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.
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.
Vijayalaxmi et al. · 2001
Researchers exposed peripheral blood samples from four healthy nonsmoking volunteers to 847.74 MHz CDMA radiation at SARs of 4.9 or 5.5 W/kg for 24 hours. Sham-exposed and gamma-irradiated (1.5 Gy) samples served as controls. No significant differences were found between RF-exposed and sham-exposed lymphocytes in mitotic indices, frequencies of exchange aberrations, excess fragments, binucleate cells, or micronuclei. Gamma-irradiated lymphocytes showed significantly different responses for all indices compared to both RF-exposed and sham-exposed cells. The authors concluded there was no evidence for induction of chromosome aberrations and micronuclei under these exposure conditions.
Vijayalaxmi et al. · 2001
Researchers exposed diluted peripheral blood from four healthy volunteers to 835.62 MHz RF radiation at SARs of 4.4 or 5.0 W/kg for 24 hours. Sham-exposed and gamma-irradiated (1.50 Gy) samples served as negative and positive controls, and lymphocytes were cultured for 48 or 72 hours to assess chromosomal aberrations, micronuclei, mitotic indices, and binucleate cells. No significant differences were found between RF-exposed and sham-exposed lymphocytes for any of the measured endpoints, while gamma radiation produced significantly different responses. The authors concluded there is no evidence for induction of chromosomal aberrations and micronuclei under these exposure conditions.
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.
Sandstrom M, Wilen J, Oftedal G, Hansson Mild K · 2001
Researchers conducted an epidemiological investigation including 6379 GSM users and 5613 NMT 900 users in Sweden, and 2500 from each category in Norway. The adjusted odds ratio did not indicate any increased risk for symptoms for GSM users compared with NMT 900 users. However, a statistically significant lower risk for sensations of warmth on the ear was observed for GSM users compared with NMT 900 users. A statistically significant association was found between calling time or number of calls per day and the prevalence of warmth behind or around the ear, headaches, and fatigue.
Roti Roti JL et al. · 2001
Researchers measured the effect of 835.62 MHz FDMA and 847.74 MHz CDMA radiation on neoplastic transformation frequency using the in vitro C3H 10T(1/2) cell transformation assay system. Cells were exposed at 37°C to either radiation at a specific absorption rate of 0.6 W/kg for 7 days to test for genotoxic effects, or after 4.5 Gy X-ray exposure for 42 days to test for epigenetic promotion effects. After both the 7-day and 42-day exposures, no statistically significant differences in transformation frequencies were found between incubator controls, sham-exposed groups, and RF-exposed groups.
Nelson BK, Snyder DL, Shaw PB · 2001
Researchers gave pregnant rats methanol at 0, 2, or 3 g/kg on gestation day 9 or 13, combined with RF radiation on day 9 or 2ME on day 13. On day 9, RF radiation or methanol increased fetal resorptions without interaction, and resorptions were highest when treatments were separated by 1.5 hours. The higher methanol dose also reduced fetal weights. On day 13, 2ME or methanol increased malformations with a positive interaction between them, while fetal weights were reduced by each agent alone without interaction.
Mason PA et al. · 2001
In this study we investigated whether a single (1.0 W/cm(2) for 10 s) or repeated (2 exposures/week for 12 weeks, 333 mW/cm(2) for 10 s) exposure to 94 GHz RFR serves as a promoter or co-promoter in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced SENCAR mouse model of skin carcinogenesis. Neither paradigm of MMW exposure significantly affected papilloma development, as evidenced by a lack of effect on tumor incidence and multiplicity. There was also no evidence that MMW exposure served as a co-promoter in DMBA-induced animals repeatedly treated with 12-O-tetradecanoylphorbol 13-acetate.
Maes A, Collier M, Verschaeve L · 2001
Researchers investigated cytogenetic effects of 900 MHz radiofrequency fields using chromosome aberration and sister chromatid exchange frequency methods. They studied three exposure modes (continuous, pseudo-random, dummy burst) at power outputs from 0 to 50 W. Specific absorption rates ranged from 0 to 10 W/kg. The study examined effects of radiation alone and combined with mitomycin C and X-rays. Overall, no mutagenic or co-mutagenic effect was found.
Koivisto M et al. · 2001
Researchers studied the influence of pulsed radiofrequency electromagnetic fields from digital GSM mobile phones (902 MHz, 217 Hz pulse modulation) on subjective symptoms in healthy subjects using two single-blind experiments. The results did not reveal any differences between exposure and non-exposure conditions. Exposure durations were about 60 minutes in Experiment 1 and 30 minutes in Experiment 2. Subjects rated symptoms including headache, dizziness, fatigue, itching or tingling of the skin, redness on the skin, and sensations of warmth on the skin.
