AegisGuardRadiation Shields
Cellular Phone Safety Questions Now Include Headsets April, 2001
An Overview of Health Implications for Cellular Telephone Usage, Particularly Among Young Adults and Children April, 2000
Cellular Phone Safety Questions Now Include Headsets
By: Matthew E. Brunnworth - Aegis Corporation
April, 2001


Note:   During January, 1998, Aegis was the first company to publicly address headset safety issues by informing its dealers and customers about the issues described in this White Paper.

In April, 2000, the British consumer magazine, Which?, reported that hands-free kits for cellular phones do not reduce the amount of radio frequency radiation being absorbed by the brain as many people believe. They claimed the wire leading from the phone acted like an antenna and increased the amount of radiation penetrating the head by more than 300% when compared with placing a cellular phone against the ear. Although their test methods were inconsistent with current regulatory test procedures, newspapers worldwide published their findings.

In July, 2000, and in response to the Which? report, the British government commissioned an independent laboratory, SARTest, to perform a series of SAR (Specific Absorption Rate) tests that are consistent with current regulatory test procedures used worldwide to measure and define the safety of cellular phones. The validity of SAR test procedures as the criteria for determining cellular phone safety is being debated globally.

Using these procedures, SARTests reported a reduction in the amount of radiation penetrating the head when using a headset of 90%. On the basis of this report, the British government reported that hands-free kits reduce phone radiation exposure and advised consumers to use them as safety devices. A similar report released by Australian scientists reported a reduction of 70%.

Overall, these findings revealed a 390% variance. 

Which? continued their investigations and commissioned another series of tests by the same laboratory that conducted their initial tests, ERA Technology LTD., in October, 2000, using five different phones and two different hands-free kits per phone. The test fixtures were presumably positioned in the way that most people would use a cellular phone and a hands-free kit: the phone positioned at or about waist level and the earpiece inserted in the ear with the wire hanging freely. First, measurements were taken with the phone handset next to the ear of a dummy head, and then taken again using a hands-free kit. During testing, the phones were moved up and down to vary the distance between the antenna mast and the earpiece. A follow up report released in November reported their findings that hands-free kits can reduce the amount of radiation penetrating the brain under a specific condition, however they can increase it by up to 350% under most conditions. They also reported why their findings were so different from SARTests and those of the government.

The critical factor
ERA’s laboratory took thousands of measurements to confirm the earlier test results and identify what was causing the differences. They stated the critical factor was that the wire of the hands-free kit served as an antenna and the distance between the phone’s antenna mast and the earpiece was a considerable factor for the amount of radiation traveling up the wire and emitted through the earpiece. At certain distances, there was a tuning effect that increased the electrical field at the headset’s earpiece.

The radiation levels for all 10 hands-free kits varied between distances of 40 and 80cm. There were two areas where the level of the signal at the ear was highest (from 40-47cm and again between 58-75cm), and one area where the level was lower (from 47-58cm). In positions where the levels were higher, they were between 46 - 259% higher than the phones themselves. In positions where the emissions were lower, the scale of the changes were between 8 - 97% for many positions of a phone and hands-free kit worn in normal use, the tests detected higher emissions from the kits than when the phones were held against the head. The testing did reveal that while hands-free kits can reduce the emission levels in one position, they also significantly increase in all others tested.

Exploring SAR
The premise behind SAR is that if body tissue heats up beyond a certain level, it can be dangerous. This is frequently referred to as thermal level and using this approach as the sole criteria for determining the safety of cellular phones and headsets has significant shortcomings. First, there is irrefutable evidence that phone radiation affects protective biological mechanisms in the body far below what can be measured at the thermal level. Second, SAR does not consider long-term biological effects, but only observable behavioral effects induced in laboratory animals for the brief amount of time a phone or headset is tested. But perhaps the greatest testament that SAR standards should not be used is that none of the health disorders attributed to cellular phone radiation are thermally induced and all of them have a long incubation period. 

SAR tests are based upon a calculated amount of energy that can safely be absorbed by the body, measuring energy in watts per kilogram that one gram of body tissue absorbs. It is calculated by measuring the maximum radio signal level inside the head and applying this value to a formula to calculate a SAR. 

