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Brink WM, Remis RF, Webb AG. Radiofrequency safety of high permittivity pads in MRI-Impact of insulation material. Magn Reson Med 2023; 89:2109-2116. [PMID: 36708148 DOI: 10.1002/mrm.29580] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/30/2022] [Accepted: 12/26/2022] [Indexed: 01/29/2023]
Abstract
PURPOSE High permittivity dielectric pads are known to be effective for tailoring the RF field and improving image quality in high field MRI. Despite a number of studies reporting benign specific absorption rate (SAR) effects, their "universal" safety remains an open concern. In this work, we evaluate the impact of the insulation material in between the pad and the body, using both RF simulations as well as phantom experiments. METHODS A 3T configuration with high permittivity material was simulated and characterized experimentally in terms of B1 + fields and RF power absorption, both with and without electrical insulation in between the high permittivity material and the sample. Different insulation conditions were compared, and electromagnetic analyses on the induced current density were performed to elucidate the effect. RESULTS Increases in RF heating of up to 49% were observed experimentally in a tissue-mimicking phantom after removing the material insulation. The B1 + magnitude and RF transceive phase were not affected. Simulations indicated that an insulation thickness of 0.5-2 mm should be accounted for in numerical models in order to ensure reliable results. CONCLUSION A reliable RF safety assessment of high permittivity dielectric pads requires accounting for the insulating properties of the plastic encasing. Ignoring the electrical insulation can lead to erroneous results with substantial increases in local SAR at the interface. Conversely, the material insulation does not need to be modeled to predict the B1 + effects during the design of the pad geometry.
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Affiliation(s)
- Wyger M Brink
- C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.,Magnetic Detection & Imaging Group, TechMed Centre, University of Twente, Enschede, The Netherlands
| | - Rob F Remis
- Circuits and Systems Group, Department of Microelectronics, Delft University of Technology, Delft, The Netherlands
| | - Andrew G Webb
- C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
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2
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Foster KR. The need for consensus guidelines to address the mixed legacy of genetic damage assessments for radiofrequency fields. Int J Radiat Biol 2023:1-11. [PMID: 37036431 DOI: 10.1080/09553002.2023.2188936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
PURPOSE This review considers issues related to interpreting the mixed legacy of >300 papers published during the past three decades on possible genotoxic effects of exposure of human and animal tissues to radiofrequency electromagnetic fields (RF-EMF). The main paper reviews the evolution of consensus guidelines for genotoxicity testing and the increasing emphasis on systematic reviews for evaluation of scientific studies for use in health risk assessments. An Appendix considers some issues in assessing the bioeffects literature by examining a subset of genotoxicity publications that employed the comet assay. While most studies found no statistically significant effects of exposure, a significant minority of studies (chiefly, in vivo studies) reported statistically significant effects of exposure. The quality of the studies was highly variable; while several studies were meticulously done and documented, none of these studies were compliant with currently accepted guidelines such as those of the Organization for Economic Cooperation and Development (OECD). Evaluation of the studies using risk of bias (RoB) criteria showed that, in this sample of studies, higher quality studies were less likely to find statistically significant results than those of lower quality. CONCLUSION The authors conclude that statistical significance should be only one consideration in evaluation of bioeffects studies. Simply listing 'statistically' significant effects identified using null hypothesis testing and the criterion p < 0.05 for statistical significance is misleading and uninformative in assessing health risks of exposure. A careful synthesis of evidence is needed, including assessment of study validity, biological significance of reported effects, and coherence of study results with those of other related studies.The authors recommend that all future RF genotoxicity studies intended for use in human health risk assessments and evaluations of the literature should be done in compliance with accepted quality guidelines, i.e. OECD or equivalent guidelines for genotoxicity screening studies and PRISMA or other accepted guideline for reviews of the literature. The positive studies in this group should be redone with tighter quality control to establish the reliability of the findings.
