EMF Output Of Wireless Handhelds: Measuring The Data Love Experience

Why is it we can't stop ourselves from looking at celebrities? One look at the girl on the screen with the PDA on her head and we're deer in the headlights. It's the same sort of captivation that follows a car accident in the opposite lane, causing a mile-long "gapers block" on both sides of the highway. One more example pertinent to our subject: the popular "Blackberry" brand PDA is described as "addictive" by friends and relatives of dedicated owners. In other words, the world of technology is a psychology experiment and we are the rats. Interestingly, we came across a potential explanation for why, hypothetically speaking, the young male executive can't resist the urge to cradle his PDA upon his gonads, craning his neck toward it in the posture of an ancient one, or a female user, to balance the PDA on her gorgeous head. And that explanation, Dear PDA User (or Abuser) comes from a recent study of the electromagnetic output of several such devices, from which from inferences can be made as to why their extended use is not just behaviorally, but also physically addictive. A recent study of hand held wireless devices (Sage, Johansson, & Sage, Bioelectromagnetics, 2007) reported measurements of the extra-low electromagnetic frequencies emitted when PDAs are sending or receiving data streams. Peak emissions up to 975 milligauss were recorded. During email send and receive functions, the PDAs commonly had spikes of 30 to 60 milligauss. (Full abstract of the study is presented below the fold). Now we move on to human response to EMF exposure. When that heartthrob shows up at the party, and he or she is leaning up against the microwave while it's running and also thumbing away at a PDA, this may be a person with his or her brain's endogenous opioid system on full tilt boogey. (See second abstract below the fold for explanation) Something to consider in this circumstance: is it hug time or tin foil hat time? Exposure reduction options: keep the unit in "not transmit/receive mode" except to download and send emails, place the PDA several feet away at your work space or desk, and use as cell phone with an ear piece.

Note for abstract readers: 1 milligauss (mG) = 10 microtesla (mT)

Personal Digital Assistant (PDA) Cell Phone Units Produce Elevated Extremely-Low Frequency Electromagnetic Field Emissions

Cindy Sage,1* Olle Johansson,2 and S. Amy Sage1
1 1396 Danielson Road, Santa Barbara, California
2 The Experimental Dermatology Unit, Department of Neuroscience,
Karolinska Institute, Stockholm, Sweden

Initial tests indicate that personal and occupational use of personal digital assistants (PDAs or palm-held wireless units) produce high intensity bursts of extremely low frequency electromagnetic fields (ELF-EMF). These emissions could result in comparatively high ELF-EMF exposure in persons that carry a PDA close to the body (i.e., in a pocket or on a belt); or held to the head for cell phone conversations. ELF-EMF emissions of 10 uT were recorded on PDAs during normal office use over a 24 h test period. Results of ELF-EMF measurements show that email transmit and receive functions produce rapid, short-duration ELF-EMF spikes in the 2 — 10 uT range, each lasting several seconds to over a minute apparently depending on file download size. Some units produced spikes as high as 30 — 60 uT during email activities. Cell phone activity on PDAs produced continuously elevated ELF- EMF readings in the 0.5 — 1 uT range, as opposed to the rapid spiking pattern for email receipt and transmission. Switching the PDA unit from ''OFF'' to ''ON'' position resulted in single ELF-EMF pulses of over 90 uT on two units. Email downloads into the PDA can occur randomly throughout the day and night when the unit is ''ON''; thus the user who wears the PDA may be receiving high-intensity ELF-EMF pulses throughout the day and night. The frequency of email traffic on the PDA, and the power-switching unit (battery unit) may affect the frequency and intensity of ELF-EMF emissions. Bioelectromagnetics. 2007 Wiley-Liss, Inc.

Lai H, Horita A, Guy AW, Microwave irradiation affects radial-arm maze performance in the rat. Bioelectromagnetics 15(2):95-104, 1994
After 45 min of exposure to pulsed 2450 MHz microwaves (2 microseconds pulses, 500 pps, 1 mW/cm2, average whole body SAR 0.6 W/kg), rats showed retarded learning while performing in the radial-arm maze to obtain food rewards, indicating a deficit in spatial "working memory" function. This behavioral deficit was reversed by pretreatment before exposure with the cholinergic agonist physostigmine or the opiate antagonist naltrexone, whereas pretreatment with the peripheral opiate antagonist naloxone methiodide showed no reversal of effect. These data indicate that both cholinergic and endogenous opioid neurotransmitter systems in the brain are involved in the microwave-induced spatial memory deficit.

Image credit: http://www.rimarkable.com/archives/category/celebrity-blackberry-sightings/">Rimarkable


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