Tests are performed by inserting an electric-field test probe into a dummy head filled with a gel-like liquid that simulates the same electrical proprieties as brain tissue. In this case, it measures how much the brain heats up when a cellular phone is placed against the head and when a hands-free kit is used. Although in the process of being standardized as the method for rating radio frequency radiation from cellular phones, it is widely debated because it measures brain temperature increases after exposure for a brief amount of time and not actual radiation emissions. This is one of the primary reasons why AegisGuard™ Radiation Shields were tested using ASTM test procedures instead of SAR. 

Some scientists have concluded SAR levels are not the critical consideration because the radio frequency can be a far more damaging element than the amount of radiation absorbed. For example, a group of Spanish researchers released a report in late 1999 stating this method of calculating cellular phone emissions substantially underestimates their effects on human tissue.

SAR hands-free kit test limitations
To find out why the SAR tests showed hands-free kits reducing radiation levels being absorbed, Which? also employed the services of SARTests. Although the test procedures were similar to those used by ERA, they found differences in the way they were applied to testing hands-free kits. One consideration was the dummy head used at ERA’s facilities had an outer ear to accurately maintain a relative position for the phones and the hands-free kits; the test head at SARTest did not. An important difference was the SAR test fixture was on a wide platform that did not position the hands-free kit in the position most people would normally use. In fact, SAR measurements were taken with the phone lying on the platform, basically at shoulder height, with the wire coiled around or alongside of it. During testing, the wire was moved as much as possible and significantly increased SAR levels measured at the ear from the hands-free kits.

The most significant difference is that with the SAR test system, the probe scans the entire inside cavity of the dummy head and only provides a measurement for the area where the highest radiation level appears. With the kits, the highest emissions were at the ear; with the phones, it was at the jaw and cheek. ERA tested the phone and the hands-free kit earpiece at the same location, inside the head at ear level. Unlike ERA’s test, the SAR test system does not provide a reading for radiation emissions at the ear (close to the brain) for phones, only inside the dummy head.

Handle with care
Cellular phone radio waves are non-ionizing radiation. At high levels, such as those found in radar and microwave ovens, they can heat and severely damage living tissue. Similar to principle of mounting television antennas on rooftops, a phone transmits and receives better signals from head height than at waist level. According to phone manufacturers, hands-free equipment was designed for convenience, such as allowing writing or typing while listening to the phone and to reduce the possibility of accidents while driving. They were not designed to reduce radiation emissions.

The controversial issue is whether cellular phone radiation is dangerous to your health, and does the use of a hands-free kit increase or decrease that risk. Most people will attach the phone at the waist and connect a headset to it, causing the phone to increase it’s output power, which is an important consideration. This raises concern for unprotected body tissue at the waist level, such as the liver and kidneys, which have excellent conductivity and absorb radiation faster than the head due to a lack of surrounding bone. When a hands-free kit is attached to a cellular phone, electrical currents are conducted and induced on the wire, exposing internal organs and channeling the radiation more effectively through the ear piece.

What scientists know
For years, electromagnetic radiation has been suspected of causing a wide range of disorders, ranging from dizziness to genetic damage. Opinions differ between researchers on the effects of radio frequency radiation because of non-standardized testing procedures and materials. Traditionally, they have been separated into two categories: thermal (high energy) and non-thermal (low energy). Scientists understand the brain heats up when using a cellular phone, but the actual long-term biological effects of radio frequency radiation haven’t been determined, and they will not be determined for quite some time. Researchers worldwide are investigating non-thermal radiation to discover if there are ill-health effects, and there have been studies confirming effects upon the body far below what can be measured at the thermal level.

Medical researcher Dr. Bruce Hocking claims that cellular phones are likely to disturb nerve functions.  He has reported a marked difference in the responsiveness of nerves behind, and just in front of, the ear after using of a cellular phone.

Swedish medical investigators conducted a two year study of patients with brain tumors.  They concluded that cellular phone users of analog phones (the kind most commonly found in the U.S.) are at an increased risk of developing brain tumors, which are most likely to appear on the side of the head where users hold their phones. Unlike analog phones however, digital phones use pulsed transmissions that some scientists believe are more dangerous.

Cellular phones may present a danger even when they are not in use.  Dr. Roger Coghill, a British biologist, found that cellular phones on standby mode lowered the white blood cells to 10% of normal activity after exposure to radio frequency radiation.

