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Karipidis K, Mate R, Urban D, Tinker R, Wood A. 5G mobile networks and health-a state-of-the-science review of the research into low-level RF fields above 6 GHz. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2021; 31:585-605. [PMID: 33727687 PMCID: PMC8263336 DOI: 10.1038/s41370-021-00297-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 12/23/2020] [Accepted: 01/21/2021] [Indexed: 05/27/2023]
Abstract
The increased use of radiofrequency (RF) fields above 6 GHz, particularly for the 5 G mobile phone network, has given rise to public concern about any possible adverse effects to human health. Public exposure to RF fields from 5 G and other sources is below the human exposure limits specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). This state-of-the science review examined the research into the biological and health effects of RF fields above 6 GHz at exposure levels below the ICNIRP occupational limits. The review included 107 experimental studies that investigated various bioeffects including genotoxicity, cell proliferation, gene expression, cell signalling, membrane function and other effects. Reported bioeffects were generally not independently replicated and the majority of the studies employed low quality methods of exposure assessment and control. Effects due to heating from high RF energy deposition cannot be excluded from many of the results. The review also included 31 epidemiological studies that investigated exposure to radar, which uses RF fields above 6 GHz similar to 5 G. The epidemiological studies showed little evidence of health effects including cancer at different sites, effects on reproduction and other diseases. This review showed no confirmed evidence that low-level RF fields above 6 GHz such as those used by the 5 G network are hazardous to human health. Future experimental studies should improve the experimental design with particular attention to dosimetry and temperature control. Future epidemiological studies should continue to monitor long-term health effects in the population related to wireless telecommunications.
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Affiliation(s)
- Ken Karipidis
- Australian Radiation Protection and Nuclear Safety Agency, Melbourne, VIC, Australia.
| | - Rohan Mate
- Australian Radiation Protection and Nuclear Safety Agency, Melbourne, VIC, Australia
| | - David Urban
- Australian Radiation Protection and Nuclear Safety Agency, Melbourne, VIC, Australia
| | - Rick Tinker
- Australian Radiation Protection and Nuclear Safety Agency, Melbourne, VIC, Australia
| | - Andrew Wood
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia
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Koyama S, Narita E, Suzuki Y, Shiina T, Taki M, Shinohara N, Miyakoshi J. Long-term exposure to a 40-GHz electromagnetic field does not affect genotoxicity or heat shock protein expression in HCE-T or SRA01/04 cells. JOURNAL OF RADIATION RESEARCH 2019; 60:417-423. [PMID: 31197350 PMCID: PMC6640906 DOI: 10.1093/jrr/rrz017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 12/17/2018] [Indexed: 05/31/2023]
Abstract
Millimeter waves are used in various fields, and the risks of this wavelength range for human health must be carefully evaluated. In this study, we investigated the effects of millimeter waves on genotoxicity and heat shock protein expression in human corneal epithelial (HCE-T) and human lens epithelial (SRA01/04) cells. We exposed the cells to 40-GHz millimeter waves at 1 mW/cm2 for 24 h. We observed no statistically significant increase in the micronucleus (MN) frequency or the level of DNA strand breaks in cells exposed to 40-GHz millimeter waves relative to sham-exposed and incubator controls. Heat shock protein (Hsp) expression also exhibited no statistically significant response to the 40-GHz exposure. These results indicate that exposure to 40 GHz millimeter waves under these conditions has little or no effect on MN formation, DNA strand breaks, or Hsp expression in HCE-T or SRA01/04 cells.
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Affiliation(s)
- Shin Koyama
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto, Japan
| | - Eijiro Narita
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto, Japan
| | - Yukihisa Suzuki
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo, Japan
| | - Takeo Shiina
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo, Japan
| | - Masao Taki
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo, Japan
| | - Naoki Shinohara
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto, Japan
| | - Junji Miyakoshi
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto, Japan
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Koyama S, Narita E, Shimizu Y, Suzuki Y, Shiina T, Taki M, Shinohara N, Miyakoshi J. Effects of Long-Term Exposure to 60 GHz Millimeter-Wavelength Radiation on the Genotoxicity and Heat Shock Protein (Hsp) Expression of Cells Derived from Human Eye. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13080802. [PMID: 27509516 PMCID: PMC4997488 DOI: 10.3390/ijerph13080802] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/26/2016] [Accepted: 08/04/2016] [Indexed: 11/16/2022]
Abstract
Human corneal epithelial (HCE-T) and human lens epithelial (SRA01/04) cells derived from the human eye were exposed to 60 gigahertz (GHz) millimeter-wavelength radiation for 24 h. There was no statistically significant increase in the micronucleus (MN) frequency in cells exposed to 60 GHz millimeter-wavelength radiation at 1 mW/cm² compared with sham-exposed controls and incubator controls. The MN frequency of cells treated with bleomycin for 1 h provided positive controls. The comet assay, used to detect DNA strand breaks, and heat shock protein (Hsp) expression also showed no statistically significant effects of exposure. These results indicate that exposure to millimeter-wavelength radiation has no effect on genotoxicity in human eye cells.
