Sykes PJ, McCallum BD, Bangay MJ, Hooker AM, Morley AA. · 2001
Researchers studied the effect of pulsed 900 MHz radiofrequency radiation at 4 W/kg on somatic intrachromosomal recombination in the spleen of pKZ1 mice. Mice were exposed daily for 30 minutes to 900 MHz fields for 1, 5, or 25 days, and spleen sections were screened for DNA inversion events three days after the last exposure. There was no significant difference between control and treated groups in the 1- and 5-day exposure groups, but a significant reduction in inversions was found in the 25-day group.
Sykes PJ, McCallum BD, Bangay MJ, Hooker AM, Morley AA · 2001
Researchers exposed mice to 900 MHz radiofrequency radiation (similar to cell phones) for up to 25 days to see if it affected DNA recombination in spleen cells. They found no effects after short exposures, but after 25 days of exposure, DNA recombination actually decreased below normal levels. While this wasn't the DNA damage scientists typically look for, it suggests RF radiation can alter how cells repair their DNA, though the health significance of this change remains unknown.
Boscol P et al. · 2001
The study investigated the immune systems of 19 women with a mean age of 35 years who had been exposed to electromagnetic fields from radiotelevision broadcasting stations in their residential area for at least 2 years, with a mean exposure duration of 13 years. The exposed group had mean field levels of 4.3 plus or minus 1.4 V/m in the range 500 KHz to 3 GHz, while the control group had nearby residential exposure of less than 1.8 V/m. The exposed women showed statistically significant reductions in several immune cell types and lower in vitro production of IL-2 and interferon-gamma by peripheral blood mononuclear cells. The researchers concluded that high frequency electromagnetic fields reduce cytotoxic activity in the peripheral blood of women without a dose-response effect.
Santini R et al. · 2001
Researchers conducted a questionnaire survey of 161 students and workers at a French engineering school about symptoms during digital cellular phone use. Users of 1800-MHz phones reported significantly more concentration difficulties than users of 900-MHz phones. Women using cellular phones complained of sleep disturbance significantly more often than men. Using both cellular phones and VDT significantly increased concentration difficulties. Longer daily calling duration and more calls per day were associated with more ear discomfort, warmth, and pricking.
Unknown authors · 2001
Researchers demonstrated that a 50- to 60-Hz magnetic field interacts with cell differentiation through two opposing mechanisms. The field antagonizes the shift in cell membrane surface charges during early differentiation and modulates hyperpolarizing K channels by increasing intracellular calcium. The simultaneous onset of both mechanisms prevents alterations in cell differentiation. The authors propose that cells are normally protected against electromagnetic insult.
Jech R et al. · 2001
Paredi P, Kharitonov SA, Hanazawa T, Barnes PJ · 2001
Researchers exposed eleven healthy adults to a 900 MHz mobile phone for 30 minutes and measured skin temperature, nasal nitric oxide, and nasal minimal cross-sectional area. On the side of the phone, skin temperature rose significantly by 2.3°C at 6 minutes, nasal nitric oxide tended to increase by 12.9% at 10 minutes, and minimal cross-sectional area decreased by 27% at 15 minutes. These changes were absent when an earpiece was used, and the opposite side showed no temperature or nitric oxide change but a 38% increase in minimal cross-sectional area.
Paredi P, Kharitonov SA, Hanazawa T, Barnes PJ. · 2001
Researchers measured biological changes in 11 healthy adults during 30-minute cell phone calls using 900 MHz phones. They found significant increases in skin temperature (up to 2.3°C), reduced nasal airway space (27% decrease), and elevated nitric oxide levels on the side of the head where the phone was held. These effects disappeared when participants used earpieces instead of holding phones directly against their heads.