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Affiliation(s)
- Kenneth R Foster
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
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3
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Romeo S, Zeni O, Scarfì MR, Poeta L, Lioi MB, Sannino A. Radiofrequency Electromagnetic Field Exposure and Apoptosis: A Scoping Review of In Vitro Studies on Mammalian Cells. Int J Mol Sci 2022; 23:2322. [PMID: 35216437 DOI: 10.3390/ijms23042322] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 02/01/2023] Open
Abstract
In the last decades, experimental studies have been carried out to investigate the effects of radiofrequency (RF, 100 kHz–300 GHz) electromagnetic fields (EMF) exposure on the apoptotic process. As evidence-based critical evaluation of RF and apoptosis in vitro is lacking, we performed a scoping literature review with the aim of systematically mapping the research performed in this area and identifying gaps in knowledge. Eligible for inclusion were in vitro studies assessing apoptosis in mammalian cells exposed to RF-EMF, which met basic quality criteria (sham control, at least three independent experiments, appropriate dosimetry analysis and temperature monitoring). We conducted a systematic literature review and charted data in order to overview the main characteristics of included studies. From the 4362 papers retrieved with our search strategy, 121 were pertinent but, among them, only 42 met basic quality criteria. We pooled data with respect to exposure (frequency, exposure level and duration) and biological parameters (cell type, endpoint), and highlighted some qualitative trends with respect to the detection of significant effect of RF-EMF on the apoptotic process. We provided a qualitative picture of the evidence accumulated so far, and highlighted that the quality of experimental methodology still needs to be highly improved.
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4
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Xie W, Xu R, Fan C, Yang C, Chen H, Cao Y. 900 MHz Radiofrequency Field Induces Mitochondrial Unfolded Protein Response in Mouse Bone Marrow Stem Cells. Front Public Health 2021; 9:724239. [PMID: 34513791 PMCID: PMC8428517 DOI: 10.3389/fpubh.2021.724239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 08/04/2021] [Indexed: 01/29/2023] Open
Abstract
Objective: To examine whether exposure of mouse bone marrow stromal cells (BMSC) to 900 MHz radiofrequency fields used in mobile communication devices can induce mitochondrial unfolded protein response (UPRmt). Methods: BMSCs were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 120 μW/cm2 power intensity for 4 h/d for 5 consecutive days. Cells in sham group (SH) were cultured in RF exposure system, but without RF radiation. The positive control cells were irradiated with 6 Gy X-ray at a dose rate of 1.103 Gy/min (XR). To inhibit the upstream molecular JNK2 of UPRmt, cells in siRNA + RF, and siRNA + XR group were also pretreated with 100 nM siRNA-JNK2 for 48 h before RF/XR exposure. Thirty minutes, 4 h, and 24 h post-RF/XR exposure, cells were collected, the level of ROS was measured with flow cytometry, the expression levels of UPRmt-related proteins were detected using western blot analysis. Results: Compared with Sham group, the level of ROS in RF and XR group was significantly increased 30 min and 4 h post-RF/XR exposure (P < 0.05), however, the RF/XR-induced increase of ROS level reversed 24 h post-RF/XR exposure. Compared with Sham group, the expression levels of HSP10/HSP60/ClpP proteins in cells of RF and XR group increased significantly 30 min and 4 h post-RF/XR exposure (P < 0.05), however, the RF/XR-induced increase of HSP10/HSP60/ClpP protein levels reversed 24 h post-RF exposure. After interfering with siRNA-JNK2, the RF/XR exposures could not induce the increase of HSP10/HSP60/ClpP protein levels any more. Conclusions: The exposure of 900 MHz RF at 120 μW/cm2 power flux density could increase ROS level and activate a transient UPRmt in BMSC cells. Mitochondrial homeostasis in term of protein folding ability is restored 24 h post-RF exposure. Exposure to RF in our experimental condition did not cause permanent and severe mitochondrial dysfunctions. However, the detailed underlying molecular mechanism of RF-induced UPRmt remains to be further studied.
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Affiliation(s)
- Wen Xie
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
| | - Rui Xu
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
| | - Caiyun Fan
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
| | - Chunyu Yang
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
| | - Haiyan Chen
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
| | - Yi Cao
- Department of Toxicology, School of Public Health, Medical College of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou, China
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Foster KR, Miyakoshi J, Verschaeve L. Comments on the "Evaluation of the Genotoxicity of Cell Phone Radiofrequency Radiation in Male and Female Rats and Mice Following Subchronic Exposure" by Smith-Roe et al. Environ Mol Mutagen 2020; 61:291-293. [PMID: 31883146 DOI: 10.1002/em.22353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 12/22/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Kenneth R Foster
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Junji Miyakoshi
- Research Institute for Sustainable Humanosphere, Kyoto University, Kyoto, Japan
| | - Luc Verschaeve
- Service Risk and Health Impact Assessment, Sciensano, Brussels, Belgium
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Abstract
Birds can use two kinds of information from the geomagnetic field for navigation: the direction of the field lines as a compass and probably magnetic intensity as a component of the navigational ‘map’. The direction of the magnetic field appears to be sensed via radical pair processes in the eyes, with the crucial radical pairs formed by cryptochrome. It is transmitted by the optic nerve to the brain, where parts of the visual system seem to process the respective information. Magnetic intensity appears to be perceived by magnetite-based receptors in the beak region; the information is transmitted by the ophthalmic branch of the trigeminal nerve to the trigeminal ganglion and the trigeminal brainstem nuclei. Yet in spite of considerable progress in recent years, many details are still unclear, among them details of the radical pair processes and their transformation into a nervous signal, the precise location of the magnetite-based receptors and the centres in the brain where magnetic information is combined with other navigational information for the navigational processes.
