Lai H, Singh NP · 2004
Researchers investigated how magnetic field exposure affected brain cell DNA in rats. Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hours caused a significant increase in DNA single- and double-strand breaks, and prolonging the exposure to 48 hours caused a larger increase. Acute magnetic field exposure also increased apoptosis and necrosis of brain cells in the rat.
Koyama S et al. · 2004
Researchers tested whether an extremely low-frequency magnetic field (ELFMF) could affect mutations caused by hydrogen peroxide in pTN89 plasmids. Mutations were detected in the supF gene carried by the plasmids in Escherichia coli. The mutation frequency was 2.28×10−4 for hydrogen peroxide treatment alone, and 5.81×10−4 when the ELFMF was applied at the same time. No mutations were observed with ELFMF exposure alone, and the researchers indicated that the ELFMF may potentiate hydrogen peroxide-induced mutation.
Ding GR et al. · 2004
Researchers tested whether exposure to an extremely low frequency magnetic field affects hydrogen peroxide-induced cell death in human leukaemia HL-60 cells. Simultaneous treatment with the magnetic field and hydrogen peroxide for 24 hours significantly increased the number of apoptotic and necrotic cells compared with cells treated with hydrogen peroxide alone. The researchers found that active caspase-7 protein levels were higher in cells exposed to both the magnetic field and hydrogen peroxide than in those treated with hydrogen peroxide alone, and that poly(ADP-ribose) polymerase cleavage occurred earlier under combined exposure.
Sarimov R et al. · 2004
Researchers exposed lymphocytes from seven healthy persons to GSM microwaves at different frequencies in the range of 895-915 MHz and measured changes in chromatin conformation. A 30-min exposure at 900 and 905 MHz produced statistically significant condensation of chromatin in lymphocytes from 1 of 3 tested donors. Stronger effects were found following 1-h exposure, with chromatin condensation in 3 donors and decondensation in 1 donor. The observed chromatin changes were similar to effects of heat shock within the temperature window of 40/spl deg/C-44/spl deg/C.
Trosic I, Busljeta I, Modlic B. · 2004
Researchers used an erythrocyte micronucleus assay to investigate genetic damage in bone marrow red cells of rats exposed to radiofrequency/microwave radiation. Wistar rats were exposed to a 2.45 GHz continuous field for 2 hours daily, 7 days a week, at a power density of 5–10 mW/cm2, with a whole body average specific absorption rate calculated to be 1.25 ± 0.36 W/kg. Significant differences in polychromatic erythrocytes were found on experimental days 8 and 15, and the frequency of micronucleated polychromatic erythrocytes was also significantly increased on day 15. Comparisons after 2, 8, and 30 irradiation treatments did not reveal statistically significant differences between sham-exposed and treated subgroups.
Busljeta I, Trosic I, Milkovic-Kraus S. · 2004
The study observed erythropoietic changes in rats subchronically exposed to radiofrequency microwave radiation at a nonthermal level. Adult male Wistar rats were exposed to 2.45 GHz continuous RF/MW fields for 2 hours daily, 7 days a week, at 5 – 10 mW/cm2. In exposed animals, erythrocyte count, haemoglobin and haematocrit were increased in peripheral blood on irradiation days 8 and 15. Anuclear cells and erythropoietic precursor cells were significantly decreased in the bone marrow on day 15, while micronucleated cells' frequency was increased.
Unknown authors · 2003
Researchers restrained rats within the bore of 7 or 14 T superconducting magnets for variable durations and assessed behavioral effects by scoring locomotor activity after release and measuring conditioned taste aversion acquisition after pairing a glucose and saccharin solution with magnetic field exposure. Magnetic field exposure at either 7 or 14 T suppressed rearing and induced tight circling. The direction of circling depended on the rat's orientation: head-up exposure produced counterclockwise circling while head-down exposure produced clockwise circling. Conditioned taste aversion was induced after three pairings with 30 minutes of 7 T exposure or after a single pairing with 1 minute of 14 T exposure.
Zeni, O., Schiavoni, A. · 2003
Researchers exposed human peripheral blood lymphocytes from 20 healthy donors to 900 MHz electromagnetic fields under various conditions. Exposures included continuous-wave and GSM-modulated signals at specific absorption rates of 1.6 W/kg and 0.2 W/kg with different intermittent patterns. No statistically significant differences were found in micronucleus frequency or cell cycle kinetics across any exposure condition.
Scarfi MR et al. · 2003
The study aimed to investigate the genotoxic effect of THz radiation on human peripheral blood lymphocytes after 20 minutes of exposure to 1 mW average power Free Electron Laser radiation at 120-140 GHz. Nine healthy donors were employed and the cytokinesis block technique was used to measure micronucleus frequency and cell proliferation. The results indicated that the electromagnetic conditions did not alter micronucleus frequency or cell proliferation, suggesting no direct chromosomal damage or cell cycle alteration (p > 0.05).
McNamee, J. · 2003
Unknown authors · 2003
Researchers exposed CHO-K1 cells to high-frequency electromagnetic fields for 18 hours at SARs of 13, 39, and 50 W/kg and found no increase in micronucleus frequency compared to sham-exposed cells. At higher SARs of 78 and 100 W/kg, micronucleus frequency increased significantly in the middle well at 100 W/kg and in the outer well at 78 W/kg. When combined with bleomycin, exposure at 100 W/kg in the middle well and 78 W/kg in the outer well further increased micronucleus frequency beyond bleomycin alone. A high-temperature control at 39°C also significantly increased micronucleus frequency.
