Schilling CJ · 2000
The study investigated effects of exposure to very high frequency radiofrequency radiation on six antenna engineers in two separate incidents. The first incident occurred in 1995 and the second in 1996. Six men were likely accidentally exposed to high levels of VHF radiofrequency radiation at 100 MHz while working on transmission masts, with four men in one incident and two in another. They experienced symptoms and signs including headache, paresthesiae, diarrhea, malaise, and lassitude. The condition of four men, two from each incident likely to have had the highest exposure, showed no significant improvement.
Wagner P et al. · 2000
Researchers aimed to investigate human sleep EEG under pulsed radio frequency electromagnetic fields using polysomnographies with submaximal high power flux densities. They applied a submaximal power flux density of 50 W/m(2). All-night polysomnographies were recorded from 20 healthy male subjects with and without exposure to a circularly polarized EMF at 900 MHz pulsed at 217 Hz with 577 microsecond pulse duration. The results showed no significant effect of the field application on conventional sleep parameters or sleep EEG power spectra.
Tsurita G, Nagawa H, Ueno S, Watanabe S, Taki M, · 2000
Male Sprague-Dawley rats were exposed to a 1439 MHz TDMA field. Exposure lasted one hour a day for two or four weeks. The study assessed blood-brain barrier permeability, cerebellar morphology, and body mass.
Sienkiewicz ZJ et al. · 2000
Reeves GI · 2000
Researchers reviewed medical records of 34 patients with confirmed RFR overexposure exceeding permitted limits to detect clinical or laboratory alterations correlated with power density or power density times exposure time. A sensation of warmth was positively associated with power density, while a negative correlation was observed between an abnormal tissue destruction screen and power density. Sophisticated neurological tests in 23 patients and extensive psychometric and psychological exams in 30 patients revealed no neurological or ophthalmologic findings attributable to RFR.
Oftedal G, Wilen J, Sandstrom M, Mild KH · 2000
Thirty-one percent of Norwegian respondents and 13% of Swedish respondents reported at least one symptom associated with mobile phone use. The most common symptoms were sensations of warmth on or behind the ear, burning sensations in the facial skin, and headaches. Most symptoms began during or within half an hour after the call and lasted for up to two hours. Relatively few participants consulted a physician or took sick leave, but about 45% of those with symptoms took steps to reduce them, and the authors concluded that the results suggest awareness of the symptoms but not necessarily a serious health problem.
Muscat JE et al. · 2000
Researchers conducted a case-control study in five US academic medical centers between 1994 and 1998 using a structured questionnaire, enrolling 469 adults with primary brain cancer and 422 matched controls. The median monthly hours of use were 2.5 for cases and 2.2 for controls, and the multivariate odds ratio for regular use was 0.85 (95% CI, 0.6-1.2). No association was observed according to duration of use (P = .54), and cerebral tumors occurred more often on the same side as phone use (26 vs 15 cases; P = .06) while temporal lobe tumors showed the opposite pattern (9 vs 5 cases; P = .33).
Morgan RW et al. · 2000
Researchers conducted a large cohort mortality study among 195,775 Motorola employees from 1976 to 1996, classifying workers into high, moderate, low, and background radiofrequency exposure groups. Standardized mortality ratios for radiofrequency-exposed workers were 0.53 for brain cancers and 0.54 for lymphomas and leukemias. Internal rate ratios were near 1.0 for brain cancers and below 1.0 for lymphomas and leukemias, with no increased risk seen with longer exposure duration or latency. The findings were consistent across different exposure classifications and did not support an association between occupational radiofrequency exposure and these cancers.
Marino C et al. · 2000
Researchers examined possible effects of 900 MHz microwave exposure on the cochlear epithelium of rats. Two experiments used male Sprague-Dawley rats with far-field exposure in a cubic chamber. No statistically significant evidence was obtained at both SAR values. The exposure system and diagnostic apparatus were considered useful for investigating auditory effects, but no evidence was observed with the parameters applied.
