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Michael McIvor, medical director of the Research Center at the Heart Institute of St. Petersburg, Florida, claims that prolonged exposure to signals emitted from some theft detectors, caused by standing in the reader portals, could cause dizziness or fainting in pacemaker wearers.
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A controversial study of retail security systems' impact on people with pacemakers, condemned twice in previous years, has come back to life as the study's author pressed his case recently in Europe.
According to the St. Petersburg, Fla., heart specialist, people with pacemakers should proceed at a quick pace through antishoplifting devices. Dr. Michael McIvor, medical director of the Research Center at the Heart Institute of St. Petersburg, Fla., claims that prolonged exposure to signals emitted from some theft detectors, caused by standing in the reader portals, could cause dizziness or fainting in pacemaker wearers.
In addressing the Center for Retail Research, McIvor claimed, "if you walk through the device and you don't stop, you're probably not going to be hurt. But if you stand in the device, there is a potential for harm." Dr. McIvor was not available for comment by SECURITY Magazine.
But, as in previous coverage of McIvor's claims, critics have pelted the Florida doctor's research and report conclusions
Some accuse McIvor of grossly exaggerating the results. Dizziness and fainting, for example, were only reported in four cases of pacemaker wearers exposed to anti-shoplifting signals.
McIvor admitted that the risks are small, but feedback following media coverage of the unpublished study argued that the risks are not as much small as infinitesimal.
Following the latest news of the McIvor study, another cardiologist, in the largest study of its kind, confirmed that anti-shoplifting systems are safe for people who wear pacemakers.
Dr. Jacques Mugica tested the effects of electronic article surveillance (EAS) systems on 178 pacemaker wearers. The results were published in the French medical journal Stimucoeur: "Our experience shows clearly no danger related to EAS systems. [The study's] conclusion is also supported by the follow-up of thousands of patients with pacemakers. We should, therefore, be responsible in avoiding exaggeration regarding these systems, which have been proven safe," Mugica says.
EAS Effects Harmful?
Another earlier study cited by EAS maker Sensormatic Electronics, Boca Raton, Fla., also found "that there is no danger at all for pacemaker patients walking through anti-theft systems at their own ordinary pace."
But what about standing for a period of time in range of signals emitted by EAS devices?
The Mugica study found that pacemakers were effected by prolonged exposure to EAS signals, but these effects were controlled by the pacemaker.
Powerful electromagnetic fields admittedly have the potential to alter pacemaker functions because they generate electromagnetic interference (EMI). Some EAS systems are acusto-magnetic-based while others are electro-magnetic- or radio frequency-based. A strong field could cause miscommunication between the pacemaker and the person's heart.
Yet according to Medtronic, the Minneapolis, Minn., medical technology company specializing in implantable, invasive and interventional therapies, "there are several safeguards to shield [pacemakers] from electromagnetic interference - [including] electronic filters that differentiate between natural heartbeat signals and EMI signals, as well as the metal housing that surrounds and shields the pacemaker's battery and circuitry."
Medtronic's advice is to walk normally through EAS security devices, and if the wearer suspects interference with the pacemaker, "simply move away from the device."
The pacemaker reportedly suffers no permanent effects and will resume normal operation.
Copyright Cahners Magazine Division of Reed Publishing USA May 1998