Vijayalaxmi et al. · 1997
C3H/HeJ mice prone to mammary tumors were exposed to 2450 MHz RF radiation at 1.0 W/kg for 20 hours per day, 7 days a week, over 18 months, with sham-exposed controls and positive controls treated with mitomycin C. The incidence of micronuclei in peripheral blood and bone marrow did not differ significantly between RF-exposed and sham-exposed groups. Positive controls treated with mitomycin C showed significantly elevated micronuclei frequencies. A separate analysis of mice that developed mammary tumors also found no significant differences in micronuclei frequency between exposure groups.
Unknown authors · 1997
Researchers conducted a case-control study in northern Taiwan matching on date of birth, sex, and date of diagnosis to evaluate risks of adult leukemia, brain tumors, and female breast cancers in relation to residential exposure to 60-Hertz magnetic fields. The analysis included 870 leukemia cases, 577 brain tumor cases, and 1,980 female breast cancer cases. For leukemia, exposure to magnetic fields above 0.2 microtesla versus below 0.1 microtesla yielded an odds ratio of 1.4 (95% CI = 1.0-1.9), and living within 50 meters versus 100 meters or more from transmission lines gave a relative risk of 2.0 (95% CI = 1.4-2.9).
Litovitz et al. · 1997
Researchers exposed L929 cells to 60 Hz AM microwave fields or a 50 Hz burst-modulated DAMPS digital cellular phone field together with 30-100 Hz ELF noise up to 10 microT for 8 h. ODC enhancement decreased exponentially with increasing noise amplitude, with complete inhibition at 2 microT or higher for 60 Hz AM microwaves and 5 microT or higher for the DAMPS signal.
Unknown authors · 1997
Researchers used data from 12,063 Finnish twins who completed a depression inventory in 1990. Exposure was assessed using 20-year histories of distance to and calculated magnetic fields from 110- to 400-kV overhead power lines. Adjusted mean depression scores did not differ by exposure level. The risk of severe depression was 4.7 times higher for those living within 100 meters of a high-voltage line, though this was based on small numbers.
Gos, P, Eicher, B, Kohli, J, Heyer, WD · 1997
Researchers exposed exponentially growing Saccharomyces cerevisiae cells to electromagnetic fields from 41.682 GHz to 41.710 GHz in 2 MHz increments at power densities of 0.5 and 50 microW/cm2. Cell division was assessed by time-lapse photography using two identical chambers that allowed concurrent control and exposure experiments. Control experiments showed the cells were dividing at submaximal rates, ensuring that any increase or decrease in division rate could be observed. No consistently significant differences were found between exposed and unexposed cells across multiple independent experiment series.
Cleary, SF, Cao, G, Liu, LM, Egle, PM, Shelton, KR · 1997
Researchers investigated stress protein induction in HeLa and CHO cells following a 2-hour exposure to radiofrequency or microwave radiation. Cells were exposed under isothermal conditions maintained at 37 ± 0.2 °C. Neither microwave nor RF radiation had a detectable effect on stress protein induction.
Donnellan M, McKenzie DR, French PW · 1997
Researchers exposed a mast cell line, RBL-2H3, to 835 MHz radiation for 20 minutes, three times per day for 7 days at a power density of 8.1 +/- 3 mW/cm2. From day 4 onward, DNA synthesis and cell replication increased, cell morphology changed, and beta-hexosaminidase release was significantly enhanced compared to unexposed cultures. No effects were seen on cytoskeletal protein synthesis or beta-actin mRNA levels. Morphological changes persisted following subculture for at least 7 days in the absence of further exposure.
Donnellan M, McKenzie DR, French PW. · 1997
Researchers exposed immune cells called mast cells to cell phone radiation at 835 MHz for 20 minutes, three times daily for a week. They found that starting on day four, the cells began growing faster, changed shape, and became more reactive to chemical triggers. What's particularly concerning is that these changes persisted for at least a week after the radiation exposure ended, suggesting the effects may be long-lasting.
Fiorani M et al. · 1997
Researchers investigated the effects of 50 Hz magnetic fields (0.2–0.5 mT) on rabbit red blood cells exposed at the same time to an oxygen radical-generating system, Fe(II)/ascorbate. A 0.5 mT magnetic field had no effect on intact red blood cells, but when cells were already under oxidative stress, exposure caused a significant further decay in hexokinase activity of about 20% and a twofold increase in methemoglobin production. The researchers concluded that the magnetic fields studied were able to potentiate the cellular damage induced in vitro by oxidizing agents.
Jensh RP · 1997
This review examined whether chronic prenatal microwave exposure in rats caused adverse effects at birth or alterations in offspring development and growth. Pregnant rats were exposed throughout pregnancy to continuous wave 915 MHz, 2450 MHz, or 6000 MHz radiation at power density levels of 10, 20, or 35 mW/cm2, respectively. Animals exposed to 915 MHz did not exhibit any consistent significant alterations in any of the parameters measured. Offspring exposed to 6000 MHz showed an initial slight but significant retardation in term weight, delayed eye opening, lower weekly weights that recovered by the fifth week, and changes in water T-maze and open field performance.
Unknown authors · 1997
Researchers studied intracellular calcium signaling in Jurkat E6-1 human T-leukemia cells during and after exposure to a 60 Hz magnetic field. Cells were labeled with Fluo-3, stimulated with anti-CD3 antibody, and analyzed by flow cytometry for calcium-dependent fluorescence.
