THEORIES ON HOW EMF AFFECTS BIOLOGICAL SYSTEMS

For many years some scientists and engineers felt that low frequency EMF could not possibly produce significant biological changes or effects. This reasoning was based upon the fact that low frequency EMF cannot break molecular bonds and it generates only a miniscule amount of heat - not enough to heat body tissue. However, this argument has turned out to be incorrect because there are other ways in which fields can interact with individual cells to produce biological changes.

If we recall that magnetic fields can induce an electric current in a nearby conductor, the implication is that AC magnetic fields will induce electric currents in our bodies (although such currents will be very small). That's because our bodies are mostly comprised of a conductive medium (salty water). Some of these currents are similar to what a salamander uses to regenerate a limb, and therefore the artificial creation of these currents in a human body are of concern.

The way in which electromagnetic radiation affects the body is not fully known. A similar state of knowledge applies to the mechanisms behind how aspirin cures a headache or reduces fever, or why asbestos causes cancer. One theory is that EMF causes the cell walls to vibrate, or to resonate, in the same way you can shake a bowl of jello and observe it oscillate back and forth at a certain frequency.

Resonance is not necessarily harmful. The body is composed of many elements that can resonate at different frequencies. The human ear is an example of a part of the body which resonates in tune with its environment. When we listen to the music of a violin, we are hearing a sound vibration of 5,000 cycles per second. The sound from a violin is transmitted by pressure waves in the air, not magnetic radiation. We know that the human body has no difficulty dealing with this kind of sound-induced resonance (unless, of course, the amplitude is very large, as with the sound of a jet engine).

In the case of EMF, resonance with cells occurs when there is a "match" between the wavelength of the radiation and the physical size of the cell. The resonance maximizes the transfer of energy into the cell, and can result in observable biological effects which may be harmful. One observable effect is a disruption in the calcium flow through cell walls. Calcium acts as a messenger that penetrates into the cell, conveying important information and triggering proteins to carry out cell functions. Calcium also plays an important role in regulating certain body functions, such as muscle contractions, heartbeat, development of egg cells and cell division. Since cancer growth depends on cell proliferation, these findings seem to explain why EMF sometimes behaves like agents that pro mote, rather than initiate, cancerous growths.

Another theory is that the altered calcium flow to the cell reduces the cell's ability to fight cancer. According to Craig Byus, a biochemist at the University of California at Riverside, just because the fields are very small doesn't mean they are innocuous. Cell membranes appear to have a way of amplifying the fields. Due to the poor conductivity of the thin cell wall, small induced currents produce large voltage potentials across the cell membranes, disrupting the chemical balance.

Are weaker fields safer than stronger ones? Logically, our experience with other pollutants would lead us to answer yes, but scientists say this may not be the case because there are "windows" or ranges of biologically active frequencies and field strength. Some experiments show no effect with a strong field, but when the field strength is reduced an effect appears. Other experiments show that above a certain field strength, effects can be observed but no additional effects occur when the field strength is increased.

The resonance effect between EMF and the surfaces of cells may help explain the strange window effect. To understand why, an analogy may be made with the noisy shaking of water pipes sometimes observed when running water from a faucet. As the faucet is opened, a small flow presents no problem. Then, as the initial low flow is increased, a loud noise may occur due to pipe resonance. When the flow is increased even further, the effect doesn't get worse, and usually it stops.

The shape of the magnetic pulse also seems to play a role, too, as different pulse shapes cause different effects. The strength of a 60 Hz EMF field from power lines and household wiring increases and decreases smoothly, while the VLF field from a VDT has a saw-tooth pattern. All this complicated evidence makes it difficult to reach any conclusions on what level of EMF exposure is safe and what isn't. The consensus is that more research is needed.

