

4. Microwaves
Designation Frequency range
L band 1 to 2 GHz
S band 2 to 4 GHz
C band 4 to 8 GHz
X band 8 to 12 GHz
Ku band 12 to 18 GHz
K band 18 to 26.5 GHz
Ka band 26.5 to 40 GHz
Q band 30 to 50 GHz
U band 40 to 60 GHz
V band 50 to 75 GHz
E band 60 to 90 GHz
W band 75 to 110 GHz
F band 90 to 140 GHz
D band 110 to 170 GHz (Hot)

5. Non-Ionizing Radiation
Does not have sufficient
quantum energy to ionize an
atom.
i.e. They cannot eject electrons
from an atom or molecule to
produce a positively charged
core or ion.

6. RF and Microwave
Range
The radiation contributes to random
molecular motion which can be
described as thermal energy.
Chemical and physiological effects
occur as a result of thermal energy
absorption.
An indirect effect !

7. Criteria for Absorption
There must be quantum energy
level pairs which match the
photon energy of the radiation.
Must have high dielectric
constant i.e. high relative
permittivity.

8. For Low Absorption
Low dielectric constant and low
relative permittivity means low
loss,higher transmission,low
capacitance and low absorption.
This is better for health.
………. But

9. Values of Material Parameters (real part of relative permittivity έr
, Effective conductivity
σeff
and density ρ ) at 900 MHz.
Material έr
σeff
(S/m) ρ kg/m3
Tissue-equivalent
liquid (TEL)
42.50 0.850 1000
Muscle 55.95 0.969 1050
Bone 16.62 0.242 1645
Fat 05.00 0.025 1100
Skin 41.40 0.867 1090
Nylon 6 cast
3.20 –
12.0
- 1120 – 1170

10. Values of Material Parameters (real part of relative permittivity έr
, Effective conductivity
σeff
and density ρ ) at 900 MHz.
Material έr
σeff
(S/m) ρ kg/m3
Nylon 66 Extruded 3.20 – 5.00 - 1130 – 1350
Nylon 666 Un reinforced 2.90 – 10.0 - 1030 – 1710
Polycarbonate (unfilled) 3.17 - ~1200
Polycarbonate (30%
glass)
3.35 - ~1430
Esters 3.30 – 4.40 - ~1050 – 1390
UHMWPE 2.30 - 945
Acrylic resin (cast) 2.70 - 1180 – 1190
Poly methyl
methacrylate (PMMA)
3.20 – 3.70 - 1190

11. Plastic human-The Myth
An all fibre reinforced plastic, reinforced
plastic or plastic human would have
been healthier against microwave
exposure !
Also Hydroxy Apatite (HAP) which is a
bone substitute is lower loss compared
to bone!

12. Resonance
Resonance occurs when exposed
radiation ( microwaves) has
wavelengths comparable to the
dimensions of trunk ,waist and limbs.
This happens at RF frequencies of ~
300 MHz which is never used in
communication,normally.

13. Resonance
An adult head,babies,macaques and
mature fetuses resonate at ~ 1 GHz.
Many cell phones operate at 850/900 MHz !

14. Skin Effect
At 3 GHz and above one
experiences skin effect where the
transmission is restricted to the
surface of the body.
Analogy from electricity power
transmission !

15. Thermal Effects
Quantification of thermal effects!
Specific Absorption Rate (SAR)
measures rate at which
electromagnetic energy is absorbed
by exposed object in Watts per
Kilogram (W/Kg).
Safety exposure limits !

16. Thermal Effects
30 minute exposure with an SAR of
1 W/Kg caused an averaged
human body to heat by 1ºC.
In cell phone usage up to 2 W/Kg is
encountered !

17. More Thermal Effects
At 2.65 GHz, for an SAR of 4 W/Kg retinal
and corneal damages are observed in
monkeys. SAR of 15W/Kg for half an hour
produced severe malformations !
Pulsed fields appear to be more detrimental
that continuous fields as they are normally
generated with more field strength!
Pulsed radiation not used in mobile
communication !

18. A comparison
Muscular people heat more than
thin people as muscle absorbs
more microwaves!

19. Attenuation
Attenuation as a measure of absorption!
Most of the power from a mobile phone
is absorbed with in a few centimetres of
the head!
Skin Depth= depth at which field
strength reduces to 1/exponential of its
value.