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Affiliation(s)
- Roswitha Wiltschko
- FB Biowissenschaften, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| | - Wolfgang Wiltschko
- FB Biowissenschaften, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
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7
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Miller AB, Sears ME, Morgan LL, Davis DL, Hardell L, Oremus M, Soskolne CL. Risks to Health and Well-Being From Radio-Frequency Radiation Emitted by Cell Phones and Other Wireless Devices. Front Public Health 2019; 7:223. [PMID: 31457001 PMCID: PMC6701402 DOI: 10.3389/fpubh.2019.00223] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/25/2019] [Indexed: 12/14/2022] Open
Abstract
Radiation exposure has long been a concern for the public, policy makers, and health researchers. Beginning with radar during World War II, human exposure to radio-frequency radiation (RFR) technologies has grown substantially over time. In 2011, the International Agency for Research on Cancer (IARC) reviewed the published literature and categorized RFR as a "possible" (Group 2B) human carcinogen. A broad range of adverse human health effects associated with RFR have been reported since the IARC review. In addition, three large-scale carcinogenicity studies in rodents exposed to levels of RFR that mimic lifetime human exposures have shown significantly increased rates of Schwannomas and malignant gliomas, as well as chromosomal DNA damage. Of particular concern are the effects of RFR exposure on the developing brain in children. Compared with an adult male, a cell phone held against the head of a child exposes deeper brain structures to greater radiation doses per unit volume, and the young, thin skull's bone marrow absorbs a roughly 10-fold higher local dose. Experimental and observational studies also suggest that men who keep cell phones in their trouser pockets have significantly lower sperm counts and significantly impaired sperm motility and morphology, including mitochondrial DNA damage. Based on the accumulated evidence, we recommend that IARC re-evaluate its 2011 classification of the human carcinogenicity of RFR, and that WHO complete a systematic review of multiple other health effects such as sperm damage. In the interim, current knowledge provides justification for governments, public health authorities, and physicians/allied health professionals to warn the population that having a cell phone next to the body is harmful, and to support measures to reduce all exposures to RFR.
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Affiliation(s)
- Anthony B. Miller
- Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
| | - Margaret E. Sears
- Ottawa Hospital Research Institute, Prevent Cancer Now, Ottawa, ON, Canada
| | - L. Lloyd Morgan
- Environmental Health Trust, Teton Village, WY, United States
| | - Devra L. Davis
- Environmental Health Trust, Teton Village, WY, United States
| | - Lennart Hardell
- The Environment and Cancer Research Foundation, Örebro, Sweden
| | - Mark Oremus
- School of Public Health and Health Systems, University of Waterloo, Waterloo, ON, Canada
| | - Colin L. Soskolne
- School of Public Health, University of Alberta, Edmonton, AB, Canada
- Health Research Institute, University of Canberra, Canberra, ACT, Australia
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8
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Parmar K, Tandon R, Kumar N, Garg RK. Variations in electroencephalography with mobile phone usage in medical students. Neurol India 2019; 67:235-241. [PMID: 30860126 DOI: 10.4103/0028-3886.253610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background Electromagnetic fields (EMFs) emitted by cellular telephones may cause neurological ill effects like cognitive dysfunction, emotional instability, and even brain tumors. Slowing of brain activity on electroencephalography (EEG) has been shown. However, these findings need further validation. Aims EEG changes and adverse effects experienced following cell-phone use were studied. Settings and Design The study was conducted in the Department of Neurology of a tertiary care university hospital in India on North Indian students of the University, from August 2017 to October 2017. Materials and Methods Twenty-one students underwent video-EEG recording before and after application of Samsung GT-56312 dual SIM smart phone in switched off, switched on, and switched on mode with conversation. Statistical Analysis Used Average EEG frequencies and amplitudes were calculated for different brain regions. Chi-square tests and t-tests were used for comparison between variables. Results The mean age of 7 (33.3%) male and 14 (66.7%) female subjects was 20.76 ± 1.48 years. The average EEG frequencies following mobile phone application with conversation were higher and the amplitudes lower than the baseline values. Frequencies were greater on the right side. Slow waves were detected in the frontal region in 38.1%, in the parietal region in 33.3%, in the occipital and temporal region in 19.1%; and, generalized slow waves were seen in 9.5% students. During the experiment, 23.8% experienced headache, 19% experienced irritation, and 9.5% felt drowsy. Headache and loss of concentration (33.3%), sleep disturbances (28.6%), and fatigue (19%) were frequent in daily life. Conclusions Experimental application of mobile phones may lead to some EEG changes and certain ill effects on the well-being. Hence, prolonged use of these gadgets warrants caution.
