Koivisto M, Krause CM, Revonsuo A, Laine M, Hamalainen H · 2000
The influence of pulsed radiofrequency (RF) electromagnetic fields of digital GSM mobile phones on working memory in healthy subjects were studied. Memory load was varied from 0 to 3 items in an n-back task, and each subject was tested twice with and without RF exposure at 902 MHz and 217 Hz. The RF field speeded up response times when the memory load was three items, but no effects were observed with lower loads. The results suggest that RF fields have a measurable effect on human cognitive performance and encourage further studies.
Koivisto et al. · 2000
The study examined possible influences of a 902 MHz electromagnetic field emitted by cellular telephones on cognitive functioning in 48 healthy humans. A battery of 12 reaction time tasks was performed twice by each participant in a counterbalanced order, once with and once without exposure to the field. Exposure speeded up response times in simple reaction time and vigilance tasks and decreased the cognitive time needed in a mental arithmetic task. The results suggest that exposure may have a facilitatory effect on brain functioning, especially in tasks requiring attention and manipulation of information in working memory.
Hocking B, Westerman R · 2000
Hardell L, Nasman A, Pahlson A, Hallquist A. · 2000
The study included 233 men and women aged 20 to 80 years with histopathologically verified brain tumors, with two matched controls selected per case from the Swedish Population Register. Of these, 209 cases (90%) and 425 controls (91%) completed the exposure questionnaire. Medical diagnostic x-ray examination of the head and neck region yielded an odds ratio of 2.10 (95% CI 1.25-3.53) for a tumor induction period of 5 years or more. Ipsilateral cellular telephone use was associated with an odds ratio of 2.42 (95% CI 0.97-6.05) for tumors in the temporal, temporoparietal, and occipital lobes.
Grajewski B et al. · 2000
Researchers measured RF heater radiation exposures and induced foot currents at four companies. They compared 12 male heater operators with 34 unexposed men on 33 semen quality parameters and four serum hormones. Exposures did not exceed current standard levels and guidelines. Exposed operators showed a slightly higher mean follicle-stimulating hormone level (7.6 vs 5.8 mIU/mL). The authors suggested further occupational studies of RF-exposed men may be warranted.
Fry TL, Schlegel RE, Grant H · 2000
Researchers measured hearing aid interference across a range of CDMA phone power levels using a frequency analyzer and several hearing aids and phones. As phone power increased, interference rose proportionally in a linear region until the hearing aid saturated, after which further power increases reduced or did not change interference. The interference data were combined with a previous study to assess effects on speech intelligibility and annoyance. Power reduction substantially improved interference for hearing aids with poor radiofrequency immunity, while high-immunity aids maintained low interference even at high power.
Freude, G, Ullsperger, P, Eggert, S, Ruppe, I, · 2000
Researchers studied the influence of electromagnetic fields emitted by cellular telephones on preparatory slow brain potentials in two experiments about six months apart. A significant decrease of slow brain potentials was found during EMF exposure in a complex visual monitoring task in the first experiment and this effect was replicated in the second experiment. The results indicated a selective EMF effect on particular aspects of human information processing but no influence on human performance, well-being and health.
Del Signore A, Boscolo P, Kouri S, Di Martino G, Giuliano G · 2000
Researchers studied immune responses to electromagnetic fields in atopic and non-atopic women with traffic exposure. Women were divided into groups A, B, C, and D based on atopy and electromagnetic field exposure. Atopic women had reduced in vitro lymphocyte proliferation when stimulated with PHA. Women exposed to electromagnetic fields had lower NK cell levels and lower interferon-gamma production. Atopic women exposed to electromagnetic fields had higher serum IgE than other groups.
Chia SE, Chia HP, Tan JS · 2000
Researchers conducted a cross-sectional community study in Singapore with 808 men and women aged 12 to 70 years selected by one-stage cluster random sampling. The prevalence of handheld cellular telephone users was 44.8%, and headache was the most prevalent symptom among users compared to nonusers with an adjusted prevalence rate ratio of 1.31 (95% CI 1.00-1.70). Headache prevalence increased significantly with increasing daily usage duration, while using hands-free equipment reduced headache prevalence by more than 20% compared to never using it. Handheld telephone use was not associated with a significant increase in other central nervous system symptoms.
Walters TJ, Blick DW, Johnson LR, Adair ER, Foster KR · 2000
Researchers measured cutaneous thermal pain thresholds in 10 human subjects during 3-second exposures to 94 GHz continuous wave microwave energy at intensities up to approximately 1.8 W/cm². Skin surface temperature increases were measured by infrared thermography during each exposure. The pricking pain threshold was 43.9°C, corresponding to an increase of approximately 9.9°C from a baseline of 34.0°C. The measured temperature increases agreed well with a simple thermal model accounting for heat conduction and microwave penetration depth. The results support using the model to predict thermal pain thresholds at other millimeter wave frequencies.