In a 1991 study conducted by the Electrical Systems Division of the Electric Power Research Institute, researchers found that magnetic fields produced by underground cables vary by as much as 10 to 1, depending on the method of installation and cable construction. According to the study, a person standing directly over an underground cable with the worst configuration (from an EMF perspective) will be exposed to the same level of EMF as a person standing at the edge of the right-of-way for an overhead transmission line. Unfortunately, the study also found that the best configurations for the lowest EMF are less efficient for electric power transmission.

With concern about EMF in mind, new and different underground cable systems are being developed. The lowest field underground design has three insulated cables lying adjacent to each other in an oil-filled pipe that cools the cables. This configuration can result in magnetic fields 1/10 to 1/20 of the equivalent overhead line. The EMF can be reduced even further, sometimes to near ambient background levels, if the pipe is grounded in a special way.

HEALTH CONCERNS RELATING TO CRT-STYLE VDTs

Other studies concerning the effects of EMF on embryos show reason for concern. According to Dr. Ezra Berman of the Environmental Protection Agency, "the Henhouse Study [of chicken embryos exposed to low frequency magnetic fields] performed in four countries has contributed significantly to the growing database implicating an association of [EMF with an] increase of abnormalities in chick embryos." Expert Louis Slesin, publisher of VDT News, says "the new results should help convince skeptics that magnetic fields can be biologically active at very low levels."

However, pregnant women and their unborn fetuses are not the only ones at risk. CRT-style VDTs can emit levels of ELF magnetic radiation which is far higher than 2 to 3 mG (the level associated with higher risks of brain tumors, leukemia and other cancers). Consider the fact that the vast majority of VDT operators in the U.S. are women and that the incidence of female breast cancer has been rising steadily along with VDT use. Breast cancer now accounts for 29% of all cancers among women, and an astounding 1 out of 9 women will contract the disease.

Because of the relatively short period of time computers have been used, more studies are needed before there is conclusive evidence regarding adverse long-term effects. However, with the extremely strong evidence that ELF magnetic radiation increases the incidence of leukemia and brain cancer, some experts fear that long-term VDT use will also be shown to increase the likelihood of contracting cancer, and/or inhibit the ability of the computer operator to fight off cancer that might otherwise be held in check or destroyed by the body's immune system. Remember that power lines have been around for one hundred years and the cancer link is just now being established. It took over 40 years of research to conclusively establish the dangers of smoking. VDTs have only been widely used for the past twenty years.

Other less severe problems sometimes associated with VDTs are headaches, fatigue, nausea, dizziness, irritability, skin redness or rashes, and eye strain.

NON-CRT DISPLAYS

LCDs (liquid crystal displays) are commonly used in portable laptop and notebook computers. Many experts consider LCDs safe, believing that they have lower EMF levels. Since LCDs are backlit or sidelit with fluorescent lights, they emit magnetic fields in the ELF and VLF range. The strength of the ELF and VLF magnetic fields coming from an LCD vary greatly, depending upon the manufacturer. Although LCD magnetic fields are less than those produced by CRT-style VDTs at comparable distances, at 6 inches some laptops emit up to 22 mG of ELF magnetic fields, and 2 mG of VLF fields and that far exceeds the levels set under the Swedish MPR 2 guidelines at 20 inches. This is significant because a laptop may actually be placed on a person's lap.

TELEVISIONS

TVs emit the same assortment of radiation as computer displays, since both devices incorporate a cathode ray tube (CRT). Fortunately, a viewer doesn't have to sit right next to a television set to still see the image. Sitting ten feet away from a 19 inch TV distances the viewer from any measurable ELF or VLF fields. Some televisions, though, are particularly strong, so it makes sense to test your TV with a Gauss meter. A Gauss meter is also useful when buying a TV, since sets can vary quite a bit from one another.

Many appliances generate AC electric and AC magnetic fields, even when they are turned off. For example, televisions with remote controls still have current flowing when not in use. This current generates EMF, although it is less than when the TV is in use. Radios, too, may produce EMF even when turned off.

If you need to watch TV in a confined space, you should consider purchasing a small LCD TV. They have quite a strong electric field at 1 inch, but at the distance of 1 foot, the magnetic fields are negligible.