Sebastian JL, Munoz S, Sancho M, Miranda JM · 2001
Researchers calculated electric field intensity using the finite element method in single- and multilayer spherical, cylindrical, and ellipsoidal mammalian cell models exposed to 900 and 2450 MHz plane waves. They analyzed how cell geometry and orientation relative to the external field influence the electric field induced in the membrane and cytoplasm. The study found that cytoplasmic and extracellular bound water layers play a significant role in determining electric field intensity for cylindrical and ellipsoidal models.
Stagg RB et al. · 2001
Researchers exposed tube-restrained Fischer 344 rats to pulse-modulated 1.6 GHz Iridium cell phone fields at brain SARs of 0.16, 1.6 and 5 W/ kg for 2 hours. Core body temperature increased transiently by about 0.3 degrees C during the first 30 minutes of loose-tube restraint in conditioned animals. Immobilization alone caused a nearly 10-fold rise in ACTH and corticosterone in conditioned rats, and non-conditioned rats showed 3-10-fold higher hormone levels at 120 minutes. RF exposure did not change core body temperature, corticosterone, ACTH, or brain Odc, Fos, Jun mRNA compared with sham-exposed immobilized animals. The authors concluded that the pulse-modulated digital Iridium RF field at SARs up to 5 W/kg is incapable of altering these stress-related responses.
Vijayalaxmi et al. · 2001
Eight adult male Sprague-Dawley rats were exposed to 2450 MHz RFR in circularly polarized waveguides, and eight sham-exposed rats were kept in similar waveguides without RFR transmission. Four rats treated with mitomycin-C served as positive controls, and all rats were necropsied 24h after exposure to examine peripheral blood and bone marrow smears for micronuclei in polychromatic erythrocytes. The incidence of micronuclei per 2000 polychromatic erythrocytes was not significantly different between RFR-exposed and sham-exposed rats.
Unknown authors · 2001
Researchers induced dopamine neuron damage in newborn rats by infusing 6-OHDA into the brain ventricles on postnatal day 3. At two months of age, the rats were exposed to a 10 Hz, 1.8–3.8 mT magnetic field for one hour daily over 14 days, while a sham-exposed group had the solenoid turned off. After exposure, magnetic-field-exposed rats with dopamine damage showed reduced irritability and oral activity when given a D1 receptor agonist and increased catalepsy when given a D1 receptor antagonist. The authors concluded that extremely low frequency magnetic fields reduce the reactivity of central dopamine D1 receptors.
Unknown authors · 2001
Researchers examined responses of the small heat shock protein gene hsp-16 in transgenic Caenorhabditis elegans exposed to electromagnetic fields. Expression of the hsp-16-lacZ gene was enhanced when transgenic animals were exposed to magnetic fields up to 0.5 T at 60 Hz. The hsp-16 promoter was more efficiently expressed at the embryonic than at the post-embryonic stage irrespective of exposure. Promoter activity was more sensitive to the stimulus in the intestine at the post-embryonic stage.
Unknown authors · 2001
Unknown authors · 2001
German researchers exposed Syrian hamster embryo cells to 50 Hz magnetic fields (the same frequency as power lines) combined with known cancer-causing chemicals. They found that magnetic field exposure increased genetic damage by 80% when combined with the carcinogen benzo(a)pyrene. This suggests power line frequency fields may act as co-carcinogens, enhancing the effects of other cancer-causing agents.
Jauchem JR, Frei MR, Dusch SJ, Lehnert HM, Kovatch RM · 2001
Researchers exposed 100 C3H/HeJ mice to ultra-wideband electromagnetic pulses for 2 minutes once a week for 12 weeks, using 100 sham-control mice for comparison. There were no significant differences between groups in incidence of palpated mammary tumors, latency to tumor onset, rate of tumor growth, or animal survival. Histopathological evaluations also revealed no significant differences between the two groups in numbers of neoplasms across all tissues studied.
Unknown authors · 2001
The study examined 30 human volunteers. Volunteers were exposed to a 28 microT circularly polarized 50 Hz magnetic field for 50 minutes in a double-blind crossover design. The majority of cognitive measures showed no significant effect of exposure. Verbal recall of a 15-word list after interference was significantly impaired during field exposure. Performance on a trail-making task requiring executive functioning also decreased with exposure.
