Preece et al. · 1999
Researchers tested whether mobile phone signals at 915 MHz affect brain function by having 36 people perform cognitive tests while exposed to simulated phone radiation. They found that exposure made people react faster on choice reaction time tests, but had no effect on memory tasks. The faster reaction times suggest the phone signals may be affecting a specific brain region called the angular gyrus, which processes visual and speech information.
Borbely et al. · 1999
Researchers exposed healthy adults to cell phone radiation (900 MHz) during sleep using 15-minute cycles. The radiation reduced nighttime awakenings and changed brain wave patterns during deep sleep, showing that phone signals can directly affect brain function even at supposedly safe levels.
Velizarov, S, Raskmark, P, Kwee, S, · 1999
Researchers exposed cells to 960 MHz radiofrequency radiation (similar to cell phone signals) at different temperatures to test whether heat alone causes biological effects. They found that RF radiation altered cell growth patterns at both higher and lower temperatures, proving that the effects weren't simply due to heating. This challenges the mainstream assumption that only thermal effects from wireless radiation can impact living cells.
Fesenko, EE, Makar, VR, Novoselova, EG, Sadovnikov, VB, · 1999
Russian researchers exposed mice to low-level microwave radiation and found it significantly altered immune system function. Short exposures boosted immune cell activity, while longer exposure suppressed it. These effects persisted for days after radiation ended, showing even weak microwaves can disrupt normal immunity.
de Seze R, Ayoub J, Peray P, Miro L, Touitou Y · 1999
French researchers exposed 38 young men to cell phone radiation (GSM 900 MHz and DCS 1800 MHz) for 2 hours daily over 4 weeks to test whether it would disrupt melatonin, the hormone that regulates sleep cycles. They found no changes in melatonin patterns during or after exposure. This suggests that typical cell phone use may not directly interfere with the body's natural sleep hormone production.
Adair ER, Cobb BL, Mylacraine KS, Kelleher SA, · 1999
Researchers exposed 14 volunteers to radio frequency radiation at 450 and 2450 MHz (similar to cell phone frequencies) for 45 minutes at power levels exceeding current safety guidelines. The exposure caused measurable increases in skin temperature, with the body responding through increased sweating and blood flow to maintain normal core body temperature within 0.1 degrees Celsius.
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.
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.
Gandhi OP, Lazzi G, Tinniswood A, Yu QS, · 1999
Researchers compared computer calculations with actual measurements to determine how much radiofrequency energy cell phones deposit in human tissue (called SAR). They tested phones operating at cellular frequencies and found SAR levels ranged dramatically from 0.13 to 5.41 watts per kilogram, with some older-technology phones exceeding current safety limits of 1.6 W/kg unless antennas were carefully designed and positioned away from the head.
Morrissey JJ et al. · 1999
Researchers exposed mice to 1.6-GHz radiofrequency signals (similar to satellite phone frequencies) for one hour to see if it affected brain activity. They found that brain changes only occurred at exposure levels 6-30 times higher than current safety limits for cell phones, and these changes appeared to be caused by tissue heating rather than direct effects from the radiation itself.
Trosic I, Matausicpisl M, Radalj Z, Prlic I, · 1999
Researchers exposed rats to microwave radiation at 2450 MHz for two hours daily over 30 days. The exposed rats showed decreased white blood cells and increased red blood cells compared to controls, indicating the radiation affected their immune and blood systems.
Khadir R, Morgan JL, Murray JJ. · 1999
Scientists exposed human immune cells to 60 Hz magnetic fields at levels 440 times higher than household exposure. The fields amplified inflammatory responses when cells encountered other triggers, increasing harmful free radical production by 26.5%. This suggests power line frequencies may make immune systems overreact.
E.G Novoselova, E.E Fesenko, V.R Makar, V.B Sadovnikov · 1999
Researchers exposed mice to extremely low-power microwave radiation (8.15-18 GHz) for 5 hours and found it actually stimulated their immune systems, increasing production of immune signaling molecules and enhancing T cell activity. The immune boost was further enhanced when mice were given antioxidant nutrients like vitamin E and beta-carotene. This suggests that very low-level microwave exposure might trigger beneficial immune responses rather than suppress immunity.