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Affiliation(s)
- Kanak Parmar
- Department of Medicine, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Ruchika Tandon
- Department of Medicine, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Neeraj Kumar
- Department of Neurology, King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Ravindra Kumar Garg
- Department of Neurology, King George's Medical University, Lucknow, Uttar Pradesh, India
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9
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Zong L, Gao Z, Xie W, Tong J, Cao Y. Role of NF-κB activation in mouse bone marrow stromal cells exposed to 900-MHz radiofrequency fields (RF). J Toxicol Environ Health A 2019; 82:46-51. [PMID: 30704354 DOI: 10.1080/15287394.2018.1553372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a primary transcription factor which plays a key role in several cellular processes including proliferation and survival. It is well known that exposure to non-ionizing radiofrequency fields (RFs), which are ubiquitous, resulted in interaction with cellular components. The aim of the study was thus to examine whether exposure of mouse bone marrow stromal cells (BMSC) to RF also resulted in cellular interactions. BMSC were exposed to 900 MHz RF at 120 μW/cm2 power intensity for 4 hr/day for 5 consecutive days. The relative protein expression levels of NF-κB in the cytoplasm and nucleus of RF-exposed cells were compared to non-RF-exposed controls. At 30-min post-RF exposure, a significant decrease in protein expression of NF-κB in the cytoplasm was accompanied by a concomitant increase in nuclear NF-κB protein expression levels. Similar responses were noted in the cytoplasm and nuclear NF-κB levels at 2 hr with a return to control concentrations in primary transcription factor at 24-hr post-RF treatment. Daily incubation of BAY 11-7082, an inhibitor of NF-κB, for 90 min for 5 days followed by RF each day prevented the fall in cytoplasmic NF-κB and rise in nuclear primary transcription factor at 30 min and 2 hr. There were no marked alterations at 24 hr. Data showed that the effects of RF treatment on BMSC involved transient activation of NF-κB which may be attributed to RF-mediated cellular perturbation as evidenced by consequences of BAY 11-7082 inhibition.
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Affiliation(s)
- Lin Zong
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Zhen Gao
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Wen Xie
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Jian Tong
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Yi Cao
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
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10
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Zong L, Gao Z, Xie W, Tong J, Cao Y. Role of NF-κB activation in mouse bone marrow stromal cells exposed to 900 MHz radiofrequency fields (RF). J Toxicol Environ Health A 2019; 82:157-162. [PMID: 30663538 DOI: 10.1080/15287394.2018.1564196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a primary transcription factor which plays a key role in several cellular processes including proliferation and survival. It is well-known that exposure to non-ionizing radiofrequency fields (RF), which are ubiquitous, interact with cellular components. The aim of the study was thus to examine whether exposure of mouse bone marrow stromal cells (BMSC) to RF also resulted in cellular interactions. BMSC were exposed to 900 MHz RF at 120 μW/cm2 power intensity for 4 hr/day for 5 consecutive days. The relative protein expression levels of NF-κB in the cytoplasm and nucleus of RF-exposed cells were compared to non-RF-exposed controls. At 30 min post-RF exposure a significant decrease in protein expression of NF-κB in the cytoplasm was accompanied by a concomitant increase in nuclear NF-κB protein expression levels. Similar responses were noted in the cytoplasm and nuclear NF-κB levels at 2 hr with a return to control concentrations in primary transcription factor at 24 hr post-RF treatment. Daily incubation of BAY 11-7082 an inhibitor of NF-κB for 90 min for 5 days followed by RF each day prevented the fall in cytoplasmic NF-κB and rise in nuclear primary transcription factor at 30 min and 2 hr. There were no marked alterations at 24 hr. Data showed that the effects of RF treatment on BMSC involved transient activation of NF-κB which may be attributed to RF-mediated cellular perturbation as evidenced by consequences of BAY 11-7082 inhibition.
