2012/06/05

Electro Magnetic Field (EMF) - Hazardous to Our Health?(from Mercola.com)

http://emf.mercola.com/sites/emf/emf-dangers.aspx


















Can electromagnetic fields (EMF)
from power lines, home wiring, airport and military radar, substations,
transformers, computers and appliances cause brain tumors, leukemia,
birth defects, miscarriages, chronic fatigue, headaches, cataracts,
heart problems, stress. nausea, chest pain, forgetfulness, cancer and
other health problems?

Numerous studies have produced contradictory results, yet some experts are convinced that the threat is real.

Dr. David Carpenter, Dean at the School of Public Health, State
University of New York believes it is likely that up to 30% of all
childhood cancers come from exposure to EMFs. The Environmental
Protection Agency (EPA) warns "There is reason for concern" and advises prudent avoidance".

Martin Halper, the EPA's Director of Analysis and Support says "I
have never seen a set of epidemiological studies that remotely
approached the weight of evidence that we're seeing with EMFs. Clearly
there is something here."

Concern over EMFs exploded after Paul Brodeur wrote a series of
articles in the New Yorker Magazine in June 1989. Because of Paul
Brodeur's reputation. his articles had a catalytic effect on scientists,
reporters and concerned people throughout the world.

In November 1989, the Department of Energy reported that "It has now
become generally accepted that there are, indeed, biological effects due
to field exposure."

The EMF issue gained more publicity in 1990 when alarming reports
appeared in Time, the Wall Street Journal, Business Week and popular
computer publications. ABC's Ted Koppel and CBS's Dan Rather both aired
special segments on EMFs.

In addition to the long-term health concerns, buying a house with
high fields will be an economic disaster. In a few years, when power
line radiation is as well known as asbestos and radon, a house with high
fields will be practically impossible to sell. Already there are
hundreds of lawsuits regarding EMFs and property devaluation.


EPA Says the Threat Is Real



By 1990, over one hundred studies had been conducted worldwide. Of
these, at least two dozen epidemiological studies on humans indicated a
link between EMFs and serious health problems. In response to public
pressure, the Environmental Protection Agency IEPA) began reviewing and
evaluating the available literature.

In a draft report issued in March 1990, the EPA recommended that EMFs
be classified as a Class B carcinogen -- -a "probable human carcinogen
and joined the ranks of formaldehyde, DDT, dioxins and PCBs.

After the EPA draft report was released, utility, military and
computer lobbyists came down hard on the EPA. The EPA's final revision
did NOT classify EMFs as a Class B carcinogen Rather, the following
explanation was added:"

At this time such a characterization regarding the link between
cancer and exposure to EMFs is not appropriate because the basic nature
of the interaction between EMFs and biological processes leading to
cancer is not understood."

Curiously, this rather unusual logic appears on the same page as the
following: "In conclusion, several studies showing leukemia, Iymphoma
and cancer of the nervous system in children exposed to supported by
similar findings in adults in several/ occupational studies also
involving electrical power frequency exposures, show a consistent
pattern of response that suggest a causal link. "

When questioned about the contradictory nature of these statements,
the EPA responded that it was "not appropriate" to use the probable
carcinogen label until it could demonstrate how EMFs caused cancer and
exactly how much EMF is harmful.

This explanation does not satisfy many critics who claim that the
EPAs upper management was influenced by political and economic
considerations exerted by utility, computer and military lobbyists.


How Do I Measure EMFs?



A Gauss is a common unit of measurement of magnetic field strength. A
Gauss meter is an instrument which measures the strength of magnetic
fields. Inside a Gauss meter there is a coil of thin wire, typically
with hundreds of turns. As a magnetic field radiates through the coil,
it induces a current, which is amplified by the circuitry inside the
Gauss meter.

Gauss meters may vary in the strength of the magnetic field they are
capable of measuring. A meter used for measuring EMFs from power lines,
transformers, substations and appliances around the home, for example,
should be able to measure as low as .1 mg.

Gauss meters vary widely in price and accuracy. Meters have either a
single axis coil or a triple axis coil. Single axis meters are much
simpler than triple axis meters to manufacture and thus, are less
expensive.

To use a single axis meter you must point the meter's one sensor in
three directions -- -the x, y and z axis. Then, you combine the three
readings in a mathematical equation to calculate the combined field
strength. Obviously, its far easier and more accurate to use a 3-axis
meter. Triple axis Gauss meters are quite accurate, but they are also
more expensive.

Another thing to watch out for when purchasing or renting a Gauss
meter is whether or not it is frequency weighted. Most meters will read
the same EMF strength no mater what the frequency.

As the human body appears to be sensitive to both the field strength
AND the frequency, Gauss meters used for biological purposes should be
"frequency weighted".

This means that if the field is different than 60 Hz the meter will
consider the frequency and use it in calculating and displaying the
EMF's strength. This feature is why frequency weighted meters will show a
higher EMF reading than those meters typically used by electricians and
engineers.


