Chou CK, McDougall JA, Can KW · 1995
Researchers tested the possibility of tissue heating from an auditory brainstem implant and a modified cochlear implant during MRI using a full-sized human phantom with simulated skull, brain, and muscle. Thermograms were taken before and after a 26-minute MRI scan with 94 excitations and 25 ms echo time set to induce maximum radiofrequency heating. Results showed no observable heating associated with either implant during worst-case MRI of the head.
Reiser H, Dimpfel W, Schober F · 1995
Researchers conducted a single-blind, cross-over, placebo-controlled study with 36 volunteers. Volunteers were exposed to a MEGA-WAVE therapy instrument and a mobile digital telephone, and also underwent a no-exposure control. The MEGA-WAVE instrument increased EEG power in Alpha2, Beta1, and Beta2 bands during and after exposure. The mobile telephone increased EEG power in the same bands after a delay of about 15 minutes.
Grigor'ev IuG, Luk'ianova SN, Makarov VP, Rynskov VV · 1995
Researchers exposed thirty rabbits to thirty-minute microwave irradiation at 1.5 GHz with a pulse intensity of 0.3 mW/cm2 and tested several pulsed modes. A reliable effect was detected only in the hippocampus, shown as an amplification of theta-range activity within normal functioning. The total bioelectrical activity of the cortex, caudate nucleus, hypothalamus, amygdala, and septum was not reliably changed.
Unknown authors · 1994
Researchers conducted an open-field provocation in front of an ordinary TV set with two patients who regarded themselves as suffering from skin problems due to work at video display terminals. Before the provocation, skin biopsies from the anterior neck showed a high-to-very high number of somatostatin-immunoreactive dendritic cells and histamine-positive mast cells. At the end of the provocation, the number of mast cells was unchanged, but the somatostatin-positive cells had seemingly disappeared. The researchers noted that the high number of mast cells may explain the clinical symptoms of itch, pain, edema and erythema.
Unknown authors · 1994
Researchers measured magnetic fields and depression symptoms in 152 women living near or one block from transmission lines. Average magnetic field was 4.86 mG at adjacent homes and 0.68 mG at homes one block away.
Unknown authors · 1994
Researchers analyzed data from the Vietnam Experience Study to assess the association between electric and magnetic field exposure and depression. They classified employed participants as electrical workers (N = 183) and nonelectrical workers (N = 3,861) and compared their scores on the Diagnostic Interview Survey and the Minnesota Multiphasic Personality Inventory. Electrical workers in the aggregate showed little evidence of increased risk, with the possible exception of an increase in elevated MMPI depression scores among short-term workers. Data on electricians yielded indications of increased risk for several markers of depression.
Unknown authors · 1994
Researchers conducted a case-control study of adults who lived between 1960 and 1985 on properties in Sweden within 300 meters of 220 or 400 kilovolt power lines. The study identified 325 leukemia cases and 223 central nervous system tumor cases, with two matched controls per case. Exposure was assessed by spot measurements and by calculations of the magnetic fields generated by the power lines. For calculated magnetic field levels of 0.2 microT or more, the relative risk was 1.7 for acute myeloid leukemia and 1.7 for chronic myeloid leukemia; using cumulative exposure for 15 years the relative risks were 2.3 and 2.1 for the highest exposure category.
Unknown authors · 1994
A case-control study with 12 cases and 48 matched controls examined risk factors including distance to low frequency radio towers. The odds ratio for having lived within 2.6 miles of the radio towers before diagnosis was 2.0 with a 95% confidence interval of 0.06 to 8.3. The authors noted the clustering may have been a chance event but should be noted due to its peculiar characteristics.
Libertin CR et al. · 1994
Researchers used HeLa cells with a CAT reporter driven by the HIV LTR to test the effects of various radiations. Ultraviolet light increased HIV-LTR-driven transcription. Gamma rays, limited sunlight, and electromagnetic fields did not significantly affect transcription. Microwaves did not alter expression unless heating occurred, in which case transcription was induced.
