REU June 2013
Biological Effects of Radio Waves
or
Are Cell Phones Dangerous to Your Health?
Tim Pratt, Instructor
Summer 2013
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The Known Danger
• Distracted driving – by you and by others
• In 2009:
• 5.5 million car crashes in the US
• 31,000 killed, 2 million injured
• 5,474 people killed in U.S. by accidents that
involved distracted driving
• 448,000 were injured
• The price we pay for using automobiles
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Cell Phones and Vehicle Accidents
• Cell phone a factor in 995 fatal accidents
• Also in 24,000 injuries
• Under-20 age group had the highest percentage
of distracted drivers
• 16% of under 20 years olds involved in fatal
crashes were distracted while driving
• The price we pay for using cell phones
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Radiation
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Radiation is divided into two categories:
Ionizing radiation
Alpha particles, Beta particles,
X rays, cosmic rays
Non-ionizing radiation
Light, including visible, Infra red and Ultra violet
Radio waves from ULF to millimeter waves
Also of interest:
60 Hz fields from power lines and other sources
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Ionizing Radiation
• Ionizing radiation causes changes to molecules
• Waves/particles have sufficient energy to knock
electrons out of molecules
• Can cause damage to biological materials
• CDRH is US body responsible for human
exposure
• Center for Devices and Radiological Health
places limits on acceptable exposure to X rays
• Also regulates exposure to laser sources
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Non-Ionizing Radiation
• Non-ionizing radiation covers entire EM
spectrum up to ultra violet light
• Light and radio waves do not have enough
energy to cause changes in molecules
• Many molecules – especially water – absorb
EM energy
• Absorption process is called dipole rotation
• Molecule behaves like electric dipole
• Rotates at incident frequency – dissipates
energy
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Known Effects of EM Waves
• Heating
• Incident radio and light waves are absorbed by
animal and human components
• Absorption varies greatly with material
• Water content closely related to absorption
• Effects observable with any microwave oven
• Example: Dried peas in water
• Water initially gets hot, peas don’t
• The miniature poodle case
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Penetration Depth
• Longer wavelengths penetrate more deeply
• At 100 MHz, 99% of energy is absorbed in a
distance of several centimeters
• At 2.4 GHz depth is ~ 1 cm
• For optical frequencies depth is ~ ½ mm
• Sunlight is powerful EM source
• > 300 W / m2 on sunny summer day
• Equal to 30 mW / cm2
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Safety Standards
• International standards set by World Health
Organization (WHO)
• National Standards set by government
departments or agencies and national
(independent) bodies
• CDRH in US
• National Radiological Protection Board in UK
• Department of Post and Telecommunications in
Japan
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International Exposure Levels
• Maximum permitted exposure
• UK
1.0 - 10 mW/cm2
• US, Canada, Japan,
0.2 – 1.0 mW/cm2
Germany
• Australia
0.2 mW/cm2
• Italy
0.05 mW/cm2
• Russia, Switzerland
0.002 – 0.01 mW/cm2
• Higher exposure may be permitted for short
period of time
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FCC Rules for Cell Phones
• Particular concern because half energy from
antenna is absorbed in head
• 900 MHz (AMPS) cell phones
• Tx power limit is around 0.5 watts
• 1.8 – 2.0 GHz (PCS) cell phones
• Limit is 0.3 W
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Cell Phones and Cancer
• Recent World Health Organization report called
cell phones a possible factor in cancer, along
with coffee, car exhaust …
• FCC statement:
• There is no scientific evidence to date that
proves that wireless phone usage can lead to
cancer or a variety of other health effects,
including headaches, dizziness or memory loss.
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About 48% of power from cell phone
transmitter is absorbed by user’s head
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Children and Cell Phones
Microwave radiation penetrates a child’s head
much further than an adult’s
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Research to Establish Biological Effects
• Sponsored by government agencies and
departments, independent boards, private
foundations
• Thousands of studies
• Hundreds of conclusions
• Particular concerns:
• Absorption of microwave energy by head when
using a cell phone
• Intense 60 Hz fields below high voltage power lines
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Researching Biological Effects
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Population Studies Epidemiological studies of groups of people
Individual Studies Animal and human research
Cell and Tissue Studies Cell and biological investigations
Molecular Level Studies Biochemical and molecularbiological
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Population Studies
• Compare groups of people exposed to radio
waves with non-exposed control group
• Exposed groups:
• Workers building radar and communication
systems
• Installation engineers
• People living near high power transmitters
• Children in schools near transmitters
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Population Studies
• Look for:
• General decline in health
• Specific conditions
• E.g. cancer, digestive illnesses, sleeplessness
• Results of Russian study:
• People working in factories where exposure to
radio waves and radar transmissions were less
healthy than general population
• Problem: What other factors might be involved?