Power Lines



An enormous amount of electricity is created at power generating
stations and sent across the country through wires that carry high
voltages. All power lines radiate electromagnetic fields.
The question is: how much are the power lines near YOUR home radiating?
The amount of EMFs coming from a power line depends on its particular
configuration. Power companies know which power line configurations are
best for reducing EMFs but most don't feel the evidence supports costly
changes in the way they deliver electricity.


Substations



A substation is an assemblage of circuit breakers, disconnecting
switches and transformers designed to substations have been blamed for
causing cancer clusters among nearby residents. Paul Brodeur wrote about
several such cancer clusters in the July 9, 1990 issue of the New
Yorker Magazine.


Transformers



A key component of a utility's electrical distribution network
depends upon numerous, small transformers mounted on power poles. A
transformer looks like a small metal trash can, usually cylindrical.

Even when the electrical service is underground, you will often see a
metal box (usually square} located on the ground near the street. Many
people don't realize that when they see a transformer, the power line
feeding the transformer is 4000 to 13,800 volts.

The transformer then reduces the voltage to the 120/240 volts needed
by nearby homes. Since these transformers can be seen in almost every
neighborhood, they are a source of concern.

EMFs near a transformer can be quite high, but due to its small
structure, the field strength diminishes rapidly with distance, as it
does from any point source. For this reason, having a transformer
located near your home is usually not a major source of concern,
although just to make sure, everyone should measure the field strength
around it.


Home Wiring



If your home has high EMF readings, it is important to determine the
sources of the EMF so that remedial action can be taken, if possible.
Many times a particular room will have a higher EMF reading. Check to
see if the electricity is coming into the house on the wall outside that
room. When this is the case, it is usually a good idea to block off
that room and only use it for storage purposes.

Sometimes, the source of a high magnetic field is incorrect wiring.
If you suspect that your home is wired improperly, obtain the services
of a licensed electrician. Warning: Do not touch electric wires, even if
you think the current is turned off. If you need to disconnect
electrical circuits to determine the source of magnetic fields, you
should call a licensed electrician.


Computers



Computers are a complicated subject. Know this: EMFs radiate from all
sides of the computer. Thus, you must not only be concerned with
sitting in front of the monitor but also if you are sitting near a
computer or if a computer is operating in a nearby room.

The Swedish safety standard, effective 711/90, specifies a maximum of
0.25 mG at 50 cm from the display. Many US manufactured computers have
EMFs of 5 - 100 mG at this distance. And know this too: the screens
placed over monitors do NOT block EMFs. Not even a lead screen will
block ELF and VLF magnetic fields.

Space does not permit a more thorough discussion of computers. If you use a computer, it is important that you

measure your EMF exposure with a Gauss meter and review the literature concerning the health impacts of computer use.


Electric Blankets and Waterbeds



Electric blankets create a magnetic field that penetrates about 6-7
inches into the body. Thus it is not surprising that an epidemiological
study has linked electric blankets with miscarriages and childhood
leukemia.

This pioneering work was performed by Dr. Nancy Wertheimer and Ed
Leeper, who originally discovered that magnetic fields were linked to
childhood leukemia. Similar health effects have been noted with users of
many electric blankets and waterbed heaters will emit EMFs even when
turned off.

The devices must be unplugged to delete the EMF exposure
Additionally, there is the issue regarding the vibrations that are
generated by sleeping on standing water. There is less hard data in this
area but some experts are concerned about the consequences.


Electric Clocks



Electric clocks have a very high magnetic field, as much as 5 to 10
mG up to three feet away. If you are using a bedside clock, you are
probably sleeping in an EMF equivalent to that of a powerline Studies
have linked high rates of brain tumors with chronic exposure to magnetic
fields, so it is wise to place all clocks and other electrical devices
(such as telephones and answering devices) at least 6 feet from your
bed.


Fluorescent Lights



Fluorescent lights produce much more EMFs than incandescent bulbs. A typical fluorescent lamp of a office

ceiling have readings of 160 to 200 mg 1 inch away.


Microwave Ovens and Radar



Microwave ovens and radar from military installations and airports
emit two types of radiation -- microwave and ELF. Microwaves are
measured in milliwatt per centimeter squared (mW/cm2) As of 1/1/93, the
U.S. safety limit for microwave exposure is 1 mW/cm2, down from a
previous 10 mW/cm2. The Russian safety limit is .01 mW/cm2. All
microwave ovens leak and exceed the Russian safety limit. In addition,
recent Russian studies have shown that normal microwave cooking coverts
food protein molecules into carcinogenic substances.

When measuring microwaves from military and airport radar sources,
100% accurate readings can only be found with extremely expensive
digital peak-hold meters. Why? Because analog devices begin to drop
their reading immediately after the radar sweep passes. Thus, while an
analog meter can show whether or not you are being exposed to radar
EMFs, analog meters can't show your true exposure. Although thousands of
dollars to purchase, digital-hold meters capable of accurately
detecting radar EMFs can be rented for several hundred to over a
thousand dollars per month.


Telephones and Answering Machines



Telephones can emit surprisingly strong EMFs, especially from the
handset. This is a problem because we hold the telephone so close to our
head. Place the Gauss meter right against the ear piece and the mouth
piece before buying a phone.