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Affiliation(s)
- Lin Zong
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Zhen Gao
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Wen Xie
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Jian Tong
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
| | - Yi Cao
- a School of Public Health , Medical College of Soochow University , Suzhou , Jiangsu Province , People's Republic of China
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11
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Lee JS, Kim JY, Kim HJ, Kim JC, Lee JS, Kim N, Park MJ. Effects of combined radiofrequency field exposure on amyloid-beta-induced cytotoxicity in HT22 mouse hippocampal neurones. J Radiat Res 2016; 57:620-626. [PMID: 27325640 PMCID: PMC5137286 DOI: 10.1093/jrr/rrw040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 02/02/2016] [Accepted: 03/04/2016] [Indexed: 06/06/2023]
Abstract
Alzheimer's disease (AD) is the most common progressive and irreversible neurodegenerative disease and it is caused by neuronal death in the brain. Recent studies have shown that non-ionizing radiofrequency (RF) radiation has some beneficial cognitive effects in animal models of AD. In this study, we examined the effect of combined RF radiation on amyloid-beta (Aβ)-induced cytotoxicity in HT22 rat hippocampal neurons. Treatment with Aβ suppressed HT22 cell proliferation in a concentration-dependent manner. RF exposure did not affect cell proliferation, and also had a marginal effect on Aβ-induced suppression of growth in HT22 cells. Cell cycle analysis showed that Aβ decreased the G1 fraction and increased the subG1 fraction, indicating increased apoptosis. Accordingly, Aβ increased the annexin V/propidium iodide (PI)-positive cell fraction and the degradation of poly (ADP ribose) polymerase and caspase-3 in HT22 cells. However, RF alone and the combination of Aβ and RF did not affect these events significantly. Aβ increased reactive oxygen species (ROS) generation, thereby suppressing cell proliferation. This was abrogated by N-acetylcysteine (NAC) treatment, indicating that Aβ-induced ROS generation is the main cause of suppression of proliferation. NAC also restored Aβ-induced annexin V/PI-positive cell populations. However, RF did not have a significant impact on these events. Finally, Aβ stimulated the ataxia telangiectasia and Rad3-related protein/checkpoint kinase 1 DNA single-strand breakage pathway, and enhanced beta-site amyloid precursor protein expression; RF had no effect on them. Taken together, our results demonstrate that RF exposure did not significantly affect the Aβ-induced decrease of cell proliferation, increase of ROS production, or induction of cell death in these cells.
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Affiliation(s)
- Jong-Sun Lee
- Division of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Nowongil 75, Nowon-Gu, Seoul 139-706, Korea
| | - Jeong-Yub Kim
- Division of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Nowongil 75, Nowon-Gu, Seoul 139-706, Korea
- Department of Pathology, College of Medicine, Korea University, Seoul 136-705, Korea
| | - Hee-Jin Kim
- Division of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Nowongil 75, Nowon-Gu, Seoul 139-706, Korea
| | - Jeong Cheol Kim
- Division of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Nowongil 75, Nowon-Gu, Seoul 139-706, Korea
| | - Jae-Seon Lee
- Division of Biomedical Sciences, College of Medicine, Inha University, Incheon 400-712, Korea
| | - Nam Kim
- School of Information and Communication Engineering, Chungbuk National University, Cheongju 362-763, Korea
| | - Myung-Jin Park
- Division of Radiation Cancer Research, Research Center for Radio-Senescence, Korea Institute of Radiological and Medical Sciences, Nowongil 75, Nowon-Gu, Seoul 139-706, Korea
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12
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Wood AW, Lajevardipour A, McIntosh RL. Lessons and Perspectives from a 25-Year Bioelectromagnetics Research Program. Int J Environ Res Public Health 2016; 13:ijerph13100950. [PMID: 27669282 PMCID: PMC5086689 DOI: 10.3390/ijerph13100950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 11/29/2022]
Abstract
The question of whether electromagnetic fields from electric power or telecommunications systems can be linked unequivocally to health detriments has occupied scientific research endeavors for nearly half a century. For 25 years, the bioelectromagnetic research group at Swinburne University in Melbourne, Australia, has pursued a series of investigations with relevant endpoints, such as neurophysiological and neuropsychological effects, cell calcium level changes, proliferation, and genotoxic effects. Most have shown no significant changes due to fields, however, in some pilot studies significant changes were revealed, but in most cases these were not replicated in follow-up studies. This highlights a feature of this research area, generally; the unambiguous identification of small changes in noisy data where the understanding of possible interaction mechanisms is lacking. On the other hand, mathematical modelling studies, particularly with respect to fields near metallic implants, in workers exposed to fields in harsh environmental conditions and at very high frequencies (THz), continue to add to the expanding knowledge database on the characteristics of the complex electromagnetic environment we live in today.
