Unknown authors · 2009
Researchers conducted a confirmation study to test whether 915 MHz radiofrequency radiation alters the blood-brain barrier in rats. Unanesthetized rats were exposed for 30 minutes to continuous-wave or modulated 915 MHz energy at whole-body SARs of 0.0018 to 20 W/kg. Albumin immunohistochemistry on perfused brain sections showed no significant increase in albumin extravasation in exposed rats compared to sham-exposed or home cage controls.
Unknown authors · 2009
Air Force researchers exposed rats to 915 MHz radiofrequency radiation (similar to cell phone frequencies) for 30 minutes at various power levels to test whether it damages the blood-brain barrier. They found no detectable leakage of albumin proteins across this protective barrier, contradicting earlier studies from Lund University that reported blood-brain barrier damage from similar exposures.
López-Martín E et al. · 2009
Researchers studied whether pulse-modulated GSM radiation had different effects on brain activity than an unmodulated signal of the same wavelength, and examined c-Fos expression in seizure-related brain circuits. Rats made seizure-prone with picrotoxin and then exposed to GSM radiation showed differences in clinical and EEG signs and in c-Fos expression compared with picrotoxin-treated rats exposed to unmodulated radiation. The most marked effects of GSM radiation on c-Fos expression in picrotoxin-treated rats were observed in limbic structures, olfactory cortex areas, subcortical areas, the dentate gyrus, and the central lateral nucleus of the thalamic intralaminar nucleus group. Neither radiation treatment caused tissue heating, so the researchers ruled out thermal effects.
Dimbylow PJ, Nagaoka T, Xu XG. · 2009
The study compared foetal specific absorption rate (SAR) across three sets of pregnant female computational models. The models included a 26-week foetal model from the National Institute of Information and Communications Technology, Tokyo, and models at 13, 26, and 38 weeks from Rensselaer Polytechnic Institute. FDTD calculations were performed at a resolution of 2 mm for a plane wave with a vertically aligned electric field incident upon the body from the front, back and two sides from 20 MHz to 3 GHz under isolated conditions. The researchers compared external electric field values required to produce the ICNIRP public exposure localized restriction of 2 W kg(-1) when averaged over 10 g of the foetus with the ICNIRP reference levels.
Mizuno Y et al. · 2009
This was the first study to investigate the effects of the third generation system on regional cerebral blood flow in humans, comparing W-CDMA electromagnetic field exposure versus sham exposure. Nine healthy male volunteers participated and underwent PET scans before, during, and after 30 minutes of unilateral EMF exposure. The subtraction analysis showed no significant regional cerebral blood flow changes from the EMF conditions compared to sham exposure.
Unknown authors · 2009
The study examined the effects of pulsed EMF at 2.45 GHz and 2.8 mW/cm(2) on postnatal neurogenesis in newborn (P7) and senescent (24-month-old) rats. Two exposure patterns were compared: short-term exposure of 2 days at 4 hours per day and long-term exposure of 3 days at 8 hours per day, each followed by acute (24 hours) and chronic (1-4 weeks) post-irradiation survival periods. The EMF exposure induced significant age- and dose-dependent changes in proliferating cell numbers within the rostral migratory stream. The authors concluded that concerns about EMF risk from electrical equipment and communication sets are justified regarding early postnatal neurogenesis.
Unknown authors · 2009
Slovak researchers exposed newborn and elderly rats to 2.45 GHz microwave radiation (the same frequency as WiFi and microwaves) for 2-3 days and found significant disruption of brain cell development. The study showed that electromagnetic field exposure interfered with neurogenesis (new brain cell formation) in age- and dose-dependent ways, with effects lasting weeks after exposure ended.
Sannino A et al. · 2009
Researchers exposed human dermal fibroblasts from a healthy donor and a Turner's syndrome donor to 900 MHz RF radiation for 24 hours using a GSM-like signal at 1 W/kg, and Turner's syndrome fibroblasts were also exposed for 1 hour. For RF exposure alone, DNA damage was assessed with the alkaline comet assay and the cytokinesis-block micronucleus assay. RF radiation alone caused no genotoxic or cytotoxic effects in either cell line. MX increased DNA migration in the comet assay, but RF exposure did not enhance this MX-induced DNA damage.