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Affiliation(s)
- Shin Koyama
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Eijiro Narita
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Yoko Shimizu
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Yukihisa Suzuki
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo 192-0397, Japan.
| | - Takeo Shiina
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo 192-0397, Japan.
| | - Masao Taki
- Department of Electrical & Electronic Engineering, Graduate Schools of Science and Engineering, Tokyo Metropolitan University, 1-1, Hachioji, Tokyo 192-0397, Japan.
| | - Naoki Shinohara
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Junji Miyakoshi
- Laboratory of Applied Radio Engineering for Humanosphere, Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan.
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Beneduci A, Cosentino K, Romeo S, Massa R, Chidichimo G. Effect of millimetre waves on phosphatidylcholine membrane models: a non-thermal mechanism of interaction. SOFT MATTER 2014; 10:5559-5567. [PMID: 24959858 DOI: 10.1039/c4sm00551a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The nonthermal biological effects of millimeter waves have been mainly attributed to the interaction with biological membranes. Several data on biomimetic membrane systems seem to support this conclusion. In this paper a mechanistic hypothesis is evaluated to explain such an interaction taking into account experimental NMR data on deuterium-labeled phospholipid vesicles. These data showed that millimeter waves induce a time and a hydration-dependent reduction of the water ordering around the phosphocholine headgroups. This effect is here interpreted as a change in membrane water partitioning, due to the coupling of the radiation with the fast rotational dynamics of bound water molecules, that results in a measurable relocation of water molecules from the inner to the outer binding regions of the membrane interface. When millimeter wave exposure is performed in the vicinity of the transition point, this effect can lead to an upward shift of the membrane phase transition temperature from the fluid to the gel phase. At a macroscopic level, this unique sensitivity may be explained by the universal dynamic behaviour of the membranes in the vicinity of the transition point, where a pretransitional increase of membrane area fluctuations, i.e., of the mean area per phospholipid headgroup, is observed. Exposure to millimeter waves increases the above fluctuations and enhances the second order character of the transition.
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Affiliation(s)
- Amerigo Beneduci
- Department of Chemistry and Chemical Technologies, University of Calabria, Arcavacata di Rende (CS), Italy.
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Cohen I, Cahan R, Shani G, Cohen E, Abramovich A. Effect of 99 GHz continuous millimeter wave electro-magnetic radiation onE. coliviability and metabolic activity. Int J Radiat Biol 2010; 86:390-9. [DOI: 10.3109/09553000903567912] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Pakhomov AG, Prol HK, Mathur SP, Akyel Y, Campbell CBG. Frequency-Specific Effects of Millimeter-Wavelength Electromagnetic Radiation in Isolated Nerve. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/15368379709016172] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Jelínek F, Pokorný J, Šaroch J, Hašek J. Experimental Investigation of Electromagnetic Activity of Yeast Cells at Millimeter Waves. Electromagn Biol Med 2009. [DOI: 10.1080/15368370500379749] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Logani MK, Bhanushali A, Ziskin MC, Prihoda TJ. Micronuclei in Peripheral Blood and Bone Marrow Cells of Mice Exposed to 42 GHz Electromagnetic Millimeter Waves. Radiat Res 2004; 161:341-5. [PMID: 14982479 DOI: 10.1667/rr3121] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The genotoxic potential of 42.2 +/- 0.2 GHz electromagnetic millimeter-wave radiation was investigated in adult male BALB/c mice. The radiation was applied to the nasal region of the mice for 30 min/day for 3 consecutive days. The incident power density used was 31.5 +/- 5.0 mW/cm2. The peak specific