A team of researchers in Spain claim the effects of cellular phone radiation could be 20% higher than previously thought.  By studying more realistically shaped computer models of cells, they discovered electric fields are amplified across the cell membrane, a factor that had not been considered in other studies.  It was also found that the angle of the cell in relation to the source of radiation is important, and that interactions between neighboring cells can significantly modify the electric field within each cell.

Researchers have discovered that electromagnetic radiation can cause subtle, short-term biological effects, including changes in brain wave patterns during sleep.  Although cancer studies have so far been inconclusive, organizations including the National Cancer Institute and World Health Organization are investigating the issue. Many experts caution it’s too early to give cellular phones a clean bill of health, and it is important to understand that cancers represent a small number of the heath effects attributed to cellular phone radiation.

Change of heart
In December 2000, the British government reversed their endorsement advising consumers to use hands-free kits as a safety device that reduces cellular phone radiation exposure to the brain. The government sent out leaflets stating, “…The effectiveness of hands-free kits is uncertain”, and requested its citizen’s take a precautionary approach to cellular phones, particularly with children.

FDA position
In May, 1995 and again in February, 2000, the FDA made no commitments concerning the effects of electromagnetic radio frequency radiation by saying “There is currently insufficient scientific basis for concluding either that wireless communication technologies are safe, or that they pose a risk to millions of users”.

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An Overview of Health Implications for Cellular Telephone Usage, Particularly Among Young Adults and Children
By: Katherine Krebs - Aegis Corporation
April, 2000

As an industry, wireless communications is matched only by the personal computer for the rate in which new products are being introduced in the marketplace. Once a novelty item, cellular phones have become as commonplace as the PC among both adults and children. As of March 31, 2000, cellular telephones were used by more than 86 million Americans.

The percentage of teenagers using cellular phones rose from 15% to 35% in 1999, and is projected to reach 70% by 2002. Without question, the cellular phone has become the accessory of choice among young adults, outselling PlayStations, TV's, and even personal computers. Teenagers regularly place calls from the mall to the classroom, use sophisticated phones to "surf the net" or check their e-mail, and chat with friends.

However, technology does not evolve without consequences. A worldwide debate has ensued among scientists, regulatory agencies, and phone manufacturers over the health implications resulting from cellular phone usage. It should be noted that phone manufacturers and most regulatory agencies insist there are no health risks associated with the use of cellular phones.

Executive Summary
As the new status symbol becomes status quo, cellular phone health considerations must continue to be investigated and reported to the public in a timely manner. One of the most significant research challenges is that cellular phones and wireless technologies are evolving faster than laboratory testing can be completed.

Though it has been difficult to find a conclusive link between cellular phone radiation and the effects among children, studies conducted have underscored the need for more research into the potential health risks, which point to greater biological damage for young children.

This document was created to provide recent information about the potential health risks from cellular phone usage, including excerpts from published studies and comments from leading scientists in the field.

To simplify the language in this report, the familiar phrase "cellular phone" is used, rather than a generic identifier such as "wireless communications device." The conclusions of this report are in no way intended to prove or disprove that wireless communication technology is safe or unsafe.

The cellular industry acknowledges that cellular phone radiation penetrates the head and neck of the user when a phone is in use, thus increasing the temperature (thermal level) of the brain and surrounding facial areas. Studies conducted in 1999 confirmed the radiation also affects protective biological mechanisms in the body far below what can be measured at the thermal level.

Background studies have found:

Up to 60 per cent of the radiation emitted by a cellular phone is absorbed by the user's head.

The radio system (transmitter and receiver) and internal antenna body installed along the length of the handset generate the highest emissions.

Radio frequencies used by cellular phones have been shown to effect changes on a cellular level and alter DNA.

A higher than average risk of contracting cancers of affected organs (most notably the brain) as well as other diseases such as Alzheimer's and Parkinson's.

Some scientists are conducting studies to determine if cellular phone usage has a greater impact on children than adults. Dr. Gerard Hyland, a physicist from the University of Warwick, is regarded as an expert in the field and among those who believe that cell phones could potentially be very dangerous for young children.