Johansen C, Boice JD, McLaughlin JK, Olsen JH, · 2001
A retrospective cohort study in Denmark included 420 095 cellular telephone users from 1982 through 1995. Cancer incidence was determined by linkage with the Danish Cancer Registry. Overall, 3391 cancers were observed with 3825 expected, yielding a significantly decreased standardized incidence ratio of 0.89. No excess risk was found for brain or nervous system tumors, salivary gland cancer, or leukemia. The results do not support an association between cellular telephone use and these cancers.
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.
Inskip PD et al. · 2001
Researchers conducted a case-control study of intracranial tumors between 1994 and 1998. They enrolled 782 patients with glioma, meningioma, or acoustic neuroma and 799 controls. Cumulative use of more than 100 hours showed relative risks of 0.9 for glioma, 0.7 for meningioma, 1.4 for acoustic neuroma, and 1.0 for all tumors combined. No higher risks were seen for use of 60 or more minutes per day or regular use for five or more years. Tumors did not occur more often on the side of the head where the telephone was typically used.
Higashikubo R et al. · 2001
Researchers exposed mouse C3H 10T(1/2) fibroblasts and human U87MG glioma cells to two types of radiofrequency fields at 0.6 W/kg. Five cell cycle parameters including transit through G1, G2, and S phase and probability of cell division were measured immediately and up to 100 hours. No changes in cell cycle parameters were observed in exposed cells compared to sham-exposed cells in either cell line during the entire experimental period.
Heikkinen P et al. · 2001
Researchers evaluated the effect of low-level RF radiation on cancer development initiated by ionizing radiation in mice. Two hundred female CBA/S mice were randomized into four equal groups at 3 to 5 weeks of age, and all groups except the cage-control group were exposed to ionizing radiation followed by RF radiation for 1.5 h per day, 5 days a week for 78 weeks. One group received continuous NMT-type RF radiation at 902.5 MHz and 1.5 W/kg SAR, another received pulsed GSM-type RF radiation at 902.4 MHz and 0.35 W/kg SAR, while controls were sham-exposed. RF radiation exposures did not significantly increase the incidence of any neoplastic lesion. The researchers concluded that the results do not provide evidence for cancer promotion by RF radiation from mobile phones.
Li L et al. · 2001
Researchers exposed murine C3H 10T(1/2) fibroblasts to radiofrequency fields at specific absorption rates of 3.2 to 5.1 W/kg. Cell cultures were exposed to 847.74 MHz CDMA and 835.62 MHz FDMA modulated radiations in radial transmission line irradiators with temperature regulated to 37.0 ± 0.3 °C. Using the alkaline comet assay, they found no statistically significant differences in comet moment or comet length between sham-exposed and exposed cells after 2, 4, or 24 hours of exposure, for both exponentially growing and plateau-phase cells. A 4-hour incubation after a 2-hour exposure also resulted in no significant changes in comet moment or comet length. The authors concluded that exposure at 37°C up to 5.1 W/kg did not induce measurable DNA damage.
Westermark A, Wisten A. · 2001
The study aimed to investigate whether miniplate osteosynthesis and cellular phone create disturbance of the infraorbital nerve. Researchers measured electric current on the plate surface under the magnetic field between the phone antenna and the metal plate. The highest currents measured were 141 mV in air and 21 mV in saline. The findings suggested a possible correlation between the miniplate near the infraorbital nerve and patient dysesthesia under cellular phone energy.
Vitulli WF, Nemeth YM, Conte CT · 2001
The study determined whether ibuprofen causes a disruptive behavior pattern similar to aspirin yet contrary to acetaminophen regarding thermoregulatory effects. Eight Sprague-Dawley rats (3 males and 5 females) were conditioned in a refrigerated Skinner Box on a fixed-interval 2-minute schedule of microwave radiation (5 seconds per exposure) in a repeated-measures reversal design. Rats received intraperitoneal injections of ibuprofen at 10-50 mg/kg or methyl-cellulose control vehicle of equal volume over 8-hour daily sessions. A multivariate analysis showed significant differences due to ibuprofen doses for microwave heat reinforcers per hour and rate of responding (ns), with both measures significantly higher during the first two hours.
Tri JL, Hayes DL, Smith TT, Severson RP · 2001
Researchers tested 17 different medical devices with 5 portable telephones (4 digital, 1 analog) to assess electromagnetic interference. Any type of interference occurred in 7 of the 17 devices during 54.7% of the 526 tests. The incidence of clinically important interference was 7.4%. Most test results showed the interference would rarely be clinically important.
Stang A et al. · 2001
Silvi A M, Zari A, Licitra G · 2001
Researchers monitored electric-field levels produced by base stations of different typologies, including TACS, GSM, and DCS. The base stations were classified as either 'business' or 'residential'. On an hourly average basis, a daily curve of the exposure trend was constructed for these installations.
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.
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.
Peyman A, Rezazadeh AA, Gabriel C · 2001
Researchers measured dielectric properties of ten rat tissues at six ages from 130 MHz to 10 GHz. Results showed a general decrease in dielectric properties with age. The decrease was more apparent in brain, skull, and skin tissues than in abdominal tissues. The variation was attributed to changes in water content and organic composition.