Peinnequin A et al. · 2000
Lebedeva NN et al. · 2000
EEG was recorded from 16 standard leads during eyes-open and eyes-closed conditions and analyzed with custom non-linear dynamics software that computed a multichannel global correlation dimension. A significant increase in global correlation dimension occurred during and after exposure, more pronounced with eyes closed. The authors interpreted this increase as a manifestation of cortex activation under phone EMF exposure.
Huber R et al. · 2000
Researchers exposed healthy young male subjects for 30 minutes to EMF at 900 MHz and a spatial peak specific absorption rate of 1 W/kg during the waking period before sleep. Compared with a sham exposure control condition, EEG spectral power during non-rapid eye movement sleep was increased, with the maximum rise in the 9.75-11.25 Hz and 12.5-13.25 Hz bands during the initial part of sleep. The researchers concluded that the changes of brain function induced by pulsed high-frequency EMF outlast the exposure period.
Harvey C, French PW · 2000
Researchers exposed a human mast cell line, HMC-1, to continuous wave microwave radiation at 864.3 MHz at an average specific absorption rate of 7 W/kg. Cells were given three exposures each of 20-min duration daily for 7 days. Expression of three genes out of 588 screened was affected, including the proto-oncogene c-kit, the transcription factor Nucleoside diphosphate kinase B, and the apoptosis-associated gene DAD-1. No significant effect on morphology or on F-actin distribution was detected.
Zotti-Martelli L, Peccatori M, Scarpato R, Migliore L · 2000
Researchers exposed human peripheral blood lymphocytes in vitro to electromagnetic fields at two frequencies, 2.45 and 7.7 GHz, at power densities of 10, 20, and 30 mW/cm2 for 15, 30, and 60 minutes. At a power density of 30 mW/cm2 and after exposures of 30 and 60 minutes, both frequencies led to an induction of micronuclei compared to control cultures. The researchers concluded that microwaves are able to cause cytogenetic damage in human lymphocytes mainly for both high power density and long exposure time.
Unknown authors · 1999
Unknown authors · 1999
HSP70 gene expression is induced by 60-Hz electromagnetic fields. Earlier work showed magnetic field induction occurs at the transcription level through c-myc binding at two nCTCTn sequences at -230 and -160. This study identified a third c-myc binding site between -158 and -162 that regulates magnetic field-induced HSP70 expression. The heat shock element between -180 and -203 is required for magnetic field induction, while the HSE at -100 alone is insufficient.
Unknown authors · 1999
Unknown authors · 1999
Researchers investigated symptoms and risk indicators of reported hypersensitivity to electricity using a survey at a telecommunications corporation and comparisons with referred patients. No association was found between psychosocial work characteristics or personal traits and hypersensitivity to electricity. Results indicate that skin symptoms, not neurovegetative symptoms, characterize the syndrome at least during the first years of illness.
Unknown authors · 1999
Researchers conducted a case-control study of 399 children with leukemia and 399 controls across five Canadian provinces from 1990 to 1994. Exposure assessment included 48-hour personal EMF measurement, wire coding, residential magnetic field measurements from conception to diagnosis, and 24-hour bedroom magnetic field measurement. Personal magnetic fields were not related to risk of leukemia (adjusted OR = 0.95, p for trend = 0.73) or acute lymphatic leukemia (OR = 0.93, p for trend = 0.64). No clear associations were found with predicted magnetic field exposure two years before diagnosis, over the lifetime, or with personal electric field exposure.
Unknown authors · 1999
Researchers conducted a double-blind laboratory study of 24 healthy young men to examine effects of intermittent versus continuous exposure to a 60 Hz, 28.3 microT magnetic field on EEG measures of night sleep. Intermittent exposure was associated with less total sleep time, reduced sleep efficiency, increased Stage II sleep, and decreased REM sleep, while continuous and sham exposure showed no such effects. Subjects exposed intermittently reported sleeping less well and feeling less rested in the morning compared to the other groups. All observed effects were significant at P < or = .04 or less.
Unknown authors · 1999
Unknown authors · 1999
Unknown authors · 1999
Researchers modeled and measured how 222Rn decay product aerosols behave in the 50 Hz electric field under high voltage power lines to assess increased exposure to airborne pollutants. The model predicted a two- to three-fold increase in aerosol deposition on spherical surfaces mimicking the human head. Experimental measurements using detectors on grounded metal spheres confirmed enhanced deposition of both 218Po and 214Po aerosols. Enhanced 218Po deposition on 400 kV lines ranged from 1.96 to 2.86 times, while 214Po deposition on 275 kV and 132 kV lines was 1.43 and 1.11 times, with the latter not significant.
Unknown authors · 1999
Researchers conducted a population-based case-control study across England, Wales, and Scotland. They measured household and school magnetic fields for 2226 matched case-control pairs and estimated average exposure in the year before diagnosis. For children with mean exposures above 0.2 microT compared to below 0-1 microT, the adjusted odds ratio for all malignant disease combined was 0.87 (95% CI 0.56-1.35).