Some brands emit no measurable fields and others emit strong fields
that travel several inches....right into your brain. Answering machines,
particular those with adapter plugs (mini-transformers), give off high
levels of EMFs.


Electric Razors and Hair Dryers



Electric razors and hair dryers emit EMFs as high as 200 to 400 mG.
This seems alarming, but we don't know if this is worse (or better) than
a chronic exposure to a 2-3 mG field. Some EMF consultants recommend
that hair dryers not be used on children as the high fields are held
close to their rapidly developing brain and nervous system.



Prudent Avoidance



Electricity is an inseparable part of our modern day society. This
means that EMFs will continue to be all around us. But as Discover
Magazine postulated, aside from making our life easier, is electricity
also making our lives shorter?

Most experts agree that limited, non-chronic exposure to EMFs is not a
threat. For example, it is probably acceptable for a person to be near a
toaster in the morning.

BUT, it is not advisable for a person to sleep under an electric
blanket, up close, live near a powerline/substation, and sleep in a room
where the power enters the home. This person is under an extreme case
of chronic exposure. This condition, unfortunately, applies to millions
of Americans.

If you wish to follows the EPA's advice and practice "prudent avoidance" then the following advice is offered:

Measure your home, work and school environments with a Gauss meter
Measure EMFs both inside and outside your home. Don't let your children
play near power lines, transformers, radar domes and microwave towers.

Avoid areas where the field is above 1 mG. Measure the EMFs from
appliances both when they are operating and when they are turned off.
Some appliances (like TVs) are still drawing current even when they are
off.

Don't sleep under an electric blanket or on a waterbed. If you insist
on using these, unplug them before going to bed (don't just turn it
off). Even though there is no magnetic field when they are turned off,
there may still be a high electric field.

Don't sit too close to your TV set. Distance yourself at least 6 feet
away. Use a Gauss meter to help you decide where it is safe to sit.

Rearrange your office and home area so that you are not exposed to
EMFs from the sides/backs of electric appliances and computers. In the
home, it is best that all major electrical appliances, such as
computers, TVs, refrigerators etc, be placed up against outside walls.
That way you are not creating an EMF field in the adjoining room.

Don't sit too close to your computer. Computer monitors vary greatly
in the strength of their EMFs, so you should check yours with a meter.
Don't stand close to your microwave oven. Move all electrical appliances
at least 6 feet from your bed. Eliminate wires running under your bed.
Eliminate dimmers and 3-way switches.

Be wary of cordless appliances such as electric toothbrushes and
razors. You may choose not to wear a quartz-analog watch because it
radiates pulsating EMFs along your acupuncture meridians.

An older mechanical windup watch would be an acceptable alternative.
It is also recommended to wear as little jewelry as possible and to take
it off at night. Many people have metal sensitivity which can be
aggravated by placing it right on the skin. Measure with a gauss meter
to be sure.

And last, but not least, always always always remember that EMFs pass
right through walls. The EMF you are reading on your Gauss meter could
be radiating from the next room...or from outside your home.



Additional Radiation Info:



Eyeglass frames should ideally be made from plastic with no wires in
them, otherwise they can serve as an antenna to focus the radio and
cellular phone waves directly into your brain.



What EMF Level Is Safe?



There's a heated debate as to what electromagnetic field (EMF) level
is considered safe. Since the experts have not come to an consensus,
you'll have to decide for yourself... Many government and utility
documents report the usual ambient level of 60-Hz magnetic field to be
0.5 mG.

Thus, any reading higher than 0.5 mG is above the "usual" ambient
exposure. Many experts and public officials, as well as the few
governments that have made an effort to offer public protection, have
adopted the 3 mG cutoff point. The EPA has proposed a safety standard of
1 mG. Sweden has set a maximum safety limit of 1 mG.

Dr. Robert Becker, an MD who has been studying the effects of EMFs
for 20 years, states a lmG safety limit in his book Cross Currents. When
electricians try to solve a magnetic field problem they do their best
to drop the level to 1 mG or below.

Dr. Nancy Wertheimer, a Ph.D. epidemiologist who has been studying
EMFs for 20 years, has been looking at the epidemiological data in a
different way -- she is trying to associate EMF levels with

health rather than disease. The level she is coming up with is a cut
off of 1 mG. Russian researchers claim that 1/1000ths of a mG should be
the standard.

The BioElectric Body believes that there are several stages of health
between "optimum wellness", "degenerative disease" and "Cancer". Thus,
we maintain our own living and sleeping quarters at 0.5mG and below.



Recommended Reading



Cross Currents The Perils of Electropollution. The Promise of
Electromedicine Robert 0. Becker, M.D. Jeremy P. Tarcher, Inc., 1990

Currents of Death The Attempt to Cover Up the Threat to Your Health Paul Brodeur Simon and Schuster, 1989

Electromagnetic Man Health & Hazard in the Electrical Environment
Cyril W. Smith & Simon Best St. Martin's Press. Inc. 1989


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