20. Dosimetry
Dosimetry-effect of radiation
distribution studies.
Attenuation is less in patients with
plastic ,RP,FRP implants.
It is preferable not to use ceramics
and CMCs as implant materials!

21. Anechoics
Anechoic Phenomena and
building absorption.
Ghost Signals Correction.
Building Warm Up.

22. Absorption
Power absorbed by the body is
ultimately decided by the field strength
expressed in volts/metre.
Electric field Sq.root of power.
RF power amplifiers up to 2 KW in the
frequency range of 10KHz to 8GHz
generate field strength of 200V/m.

23. Standards
WHO/ European Union recommend
up to 41.2V/m.
More would increase occurrence of
Leukemia.

24. Standards
NRPB: National Radiological
Protection Board of UK have listed
influence on
cancer,impairment of
reproduction,neurobehavioural
effects,cardiovascular effects,tumor,cognition
neurotransmitter effects,sleep pattern
,pregnancy, hypersensitivity and mood states.

25. Near field and far field effects
General public and occupational
exposure !
Head ache,parasthesiae ,diarrhea,
malaise and lassitude.
Occupational  Skin burns.

26. The Fatigue Analogy
Field
Strength/
Radiation
Power
Level
No. of cycles to failure (N)
Fatigue
Strength/
Endurance
Limit
Fatigue of exposure to pulsed vs continuous fields ?

27. Standards and Regulations
Occupational and general public
covering pulsed and continuous
radiation and acceptable levels!
ANSI/IEEE C.95 Series.
National Council on Radiation
Protection and Measurements
(NCRP,1986).

28. Standards and Regulations
The American Conference on
Governmental Industrial Hygienists
(ACGIH,1993).
The National Radiological Protection
Board (NRPB,1993).
The International Radiation Protection
Association (IRPA,1993).

29. Standards and Regulations
US Department of Labour,
Occupational Safety and Health
Administration (OSHA).
Federal Communication Commission
(FCC).
The Environmental Protection Agency
( EPA,USA).

30. Standards and Regulations
The International Commission on Non-
Ionizing Radiation Protection (ICNIRP).
The National Institute for Occupational
Safety and Health (NIOSH, USA).
The Australian Radiation Protection and
Nuclear Safety Agency (ARPANSA).
Health Protection Agency Standards
(HPA, Britain).

31. Standards and Regulations
Threshold SAR of 4 W/kg averaged
over the whole body above which
adverse health effects occur.
Most of the above standards have
determined a maximum field strength
not exceeding 10 V/m.
However, WHO/ICNIRP recommends
up to 41.2 V/m.

32. Types of Communication
The standards and regulations hold
good to TDMA,FDMA,CDMA, GPRS
( General Packet Radio service) and
GSM ( Global System for Mobile
Communication ) in the 800 MHz to 2
GHz operating range.
Some of the new cordless phones
operate at 2.45 GHz.

33. Standards and Regulations
There are two sets of limits for
occupational and general public
exposures.
The occupational environment has an
acceptable power limit of up to five
times the non-occupational environment
for frequencies up to 3 GHz.

34. Stark Realities
Multiple effects not understood properly.
Like living near a transmission
mast/mobile tower,being
pregnant,operating microwave ovens,
using RF amplifiers ,cordless and cell
phones extensively !

35. Indian Scenario
Vertical and Horizontal growth of cities.
When more people use mobile
phones,power can be reduced but only
up to a certain population density.
There is an optimum.
This rule doesn’t work for large public
gatherings where absorption by
individuals ruins reception.

36. Vertical and Horizontal

37. Demography
Demographic problems are different in
India due to the optimum curve of
power vs population density being
different.
Studies have to be conducted on
optimum power usage and the influence
of multiple effects,interference and
jamming

38. Demography
Further as building densities are heavier
and we have not built anechoic
buildings, EMI ( Electromagnetic
interference) studies gain prominence.
Japanese model for the EMI shielded
buildings and anechoic buildings.
Remember! Anything absorbs/reflects.

39. National Policy
Demographic problems, exposure
levels and safety limits have to be
addressed by the Ministry of
Communications and IT and Ministry of
Health and Family welfare
A national policy has to be evolved
before someone slowly gets skinned
alive!

40. The Rig Veda Again
There were impregnations, there
were powers, there was energy
below, there was impulse above
-Rig Veda, Existence, 10.129.5

41. Thank You