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.
Higashikubo R et al. · 1999
Researchers exposed rats with brain tumors to cell phone-like radiofrequency radiation for 4 hours daily over several months to see if the radiation would affect tumor growth. The study found no difference in survival rates between rats exposed to RF radiation and those that weren't exposed. This suggests that RF radiation at levels similar to cell phones doesn't accelerate brain tumor growth in this animal model.
Unknown authors · 1999
Swedish researchers exposed human leukemia cells to 50 Hz magnetic fields (the frequency used in European power systems) and measured calcium activity inside the cells. They found that magnetic field exposure reduced calcium oscillations in a dose-dependent manner, with stronger fields causing greater disruption. This matters because calcium signaling controls many essential cellular functions including immune responses.
Unknown authors · 1999
Researchers exposed human leukemia T-cells to 50 Hz magnetic fields (the same frequency as electrical power lines) and measured calcium oscillations inside the cells. They found that magnetic field exposure reduced these calcium signals in a dose-dependent manner - the stronger the field, the greater the reduction. This matters because calcium signaling is crucial for immune cell function and communication.
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.
Unknown authors · 1999
Researchers exposed human breast cells to 60 Hz magnetic fields at various strengths (0.1 to 10 Gauss) for up to 24 hours to test whether power line frequencies could trigger cancer-related gene changes. The study found no significant alterations in key cancer genes like c-myc, p53, and others, suggesting 60 Hz fields don't promote breast cancer through direct genetic mechanisms.
Unknown authors · 1999
Researchers exposed human breast cells to 60 Hz magnetic fields (the same frequency as household electricity) at various strengths for up to 24 hours to see if EMF exposure would alter cancer-related genes. The study found no significant changes in gene expression for key cancer markers like c-myc, p53, and others, suggesting 60 Hz magnetic fields don't promote breast cancer through genetic mechanisms.
Unknown authors · 1999
Researchers exposed human breast cells to 60 Hz magnetic fields at various strengths (0.1 to 10 Gauss) for up to 24 hours to test whether power line frequencies could trigger cancer-related gene changes. The study found no significant effects on cancer-associated genes including c-myc, p53, and others, suggesting 60 Hz EMF is unlikely to promote breast cancer through direct gene expression changes.
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.
Li et al. · 1999
Researchers exposed human cells to 837 MHz microwave radiation (the frequency used by early cell phones) for 2 hours at power levels ranging from 0.9 to 9.0 W/kg. They measured levels of TP53, a critical protein that normally increases when cells are damaged and helps prevent cancer formation. The study found no changes in TP53 levels up to 48 hours after exposure, suggesting these microwave frequencies did not trigger the cellular damage response.
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.
Paul Raj R, Behari J, Rao AR · 1999
Researchers exposed young rats to radiofrequency radiation at cell phone-like levels for 35 days and found significant changes in brain chemistry, including increased calcium movement and enzyme activity. These cellular changes in developing brains suggest RF exposure during growth may disrupt normal brain function.
Adey WR et al. · 1999
Researchers exposed pregnant rats and their offspring to cell phone radiation (836 MHz) for 24 months to study brain tumor development. Surprisingly, the radiation-exposed animals showed fewer brain tumors than unexposed controls, both naturally occurring tumors and those induced by a cancer-causing chemical. This unexpected protective effect was most pronounced in rats that died early in the study, where radiation exposure reduced chemically-induced brain tumors by a statistically significant amount.
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.
Unknown authors · 1999
The UK Childhood Cancer Study examined 2,226 children to determine if power line magnetic fields increase cancer risk. Researchers found no increased risk of childhood leukemia, brain tumors, or other cancers from magnetic field exposure. This large population study contradicts earlier research suggesting links between power line EMF and childhood cancer.
Unknown authors · 1999
German researchers exposed female rats to power line frequency magnetic fields (50 Hz, 100 microTesla) for 27 weeks while inducing breast cancer with a chemical carcinogen. The magnetic field exposure significantly increased mammary tumor development by 190% at 13 weeks and final tumor rates reached 64.7% in exposed rats versus 50.5% in controls.
Unknown authors · 1999
Researchers exposed blood samples from healthy volunteers to 50 Hz electromagnetic fields at various strengths (2-10 mT) and measured DNA damage using the comet assay. They found significant increases in DNA damage at nearly all exposure levels compared to unexposed samples, with women showing more damage than men.
Unknown authors · 1999
Researchers exposed human leukemia cells to 60 Hz power-line frequency magnetic fields at various intensities to see if they would activate key cellular signaling pathways called NF-kappaB and AP-1. Despite testing multiple field strengths up to 1.3 mT, they found no changes in these important cellular communication systems that regulate gene expression and immune responses.
Unknown authors · 1999
Swedish researchers exposed mice to 50 Hz magnetic fields (the same frequency as power lines) at 0.5 mT strength for different time periods. After 14 days of continuous exposure, brain cells showed significant DNA damage using a comet assay test. This suggests that prolonged exposure to power line frequency magnetic fields may be genotoxic to brain tissue.
Unknown authors · 1998
This 1998 review analyzed 29 studies examining whether electric and magnetic fields can damage DNA or cause genetic mutations. Despite finding 34 studies reporting positive genotoxic effects, the researchers concluded that none met basic scientific standards for independent reproducibility, consistency with known science, and complete data quality.
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.