Unknown authors · 1997
Unknown authors · 1997
Vijayalaxmi, Mohan, N, Meltz, ML, Wittler, MA, · 1997
Vollrath L, Spessert R, Kratzsch T, Keiner M, Hollmann H · 1997
Researchers exposed male and female Sprague-Dawley rats and Djungarian hamsters to 900 MHz electromagnetic fields at 0.1 to 0.6 mW/cm2, continuous or pulsed at 217 Hz, for 15 min to 6 h. At day or night had no notable short-term effect on pineal melatonin synthesis in male and female Sprague-Dawley rats and Djungarian hamsters. Pineal synaptic ribbon profile numbers (studied in rats only) were likewise not affected The 900 MHz electromagnetic fields, unpulsed or pulsed at 217 Hz, as applied in the present study, have no short-term effect on the mammalian pineal gland.
Vijayalaxmi, Mohan N, Meltz ML, Wittler MA · 1997
Researchers exposed human blood cells to 2450 MHz radiofrequency radiation (microwave oven frequency) for 90 minutes and found no genetic damage or changes in cell division. The study tested both continuous and intermittent exposure patterns at power levels similar to some industrial microwave applications.
Bortkiewicz et al. · 1997
This study evaluated the circulatory system function of workers occupationally exposed to medium-frequency electromagnetic fields. The study included 71 workers at four AM broadcast stations operating at 0.738–1.503 MHz and 22 workers at radio link stations who had no history of regular electromagnetic-field exposure. ECG abnormalities were significantly more frequent in exposed workers than in non-exposed workers (75% versus 25%, p = 0.006), and a tendency for more rhythm disturbances was observed in AM broadcast station workers.
Vorobyov VV, Galchenko AA, Kukushkin NI, Akoev IG · 1997
Researchers studied averaged EEG frequency spectra in eight unanesthetized adult male rats with chronically implanted electrodes in symmetrical somesthetic areas during intermittent exposure to a weak 945 MHz microwave field amplitude-modulated at 4 Hz. Hemispheric asymmetry showed power decreases in the 1.5-3 Hz range on the left and in the 10-14 and 20-30 Hz ranges on the right hemisphere. No differences between control and exposure were found in averaged spectra over 10 or 1 minute periods. However, significant elevations of EEG asymmetry in the 10-14 Hz range occurred during the first 20 seconds after most microwave field onsets when spectra were averaged every 10 seconds.
Salford LG, Brun A, Persson BRR · 1997
Researchers used Fischer 344 rats of both sexes with implanted glioma cells (RG2 and N32) in a matched-pair design. Starting on day 5 after inoculation, rats were exposed for 7 hours a day, 5 days a week for 2–3 weeks to 915 MHz continuous or pulse-modulated microwaves. The study found no significant difference in tumour size between exposed and control animals. Tumour size was estimated as the volume of an ellipsoid after histopathological examination of all brains.
Nakamura H, Seto T, Nagase H, Yoshida M, Dan S, Ogino K. · 1997
Pregnant rats exposed to microwaves showed a significant reduction in splenic natural killer cell activity, while no such reduction was seen in exposed virgin rats. Corticosterone and ACTH increased, and oestradiol decreased, in both exposed virgin and pregnant rats, while beta-endorphin and progesterone increased significantly only in pregnant rats.
Cain CD, Thomas DL, Adey WR · 1997
The study tested whether a TDMA-modulated RF field and the tumor promoter TPA together increase focus formation of transformed cells cocultured with parental C3H/10T1/2 murine fibroblasts. Cell cultures were exposed to an 836.55 MHz TDMA-modulated field at specific absorption rates of 0.15, 1.5, and 15 μW/g in a repeating cycle of 20 minutes on and 20 minutes off continuously for 28 days. RF exposure did not significantly alter TPA-induced focus formation at any of the tested exposure levels across multiple independent experiments.
Klug S, Hetscher M, Giles S, Kohlsmann S, Kramer K, · 1997
Researchers exposed 9.5-day-old rat embryos for up to 36 hours to radiofrequency electric and magnetic fields with modulation frequencies of 16, 60, and 120 Hz. The exposure included electric field strengths of 60 and 600 V/m, magnetic inductions of 0.2 and 2.0 microtesla, and specific absorption rates of 0.2, 1.0, and 5.0 W/kg. Neither the electric nor the magnetic fields interfered significantly with normal embryo growth and differentiation when assessed on day 11.5 using a scoring system, photographs, histology, and protein content.
Lai H, Carino MA, Singh NP · 1997
Researchers exposed rats to 2450 MHz pulsed radiofrequency radiation at a power density of 2 mW/cm2 for 2 hours and then measured DNA double strand breaks in brain cells. The RFR exposure significantly increased DNA double strand breaks in rat brain cells, and the effect was partially blocked by naltrexone treatment. The researchers concluded that endogenous opioids play a mediating role in RFR-induced DNA strand breaks in brain cells of the rat.
Lai, H, Carino, MA, Singh, NP, · 1997
Researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) for 2 hours and found it caused DNA double strand breaks in brain cells. When they gave the rats naltrexone, a drug that blocks the body's natural opioids, it partially prevented this DNA damage. This suggests the body's own opioid system plays a role in how microwave radiation damages DNA in brain cells.
Unknown authors · 1997
Researchers reviewed studies on leukaemia risk among people living near high voltage transmission lines of 49 kV and above. They calculated combined risks for distances of 50 meters and 25 meters and for magnetic field exposures at 2, 3, 4, and 10 milligauss. The combined analysis showed an odds ratio of 1.3 with a 95% confidence interval of 1.0 to 1.7 for exposures of 2 milligauss or higher. Odds ratios increased at higher exposures of 3, 4, and 10 milligauss, and risks were also elevated at distances of 50 and 25 meters from the lines.