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Russian Study
• Russian government took results of study
seriously
• Banned microwave ovens in 1976
• Reduced exposure standard from 10 mW/cm2
to 0.01 mW/cm2
• No readily available data on whether health of
workers improved
• No control groups reported
• Russians identified Radio Wave Sickness
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Individual Studies
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Typically conducted on rats, mice, guinea pigs
Place animals around a radiating antenna
Or in reduced power microwave oven
Set up control group in identical condition with
no radiation
• Compare general health of animals after 2, 4, 6
… many weeks
• Look for specific conditions: cancer, stroke,
heart arhythmia, other illnesses,
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Iindividual Studies
• Rats, mice and guinea pigs
Test group
Cell phone on
Control group
Cell phone off
Look for difference in health
Use mice and rats susceptible to cancer
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Individual Studies
• Example study on rats with GSM cell phone:
• Equivalent of 0.91 W Tx power
• Rats located around radiating antenna
• Two control groups used
• Experiment conducted for number of weeks
• No adverse effects found
• Doesn’t prove that cell phones are harmless to
humans
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Cell and Tissue Studies
• Cancer studies
• Use chemical agents to cause tumors
• Place animal in microwave oven for a while
(at low power)
• Set up control group with power off
• See if tumor grows faster in exposed animals
• Particular interest: brain tumors
• Technique not used on human subjects
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Biological Studies
• Put human brain tissue in a dish
• Repeat rat experiment
• Look for change in DNA – especially tumors
Control group
Cell phone off
Test group
Cell phone on
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Molecular Studies
• Place cell cultures in Petrie dishes
• Radiate some, use others for controls
• Look for differences at molecular level
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Other Studies
• Radio wave sickness
• Further studies of selected groups via interviews
and health reports
• Click effect – some people claim to hear a click
from pulse transmitters
• Heart problems - look for specific condition
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Conclusions on Studies
• Several independent groups have evaluated
many studies of all types
• Most get rejected as flawed, unscientific, or
poorly conducted
• Conclusions from all groups:
• There is no conclusive evidence that radio
waves at safety standard levels cause illnesses,
cancer, or other health hazards
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Conclusions - Conditional
• Are some individuals more susceptible to radio
waves than others?
• Are some tumors in some people sensitive to a
specific frequency?
• What effect do radio waves have on children?
• FCC says there are no known adverse effects
from cell phone use
• UK Radiological Protection Board recommends
that children be restricted from non-essential cell
phone use
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The Concern
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Powerful interests don’t want restrictions
E.g. Cell phone manufacturers and operators
Others would like to discover a problem
E.g. Trial lawyers would like a chance for a class
action law suit on brain tumors
• Thalidomide, Viox cases
• Then there’s the Internet …
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From the Internet …Hidden Hazards
• The Hidden Hazards Of Microwave Cooking
• By Anthony Wayne and Lawrence Newell
• Is it possible that millions of people are ignorantly
sacrificing their health in exchange for the convenience
of microwave ovens?
• Why did the Soviet Union ban the use of microwave
ovens in 1976?
• Who invented microwave ovens, and why?
• The answers to these questions may shock you into
throwing your microwave oven in the trash
• Ref:
http://www.mercola.com/article/microwave/hazards.htm
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Hidden Hazards
• Over 90% of American homes have microwave ovens
used for meal preparation
• Microwave ovens are convenient and energy efficient
• Very few homes or restaurants are without them
• People believe that microwave ovens don't have any
negative effect on either the food or their health
• They are wrong!
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Hidden Hazards
• If microwave ovens were really harmful, our government
would never allow them on the market, would they?
• Would they?
• We have stopped using ours based on the research
facts outlined in this article
• The purpose of this report is to show proof - evidence that microwave cooking is not natural, nor healthy
• Far more dangerous to the human body than anyone
could imagine …
• The microwave oven is sapping your life force …
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50 Hz and 60 Hz Electric Fields
• Similar concerns exist about exposure to 50 Hz
and 60 Hz electric fields from power lines
• Population studies in some places suggest a
problem, especially for children
• Sweden moved some schools from under power
lines after one study
• Conclusion from analysis of many studies:
• No conclusive evidence of health hazard
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50 Hz and 60 Hz Electric Fields
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How to get exposed to 50 / 60 Hz:
Sleep under an electric blanket (turned on)
Studies did reveal one interesting effect
Workers who came in contact with high voltage
lines were more likely to contract Lou Gherig’s
disease (ALS)
• ALS = amyotrophic lateral sclerosis
• Condition in which some nerves cease to
conduct – no known cure
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Lasers and the Human Eye
• Lasers radiate coherent radiation – a plane
wave front
• Lens in the eye can focus laser beam to one
micron spot
• Can burn a hole in the retina
• CDRH and EU have complex formulas limiting
maximum exposure
• Based on eye 10 or 20 cm away from laser
• Limit is microwatts at visible and near IR
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Conclusion
• After billions of dollars of research …
• No conclusive indication that EM waves or
50/60 Hz harm human health other than by
heating
• The research continues ….
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