Tri JL, Hayes DL, Smith TT, Severson RP · 2001
Researchers tested whether cell phones interfere with hospital heart and lung monitoring equipment by placing 5 phones (4 digital, 1 analog) near 17 different medical devices. They found that phones caused some type of interference in 41% of the devices tested, but only 7.4% of cases involved clinically significant problems that could affect patient care. This suggests that while electromagnetic interference from cell phones can occur in hospitals, serious disruptions to critical monitoring equipment are relatively rare.
Paredi P, Kharitonov SA, Hanazawa T, Barnes PJ. · 2001
Researchers measured biological changes in 11 healthy adults during 30-minute cell phone calls using 900 MHz phones. They found significant increases in skin temperature (up to 2.3°C), reduced nasal airway space (27% decrease), and elevated nitric oxide levels on the side of the head where the phone was held. These effects disappeared when participants used earpieces instead of holding phones directly against their heads.
Geller L, Thuroczy G, Merkely B. · 2001
Hungarian researchers tested how cell phones interfere with pacemakers by conducting over 1,100 lab tests and 130 tests with real patients. They found that older 450 MHz phones caused interference in 10-63% of cases, while newer GSM and 1800 MHz phones caused no problems. The study confirmed that keeping cell phones at least 20 centimeters (about 8 inches) away from pacemakers prevents any interference during normal use.
Chiladakis JA, Davlouros P, Agelopoulos G, Manolis AS. · 2001
Researchers tested digital cell phones (GSM and DCS 1800) on 36 patients with implantable cardioverter-defibrillators (ICDs) to see if the phones would interfere with these life-saving heart devices. While the phones caused some minor sensing errors when held very close to programming equipment, they did not damage the devices, trigger inappropriate shocks, or prevent proper pacing. The study concluded that digital cell phones pose no significant risk to patients with these specific ICD models.
Paredi P, Kharitonov SA, Hanazawa T, Barnes PJ · 2001
Researchers measured how 30-minute cell phone conversations affected nasal passages and skin temperature in 11 healthy adults. They found that the phone side of the face heated up by over 2 degrees Celsius, nasal passages narrowed by 27%, and nitric oxide levels increased, indicating blood vessel dilation. These effects disappeared when participants used a hands-free earpiece, proving the electromagnetic field was the cause.
Pashovkina MS, Akoev IG · 2001
Russian scientists exposed blood samples to weak microwave radiation for 1-3 minutes and found it changed enzyme activity at power levels thousands of times lower than cell phones emit. This shows even brief, low-level electromagnetic exposures can disrupt normal biological processes in blood.
Kainz W, Neubauer G, Alesch F, Schmid G, Jahn O. · 2001
Researchers reviewed published studies on how electromagnetic fields interfere with electronic medical implants like pacemakers and defibrillators. They found that mobile phones can disrupt these life-saving devices when held too close, particularly within 30 centimeters of the implant. The study recommends keeping phones at least 30 cm away from pacemakers and using them on the opposite side of the body from the implant location.
Lyskov E, Sandström M, Mild KH · 2001
Researchers exposed 20 people with electromagnetic hypersensitivity and 20 healthy controls to magnetic fields while monitoring their bodies. Magnetic fields didn't affect either group, but hypersensitive individuals showed different heart rate and stress patterns, suggesting they may have heightened sensitivity to environmental stressors generally.
Pakhomov AG et al. · 2000
Researchers exposed isolated frog heart tissue to extremely high-power microwave pulses (up to 350 million watts per kilogram) and compared the effects to lower-power continuous microwave exposure. Both exposure types caused the same temporary changes in heart rhythm that were directly proportional to heating, with no additional effects from the ultra-high power pulses. This suggests that microwave effects on heart function are purely thermal (heat-related) rather than caused by the electromagnetic fields themselves.
Jauchem JR, Ryan KL, Freidagger MR · 2000
Researchers exposed anesthetized rats to microwave radiation at 1 GHz, 10 GHz, or both frequencies combined at high power levels (12 W/kg) until the animals died from overheating. They found that rats exposed to 1 GHz died fastest, while those exposed to 10 GHz survived longest, with combined exposure falling in between. This study was designed to understand how different microwave frequencies affect heat distribution in the body and cardiovascular responses during extreme thermal stress.
Kalns J, Ryan KL, Mason PA, Bruno JG, Gooden R, Kiel JL. · 2000
Researchers exposed rats to 35-GHz microwave radiation and measured oxidative stress markers (cellular damage from harmful molecules) in various organs. They found that even brief microwave exposure caused a 5- to 12-fold increase in oxidative stress markers in the lungs, liver, and blood plasma before any circulatory problems developed. This suggests that microwave radiation triggers widespread cellular damage throughout the body, even at exposure levels that don't immediately cause obvious health effects.
Grant FH, Schlegel RE, · 2000
Researchers tested how wireless phones interfere with cardiac pacemakers at different distances, using laboratory conditions that mimicked the human torso. They found that even small increases in distance dramatically reduced interference - when phones were moved from 1 cm to 2 cm away from the pacemaker, half of the problematic interactions disappeared. The study revealed that keeping phones just 8.6 cm away perpendicular to the chest provides much better protection than the standard 15 cm recommendation measured horizontally.
Nakamura H, Nagase H, Ogino K, Hatta K, Matsuzaki I · 2000
Japanese researchers exposed pregnant rats to microwave radiation at 2.45 GHz (the same frequency as WiFi and microwave ovens) for 90 minutes and found it reduced blood flow to the placenta and increased stress hormones. The effects occurred at power levels too low to cause heating, suggesting the microwaves directly disrupted the pregnancy through biological mechanisms. This raises concerns about wireless device exposure during pregnancy.