Lu ST et al. · 2000
Researchers studied retinal effects of 1.25 GHz high peak power microwaves in Rhesus monkeys. Preexposure and postexposure fundus pictures and angiograms were all within normal limits. Cone photoreceptor response to light flash was enhanced at 8.4 and 20.2 W/kg R-SAR but not at 4.3 W/kg R-SAR. Enhanced glycogen storage in photoreceptors was observed in sham, 8.4, and 20.2 W/kg groups but not in the 4.3 W/kg group. No degenerative changes or ERG depression were observed, and retinal injury was considered very unlikely at 4 W/kg.
Hietanen M, Kovala T, Hamalainen AM · 2000
Researchers analyzed EEG activity of 19 volunteers exposed to five different cellular phones operating at 900 MHz or 1800 MHz. Each subject completed six 30-minute experiments including one sham exposure, with real exposure lasting 20 minutes. Exposure to one phone caused a statistically significant change in absolute delta power, but relative delta power did not change and no effects were seen with other phones. The authors concluded that the observed difference was likely due to chance and that radiofrequency fields from cellular phones have no abnormal effects on EEG activity.
Bornhausen M, Scheingraber H · 2000
Wainwright P, · 2000
Researchers developed a finite element thermal model of the head to calculate temperature rises in the brain from cellular telephone radiation. The model used a 1 mm resolution MRI dataset segmented into ten tissue types and a finite element mesh generated with an automatic tetrahedral mesh generator. The model included natural metabolic heat production and power absorbed from the electromagnetic field, with SAR derived from a finite difference time domain model coupled to a model mobile phone. For publicly available equipment, the maximum temperature rise in the brain was about 0.1 °C. The steady-state temperature distribution was calculated using the Pennes bioheat equation.
Sidorenko A, Tsaryuk V · 2000
Researchers studied the effects of microwave radiation and strychnine on cerebral biopotentials in narcotized rats. Strychnine and microwave radiation produced changes in spectral parameters of electrocorticogram, correlation dimension, and Kolmogorov entropy opposite to those induced by urethane.
Schirmacher A et al. · 2000
Leshin VV · 2000
Researchers aimed to investigate changes in neurocytes of the central nervous system under general UHF field exposure with local protection applied. Experiments on white rats studied the influence of UHF field on the cortical sensomotor area under general exposure or with the head shielded. The changes in the central nervous system caused by UHF field were not completely prevented by the shield, which the authors attributed to pathologic reflex impulses from body receptors.
Kulkybaev GA, Pospelov NI · 2000
The study aimed to investigate changes in gastric electric activity and serum catecholamine levels under the influence of electromagnetic microwaves. Chronic experiments on 17 dogs revealed that ultrahigh-frequency electromagnetic waves applied to the epigastric area and head induced a double-phase response. During exposure, gastric electric activity was depressed and total catecholamines increased. After exposure, gastric activity was higher and epinephrine and norepinephrine levels were lower at 24 hours after each of 10 procedures and during 7 days after the 10 procedures.
Krause CM et al. · 2000
Researchers examined the effects of electromagnetic fields from cellular phones on event-related desynchronization and synchronization responses in four EEG frequency bands during cognitive processing. Twenty-four subjects performed a visual sequential letter task with three working memory load conditions both with and without exposure to a digital 902 MHz EMF in counterbalanced order. The presence of EMF altered the ERD/ERS responses in the 6-8 and 8-10 Hz frequency bands but only when examined as a function of memory load and depending on whether the stimulus was a target.
Krause CM et al. · 2000
Researchers studied the effects of cellular phone EMF on EEG frequency bands in 16 normal subjects performing an auditory memory task. All subjects completed the memory task with and without exposure to a digital 902 MHz EMF in counterbalanced order. EMF exposure significantly increased EEG power in the 8-10 Hz frequency band only. EMF presence altered ERD/ERS responses across all studied frequency bands depending on time and memory task phase.
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.
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.
Cox RA, Luxton LM · 2000
The study aimed to investigate cerebral symptoms from mobile telephones. Mobile phones affect the inner ear in 5-8% of users leading to dizziness, disorientation, nausea, headache and transient confusion.