Summary of Oral Evidence presented to IEGMP by Mr L Wilson, Microshield Industries, on Friday 3 March 2000

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Mr Wilson introduced himself as managing director of Microshield Industries, a manufacturer of mobile phone shielding devices. He considered himself to be an expert on the issue of possible health effects of mobile phones. He explained that he had initially designed the Microshield for his own use and had subsequently patented the design in 1992. Microshield is actively involved in the issue, has helped to organise a conference, and raised funds for research, including £2000 for work by Dr de Pomerai. In addition, Microshield has paid for an assessment at the National Physical Laboratory (NPL), which had demonstrated that metal-rimmed spectacles increased absorption of radiofrequency radiation (RF) in the eye. Mr Wilson questioned why it was left to his company to fund this type of work. Asked about funding strategies, he replied that it is important to be objective, but that funding should be directed towards work that found effects rather than work that did not; he believes that the mobile telecommunications industry channelled funds in to "safe" areas of science that are unlikely to produce results damaging to their product.

People contacting Microshield had reported a number of symptoms. Whilst these had not initially been documented they had now compiled a database of symptoms reported by over 2000 people. However, he complained that he had been unable to find anyone who could make use of these data. Common symptoms included burning/heating sensations, numbness/tingling, and memory loss. A number of other symptoms including lymphomas and lumps were reported less frequently. Mr Wilson believes that mobile phones use could be responsible for an increased incidence of oral cancers and Non-Hodgkin’s lymphomas.

Mr Wilson presented the results of a MORI poll, which indicated that around 40% of phone users are concerned about possible health effects and that 62% of all users would consider purchasing a shielding device; this percentage was higher among more frequent users. He cited the view of the British Medical Association that 'consumers should be provided with information on radiation shields when purchasing mobile phones'. Quotes from other organisations related to the desirability of reducing unnecessary exposure and Mr Wilson believes that this could be achieved through the use of his product, but is concerned that information about shields was not widely available. He noted that the Carphone Warehouse now stocked Microshields as a result of a Money Programme item, but suggested that they promote hands-free kits in preference to his product. Mr Wilson indicated that British Telecom (BT) is now issuing concerned staff with hands-free kits. However, he noted that the use of a hands-free kit could result in high electric fields in the ear. Mr Wilson wants the National Radiological Protection Board (NRPB) to issue advice on shields. He accepts that NRPB cannot endorse specific products, but is concerned that in the absence of advice consumers might purchase devices such as the Techno AO that he believed were ineffective.

Mr Wilson indicated that NPL, Microwave Consultants, BT, and Assessment Services (now TUV) had tested the Microshield. Tests performed with phones emitting both high and low powers have indicated that the Microshield reduced exposures. The Group were concerned that as phones normally operate at the lowest power output consistent with high signal quality, adding a shield would simply cause both phone and base station to increase their emissions. Mr Wilson concurred that this is indeed what would happen, but that the aforementioned tests had all consistently demonstrated that the Microshield is able to cope with this additional surge, showing reductions in radiation absorption regardless of the power level at which the phone was operating. The test data indicate that emissions in the direction of the head are reduced by 90%, whilst those away from the head are reduced by 75%; results depend on orientation with respect to the base station. Mr Wilson also pointed out that the user’s head normally causes the phone to power up, referring to research that showed that the head causes a mismatch with the antenna and absorbs up to 80% of emissions. If phones can operate with a 75% attenuation of signal, the Group wondered why they do not just reduce their power output by the same amount. Mr Wilson explained that the reason is that the emissions left after the head has absorbed its normal quota would then probably be insufficient for the phone to operate. Mr Wilson explained that the Microshield is effectively taking the place of the user's head by causing a similar mismatch with the antenna, which tests show would selectively absorb radiation. If the Group wished to pose detailed questions, he was happy to supply written answers. Given the magnitude of the attenuation it is anticipated that battery life would be reduced, but Mr Wilson indicated that this effect was no greater than 8%.

Mr Wilson explained that the Microshield is constructed of a woven nickel-polyester material placed within a normal leather case. The transparent window is made of plastic containing a fine nickel mesh, and the slider on the antenna is made of plastic covered steel. The Microshield was initially designed for use with analogue phones in Hong Kong. This model had to be modified by the addition of a slider on the antenna in order to make it effective for use with digital phones. The Group could not see any reason why a case that is effective with analogue phones would require modification for use with digital phones. Mr Wilson suggested that a Faraday cage would block emissions from an analogue phone, but not from a digital. The Group suggested that the Microshield would not absorb emissions, just re-radiate them. Mr Wilson noted that measurements taken through 360 degrees had failed to detect re-radiated signals. He indicated that the RF is absorbed, although he could not say how the Microshield worked. He indicated that the slider on the antenna is used to prevent excessive signal degradation and suggested that it is possible to attenuate up to 90% of the signal with no loss of signal quality. With improved network coverage he believes that it would now be possible to use full shielding.

Following his presentation, Mr Wilson gave a practical demonstration of the Microshield.

First issued 10 May 2000