Biolog Radio Waves-Dr Pratt (2)

8/11/2019 Biolog Radio Waves-Dr Pratt (2)

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Summer 2013 Tim Pratt 2012 1

REU June 2013

Biological Effects of Radio Waves

or

Are Cell Phones Dangerous to Your Health?Tim Pratt, Instructor


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http://jeffreyhill.typepad.com/.a/6a00d8341d417153ef014e89094ed4970d-popup


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The Known Danger

Distracted drivingby 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

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 Healthplaces 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 EMspectrum up to ultra violet light

Light and radio waves do not have enough

energy to cause changes in molecules Many moleculesespecially waterabsorb

EM energy

Absorption process is called dipole rotation

Molecule behaves like electric dipole Rotates at incident frequencydissipates

energy


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Known Effects of EM Waves

Heating

Incident radio and light waves are absorbed byanimal 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 dont

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 ~ mm

Sunlight is powerful EM source

> 300 W / m2on 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, 0.21.0 mW/cm2

Germany

Australia 0.2 mW/cm2

Italy 0.05 mW/cm2

Russia, Switzerland 0.0020.01 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

1.82.0 GHz (PCS) cell phones

Limit is 0.3 W


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Cell Phones and Cancer

Recent World Health Organization report calledcell phones a possible factor in cancer, alongwith coffee, car exhaust

FCC statement: There is no scientific evidence to date thatproves that wireless phone usage can lead tocancer 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 users head


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Children and Cell Phones

Microwave radiation penetrates a childs headmuch further than an adults


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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 whenusing a cell phone

Intense 60 Hz fields below high voltage power lines


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Researching Biological Effects

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 communicationsystems

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 lesshealthy 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

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

Doesnt prove that cell phones are harmless tohumans


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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 DNAespecially tumors

Test group

Cell phone on

Control group

Cell phone off


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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 effectsome people claim to hear a clickfrom 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 radiowaves than others?

Are some tumors in some people sensitive to aspecific frequency?

What effect do radio waves have on children?

FCC says there are no known adverse effectsfrom cell phone use

UK Radiological Protection Board recommendsthat children be restricted from non-essential cellphone use


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The Concern

Powerful interests dont 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 theres 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 ignorantlysacrificing 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 intothrowing 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

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 Gherigs

disease (ALS)

ALS = amyotrophic lateral sclerosis Condition in which some nerves cease to

conductno known cure


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Lasers and the Human Eye

Lasers radiate coherent radiationa 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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Biolog Radio Waves-Dr Pratt (2)

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