Miyakoshi J et al. · 2005
Researchers exposed human glioma MO54 cells to a continuous wave 1950 MHz RF field at SARs of 1, 2, and 10 W/kg for up to 2 hours. Cell growth was assessed by counting cell numbers up to 4 days after exposure. RF exposure at 2 and 10 W/kg did not affect the growth of MO54 cells. However, exposure at 10 W/kg for 1 and 2 hours significantly decreased the protein level of phosphorylated Hsp27 at serine 78.
Huber R et al. · 2005
Researchers investigated the effects of radio frequency electromagnetic fields similar to those emitted by mobile phones on waking regional cerebral blood flow in 12 healthy young men. Positron emission tomography scans were taken after 30 min unilateral head exposure to pulse-modulated 900 MHz RF EMF, and a sham control condition was also included. Only the 'handset-like' signal, which had stronger low-frequency components, increased relative cerebral blood flow in the dorsolateral prefrontal cortex on the side of exposure; the 'base-station-like' signal did not.
Trosic I, Busljeta I, Pavicic I. · 2004
Researchers investigated the effect of 2.45 GHz microwave irradiation on blood-forming cells in rats. Rats were exposed to a field power density of 5-10 mW/cm2 and a whole-body average SAR of 1-2 W/kg for 2 hours a day, 7 days a week, for 2, 8, 15, or 30 days. A significant decrease in lymphoblast count was observed at 15 and 30 days, while other examined parameters did not differ significantly from sham-exposed controls.
Aran JM et al. · 2004
In the first experiment, guinea pigs were exposed to GSM microwaves at SARs of 1, 2, and 4 W/kg for 1 hour per day, 5 days per week, for 2 months. In the second experiment, guinea pigs were exposed at 4 W/kg and auditory brainstem response thresholds were monitored. Repeated-measures ANOVA showed no difference in DPOAE amplitudes or ABR thresholds between exposed and sham-exposed groups. Acute exposure for 1 hour also produced no statistically significant change in ABR thresholds. In vitro, organs of Corti from newborn rats exposed to 1 W/kg for 24-48 hours appeared normal under light microscopy after 2-3 days of culture.
Dubreuil D, Jay T, Edeline JM. · 2003
Researchers exposed rats head-only to 900 MHz GSM electromagnetic fields at 1 and 3.5 W/kg for 45 minutes and compared performance with sham and control rats. In the first experiment, a slightly improved performance was found at 3.5 W/kg, but this was not seen in the delay task. In the third experiment, exploratory activity showed some effects but recognition memory was unaffected. Overall, the experiments provided no evidence that spatial or non-spatial memory is affected by this exposure.
Desta AB, Owen RD, Cress LW. · 2003
Researchers exposed L929 murine fibroblast cells to radiofrequency radiation from a time division multiple access wireless phone operating at 835 MHz to determine the effect on ornithine decarboxylase activity. Exposure lasted 8 hours at average specific absorption rates ranging from less than 1 W/kg up to 15 W/kg, after which cells were harvested and ODC activity was measured. No statistically significant difference in ODC activity was found between exposed and sham-exposed cells at non-thermal specific absorption rates. At SARs that caused measurable heating, a dose-dependent decrease in enzymatic activity was observed and was consistent with a comparable decrease caused by non-RF-radiation heating.
Gatta L et al. · 2003
Researchers exposed C57BL/6 mice to 900 MHz GSM-modulated radiation at SAR 1 or 2 W/kg for 2 hours per day over 1, 2, or 4 weeks. The number of spleen cells, percentages of B and T cells, and CD4/CD8 distribution were not altered by exposure. After 1 week of exposure, IFN-gamma production increased, but this effect was not seen after 2 or 4 weeks.
Dubreuil D, Jay T, Edeline JM. · 2002
Tice RR, Hook GG, Donner M, McRee DI, Guy AW. · 2002
DNA damage in leukocytes was assessed with the alkaline comet assay and chromosomal damage in lymphocytes with the micronucleus assay. No significant increase in DNA damage was seen after 3 or 24 hours, and no increase in micronucleated lymphocytes occurred after 3 hours. However, 24-hour exposures at 5.0 or 10.0 W/kg significantly increased micronucleated lymphocytes about fourfold, regardless of signal type, modulation, or frequency.
Zook BC, Simmens SJ, · 2001
Researchers exposed Sprague-Dawley rats to 860 MHz pulsed or continuous radiofrequency radiation for 6 hours per day, 5 days per week from 2 up to 24 months of age. The specific absorption rate was 1.0 W/ kg averaged over the brain. The rats were offspring of females injected intravenously with 0, 2.5, or 10 mg/kg ethylnitrosourea to induce brain tumors. There was no statistically significant evidence that the radiation induced neoplasia in any tissues or promoted cranial or spinal nerve or spinal cord tumors. The radiation had no statistically significant effect on brain tumor number, volume, location, multiplicity, histological type, malignancy, or fatality.
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.
Adey WR et al. · 2000
Researchers exposed Fischer 344 rats to a frequency-modulated signal at 836.55 MHz in a two-year bioassay, testing for effects on spontaneous and chemically induced central nervous system tumors. The study used six groups of offspring totaling 540 rats, with some groups receiving the chemical ENU and others sham or field exposure. No FM field-mediated changes were observed in number, incidence, or histological type of either spontaneous or ENU-induced brain tumors, nor were gender differences detected in tumor numbers.