absorption rate was calculated as 622 +/- 100 W/kg. Groups of mice that were injected with cyclophosphamide (15 mg/kg body weight), a drug used in the treatment of human malignancies, were also included to determine if millimeter-wave radiation exposure had any influence on drug-induced genotoxicity. Concurrent sham-exposed and untreated mice were used as controls. The extent of genotoxicity was assessed from the incidence of micronuclei in polychromatic erythrocytes of peripheral blood and bone marrow cells collected 24 h after treatment. The results indicated that the incidence of micronuclei in 2000 polychromatic erythrocytes was not significantly different among untreated, millimeter wave-exposed, and sham-exposed mice. The group mean incidences were 6.0 +/- 1.6, 5.1 +/- 1.5 and 5.1 +/- 1.3 in peripheral blood and 9.1 +/- 1.1, 9.3 +/- 1.6 and 9.1 +/- 1.6 in bone marrow cells, respectively. Mice that were injected with cyclophosphamide exhibited significantly increased numbers of micronuclei, 14.6 +/- 2.7 in peripheral blood and 21.3 +/- 3.9 in bone marrow cells (P< 0.0001). The drug-induced micronuclei were not significantly different in millimeter wave-exposed and sham-exposed mice; the mean incidences were 14.3 +/- 2.8 and 15.4 +/- 3.0 in peripheral blood and 23.5 +/- 2.3 and 22.1 +/- 2.5 in bone marrow cells, respectively. Thus there was no evidence for the induction of genotoxicity in the peripheral blood and bone marrow cells of mice exposed to electromagnetic millimeter-wave radiation. Also, millimeter-wave radiation exposure did not influence cyclophosphamide-induced micronuclei in either type of cells.
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Szabo I, Rojavin MA, Rogers TJ, Ziskin MC. Reactions of keratinocytes to in vitro millimeter wave exposure. Bioelectromagnetics 2001; 22:358-64. [PMID: 11424160 DOI: 10.1002/bem.62] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The effects of millimeter waves (MW) on human keratinocytes were studied in vitro using the HaCaT keratinocyte cell line. MW-induced modulation of keratinocyte function was studied in proliferation, adhesion, chemotaxis, and interleukin-1beta (IL-1beta) production assays. Spontaneous proliferation, adhesion to tissue culture plate, random migration, and IL-8- and RANTES induced chemotaxis were not affected by exposure of cells to millimeter waves under the following conditions: frequency, 61.22 GHz; SAR, 770 W/kg; duration of exposure, 15-30 min. However, MW irradiation resulted in a modest but statistically significant increase in the intracellular level of IL-1beta. These data suggest that exposure of human skin (with keratinocytes being the major component of epidermis) to MW can cause activation of basal keratinocytes resulting in an elevated level of IL-1beta production.
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Affiliation(s)
- I Szabo
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA
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Alekseev SI, Ziskin MC. Millimeter wave power density in aqueous biological samples. Bioelectromagnetics 2001; 22:288-91. [PMID: 11298391 DOI: 10.1002/bem.52] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Power density distribution inside a water sample placed between two parallel lossy dielectric plates (Polystyrene) was calculated using Fresnel equations for the frequency range of 42.25-53.57 GHz. Due to the multiple internal reflections from the sample boundaries, the distribution of the power density within the thin sample is more uniform than that within a semi-infinite medium. The power density in a sample depends on the thicknesses of the sample and the adjacent dielectric plates. For the given frequency range the sample thickness optimal for power density uniformity varies between 0.28 and 0.33 mm. The front plate has a significant effect on the magnitude of the power density within the sample but little effect on the power density distribution. The thicker the rear plate, the greater is the non uniformity of the power density distribution within the sample. Based on the calculated data, we determined the dimension of an exposure chamber providing the optimal power density distribution uniformity for mm-wave irradiation.