Sannino A et al. · 2009
Researchers exposed human skin cells to 900 MHz radiofrequency radiation (the same frequency used by GSM cell phones) for 24 hours at power levels similar to phone use. They found no DNA damage from the RF radiation alone, and the radiation did not make cells more vulnerable to damage from a known cancer-causing chemical. This suggests that cell phone-level RF exposure may not directly break DNA strands in human cells.
Brescia F et al. · 2009
Researchers measured reactive oxygen species (ROS) production in human lymphoblastoid cells exposed to a 1950 MHz UMTS signal at Specific Absorption Rates of 0.5 and 2.0 W/kg. Exposures ranged from short durations of 5 to 60 minutes up to 24 hours, and the study also tested RF radiation given before or at the same time as ferrous ions. RF exposure did not increase ROS formation or affect cell viability, and combining RF with ferrous ions did not produce more ROS than ferrous ions alone.
Brescia F et al. · 2009
Researchers exposed human immune cells to 1950 MHz cell phone radiation (the frequency used by 3G networks) to see if it would trigger oxidative stress, a cellular damage process linked to aging and disease. They tested various exposure durations and power levels, both alone and combined with iron compounds known to cause oxidative stress. The study found no increase in harmful reactive oxygen species or cell death from the radiation exposure under any conditions tested.
Zareen N, Khan MY, Ali Minhas L · 2009
Embryos exposed for 10 post-incubation days showed decreased retinal growth and mild epithelial pigmentation. Extending exposure to 15 post-incubation days reversed growth retardation to enhancement and shifted pigmentation from mild to intense. The authors concluded that mobile phone EMF causes derangement of chicken embryo retinal differentiation. Retinal thickness and epithelial pigmentation grades were statistically compared between control and experimental groups.
Cao Y, Zhang W, Lu MX, Xu Q, Meng QQ, Nie JH, Tong J. · 2009
In this study, exposure to 900-MHz EMF expanded γ-ray damage to SHG44 cells. Preexposure EMF enhanced the decrease in cell proliferation induced by γ-ray irradiation and the rate of apoptosis. The combination of EMF and γ-ray exposure resulted in a synergistic effect by triggering stress response, which increased reactive oxygen species, but the expression of hsp70 at both mRNA and protein levels remained unaltered.
de Tommaso M et al. · 2009
Researchers tested how 900 MHz cell phone signals affect brain electrical activity by measuring a specific brainwave pattern called contingent negative variation (CNV) in 10 volunteers. They found that both active phones and sham phones (with internal circuits running but no RF emission) reduced brain arousal and expectation responses compared to phones that were completely off. The study suggests that both the GSM radio signal and the low-frequency magnetic fields from the phone's battery and circuits can alter normal brain function.
Garaj-Vrhovac V, Gajski G, Trosić I, Pavicić I · 2009
The animals were irradiated for 1h a day for 2 weeks at a field power density of 2.4W/m(2) and a whole-body average specific absorption rate (SAR) of 0.6W/kg. Both the standard comet assay and the Fpg-modified comet assay detected increased DNA damage in blood leukocytes of the exposed rats. The significant increase in Fpg-detected DNA damage suggests oxidative stress is likely responsible, while DNA damage detected by the standard comet assay indicates other mechanisms may also be involved.
de Tommaso M et al. · 2009
Researchers exposed 10 healthy volunteers to 900 MHz GSM cell phone signals and measured brain electrical activity using event-related potentials. Both active phones and sham phones (with electromagnetic power dissipated internally) reduced brain arousal responses compared to phones that were completely off. This suggests cell phone exposure affects brain electrical activity and attention processing.
Zhijian C et al. · 2009
Researchers used the in vitro comet assay to determine whether 1.8-GHz radiofrequency radiation can influence DNA repair in human leukocytes exposed to X-rays. Leukocytes from four young healthy donors were intermittently exposed to RFR at a SAR of 2 W/kg for 24 hours with fields on for 5 minutes and off for 10 minutes, then irradiated with X-rays at doses of 0.25, 0.5, 1.0 and 2.0 Gy. DNA damage was measured at 0, 15, 45, 90, 150 and 240 minutes after X-rays using percent tail DNA, and repair speed was assessed via DNA repair percentage. The results showed individual differences in DNA repair speeds among the four donors. Intermittent RFR exposure did not directly induce DNA damage or show synergistic effects with X-rays.