Unknown authors · 2001
Australian researchers tested 30 volunteers exposed to 28 microT 50 Hz magnetic fields (similar to occupational levels) for 50 minutes while performing cognitive tests. The study found significant impairment in short-term memory for word recall and decreased performance on executive functioning tasks requiring working memory. These findings suggest power frequency magnetic fields may affect specific brain functions related to learning and mental processing.
Cranfield CG, Wood AW, Anderson V, Menezes KG. · 2001
Researchers tested whether simulated GSM mobile phone signals at 915 MHz and 2 W kg(-1) influence calcium concentration or calcium signalling patterns in a human lymphocyte cell line. No significant changes were found in the regression slope of calcium fluorescence, mean calcium concentration, number of calcium spikes, or mean height of those spikes. A significant alteration in average frequency from Fourier spectra was found in one category only: pulsed wave exposure of activated cells.
Unknown authors · 2001
The study examined the effect of a sinusoidal 50 Hz magnetic field on preimplantation CBA/S mouse embryos in vitro. Embryos were exposed to a field of 10 A/m rms corresponding to 13 microT rms while cultured at 37°C in a CO2 incubator. Vitality and developmental stages were similar between groups, though slightly more dead embryos appeared on day 1 in the exposed group (P<0.05) and development was slightly impaired. The authors concluded that the exposure did not significantly disturb development up to the blastocyst stage.
Hanada E, Kodama K, Takano K, Watanabe Y, Nose Y. · 2001
Researchers measured electric field intensity from radio waves entering an 11-floor hospital that was under construction. The highest level recorded was about 200 V/m at 2.79 GHz, coming from airport surveillance radar. The maximum intensity from cellular phone base stations was 1.78 V/m. The researchers concluded that each hospital in urban areas should measure its own electromagnetic environment to help prevent interference with electronic medical equipment.
Trosic I. · 2001
Researchers exposed rats to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and some WiFi devices) and examined lung cells. They found that exposure caused immune cells in the lungs to fuse together into abnormal giant cells with multiple nuclei - a sign of chronic lung inflammation. The effect became stronger with more radiation treatments, suggesting cumulative damage to the respiratory system.
Novoselova EG, Ogai VB, Sorokina OV, Novikov VV, Fesenko EE · 2001
Researchers studied the effect of fractionated low-intensity microwave exposure and a combined weak magnetic field on tumor necrosis factor production in macrophages of mice with experimental solid tumors. Exposure to both microwaves and magnetic field enhanced the adaptive response, with higher tumor necrosis factor production in peritoneal macrophages of exposed tumor-bearing mice compared to unexposed mice.
Palfia Z, Somosy Z, Rez G · 2001
Researchers evaluated murine jejunal epithelial tight junctions after whole-body X-ray and microwave exposure using freeze fracture replicas. X-ray treatment at 4 Gy caused partial dearrangement of the ZO strand network that only partially regenerated by 24 hours. Microwave treatment at 16 Hz-modulated 2.45 GHz and 1 mW/cm2 for 1 hour did not cause dearrangement but increased integration of the tight junctional structure. The microwave effect agreed with an increase in cytochemically detectable ZO-bound calcium.
Radicheva N, Mileva K, Georgieva B, Kristev I · 2001
Researchers exposed isolated frog muscle fibers to continuous 2.45 GHz microwave radiation at 20 mW/cm² for one hour. Repetitive stimulation at 200 ms intervals evoked intracellular action potentials and twitch contractions. The twitch amplitude curve showed a drastic fall in the first 5 seconds followed by an increase and then a decrease. After microwave exposure, the changes in amplitude and time parameters that characterize fatigue were attenuated and delayed compared to controls. The authors concluded that microwaves have a specific non-thermal influence causing some resistance to fatigue.