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Affiliation(s)
- S I Alekseev
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region 142292, Russia
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11
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Pakhomov AG, Prol HK, Mathur SP, Akyel Y, Campbell CB. Search for frequency-specific effects of millimeter-wave radiation on isolated nerve function. Bioelectromagnetics 2000; 18:324-34. [PMID: 9140663 DOI: 10.1002/(sici)1521-186x(1997)18:4<324::aid-bem5>3.0.co;2-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Effects of a short-term exposure to millimeter waves (CW, 40-52 GHz, 0.24-3.0 mW/cm2) on the compound action potential (CAP) conduction were studied in an isolated frog sciatic nerve preparation. CAPs were evoked by either a low-rate or a high-rate electrical stimulation of the nerve (4 and 20 paired pulses/s, respectively). The low-rate stimulation did not alter the functional state of the nerve, and the amplitude, latency, and peak latency of CAPs could stay virtually stable for hours. Microwave irradiation for 10-60 min at 0.24-1.5 mW/cm2, either at various constant frequencies or with a stepwise frequency change (0.1 or 0.01 GHz/min), did not cause any detectable changes in CAP conduction or nerve refractoriness. The effect observed under irradiation at a higher field intensity of 2-3 mW/cm2 was a subtle and transient reduction of CAP latency and peak latency along with a rise of the test CAP amplitude. These changes could be evoked by any tested frequency of the radiation; they reversed shortly after cessation of exposure and were both qualitatively and quantitatively similar to the effect of conventional heating of 0.3-0.4 degree C. The high-rate electrical stimulation caused gradual and reversible decrease of the amplitude of conditioning and test CAPs and increased their latencies and peak latencies. These changes were essentially the same with and without irradiation (2.0-2.7 or 0.24-0.28 mW/cm2), except for attenuation of the decrease of the test CAP amplitude. This effect was observed at both field intensities, but was statistically significant only for certain frequencies of the radiation. Within the studied limits, this effect appeared to be dependent on the frequency rather than on the intensity of the radiation, but this observation requires additional experimental confirmation.
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Affiliation(s)
- A G Pakhomov
- Microwave Bioeffects Branch, U.S. Army Medical Research Detachment of the Walter Reed Army Institute of Research, Brooks Air Force Base, San Antonio, Texas 78235-5324, USA
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12
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Abstract
Reflection, transmission, and absorption of mm-waves by thin absorbing films were determined at two therapeutic frequencies: 42. 25 and 53.57 GHz. Thin filter strips saturated with distilled water or an alcohol-water solution were used as absorbing samples of different thicknesses. The dependence of the power reflection coefficient R(d) on film thickness (d) was not monotonic. R(d) passed through a pronounced maximum before reaching its steady-state level [R(infinity)]. Similarly, absorption, A(d), passed two maximums with one minimum between them, before reaching its steady-state level [A(infinity)]. At 42.25 GHz, A(d) was compared with absorption in a semi-infinite water medium at a depth d. When d < 0.3 mm, absorption by the film increased: at d = 0.1 mm the absorption ratio for the thin layer sample and the semi-infinite medium was 3.2, while at d = 0.05 mm it increased up to 5.8. Calculations based on Fresnel equations for flat thin layers adequately described the dependence of the reflection, transmission, and absorption on d and allowed the determination of the refractive index (n), dielectric constant (epsilon), and penetration depth (delta) of the absorbing medium for various frequencies. For water samples, epsilon was found to be 12.4-19.3j, delta = 0.49 mm at 42.25 GHz, and epsilon = 9.0-19.5j, delta = 0.36 mm at 53.57 GHz. The calculated power density distribution within the film was strongly dependent on d. The measurements and calculations have shown that the reflection and absorption of mm-waves by thin absorbing layers can significantly differ from the reflection and absorption in similar semi-infinite media. The difference in reflection, absorption, and power density distribution in films, as compared to semi-infinite media, are caused by multiple internal reflections from the film boundaries. That is why, when using thin phantoms and thin biological samples, the specifics of the interaction of mm-waves with thin films should be taken into account.
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Affiliation(s)
- S I Alekseev
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, Russia
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Radzievsky AA, Rojavin MA, Cowan A, Alekseev SI, Ziskin MC. Hypoalgesic effect of millimeter waves in mice: dependence on the site of exposure. Life Sci 2000; 66:2101-11. [PMID: 10823349 DOI: 10.1016/s0024-3205(00)00536-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Based on a hypothesis of neural system involvement in the initial absorption and further processing of the millimeter electromagnetic waves (MW) signal, we reproduced, quantitatively assessed and compared the analgesic effect of a single MW treatment, exposing areas of skin possessing different innervation densities. The cold water tail flick test (cTFT) was used to assess experimental pain in mice. Three areas of exposure were used: the nose, the glabrous skin of the right footpad, and the hairy skin of the mid back at the level of T5-T10. The MW exposure characteristics were: frequency = 61.22 GHz; incident power density = 15mW/cm2; and duration = 15 min. The maximum hypoalgesic effect was achieved by exposing to MW the more densely innervated skin areas--the nose and the footpad. The hypoalgesic effect in the cTFT after MW exposure to the murine back, which is less densely innervated, was not statistically significant. These results support the hypothesis of neural system involvement in the systemic response to MW.
