Dimbylow PJ, Hirata A, Nagaoka T. · 2008
The study intercompared the HPA male and female models NORMAN and NAOMI with the NICT male and female models TARO and HANAKO. Particular emphasis was placed on how dielectric properties are assigned to tissues such as skin and fat and on the consequences of different SAR calculation algorithms at higher frequencies. Whole-body SAR calculations were performed at three institutions for a vertically polarized plane wave incident on the front of the body from 30 MHz to 3 GHz under isolated conditions.
Hinrikus H, Bachmann M, Lass J, Karai D, Tuulik V. · 2008
Valbonesi P et al. · 2008
Researchers used the human trophoblast cell line HTR-8/SVneo to evaluate HSP70 and HSC70 protein and gene expression and primary DNA damage after nonthermal exposure to pulse-modulated 1817 MHz GSM-217 Hz waves for one hour at a SAR of 2 W/kg. Heat shock significantly enhanced HSP70 expression but not HSC70 expression. Exposure to high-frequency EMFs did not change HSP70 or HSC70 protein or gene expression. Hydrogen peroxide caused a significant increase in DNA strand breaks, but EMF exposure did not. Overall, no evidence was found that the exposure induced a HSP70-mediated stress response or primary DNA damage.
Curcio G et al. · 2008
The study investigated whether repeated brief exposures to a GSM mobile phone signal had a cumulative effect on psychomotor functions. After each of 3 15-min exposures, both an acoustic simple reaction time task and a sequential finger tapping task were administered to subjects. No cumulative effects were detected, though there was a non-statistical trend toward shorter reaction times.
Curcio G et al. · 2008
Italian researchers exposed 24 people to GSM mobile phone radiation (902.40 MHz) for three separate 15-minute sessions and tested their reaction times and finger coordination after each exposure. They found no measurable effects on psychomotor performance, though there was a slight non-significant trend toward faster reaction times. The study suggests that brief, repeated mobile phone exposures at typical power levels don't impair basic motor skills and reflexes.
Franzellitti S, Valbonesi P, Contin A, Biondi C, Fabbri E. · 2008
Researchers evaluated HSP70 gene and protein expression in human trophoblast HTR-8/SVneo cells after 4 to 24 hours of exposure to 1.8 GHz continuous-wave and GSM signals. Inducible HSP70 protein expression was not modified by any exposure condition. HSP70C transcript levels increased after 24 hours of GSM-217Hz exposure and decreased after 4 and 16 hours of GSM-Talk exposure, while HSP70A, HSP70B, and HSC70 transcripts did not change.
Mathur R. · 2008
Researchers exposed growing rats to a radiofrequency field (73.5 MHz amplitude modulated, 16 Hz, SAR = 0.4 w/kg) for 45 days at 2 hours per day and recorded their responses to several types of noxious stimuli. The tonic pain rating was also decreased (p < 0.01), which the researchers said indicates analgesia in response to tonic pain. The data suggest that amplitude modulated RF field differentially affects the mechanisms involved in the processing of various noxious stimuli.
Mathur R · 2008
Researchers exposed growing rats to AM radio frequency fields (similar to some communication systems) for 2 hours daily over 45 days and tested their pain responses. The exposed rats showed altered pain processing - they became more emotionally reactive to short-term pain but less sensitive to long-term pain. This suggests that chronic RF exposure during development can rewire how the nervous system processes different types of pain signals.
Kumar V, Vats RP, Pathak PP. · 2008
The study examined effects of electromagnetic waves at 41 and 202 MHz from a TV tower on human skin, muscles, bone, and fat. Researchers used international SAR exposure limits to calculate safe distances from TV transmission towers for both frequencies. The authors recommended that transmission towers be located away from densely populated areas and that people keep away from towers because they emit radiation harmful to some body tissues.
