Pakhomova ON, Belt ML, Mathur SP, Lee JC, Akyel Y · 1998
Researchers exposed yeast cells to extremely high-intensity electromagnetic pulses (up to 104,000 volts per meter) after damaging them with UV radiation to see if the EMF exposure would worsen genetic damage. The ultra-wide band pulses, delivered at repetition rates of 16 Hz or 600 Hz for 30 minutes, showed no effect on DNA repair, mutation rates, or cell survival. This suggests that even very intense pulsed electromagnetic fields may not interfere with cellular DNA repair mechanisms.
Nakamura et al. · 1998
Researchers exposed pregnant rats to microwave radiation at 2.45 GHz for 90 minutes and found it suppressed natural killer cells, which fight infections and cancer. This immune suppression occurred through the body's opioid system, showing microwave exposure can weaken immunity during pregnancy when protection is most critical.
Kavaliers M, Choleris E, Prato FS, Ossenkopp K · 1998
Researchers exposed land snails to 60-Hz magnetic fields from power lines and found the fields disrupted the animals' natural pain relief systems by altering brain chemistry. This shows that common household electrical frequencies can interfere with basic biological processes controlling pain in living organisms.
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.
Malyapa RS et al. · 1998
Researchers exposed rats to microwave radiation at 2450 MHz (the same frequency used in microwave ovens) for 2 hours to test whether it causes DNA breaks in brain cells. They found no DNA damage in either the brain's cortex or hippocampus regions, contradicting an earlier study that reported such damage. This suggests that short-term exposure to this type of microwave radiation at moderate levels may not harm brain cell DNA.
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.
Lai H, Singh NP · 1997
Researchers exposed rats to 60-Hz magnetic fields (the same frequency as household electricity) and found that this exposure caused DNA breaks in brain cells. However, when the rats were given melatonin or another antioxidant compound before exposure, these protective substances completely blocked the DNA damage. This suggests that magnetic fields may damage DNA through free radical formation, and that antioxidants might offer protection.
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.
Malyapa RS et al. · 1997
Researchers exposed lab-grown cells to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and older WiFi) for up to 24 hours to see if it would damage DNA. Using a highly sensitive test called the comet assay, they found no DNA damage at either exposure level tested. This contradicted earlier studies that suggested microwave radiation could break DNA strands in brain cells.
Vijayalaxmi et al. · 1997
Researchers exposed cancer-prone mice to 2450 MHz radiofrequency radiation (the same frequency used in microwave ovens and some WiFi) for 20 hours daily over 18 months to test whether it causes DNA damage. They measured micronuclei - tiny fragments that indicate genetic damage - in blood and bone marrow cells. The study found no significant difference in DNA damage between exposed and unexposed mice, suggesting this level of RF exposure did not cause detectable genetic harm.
Litovitz et al. · 1997
Researchers exposed cells to microwave radiation from cell phones and found it increased activity of an enzyme called ornithine decarboxylase, which is linked to cell growth and potentially cancer. However, when they added low-frequency electromagnetic 'noise' during the exposure, it completely blocked these cellular effects. This suggests that certain types of electromagnetic interference might actually protect cells from microwave damage.
Gos, P, Eicher, B, Kohli, J, Heyer, WD · 1997
Researchers exposed yeast cells (Saccharomyces cerevisiae) to extremely high frequency electromagnetic fields around 41.7 GHz at very low power levels to see if the radiation affected how quickly the cells divided. After careful testing with proper controls, they found no significant differences in cell division rates between exposed and unexposed yeast. This contradicts some earlier studies that claimed to find biological effects from similar EMF exposures.
Jensh RP · 1997
Pregnant rats exposed to microwave radiation at cell phone and microwave oven frequencies showed concerning effects in offspring. The highest frequency (6000 MHz) caused delayed development, reduced birth weight, and altered brain function, suggesting certain microwave frequencies may affect developing brains.
Vijayalaxmi, Mohan, N, Meltz, ML, Wittler, MA, · 1997
Researchers exposed human blood cells to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and WiFi) for 90 minutes to see if it would damage DNA or affect cell growth. They found no genetic damage, chromosome breaks, or changes in how fast the cells multiplied compared to unexposed cells. This suggests that short-term exposure to this type of radiation at these power levels may not immediately harm human blood cells.
Vollrath L, Spessert R, Kratzsch T, Keiner M, Hollmann H · 1997
German researchers exposed rats and hamsters to 900 MHz radio frequency fields (similar to early cell phones) for up to 6 hours to see if it would affect their pineal glands, which produce the sleep hormone melatonin. They found no changes in melatonin production or pineal gland structure at any exposure level tested. This suggests that short-term RF exposure at these levels doesn't disrupt the body's natural sleep-wake cycle regulation.
Vorobyov VV, Galchenko AA, Kukushkin NI, Akoev IG · 1997
Russian scientists exposed rats to weak cell phone-like radiation (945 MHz) for 10 minutes and found immediate changes in brain wave patterns between left and right brain hemispheres within 20 seconds. This suggests microwave radiation can directly interfere with normal brain electrical activity.
Salford LG, Brun A, Persson BRR · 1997
Researchers injected brain tumor cells into 154 pairs of rats, then exposed half to 915 MHz microwaves (the frequency used by early cell phones) for 7 hours daily over 2-3 weeks while keeping the other half as controls. They found no difference in tumor growth between exposed and unexposed rats, suggesting that microwave exposure did not accelerate existing brain tumors in this particular experimental setup.
Nakamura H, Seto T, Nagase H, Yoshida M, Dan S, Ogino K. · 1997
Japanese researchers exposed pregnant and non-pregnant rats to microwave radiation at 2450 MHz (the same frequency used by microwave ovens and WiFi) for 90 minutes at 10 mW/cm². They found that pregnant rats showed significant immune system suppression, with reduced natural killer cell activity in the spleen, while non-pregnant rats showed no immune changes. The study reveals that pregnancy makes organisms more vulnerable to microwave radiation effects.
Klug S, Hetscher M, Giles S, Kohlsmann S, Kramer K, · 1997
German researchers exposed developing rat embryos to radio frequency electromagnetic fields at various power levels for up to 36 hours to test whether EMF exposure during critical development stages causes birth defects or growth problems. The study found no significant effects on embryo development, growth, or cellular structure across all tested exposure levels, including levels far exceeding typical telecommunication device emissions. This suggests that RF fields at these intensities may not pose developmental risks during embryonic growth.
Lai H, Carino MA, Singh NP · 1997
Researchers exposed rats to microwave radiation at 2.45 GHz for 2 hours and found significant DNA double strand breaks in brain cells. When they gave rats naltrexone (a drug that blocks the body's natural opioids), it partially prevented the DNA damage. This suggests that microwave radiation triggers the body's opioid system, which then contributes to genetic damage in brain tissue.
Lai, H, Carino, MA, Singh, NP, · 1997
Researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) for 2 hours and found it caused DNA double strand breaks in brain cells. When they gave the rats naltrexone, a drug that blocks the body's natural opioids, it partially prevented this DNA damage. This suggests the body's own opioid system plays a role in how microwave radiation damages DNA in brain cells.
Mason PA et al. · 1997
Researchers exposed rats to high-power 5.02 GHz microwave radiation, heating their brains to dangerous temperatures. This thermal stress significantly increased three amino acid concentrations in critical brain regions including the hypothalamus. The findings suggest microwave heating disrupts normal brain chemistry beyond temperature-control areas.