Linz et al. · 1999
German researchers exposed isolated heart muscle cells from guinea pigs and rats to cell phone frequencies (900 MHz and 1800 MHz) to see if radio waves affected the cells' electrical activity. They found no significant changes to the heart cells' membrane potential, action potentials, or calcium and potassium currents even at exposure levels up to 880 mW/kg. The study suggests that cell phone radiation at these levels does not directly disrupt the basic electrical functions of heart muscle cells.
Jauchem JR, Frei MR, Ryan KL, Merritt JH, Murphy MR · 1999
Researchers exposed anesthetized rats to ultra-wideband electromagnetic pulses (extremely brief, high-intensity bursts of electromagnetic energy) to see if it affected their heart rate and blood pressure. They found no significant changes in cardiovascular function during the brief exposures. This suggests that short-term exposure to these specific types of electromagnetic pulses may not immediately harm the cardiovascular system.
Trigano AJ, Azoulay A, Rochdi M, Campillo · 1999
Researchers tested how walkie-talkies and cell phones interfere with external pacemakers (temporary heart devices used in hospitals). They found that 8 out of 9 pacemakers experienced dangerous disruptions from walkie-talkies, while 4 were affected by GSM phones and 2 by newer digital phones. The interference occurred at distances up to 6 feet away, potentially putting critically ill patients at risk.
Sakakibara Y, Mitsui T · 1999
Japanese researchers surveyed nearly 1,600 pacemaker patients about electromagnetic interference (EMI) problems they experienced in daily life. Mobile phones were the biggest concern (affecting 39% of patients), followed by MRI machines (17%) and common household devices like kitchen appliances. The study highlights how our increasingly electromagnetic environment creates real quality-of-life issues for people with implanted medical devices.
Occhetta E, Plebani L, Bortnik M, Sacchetti G, Trevi G · 1999
Researchers tested whether cell phones interfere with implantable cardioverter defibrillators (ICDs), life-saving devices that shock the heart back into normal rhythm during dangerous arrhythmias. They found that while phones caused significant interference with the telemetry system used to program the devices when placed directly on the ICD, they didn't cause false arrhythmia detections or prevent proper functioning when held normally by patients. The study concluded that ICD patients can safely use cell phones but should avoid them during device programming sessions.
Khudnitskii, SS, Moshkarev, EA, Fomenko, TV, · 1999
Russian researchers measured how cell phone radiation affects users' nervous systems, hearts, and body temperature during actual phone use. They found that the area of the head closest to the phone antenna experienced the most heating, and that the ultrahigh frequency radiation caused measurable changes in both brain function and cardiovascular activity. This study provides direct evidence that cell phones create biological effects beyond just heating tissue.
Belousova TE, Kargina-Terent'eva RA · 1999
Russian researchers exposed hypertensive rats to millimeter wave radiation at frequencies used in medical therapy devices (42,194 MHz and 53,534 MHz). They found the radiation reduced nerve density in heart tissue and decreased stress hormone production in both the heart and adrenal glands. This suggests millimeter wave exposure can suppress the sympathetic nervous system that controls heart rate and blood pressure responses.
Lu ST, Mathur SP, Akyel Y, Lee JC · 1999
Researchers exposed rats to ultrawide-band electromagnetic pulses (a type of radar technology) for just 6 minutes and measured their blood pressure for up to 4 weeks afterward. The exposed rats developed persistent low blood pressure (hypotension) that lasted for weeks, while their heart rate remained normal. This suggests that brief exposure to these high-intensity electromagnetic pulses can cause lasting cardiovascular effects.
Mann, K, Roschke, J, Connemann, B, Beta, H · 1998
Researchers monitored heart rate patterns during sleep in healthy adults exposed to radiofrequency fields from digital mobile phones. They found no changes in heart rate variability or the balance between the sympathetic and parasympathetic nervous systems (the body's automatic stress and rest responses) during EMF exposure compared to placebo conditions. The study suggests that weak pulsed RF fields from mobile phones don't disrupt the heart's natural rhythm control during sleep.
Jimenez A et al. · 1998
Spanish researchers tested whether cell phones interfere with implantable cardioverter defibrillators (ICDs), which are life-saving devices that shock the heart back to normal rhythm during dangerous arrhythmias. They found that while phones caused minor interference with monitoring signals, they did not affect the defibrillators' ability to detect or treat heart rhythm problems. The study concluded that cell phone use appears safe for ICD patients, though maintaining 15 cm (6 inches) distance is still recommended as a precaution.
Fetter JG, Ivans V, Benditt DG, Collins J, · 1998
Researchers tested whether digital cell phones interfere with implantable cardioverter-defibrillators (ICDs), life-saving devices that shock the heart back into normal rhythm when dangerous arrhythmias occur. Testing 41 patients with ICDs and various phone models, they found no interference with normal ICD function during typical phone use. However, placing a phone directly on top of an ICD (within half a centimeter) could temporarily disable the device's ability to detect dangerous heart rhythms.
Szmigielski et al. · 1998
Polish researchers studied 61 workers exposed to radiofrequency EMF at radio stations and compared their daily blood pressure and heart rate patterns to 42 unexposed workers. They found that EMF exposure disrupted the natural daily rhythms of both blood pressure and heart rate, with higher exposure levels causing more pronounced effects. This suggests that radiofrequency radiation may interfere with the body's autonomic nervous system, which controls these vital functions.
