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.
Urban, P, Lukas, E, Roth, Z · 1998
Researchers exposed 20 healthy volunteers to electromagnetic fields from a Motorola mobile phone for 5 minutes and measured visual evoked potentials (electrical brain responses to visual stimuli) to see if phone radiation affected brain function. They found no changes in brain activity after the exposure. This small pilot study suggests short-term mobile phone use may not immediately disrupt this particular aspect of brain function.
Schrader et al. · 1998
Researchers studied 193 soldiers at Fort Hood, Texas, examining sperm quality in men exposed to military radar versus those with no radar exposure. The study found no significant differences in sperm concentration, motility, or other measures of reproductive health between radar-exposed soldiers and controls. However, these results contradicted an earlier study by the same research team that found radar exposure decreased sperm counts, suggesting different types of military radar may have varying effects.
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.
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.
Dmoch A, Moszczynski P · 1998
Polish researchers studied immune system function in workers exposed to microwave radiation from TV transmission and satellite communication equipment (6-12 GHz frequencies). They found several changes in immune cell populations and antibody levels, including increased immunoglobulins (infection-fighting proteins) and altered ratios of different white blood cell types. However, the authors concluded these changes had no clinical significance, meaning they didn't appear to cause actual health problems.
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.
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.
Shckorbatov YG et al. · 1998
Ukrainian researchers exposed human cheek cells to millimeter wave radiation at 42.2 GHz and found it altered the cells' nuclei in two key ways: it reduced the electrical charge of the cell nucleus and increased chromatin condensation (DNA packaging became tighter). The effects varied based on radiation dose and individual differences between cell donors, suggesting that millimeter wave exposure can directly impact cellular structures at the genetic level.
Michelozzi P, Ancona C, Fusco D, Forastiere F, Perucci CA · 1998
Researchers investigated a cluster of leukemia cases near a high-power radio transmitter in Rome, Italy. They found that men living within 3.5 kilometers of the transmitter had 3.5 times higher leukemia death rates than expected, with risk declining significantly as distance from the transmitter increased. This suggests a potential link between proximity to radio frequency radiation sources and increased leukemia risk in men.
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.
Irnich W, Tobisch R · 1998
German researchers tested how mobile phones interfere with 224 life-saving medical devices like respirators and defibrillators across 2,016 different scenarios. They found that while interference can occur, dangerous situations are extremely rare because multiple factors must align simultaneously and medical devices have built-in safety features. The study concluded that blanket hospital bans on mobile phones are based on theoretical fears rather than actual evidence, recommending instead a simple 1-meter distance rule from medical equipment.
Hocking, B · 1998
Researchers surveyed 40 mobile phone users who experienced unusual symptoms like burning sensations and dull aches in their head and ears during or after phone calls. These symptoms typically started within minutes of use and lasted up to an hour afterward, with 75% of cases linked to digital phones. The study found that most people got relief by changing how they used their phones or switching to different devices.
Hardell L, Nasman A, Ohlson CG, Fredrikson M. · 1998
Swedish researchers studied 148 men with testicular cancer and 314 healthy controls to identify occupational risk factors. They found that men working with video display units (computer screens) had an 80% higher risk of testicular cancer after extended exposure (about 480 working days). Amateur radio operators, radar workers, and electronics engineers also showed elevated risks, though based on smaller numbers of cases.
Freude, G, Ullsperger, P, Eggert ,S, Ruppe, I · 1998
German researchers studied how cell phone radiation affects brain wave patterns by having men perform simple finger movements and complex visual tasks while exposed to phone emissions. They found that radiation significantly altered slow brain potentials (electrical patterns that prepare the brain for action) during the demanding cognitive task, but not during simple movements. This suggests cell phone radiation can interfere with brain electrical activity during mentally challenging activities, even when performance appears normal.
Eulitz, C, Ullsperger, P, Freude, G, Elbert ,T · 1998
German researchers examined how mobile phone radiation affects brain activity by measuring electrical responses while people listened to sounds. They found that phone radiation altered specific patterns of brain activity, particularly in higher frequency brain waves when people were actively processing important sounds. This suggests mobile phones can directly change how our brains process information.
Duan L, Shan Y, Yu X · 1998
Chinese researchers tested brain function in workers exposed to high-frequency electromagnetic radiation using standardized tests recommended by the World Health Organization. They found that exposed workers scored significantly lower on multiple brain performance measures compared to unexposed controls, and these changes correlated with symptoms of neurasthenia (a condition involving mental fatigue and cognitive difficulties). This suggests that occupational exposure to high-frequency EMF can measurably impair cognitive 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.
Bergdahl J, Tillberg A, Stenman E. · 1998
Swedish researchers examined 28 patients who reported health symptoms they believed were caused by electricity or computer screens (visual display units). The study found these patients had various dental and oral health problems, including jaw dysfunction, mouth burning, and reduced saliva production. While the study couldn't prove electricity caused these symptoms, it suggests that dental health issues might contribute to the suffering experienced by people who report electrical sensitivity.
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.
Szmigielski et al. · 1998
Researchers studied 61 workers exposed to radio frequency electromagnetic fields and found their natural daily blood pressure and heart rate patterns were disrupted - the normal peaks and valleys were flattened and shifted earlier, suggesting EMF exposure interferes with the body's cardiovascular rhythms.
Mickley GA, Cobb BL · 1998
Researchers exposed rats to microwave radiation at levels that caused significant body heating and found it disrupted their ability to distinguish between familiar and new objects - a key indicator of working memory function. However, rats that had been previously exposed to the heating developed a tolerance that protected them from both the temperature increase and memory problems. The study suggests that microwave-induced heating can impair cognitive function, but the brain may adapt to protect itself from repeated exposures.
Adair ER, Kelleher SA, Mack GW, Morocco TS, · 1998
Researchers exposed seven people to 450 MHz radio waves for 45 minutes to study heat effects. The RF energy increased sweating but participants' bodies successfully maintained normal core temperature through natural cooling. This shows human thermoregulation can handle these RF exposure levels effectively.
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.