Lu Y, Yu J, Ren Y · 1994
Researchers measured dielectric properties of human red blood cells in suspension at 25 degrees C across 1-500 MHz using a coaxial transmission line reflection method. The study included 243 healthy persons with a hematocrit of 50%. The data revealed a statistically significant age dependence with a critical age of about 49 years, above which permittivity and conductivity decreased significantly.
Thuroczy G, Kubinyi G, Bodo M, Bakos J, Szabo LD, · 1994
At 30 mW/cm², total EEG power increased, while at 10 mW/cm² EEG did not change but cerebral blood flow increased. Brain-localized 4 GHz continuous-wave exposure at 42 mW/g SAR increased EEG delta power and REG amplitude simultaneously.
Salford LG, Brun A, Sturesson K, Eberhardt JL, Persson BRq · 1994
Researchers exposed male and female Fischer 344 rats to 915 MHz microwaves as continuous wave and pulse-modulated at 8, 16, 50, and 200 Hz in a transverse electromagnetic transmission line chamber. Albumin leakage occurred in 56 of 184 exposed rats versus 5 of 62 controls, and continuous wave exposure yielded 14 positive findings out of 35 that were significantly different from controls (P = 0.002). The specific energy absorption rate varied between 0.016 and 5 W/kg, and rats were exposed for 2 hours without anesthesia.
Mickley GA, Cobb BL, Mason PA, Farrell S · 1994
Researchers exposed rats to various doses of microwave radiation between training and testing to study effects on working memory. Memory was assessed by measuring relative exploration time of a familiar versus a new object, with extensive re-exploration of the familiar object indicating memory loss. Rats exposed to more than 5 W/kg developed hyperthermia, and microwave-exposed rats at doses of 1, 5, 8.5, 9.3, and 10 W/kg did not show a preference for the new object, unlike normothermic controls. Microwave hyperthermia evoked prominent c-fos expression in periventricular strata, hypothalamic nuclei, amygdala, and several cortical areas.
Dimbylow PJ, Mann SM. · 1994
Researchers built a mathematical model of the human head from MRI slices and used finite-difference time-domain (FDTD) calculations to estimate the specific energy absorption rate (SAR) at 900 MHz and 1.8 GHz. The generic transceiver was represented by a quarter-wavelength monopole on a metal box, and three placement geometries were examined: vertical in front of the eye, and vertical and horizontal at the side of the ear. For the most typical position at the side of the head, the maximum SAR averaged over 10 g of tissue was 2.1 and 3.0 W kg(-1) per W of radiated power at 900 MHz and 1.8 GHz. Placement in front of the eye gave values of 3.1 and 4.6 W kg(-1) per W averaged over 10 g of tissue at 900 MHz and 1.8 GHz.
Unknown authors · 1993
Researchers conducted a telephone interview survey in November 1987 to assess depressive symptoms and headaches in relation to proximity to an alternating-current transmission line. Proximity was defined as residing on a property abutting the right-of-way or being able to see the towers from one's house or yard. Proximity was positively associated with depressive symptoms with an odds ratio of 2.8 (95% CI 1.6-5.1). The association was not explained by demographic variables associated with depression or by attitudes about power lines or other environmental issues. Nonmigraine headaches had a weaker association with proximity (odds ratio = 1.5, 95% CI 0.76-2.8) and self-reported migraine headaches exhibited no association (odds ratio = 0.99, 95% CI 0.29-3.4).
Unknown authors · 1993
A case-control study examined cancer incidence in children who lived within 300 meters of 220 and 400 kV power lines in Sweden from 1960 to 1985. Researchers identified 142 cancer cases, including 39 leukemia and 33 central nervous system tumor cases, and selected 558 controls from the study base. For childhood leukemia, the relative risk was 2.7 (95% CI 1.0-6.3) at 0.2 microtesla and 3.8 (95% CI 1.4-9.3) at 0.3 microtesla, with significant trends. No association was found for central nervous system tumors, lymphoma, or all childhood cancers combined.
