Bioelectromagnetics (2007) Personal Digital Assistant (PDA) Cell Phone Units Produce Elevated Extremely-Low Frequency Electromagnetic Field Emissions

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 mTwere 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 mT range, each lasting several seconds to over a minute apparently depending on file download size. Some units produced spikes as high as 30–60 mT during email activities. Cell phone activity on PDAs produced continuously elevated ELF-EMF readings in the 0.5–1 mT 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 mTon two units. Email downloads into the PDA can occur randomly throughout the day and nightwhen the unit is ‘‘ON’’; thus the userwhowears the PDAmaybe 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