Gos P, Eicher B, Kohli J, Heyer WD · 2000
Scientists tested whether 900 MHz mobile phone radiation could damage DNA in yeast cells using multiple genetic tests. They found no evidence of mutations, DNA damage, or cellular dysfunction, even when combined with known toxic chemicals, suggesting these radiation levels may not directly harm genetic material.
Koivisto M, Krause CM, Revonsuo A, Laine M, Hamalainen H · 2000
Finnish researchers tested how cell phone radiation affects working memory by having participants complete memory tasks with and without exposure to GSM phone signals (902MHz). They found that phone radiation actually sped up response times when people had to remember three items at once, but had no effect on easier memory tasks. This suggests that cell phone radiation can measurably alter brain function and cognitive performance.
Schirmacher A et al. · 2000
Researchers exposed a laboratory model of the blood-brain barrier (the protective membrane that shields your brain from toxins in your blood) to cell phone radiation at 1.8 GHz. They found that this exposure significantly increased the barrier's permeability, allowing substances like sucrose to pass through more easily. This suggests that cell phone radiation may compromise the brain's natural protection system, potentially allowing harmful substances to reach brain tissue.
Bornhausen M, Scheingraber H · 2000
German researchers exposed pregnant rats to 900 MHz cell phone radiation throughout pregnancy to test whether prenatal EMF exposure affects brain development and learning ability. When the offspring reached adulthood, they showed no cognitive deficits or learning problems compared to unexposed rats. This suggests that low-level cell phone radiation during pregnancy may not impair brain development in rats.
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.
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.
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.
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.
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.
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.
Braune, S, Wrocklage, C, Raczek, J, Gailus, T, Lucking, CH · 1998
German researchers exposed 10 healthy volunteers to GSM 900 MHz cell phone radiation for 35 minutes while continuously monitoring their blood pressure and heart rate. They found that resting blood pressure increased during exposure to the phone's electromagnetic field compared to a placebo condition. This suggests that even short-term exposure to cell phone radiation can affect cardiovascular function in healthy individuals.
Kwee S, Raskmark P · 1998
Researchers exposed human cells to 960 MHz microwave radiation (similar to early cell phone frequencies) at different power levels and durations to see how it affected cell growth. They found that microwave exposure consistently reduced cell proliferation compared to unexposed control cells, with stronger fields requiring less exposure time to achieve maximum effects. This suggests that radiofrequency radiation can directly interfere with normal cellular processes in a dose-dependent manner.
Mann et al. · 1998
Researchers exposed healthy volunteers to 900 MHz electromagnetic fields (similar to older cell phones) while they slept and measured hormone levels throughout the night. They found a small, temporary increase in cortisol (stress hormone) right after exposure began, but no effects on growth hormone, reproductive hormones, or melatonin. The study suggests our bodies may quickly adapt to this type of EMF exposure.
Repacholi et al. · 1997
Scientists exposed genetically cancer-prone mice to 900 MHz radiofrequency fields (similar to cell phone signals) for 30 minutes twice daily for up to 18 months. The exposed mice developed lymphoma (a type of cancer) at 2.4 times the rate of unexposed mice. This suggests that cell phone-type radiation may accelerate cancer development in those already genetically susceptible.
Persson BRR, Salford LG, Brun A · 1997
Researchers exposed rats to 915 MHz microwave radiation (similar to cell phone frequencies) for periods ranging from 2 minutes to 16 hours and examined whether this damaged the blood-brain barrier, a critical protective shield that prevents toxins from entering brain tissue. They found that 39% of exposed rats showed abnormal leakage in their blood-brain barrier compared to only 17% of unexposed control rats. This suggests that wireless communication frequencies can compromise the brain's natural protective barrier, potentially allowing harmful substances to reach brain cells.
Roschke, J, Mann, K · 1997
German researchers exposed 34 healthy men to cell phone radiation (900 MHz) for 3.5 minutes while measuring their brain activity with EEG sensors. They found no detectable changes in brain wave patterns during the short exposure period compared to when the phone was turned off. This suggests that brief cell phone use may not immediately alter brain electrical activity in awake, healthy adults.