Unknown authors · 1993
Researchers simulated cohort and case-control samples using ELF-MF exposure prevalence, childhood leukemia incidence, and confounder data from literature and existing datasets. They combined the simulated data using three methods: two-stage meta-analysis, one-stage pooling, and two-stage meta-analysis with pooling. All three methods produced estimates close to the causal estimate with no obvious overestimation or underestimation. One-stage pooling showed the widest confidence intervals but the difference was not statistically significant.
Unknown authors · 1993
Researchers simulated cohort and case-control samples using parameters from literature and existing datasets to test pooling methods for different study designs. They combined the simulated data using two-stage meta-analysis, one-stage pooling, and two-stage meta-analysis with pooling. All three methods yielded estimates close to the causal estimate with no obvious overestimation or underestimation. One-stage pooling showed the widest 95% confidence interval but the difference was not significant. The authors concluded that the performance of the three methods was not certain and further simulations are needed.
Unknown authors · 1993
Researchers observed six incident cases of testicular cancer among 340 police officers between 1979 and 1991. The observed-to-expected ratio was 6.9 with p<0.001. All six officers routinely held hand-held radar guns close to their testicles.
Ulashchik VS · 1993
The study aimed to investigate changes in drug pharmacokinetics and pharmacodynamics under the influence of microwaves of different ranges. Human and animal experiments were conducted to compare the effect of microwaves of different ranges on drug pharmacodynamics and pharmacokinetics. The results suggested that microwaves could potentiate and prolong the action of some drugs.
Leitgeb N, Tropper K · 1993
Researchers investigated a worst-case scenario where a child observes the microwave oven interior with eyes as close to the door as possible. Significant microwave heating occurred only when safety contacts were inactivated and the door was opened. At a 2.3 cm door gap, microwaves contributed no more than 16% of a 5°C temperature rise after one hour, and at a 2.6 cm gap they contributed 50% of a 2°C rise after 15 minutes.
Ouellet-Hellstrom R, Stewart WF · 1993
Researchers mailed questionnaires to 42,403 physical therapists in 1989 and used a nested case-control design with 1,753 miscarriage cases matched to 1,753 controls. A pregnancy was considered exposed if the mother reported using microwave or shortwave diathermy in the six months before or during the first trimester. Microwave use was associated with increased miscarriage odds (OR 1.28, 95% CI 1.02-1.59) with a dose-response trend, while shortwave diathermy was not associated (OR 1.07, 95% CI 0.91-1.24).
Maes A, Verschaeve L, Arroyo A, De Wagter C, Vercruyssen L · 1993
Researchers exposed human peripheral blood lymphocytes to 2450 MHz microwaves for 30 and 120 minutes at constant body temperature. Exposure caused a marked increase in chromosome aberrations, including dicentric chromosomes and acentric fragments, and micronuclei. Microwave exposure did not influence cell kinetics or sister chromatid exchange frequency.
Unknown authors · 1992
The study used an ultrasensitive superconducting magnetometer to detect ferromagnetic material in various human brain tissues. High-resolution electron microscopy identified the minerals as belonging to the magnetite-maghemite family, with crystal morphologies resembling those produced by magnetotactic bacteria and fish. The measurements imply at least 5 million single-domain crystals per gram in most brain tissues and over 100 million per gram in the pia and dura.
Fucic A, Garaj-Vrhovac V, Skara M, Dimitrovic B · 1992
Researchers used the micronucleus assay with a new mathematical approach to separate clastogenic from aneugenic activity of vinyl chloride monomer, X-rays, and microwaves on human somatic cells. Comparison of micronucleus size distributions in lymphocytes from exposed humans showed X-rays and microwaves were preferentially clastogens while vinyl chloride monomer showed aneugenic activity as well. The authors noted that microwaves possess some mutagenic characteristics typical of chemical mutagens.