Ziemann C et al. · 2009
Researchers exposed male and female B6C3F1 mice to GSM 902 MHz and DCS 1747 MHz signals for two years. The exposure regimen was 2 hours per day, 5 days per week, at whole-body averaged SARs of 0.4, 1.3, and 4.0 W/kg. Micronuclei were counted in peripheral blood erythrocytes stained with May-Grunwald-Giemsa or acridine orange. No significant differences in micronuclei frequency were observed between RF-exposed, sham-exposed, and cage control mice. Positive control mice injected with mitomycin C had significantly increased micronuclei, and the authors concluded that the data did not indicate RF-induced genotoxicity after two years.
Moisescu MG, Leveque P, Verjus MA, Kovacs E, Mir LM. · 2009
The exposure increased Lucifer Yellow uptake, and this increase was not due to heating. Chlorpromazine and ethanol blocked the increase while Filipin did not, indicating involvement of clathrin-coated vesicles.
Acar GO, Yener HM, Savrun FK, Kalkan T, Bayrak I, Enver O. · 2009
Tissue temperature around the facial nerve was measured with a four-channel Luxtron fiber optic system and rose by 0.39 K during and immediately after exposure, returning to baseline after 25 minutes. Facial nerve compound muscle action potential amplitudes decreased significantly after exposure but returned to normal at the 25-minute measurement.
Amoako JK, Fletcher JJ, Darko EO. · 2009
Researchers surveyed radiofrequency electromagnetic radiation at public access points near cellular phone base stations operated by the Ghana Telecommunications Company. Measurements were made using a hand-held spectrum analyser to determine electric field levels within the 900 and 1800 MHz frequency bands. Power densities at public access points ranged from 0.01 to 10 microW m(-2) at 900 MHz, and from 0.01 to 100 microW m(-2) at 1800 MHz. The results were within international guidance levels but were 20 times higher than results generally obtained for such a practice elsewhere.
Söderqvist F, Carlberg M, Hansson Mild K, Hardell L · 2009
Researchers exposed 41 volunteers to cell phone radiation for 30 minutes and measured blood markers that indicate whether the blood-brain barrier (the protective shield around your brain) had been compromised. They found that one marker called transthyretin increased significantly after exposure, suggesting the radiation may have affected this critical barrier. This is concerning because a compromised blood-brain barrier could allow harmful substances to enter the brain more easily.
Trosić I, Pavicić I. · 2009
The study aimed to determine the influence of mobile phone frequency radiation on proliferation, cytoskeleton structure, and mitotic index of V79 cells after 1, 2, and 3 hours of exposure. V79 cells were exposed to continuous-wave 935 MHz radiation at an electric field strength of (8.2+/-0.3) V m(-1) and a specific absorption rate of 0.12 W kg(-1). Cell proliferation declined in cells exposed for three hours when measured 72 hours after irradiation. Microtubule structure was clearly altered immediately after three hours of irradiation. The mitotic index in exposed cells did not differ from negative controls.
Söderqvist F, Carlberg M, Hansson Mild K, Hardell L · 2009
Swedish researchers exposed 41 volunteers to 30 minutes of 890 MHz mobile phone radiation (1.0 W/kg) and measured blood markers that indicate if the blood-brain barrier was damaged. While one marker (S100B) showed no change, transthyretin levels increased significantly 60 minutes after exposure, suggesting possible barrier disruption.
Kwon MS et al. · 2009
Researchers recorded mismatch negativity responses to duration, intensity, frequency, and gap changes in 17 healthy young adults while a GSM phone was placed on either ear with the field on or off. The mismatch negativity was elicited by all deviant types, but its amplitude and latency showed no significant differences due to EMF exposure for any deviant type. The authors concluded there was no conclusive evidence that acute GSM mobile phone EMF exposure affects cortical auditory change detection processing reflected by the mismatch negativity.