ELECTRIC BLANKETS

Electric blankets create an AC magnetic field that penetrates about 6 or 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.

In response to EMF concerns, the major U.S. electric blanket manufacturers: Fieldcrest, Casco-Belton and Northern Electric (Sunbeam) have come out with "zero magnetic field" blankets. In one design the wires are laid out in pairs so that the magnetic fields are balanced. Another design uses DC electricity, which doesn't emit pulsed EMF. Although these models reduce or eliminate magnetic fields, the blanket may still produce electric fields, even when turned off. This is because current does not have to be flowing for an electric field to exist. If the on/off switch cuts the neutral wire instead of the hot wire, the user would then be subjected to the electric field coming from the hot wire in the blanket. That's why it is best to use an electric blanket only to warm your bed before you get in it. Once you're in bed, the blanket should be unplugged to be absolutely safe. This advice is especially valid for children and pregnant women.

Waterbeds should be warmed during the day, but unplugged before going to bed. However, an unheated water bed can get quite chilly, so you may need a thick mattress pad or quilt to stay warm. Use of heating pads for chronic problems should be discontinued and replaced with hot water bottles.

ELECTRIC CLOCKS

A dial-face (analog) electric clock has a very high AC magnetic field, as much as 5 to 10 mG up to two feet away. If you are using a bedside plug-in dial-face alarm clock, it should not be placed near your head. Studies have linked high rates of brain tumors with chronic exposure to magnetic fields, so it is wise to place all plug-in clocks and other electric appliances at least 5 feet from your bed. Better yet, you may want to use a battery-powered alarm clock. Some travel clocks feature snooze, a digital display and even a radio alarm, yet they work on batteries so they have a negligible magnetic field.

FLUORESCENT LIGHTS

Fluorescent lights have replaced incandescent lights in most offices and schools. Fluorescent lights are cooler, last longer and consume less electricity, so they are more economical to use. A fluorescent bulb has no filament. Instead, the bulb is coated on the inside with a fluorescent material called a phosphor. The bulb is also filled with argon gas and mercury vapor, and a transformer (called a ballast) is used to increase the voltage to the electrodes on each end of the bulb. The high voltage excites electrons in the gas, which give off ultraviolet light. When the ultraviolet light strikes the phosphor coating on the bulb, the phosphor emits visible light which passes through the glass.

Fluorescent lights produce much more EMF than incandescent bulbs. At a distance of two inches from an incandescent bulb, the ELF field is .3 mG, and at six inches it is barely measurable. On the other hand, a typical fluorescent lamp of the type commonly found in office ceilings can have a reading of 160 to 200 mG 1 inch away. At 6 inches the reading drops to 45 mG, at 12 inches the reading is 14 mG , at 24 inches the level is 1.7 mG, and at 30 inches the level is close to background. Thus rooms with low ceilings and fluorescent lights may have readings above 2 mG at head level. In multi-story schools with fluorescent lights, although young children may be far enough away from the ceiling fixtures, they may still be exposed to EMF from the lights on the floor below.

MICROWAVE OVENS

Microwave ovens are interesting because they emit two types of radiation: microwave and ELF. The microwave radiation, which is very high in frequency (in the billion Hertz range), is produced by an element called a magnetron. Microwaves make water molecules vibrate. It is this vibration that creates the heating process, and stray microwaves can cause serious health problems by heating body tissue. Current regulations require that a microwave oven leak no more than 1 milliwatt per square centimeter when it leaves the factory. We have no idea if this level is safe, and one study has indicated that the level should be less than .5 milliwatt per square centimeter. Since microwave emissions can change with normal use, it is best to have a qualified repairman check your oven each year.

Microwave ovens also create a 60 Hz EMF field because they have a strong power transformer. The 60 Hz component of a microwave oven usually travels five feet, so it is recommended that you stay at least five feet away from a microwave oven while it is in operation.