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.
Schonborn F, Burkhardt M, Kuster N · 1998
Researchers used computer simulations to compare how much cell phone radiation is absorbed by children's heads versus adults' heads at 900 MHz and 1,800 MHz frequencies. They found no significant differences in radiation absorption between children and adults, contradicting earlier studies that suggested children absorb more radiation. This finding has important implications for safety standards, which are currently based only on adult head models.
Wagner, P, Roschke, J, Mann, K, Hiller, W, Frank, C · 1998
German researchers monitored the sleep patterns of 24 healthy men using brain wave measurements while exposing them to cell phone-like radiofrequency signals (900 MHz GSM signals). The study found no statistically significant changes in sleep quality, REM sleep duration, or brain wave patterns during EMF exposure. The researchers noted their failure to replicate previous findings might indicate that EMF effects on sleep depend on the specific exposure dose.
Malyapa RS et al. · 1998
Researchers exposed rats to 2450 MHz microwave radiation (the same frequency used in microwave ovens and some WiFi devices) for 2 hours to see if it would damage DNA in brain cells, as a previous study had suggested. They found no DNA damage in either the brain's cortex or hippocampus regions, contradicting the earlier research. This study suggests that short-term exposure to this type of radiation at moderate levels may not cause immediate genetic damage to brain cells.
de Seze R, Fabbro-Peray P, Miro L · 1998
French researchers exposed 20 healthy men to cell phone radiation for 2 hours daily over one month and measured six key hormones produced by the pituitary gland. They found no lasting changes in hormone levels, with only a temporary 21% decrease in thyroid-stimulating hormone that returned to normal after exposure ended. This suggests that typical cell phone use doesn't cause permanent disruption to the body's hormone control center.
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.
Imaida K et al. · 1998
Japanese researchers exposed rats to 929.2 MHz cell phone radiation for 90 minutes daily over 6 weeks to test whether the radiation could promote liver cancer development. The study used relatively high SAR levels (up to 7.2 W/kg) and found no difference in pre-cancerous liver lesions between exposed and unexposed rats. This suggests that cell phone radiation at these levels does not accelerate liver cancer progression in this animal model.
Imaida et al. · 1998
Researchers exposed rats to 1.439 GHz radiofrequency radiation (the type used in Japanese cell phones) to see if it would promote liver cancer development. Despite using exposure levels up to 1.91 W/kg and finding evidence of biological stress (increased stress hormones), the radiation did not increase cancer-promoting changes in the liver. This suggests that cell phone radiation at these levels does not accelerate liver cancer progression in this animal model.
Bassen HI, Moore HJ, Ruggera PS · 1998
Researchers tested how digital cell phones affect implantable cardioverter-defibrillators (ICDs), medical devices that shock the heart back into rhythm during dangerous arrhythmias. They found that phones using TDMA technology could cause ICDs to malfunction when held within 2-6 centimeters of the device, either preventing necessary pacing or triggering inappropriate high-voltage shocks. The interference stopped immediately when phones were moved away from the ICD.
Frei et al. · 1998
Researchers exposed 100 mice genetically prone to breast cancer to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and early WiFi) for 78 weeks, 20 hours per day. They found no difference in cancer rates between exposed mice (38%) and unexposed mice (30%), and no difference in how quickly tumors developed or grew. This suggests that chronic exposure to this specific level of microwave radiation did not increase breast cancer risk in these cancer-prone animals.
Walters TJ et al. · 1998
Scientists exposed rats to 2.06 GHz microwave radiation and measured brain temperatures. High-power microwaves created uneven heating patterns, with some brain areas heating 2-2.5 times faster than nearby regions. This uneven heating didn't occur with conventional heat sources like warm water.
Novoselova ET, Fesenko EE. · 1998
Russian researchers exposed mice to extremely weak microwave radiation (8.15-18 GHz at 1 microW/cm²) and found it significantly increased production of tumor necrosis factor in immune cells called macrophages. Tumor necrosis factor is a key protein that triggers inflammation and immune responses in the body. This suggests that even very low-power microwave radiation can alter immune system function.