Yao K, Wu W, Wang K, Ni S, Ye P, Yu Y, Ye J, Sun L. · 2008
Researchers exposed cultured human lens epithelial cells (HLECs) to a 1.8 GHz GSM radiofrequency field for 2 hours at specific absorption rates of 1, 2, 3, and 4 W/kg, then measured intracellular reactive oxygen species (ROS) and DNA damage. After exposure to 1.8 GHz RF for 2 h, HLECs exhibited significant intracellular ROS increase in the 2, 3, and 4 W/kg groups, and RF at 3 W/kg and 4 W/kg induced significant DNA damage consisting mainly of single strand breaks. When the radiofrequency field was superposed with 2 μT electromagnetic noise, the noise blocked the RF-induced ROS increase and DNA damage.
Peyman A, Holden SJ, Watts S, Perrott R, Gabriel C · 2007
The dielectric properties of pig cerebrospinal tissues were measured in vivo and in vitro in the frequency range of 50 MHz-20 GHz. White matter and spinal cord showed significant variation as a function of animal age while no age-related variations were recorded for grey matter. The in vitro study included tissue from pigs weighing approximately 10, 50, and 250 kg to examine variation with age. Total combined measurement uncertainty was calculated at each frequency point and reported over representative frequency regions. Comparisons were made between the in vivo and in vitro data and with literature from the past decade.
Unknown authors · 2007
Researchers measured radiofrequency fields from wireless local area networks using Wi-Fi technology against background RF fields in the frequency range 75 MHz to 3 GHz. They conducted 356 measurements at 55 sites including residences, commercial spaces, healthcare and educational institutions, and other public spaces in the U.S., France, Germany, and Sweden. Measurements were taken under conditions that would result in the higher end of exposures, including close to Wi-Fi access points and at a distance of approximately 1 m from a laptop uploading and downloading large files. In all cases, measured Wi-Fi signal levels were very far below international exposure limits (IEEE C95.1-2005 and ICNIRP) and in nearly all cases far below other RF signals in the same environments.
Dimbylow P. · 2007
Researchers used finite-difference time-domain calculations to estimate SAR from 20 MHz to 3 GHz in hybrid voxel-mathematical models of the pregnant female. Mathematical models of the developing foetus at 8-, 13-, 26- and 38-week gestation were converted into voxels and combined with the reference adult female model, NAOMI at a resolution of 2 mm. The study calculated the electric field values needed to produce the ICNIRP public exposure restriction of 2 W kg(-1) when averaged over 10 g of the foetus.
Unknown authors · 2007
The paper discusses the phenomenon, mechanism, power requirement, pressure amplitude, and auditory thresholds of microwave hearing. Microwave pulse hearing involves electromagnetic waves from hundreds of MHz to tens of GHz, unlike normal hearing which uses sound pressure waves. The microwave auditory effect does not come from direct interaction with auditory nerves but from a thermoelastic wave launched by pulse absorption in soft tissues. This thermoelastic wave travels by bone conduction to the inner ear and activates cochlear receptors like normal hearing. The paper emphasizes human exposures to wireless communication fields and MRI coils.
Unknown authors · 2007
This 2007 study explains how humans and animals can actually hear microwave pulses, a phenomenon where electromagnetic waves create audible sounds inside the head. The research shows that pulsed microwaves heat tissue, creating pressure waves that travel through bone to the inner ear, where they're perceived as clicking or buzzing sounds. This finding has important implications for understanding exposure to wireless devices and MRI equipment.
Irlenbusch L et al. · 2007
Researchers exposed 33 people to GSM mobile phone signals near their eyes to test whether radiofrequency radiation affects visual sensitivity (the ability to detect light differences). Using exposure levels similar to holding a phone close to your face, they found no measurable changes in visual discrimination abilities during 30-minute exposure sessions. This suggests that typical mobile phone use doesn't immediately impair basic visual function.
Bachmann M et al. · 2007
Researchers studied how the human brain's bioelectrical activity adapted to low-level microwave exposure in a group of 14 healthy volunteers. The volunteers were exposed to 450 MHz microwave radiation modulated at 40 Hz frequencies, with a field power density at the scalp of 0.16 mW/cm(2). Results showed that an initial increase in EEG power was compensated and even overcompensated, with adaptation effects apparent in alpha and beta rhythms.