TELEPHONES

Telephones can emit surprisingly strong EMF, especially from the handset. This is a problem because we hold the phone so close to our heads. Measuring different telephones before you buy is important because the field strength can vary a great deal in just a matter of inches. Place a Gauss meter right against the ear piece and the mouth piece. There are several telephone handsets in the market with no measurable fields, while others emit a relatively strong field that travels several inches. That's the same distance from your ear to your brain!

As with most small appliances, the body of the telephone has a magnetic field that extends one or two feet. Because of this it is a good practice to position the phone as far as possible from the user.

ELECTRIC RAZORS AND HAIR DRYERS

An electric razor which plugs into the wall produces an extremely high-strength AC magnetic field, as high as 200 to 400 mG one-half inch away from the cutting edge. This seems alarming, but we don't know if this is worse (or better) than exposure to a 2 to 3 mG field (the level linked to increased risk of cancer). If exposure to such high fields is a problem, the duration of the exposure (the dose-rate concept) might mitigate the effects. To understand the dose-rate concept, consider that we can zip a finger through the flame of a match without burning ourselves. This is evidence that short-term exposure to certain harmful influences can produce dramatically different results than longer exposure. If the dose-rate concept applies to EMF (and we don't know if it does), since an electric razor is used only a few minutes each day, it is probably safe. Keep in mind, however, that the data on short-term exposure to high-strength fields is incomplete, and that the use of non-electric razor blades will eliminate all EMF risks. There are now wind up mechanical razors available, which use a non electrical flywheel for power. A small epidemiological study found a link between electric razor use and higher skin cancer in men. Presumably the fields, being close to the brain, could influence production of melatonin, a cancer fighting hormone. Also, recent reports are pointing to the fact that cells go through the most disturbance at the beginning of field exposure, and later try to compensate. As such, non electrical razors are recommended.

Electric hair dryers are another source of extremely high AC magnetic fields because they require high currents to produce heat. A 1600-watt model will produce 100 to 200 mG near the handle and 10 to 50 mG at normal drying distances (6 to 18 inches). When it is operated on its "high heat" setting, it will draw more current and generate a higher magnetic field than when it is operated on its "low heat" setting. Again, in evaluating the health risks, the dose-rate concept may provide comfort, since a hair dryer is used only a few minutes each day. On the other hand, hairdressers who use a hand-held hair dryer repeatedly each workday may have something to worry about.

PRUDENT AVOIDANCE

Electricity is an inseparable part of our modern day society. This means that electromagnetic radiation will continue to be all around us for the foreseeable future. But, as Discover Magazine postulated, aside from making our lives easier, is electricity also making our lives shorter? Perhaps a more important question is "Until more is known, what can we do to minimize the potential risks?"

Prof. M. Granger Morgan, a well-known expert at Carnegie Mellon University, says it certainly can't hurt to take simple steps. EMF "may pose no risk," he says, "but most experts I have talked with give me odds somewhere between 10 percent and 60 percent that within the next decade it will become clear that they do." Prof. Morgan advocates "prudent avoidance." "Prudence" means to be sensible and to exercise sound judgment in practical matters. Hence, prudent avoidance means that we should avoid exposure to EMF when it is consistent with sound judgment. In other words, learn where EMF comes from and then distance oneself from it whenever such avoidance won't cause too much personal or economic disruption.

Most experts agree that limited, non-chronic exposure to EMF is not a threat. For example, it is probably acceptable to be near a toaster in the morning, but it is not advisable to sleep under an electric blanket operating all night. Certainly the person who works on a computer all day, watches TV close up at night, lives near a power line, and sleeps under an electric blanket, is under an extreme case of chronic exposure. This condition applies to millions of Americans and people throughout the world.