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Affiliation(s)
- A A Radzievsky
- Center for Biomedical Physics, Temple University School of Medicine, Philadelphia, PA 19140, USA.
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Gandhi OP. d'Arsonval Medal: address. some bioelectromagnetics research at the University of Utah: acceptance speech on the occasion of receiving the d'Arsonval Medal. Bioelectromagnetics 1996; 17:3-9. [PMID: 8742750 DOI: 10.1002/(sici)1521-186x(1996)17:1<3::aid-bem1>3.0.co;2-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- O P Gandhi
- Department of Electrical Engineering, University of Utah, Salt Lake City, USA
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15
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Steel MC, Sheppard RJ. The dielectric properties of rabbit tissue, pure water and various liquids suitable for tissue phantoms at 35 GHz. Phys Med Biol 1988; 33:467-72. [PMID: 3380886 DOI: 10.1088/0031-9155/33/4/006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Newly developed microwave apparatus was used to measure the complex permittivity of some rabbit tissues and water over the temperature range 20-37 degrees C. Various liquid mixtures which might be suitable as phantom tissue equivalents at 35 GHz were also considered. Some of the measured tissue data were compared with previous lower frequency data and it was concluded that the observed behaviour was not anomalous.
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Affiliation(s)
- M C Steel
- Department of Physics, King's College, Strand, London, UK
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Gandhi OP. Some basic properties of biological tissues for potential biomedical applications of millimeter waves. THE JOURNAL OF MICROWAVE POWER 1983; 18:295-304. [PMID: 6197526 DOI: 10.1080/16070658.1983.11689334] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The paper gives the highlights of the reports in the literature on sharp, distinct resonances in the absorption and action spectra at millimeter wavelengths of various biochemicals, and bacteriological and biological preparations. If true, these properties may be employed for in-vitro diagnostic applications and form a basis for frequency-specific health hazards and for new forms of cancer therapy. Carefully performed experiments in our laboratory have failed to reveal frequency-specific biological effects on BHK-21/C13 mammalian cells, on induction of lambda prophages in lysogenic Escherichia coli and on back-mutation of His Salmonella typhimurium cells. Also on account of the high absorbance of water (13--36 dB/mm) which is an essential part of living tissues, little or no differences have been observed for the absorption spectra biological samples in the 26.5 to 90.0 GHz band. Dielectric characterization of the biological samples is needed and may form a basis for broadband differences in the millimeter wave absorption by various tissues.
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Swicord ML, Davis CC. An optical method for investigating the microwave absorption characteristics of DNA and other biomolecules in solution. Bioelectromagnetics 1983; 4:21-42. [PMID: 6340696 DOI: 10.1002/bem.2250040104] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Direct determination of the microwave absorption characteristics of biological molecules in solution by an optical heterodyne technique is described. A visibly transparent sample is irradiated in a spatially nonuniform manner with pulsed microwaves, and the spatial variation in temperature increase measured by detecting the phase chirp impressed on a single-frequency He-Ne laser beam passing through the heated region. Results for several liquids and solutions such as water, methanol, various saline solutions, and solutions of DNA and DNA sodium salt in water are described. Where direct comparison is possible the results agree very well with published values. A significant increase in the absorption of DNA solutions compared with pure water has been observed that is consistent with microwave absorption by the longitudinal mode of the double helix.
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Gandhi OP. Electromagnetic absorption in an inhomogeneous model of man for realistic exposure conditions. Bioelectromagnetics 1982; 3:81-90. [PMID: 7082394 DOI: 10.1002/bem.2250030112] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The advances made in quantifying electromagnetic absorption and its distribution for various exposure profiles are described. The conditions that have been studied extensively are: free-space irradiation and its variations, such as the presence of ground and reflecting surfaces and other humans in close proximity. Using an inhomogeneous block model of man, work has recently been extended to leakage-type near-fields such as those from RF heat sealers and other electronic equipment. Projections are made for the extension of this work to evaluate coupled near-fields, design of multielement near-field applicators to obtain physician-prescribed uniform or nonuniform rates of regional heating, and for the inverse scattering problem necessary for electromagnetic biomedical imaging. Accurate information about the dielectric properties of various tissues becomes increasingly important for proper inhomogeneous modeling of man.
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