Dr. Hyland is a specialist in the effect of low intensity radiation and said: "The problem is the electromagnetic emissions which come out in bursts from the body of a mobile phone. There is a certain frequency pattern in the emission that the brain happens to recognize. In children below the age of 12, the stability of the brain could be undermined and disrupted because their brain is in a more vulnerable state."

Hyland warns that the radiation from cellular phones could also affect chemical activity in the brain. Said Hyland: "The blood brain barrier which keeps infections out of the brain could be made more permeable and that could increase the risk of infection."

He warns that the radiation from cellular phones could also affect chemical activity in the brain.

The Brain Barrier
In a recent study led by Dr Mika Koivisto of the University of Turku, results suggested that exposure to the electromagnetic field emitted by cellular phones may have a facilitatory effect on brain functioning, especially in tasks requiring attention and manipulation of information in working memory.

In the study, a team of 48 volunteers aged 18 to 49 were asked to complete a set of 12 tasks which tested a range of functions including reaction times, memory, accuracy and mental arithmetic. All volunteers were asked to carry out the same tasks during two sessions 24 hours apart.

During both sessions, volunteers wore a phone mounted on a headset in the normal position with the antenna 4 centimeters (1.5 inches) from their heads. They were unable to tell whether or not the phones, controlled by a remote computer, were switched on or off. The Bristol study found decreased reaction times only in simple choice tests when users were exposed to old-style analogue phones, not digital handsets.

Dr Alan Preece, who led the Bristol study, said: "This research basically confirms our findings. What we still don't know is what mechanism is causing these effects. There are three or four possible mechanisms which need evaluating before we can say what the long-term effects will be." In the next studies, scientists will consider whether radiation dilates the blood vessels feeding more oxygen to the brain, a mechanism linked to heating which is thought unlikely to cause long-term damage.

What is the FDA's Position?
In February, 2000, the FDA issued a Nomination stating "There is currently insufficient scientific basis for concluding either that wireless communication technologies are safe or that they pose a risk to millions of users."

AegisGuard™ Radiation Shields: Your Partner for Precautionary Protection
Aegis Corporation introduced a shielding technology in 1998 which deflects up to 99.9% of the radiation emitted by cellular phones away from the head and neck of the user without affecting reception or battery life.

Cellular phones emit the same form of electromagnetic radiation produced by microwave ovens, and all microwave oven doors have embedded shielding material that deflects the radiation back into the cavity of the oven. Aegis engineers developed AegisGuard™ Phone Radiation Shields, a product family proven to deflect, rather than absorb, the radiation emitted from cellular phones and other wireless products (NOTE: This product was replaced by AegisGuard™ LS Radiation Shields in 2005).

"This is a significant distinction because a shielding product using absorption materials loses its effectiveness as it becomes saturated, exposing the user to radiation," said an Aegis spokesperson in an April, 2000 press release.

This distinction was confirmed by Dr. Neil Cherry, a biophysicist from Lincoln University and another expert in the field. During a radio interview in New Zealand on February 6, 2000, he said, "A (specific type of) fine metal mesh can provide significant shielding from UHF and microwave radiation. That is why microwave ovens have a reflective (deflective) metal grill over the glass door. If the holes are much smaller than the wavelength of the radiation, it is a good shield. The shield must work reflection (deflection) to avoid saturation."

Of all the studies conducted around the globe, it is fair to say that various test procedures and protocols yield differing results worldwide. But the facts remain. Radiation emitted from cellular phones pose a potential health risk to the adults, and especially the children, of our nation.

What, then, can we do to limit our exposure to cellular phone radiation?

Shielding the phone is the ideal solution for deflecting radiation away from the head and neck.

Limit your exposure, or your family's exposure, by using them less frequently and for shorter periods of time.

A portable hands-free plug-in device will only move the area of greatest exposure from your head to wherever you wear your phone, be it your belt, jacket pocket or elsewhere.

Consumer education programs need to be put in place. Educational materials should be developed and disseminated to educate the public about the potential health risks associated with cellular phone usage. These materials would inform people of the subtle influences of cellular phone use (e.g., thermal and radiation studies). They could illustrate how cellular technology emits radiation, include articles on the blood/brain barrier, and provide information about how to protect themselves.

We hope that organizations and individuals worldwide take a particular interest in this issue. In addition, we hope it presents a call to action for further advocacy efforts surrounding this timely issue.

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