If you wish to practice prudent avoidance, the following advice is offered:

• Measure your environment with a Gauss meter, and avoid areas where the field is above 1 mG. Measure the fields both inside and outside your home, and don't let your children play near power lines, transformers and microwave towers.
• Measure the magnetic fields from appliances, both when they are operating and when the are turned off. Magnetic fields are created only when current is flowing, but some appliances (such as TVs) are still drawing current even when they are switched off.
• Don't sleep under an electric blanket or on a water bed. If you want to warm your bed before go to sleep, when you're ready to get under the cover, unplug the electric blanket (don't just turn it off). Even though there is no magnetic field when the blanket is 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, but keep in mind that EMF from some TV sets can be measured as far away as 10 feet or more. An ELF and VLF Gauss meter can help you decide where to sit.
• Don't sit too close to your computer display. Keep at least an arm's length away from the screen, but remember that at this distance you will still be within the magnetic field. Computer monitors vary greatly in the strength of the magnetic fields which they emit.
• Rearrange your office work area so that you and your co-workers are not exposed to EMF from the sides and backs of each other's VDTs.
• Turn off your VDT when you are not using it.
• Consider purchasing a low radiation VDT which contains an active compensating coil, or a zero radiation display based on shielded LCD technology.
• Don't stand close to your microwave oven when in use. Even if your microwave oven is not leaking microwaves, it will still give off strong ELF magnetic fields.
• Move your electric clock away from your pillow. Several feet away should be sufficient. Better yet, buy a battery-powered digital clock.
• Keep other electric appliances away from your pillow, too. Telephones and answering machines generate EMF.
• Eliminate dimmers and three-way switches; they create high fields.
• Eliminate wires running under your bed.
• Be wary of cordless appliances such as electric toothbrushes, which use magnetic induction to charge the battery. Such devices deliberately create a large magnetic field.
• Remember that EMF passes right through walls, so check out what's on the other side. It could be a cordless electric toothbrush, or a television set, or a clock-thermostat radiating EMF into your bedroom.

A final note on AC fields: just like medicines have good and bad effects, not all AC electric and magnetic fields are negative influences. Under controlled circumstances, AC fields can be used to help our health. Some AC magnetic fields, for example, are used at hospitals to promote bone growth in the case of fractures. Similarly, Magnetic Resonance Imaging (MRI) machines are very useful in detecting tumors, aneurysms, etc., and are an excellent alternative to X Rays or CAT Scans. Other devices that use AC magnetic fields are also in use, such as AC Tens units to treat pain, as well as other magnetic devices that treat other symptoms and complaints. Static magnets have now been reported in the medical literature as being benefitial for diabetic neuropathy, (tingling and chronic pain in the feet), a condition affecting half of all diabetics, or almost 10 million people. Static magents have also been shown to be effective in many pain complaints.

About Technology Alternatives Corporation

Technology Alternatives Corporation, located in Miami, FL, has been a pioneer in the area of prudent avoidance of EMF. Technology Alternatives manufactures a zero radiation LCD computer display and several models of hand-held, inexpensive Gauss meters for measuring magnetic radiation from power lines, home wiring, appliances, televisions, and computer displays. Technology Alternatives also markets ultra-low radiation CRT-style video displays, and offers a radiation reduction service for retrofitting selected models of existing CRT-style VDTs.

Technology Alternatives Corporation has received worldwide acclaim for its innovative products. The company has been featured or mentioned by the following news sources: The Boston Globe, the Chicago Sun Times, The Washington Post, Business Week, MIS Week, The Boston Business Journal, UPI, NBC radio, WXEX in Richmond, Virginia, Channel 6 in Providence, RI, Good Morning America, USA Tonight, Channel 7, an ABC affiliate in New York, Glamour Magazine, PC Week Magazine, Lotus Magazine, Compuserve Magazine ("Averting Desktop Cherno-byl"), Adweek's Computer Magazine (Cover story: "Are VDT's Safe?"), Marketing Computers Magazine (Cover story: "Caught in the Crossfire"), PBS TV, WAGA Atlanta TV (a CBS affiliate), Channel 4 WNBC NY TV, and CNN Business News.

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