Zhao R, Zhang S, Xu Z, Ju L, Lu D, Yao G. · 2007
Researchers investigated whether 1800 MHz radiofrequency electromagnetic fields could influence gene expression in rat neurons. Among 1200 candidate genes, 24 were up-regulated and 10 were down-regulated after 24 hours of intermittent exposure at a SAR of 2 W/kg. The researchers concluded that gene expression in rat neurons could be altered by exposure to radiofrequency electromagnetic fields under their experimental conditions.
Christ A, Samaras T, Klingenböck A, Kuster N. · 2006
The study investigated electromagnetic near-field absorption in layered biological tissue from 30 MHz to 6000 MHz. Two effects can increase SAR in layered tissue versus homogeneous liquid: standing wave effects at larger distances depending on frequency and fat thickness, and high local skin absorption from reactive E-fields in the very close near-field. A conservative exposure estimate can be obtained by applying a multiplication factor of 1 to 3 to current dosimetric values.
Hamblin DL, Croft RJ, Wood AW, Stough C, Spong J. · 2006
Researchers tested 120 participants in a double-blind, counterbalanced, crossover design with two sessions one week apart. In both sessions, participants performed auditory and visual oddball tasks while EEG was recorded with a mobile phone set to sham exposure mounted over the temporal region, and then performed the same tasks while the handset was set to active or sham. No significant differences were found between exposure conditions for any ERP component or reaction time.
Krause CM et al. · 2006
Researchers collected EEG data from 15 children aged 10 to 14 years while they performed an auditory memory task with and without exposure to a 902 MHz mobile phone in counterbalanced order. During memory encoding, the active mobile phone modulated event-related desynchronization and synchronization responses in the approximately 4 to 8 Hz EEG frequencies. During recognition, the active mobile phone transformed brain oscillatory responses in the approximately 4 to 8 Hz and approximately 15 Hz frequencies.
Sun LX, Yao K, He JL, Lu DQ, Wang KJ, Li HW. · 2006
Cultured LECs were exposed to 217 Hz modulated 1.8 GHz microwave radiation at specific absorption rates of 0, 1, 2, 3, and 4 W/kg for 2 hours. DNA single strand breaks were detected with comet assay at 0, 30, 60, 120, and 240 minutes after irradiation. At 1 and 2 W/kg, the difference in DNA breaks between exposure and sham exposure groups was not significant at any detection time. At 3 and 4 W/kg, differences were significant immediately and 30 minutes after irradiation, with the difference disappearing after one hour in the 3 W/kg group but persisting in the 4 W/kg group.
Sun LX, Yao K, He JL, Lu DQ, Wang KJ, Li HW. · 2006
Researchers exposed human eye lens cells to cell phone radiation for 2 hours at different power levels. Lower levels caused repairable DNA damage, but higher power (4 W/kg) caused permanent breaks cells couldn't fix, suggesting a threshold where radiation overwhelms natural repair.
Sun LX, Yao K, He JL, Lu DQ, Wang KJ, Li HW. · 2006
Researchers exposed human eye lens cells to cell phone radiation for 2 hours at different power levels to see if it damages DNA. They found that lower exposure levels (up to 3 W/kg) caused temporary DNA breaks that the cells could repair, but higher exposure (4 W/kg) caused permanent DNA damage that cells couldn't fix.
Sun LX, Yao K, Jiang H, He JL, Lu DQ, Wang KJ, Li HW · 2006
Researchers exposed cultured human lens epithelial cells to 217 Hz modulated microwave radiation at four SAR levels for 2 hours. DNA single strand breaks were measured using the comet assay immediately after irradiation and at 30 and 60 minutes afterward. At the highest dose, significant DNA damage remained one hour after irradiation and cell proliferation was significantly decreased.