Unknown authors · 2003
The study investigated electrosensibility in 708 adults aged 17 to 60 years using perception thresholds to 50 Hz electric currents. Analysis of perception threshold distributions revealed a subgroup with significantly increased electrosensibility that could be differentiated from the general population. The variation in electrosensibility was significantly larger than estimated by nonionizing radiation protection bodies but much smaller than claimed by hypersensitivity self-aid groups. The investigation method presented is capable of exclusion diagnostics for persons suffering from the hypersensitivity syndrome.
Unknown authors · 2003
The study evaluated associations between suicide and occupational exposure to electromagnetic fields, pesticides, and hydrocarbon solvents. It used 11,707 suicide deaths and 132,771 controls from U.S. death certificates for 1991 and 1992. Exposure was assigned based on job title on the death certificates. Electromagnetic fields and pesticides showed weak associations with suicide risk, while hydrocarbon solvents showed little evidence of increased risk. The electromagnetic field association was highest for ages 20 to 35 (OR = 1.5) and the pesticide association was highest for ages 35 to 49 (OR = 1.5).
Unknown authors · 2003
This nested case-control study examined 387 prostate cancer deaths and five controls per case among US electric utility workers. Workers in the highest 10 percent of EMF exposure had an odds ratio of 2.02 for prostate cancer mortality after adjustment for PCB exposure, race, and active work status within the past 2 years. The odds ratio for PCB exposure and prostate cancer mortality was 1.47 with a 95% confidence interval of 0.97 to 2.24 after adjustment for suspected confounding factors. Exposure to high levels of both EMFs and PCBs showed no association with prostate cancer mortality.
Unknown authors · 2003
Residential magnetic field exposure was calculated as a time-weighted average from 1967 until diagnosis using distance, line configuration, and current load, while occupational exposure was classified by an expert panel into three levels based on hours per week above background. The two highest residential exposure categories showed increased odds ratios for women (2.01 and 2.68) but not for men (1.70 and 1.37), and occupational exposure showed no significant association.
Unknown authors · 2003
Researchers studied 15 men chronically exposed to 50-Hz magnetic fields for 1–20 years and 15 unexposed controls. Exposure levels for the exposed group ranged from 0.1 to 2.6 μT weekly geometric mean. Blood samples were taken hourly from 2000 to 0800 and nighttime urine was also collected and analyzed. The study found no changes in plasma melatonin, urinary 6-sulfatoxymelatonin, or circadian rhythm in the exposed group.
Unknown authors · 2003
Researchers isolated pineal glands from Wistar rats at 10:00 h and exposed them to a 50 Hz, 1 mT magnetic field for 4 hours in vitro. Basal melatonin release and enzyme activities were unchanged by magnetic field exposure alone. When magnetic field exposure preceded norepinephrine addition by 30 minutes, NAT activity, HIOMT activity, and melatonin release increased significantly. This effect did not occur when magnetic field and norepinephrine were applied together or in sonicated glands.
Unknown authors · 2003
The article reviews potential health risks from residential and occupational EMF exposure. It examines data from laboratory, epidemiology, and clinical studies along with field measurement surveys and exposure guidelines. Evidence for an association between EMF and childhood cancer is limited but warrants further investigation. Evidence linking EMF exposure to adult cancers from occupational settings is inconsistent and precludes clear conclusions. There is little evidence of an association between EMF and noncancer health effects.
Unknown authors · 2003
Unknown authors · 2003
Researchers exposed cultured fibroblasts from six healthy donors of different ages to intermittent ELF-EMF at 50 Hz and 1 mT for 1 to 24 hours. Basal DNA strand break levels correlated with donor age. The maximum DNA strand break response occurred at 15 to 19 hours of exposure. This response was more pronounced in cells from older donors, suggesting an age-related decrease in DNA repair efficiency.
Unknown authors · 2003
Researchers exposed cultured human diploid fibroblasts to intermittent ELF electromagnetic fields. DNA damage was measured using alkaline and neutral comet assays. Exposure at 50 Hz sinusoidal, 1-24 h, 20-1,000 mu T, with a 5 min on/10 min off pattern induced dose-dependent and time-dependent DNA single-strand and double-strand breaks. Effects were observed at magnetic flux densities as low as 35 mu T, well below ICNIRP guidelines. The induced comet tail factors returned to normal within 9 h after exposure ended.
Unknown authors · 2003
Researchers conducted a population-based case-control study of 491 children with acute lymphoblastic leukemia and 491 matched controls in Québec. Maternal occupational ELF-MF exposure during pregnancy was estimated from prenatal occupational history using three metrics. Comparing the highest 10% of exposed mothers to others, leukemia risk was moderately increased across all metrics. The highest odds ratio was 2.5 (95% confidence interval = 1.2-5.0) for maximum exposure of 0.4 microtesla or more.
Unknown authors · 2003
The study examined a cohort of 537,692 men and 180,529 women in the Swedish engineering industry. Exposure to extremely low-frequency magnetic fields was assessed using a job exposure matrix with four levels. Alzheimer's disease risk increased with exposure, reaching a relative risk of 4.0 (95% CI 1.4-11.7) in the highest exposure group. ALS showed a relative risk of 2.2 (95% CI 1.0-4.7) in the highest exposure group with a suggested exposure-response relationship. No increased risk was found for Parkinson's disease or multiple sclerosis.
Unknown authors · 2003
The study included all economically active individuals in the Swedish 1980 census (4,812,646 subjects) and followed them for neurodegenerative disease mortality from 1981 through 1995. A job-exposure matrix based on magnetic field measurements was used to assess EMF exposure. Men exposed in both 1970 and 1980 had an increased Alzheimer's disease mortality risk (relative risk 2.3 for exposure >/=0.5 microT). The association was strongest for early-onset Alzheimer's disease or with 10-year follow-up after last occupation. Amyotrophic lateral sclerosis was not linked to EMF exposure, but electrical and electronics work showed a risk estimate of 1.4.
Unknown authors · 2003