Borbely et al. · 1999
Researchers exposed healthy young subjects during an entire night-time sleep episode to a 900 MHz electromagnetic field at a maximum specific absorption rate of 1 W/kg. The exposure schedule consisted of alternating 15-min on-15-min off intervals. Compared with a control night with sham exposure, the amount of waking after sleep onset was reduced from 18 to 12 min, and EEG spectral power in non-rapid eye movement sleep was increased. The researchers concluded that pulsed high-frequency EMF in the range of radiotelephones may promote sleep and modify the sleep EEG.
Frei et al. · 1998
Researchers exposed 100 C3H/HeJ mice to continuous-wave 2450 MHz RF radiation at 1.0 W/kg for 78 weeks, 20 hours per day, 7 days per week, while 100 mice were sham-exposed. There was no significant difference in mammary tumor incidence between exposed mice (38%) and sham-exposed mice (30%). Latency to tumor onset was similar: 62.5 weeks for exposed mice and 62.0 weeks for sham-exposed mice. Histopathological evaluation found no significant difference in malignant, metastatic, or benign neoplasms between groups.
D'Andrea JA, DeWitt JR, Portuguez LM, Gandhi OP. · 1988
Two experiments tested whether frequency-specific hotspot formation in the body and tail of rats would have behavioral consequences. Rats were placed in a cage where occupying one side triggered microwave exposure and occupying the other side ended it. Reduced exposure to 360-MHz and 2450-MHz microwaves at 1, 2, 6 and 10 W/kg were significantly different from 700-MHz microwaves. A second experiment found the threshold for reduced exposure to 2450-MHz microwaves fell between whole-body SARs of 2.1 and 2.8 W/kg.
T. F. Budinger · 1981
The document revises previous NMR instrumentation and clinical study guidelines based on new information and reanalysis. For static magnetic fields, harmful physiological or genetic effects are not expected below 2 T. For changing magnetic fields, the induced current effect threshold is above 5 mT at 1-100 Hz, though waveform, repetition rate, maximum B field, and exposure duration need further study. RF heating guidelines set a practical upper limit of a few watts for short studies under 10 minutes and 1 W/kg for long-term studies, with power absorption estimated via RF coil Q measurements.
Unknown authors · 1979
This 1979 technical report proposed threshold limit values (TLV) for radiofrequency radiation exposure in occupational settings. The document addressed workplace safety standards for microwave and RF electromagnetic energy, establishing guidelines for how much exposure workers could safely receive. This represents early efforts to regulate RF radiation before widespread consumer electronics adoption.
Unknown authors · 1979
Richard A. Tell · 1978
The report analyzes existing radiofrequency and microwave absorption data to examine frequency-dependent tissue heating and determine exposure field intensities linked to thermal loading on the whole body and specific tissues in adults and infants. A baseline absorption factor of 1 W/kg, equivalent to the adult basal metabolic rate averaged over total body mass, is used for comparison. In the 10 MHz to 1000 MHz range, absorption can produce whole-body thermal loads several times the basal metabolic rate at the present U.S. safety standard.
Richard A. Tell · 1978
This 1978 EPA technical report analyzed radiofrequency and microwave absorption data to evaluate thermal safety standards for human exposure. The study examined how RF and microwave energy is absorbed by biological tissue and assessed whether existing safety guidelines adequately protect against heating effects. This represents early government recognition that RF/microwave exposure needed systematic safety evaluation.
Richard A. Tell · 1978
This 1978 EPA technical report analyzed how radiofrequency and microwave radiation is absorbed by biological tissue, specifically examining thermal safety standards used to protect people from heating effects. The study represents early government efforts to establish exposure limits based on the assumption that heating is the primary health concern from RF radiation.
O. Balzano, O. Garay, F.R. Steel · 1970
This 1970 technical report examined RF energy exposure levels from portable radio operators using 30 MHz frequencies. Researchers used phantom models and tissue simulation techniques to measure how much radiofrequency energy was deposited in human tissue during radio operation. The study represents early efforts to quantify occupational RF exposure from handheld communication devices.
Ye W, Wang F, Zhang W, Fang N, Zhao W, Wang J. · 2015
Researchers examined the effects of mobile phone radiation on cardiovascular development in chicken embryos using a 900 MHz phone at a specific absorption rate of approximately 1.07 W/kg, applied intermittently for 3 hours per day during incubation. The rate of embryonic mortality and cardiac deformity increased significantly in the exposed group. Comet assay data showed the haemocyte mean tail in the exposed group was significantly larger than that of the control. The researchers suggest that long-term exposure may induce myocardium pathological changes, DNA damage, and increased mortality, but found little effect on vascular development.
Bilgici B, Akar A, Avci B, Tuncel OK. · 2013
Researchers exposed rats to a 900 MHz electromagnetic field at a whole body average specific absorption rate of 1.08 W/kg for 1 h/day for 3 weeks. Malondialdehyde and advanced oxidation protein product levels increased in rat brain tissue after exposure, suggesting increased lipid and protein oxidation. Garlic reduced the brain oxidative stress markers, though it did not affect the increase in serum nitric oxide levels. Nitric oxide levels in the brain showed no significant difference after exposure, but serum nitric oxide increased significantly.
Bilgici B, Akar A, Avci B, Tuncel OK · 2013
Researchers exposed rats to a 900 MHz electromagnetic field at a whole body average specific absorption rate of 1.08 W/kg for 1 hour per day for 3 weeks. Malondialdehyde and advanced oxidation protein product levels increased in rat brain tissue after electromagnetic field exposure. Nitric oxide levels in the brain showed no significant difference, but serum nitric oxide increased significantly after exposure, and garlic did not reduce that increase. The researchers also tested orally administered garlic powder at 500 mg/kg/day and found it had a protective effect against the oxidative stress seen in brain tissue.