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Affiliation(s)
- Andrew W Wood
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
| | - Alireza Lajevardipour
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
| | - Robert L McIntosh
- School of Health Sciences, Swinburne University of Technology, Melbourne, VIC 3122, Australia.
- Chief Technology Office, Telstra Corporation, Melbourne, VIC 3122, Australia.
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13
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Dokumaci AS, Pouymayou B, Kreis R, Boesch C. Motion-insensitive determination of B1+ amplitudes based on the bloch-siegert shift in single voxels of moving organs including the human heart. Magn Reson Med 2015; 75:1867-74. [PMID: 26185908 DOI: 10.1002/mrm.25763] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 04/10/2015] [Accepted: 04/15/2015] [Indexed: 11/08/2022]
Abstract
PURPOSE To reliably determine the amplitude of the transmit radiofrequency ( B1+) field in moving organs like the liver and heart, where most current techniques are usually not feasible. METHODS B1+ field measurement based on the Bloch-Siegert shift induced by a pair of Fermi pulses in a double-triggered modified Point RESolved Spectroscopy (PRESS) sequence with motion-compensated crusher gradients has been developed. Performance of the sequence was tested in moving phantoms and in muscle, liver, and heart of six healthy volunteers each, using different arrangements of transmit/receive coils. RESULTS B1+ determination in a moving phantom was almost independent of type and amplitude of the motion and agreed well with theory. In vivo, repeated measurements led to very small coefficients of variance (CV) if the amplitude of the Fermi pulse was chosen above an appropriate level (CV in muscle 0.6%, liver 1.6%, heart 2.3% with moderate amplitude of the Fermi pulses and 1.2% with stronger Fermi pulses). CONCLUSION The proposed sequence shows a very robust determination of B1+ in a single voxel even under challenging conditions (transmission with a surface coil or measurements in the heart without breath-hold).
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Affiliation(s)
- Ayse Sila Dokumaci
- Department of Clinical Research and Department of Radiology, University of Bern, Switzerland
| | - Bertrand Pouymayou
- Department of Clinical Research and Department of Radiology, University of Bern, Switzerland
| | - Roland Kreis
- Department of Clinical Research and Department of Radiology, University of Bern, Switzerland
| | - Chris Boesch
- Department of Clinical Research and Department of Radiology, University of Bern, Switzerland
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14
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Hardell L, Carlberg M. Increasing rates of brain tumours in the Swedish national inpatient register and the causes of death register. Int J Environ Res Public Health 2015; 12:3793-813. [PMID: 25854296 PMCID: PMC4410216 DOI: 10.3390/ijerph120403793] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/25/2015] [Accepted: 03/30/2015] [Indexed: 12/23/2022]
Abstract
Radiofrequency emissions in the frequency range 30 kHz-300 GHz were evaluated to be Group 2B, i.e., "possibly", carcinogenic to humans by the International Agency for Research on Cancer (IARC) at WHO in May 2011. The Swedish Cancer Register has not shown increasing incidence of brain tumours in recent years and has been used to dismiss epidemiological evidence on a risk. In this study we used the Swedish National Inpatient Register (IPR) and Causes of Death Register (CDR) to further study the incidence comparing with the Cancer Register data for the time period 1998-2013 using joinpoint regression analysis. In the IPR we found a joinpoint in 2007 with Annual Percentage Change (APC) +4.25%, 95% CI +1.98, +6.57% during 2007-2013 for tumours of unknown type in the brain or CNS. In the CDR joinpoint regression found one joinpoint in 2008 with APC during 2008-2013 +22.60%, 95% CI +9.68, +37.03%. These tumour diagnoses would be based on clinical examination, mainly CT and/or MRI, but without histopathology or cytology. No statistically significant increasing incidence was found in the Swedish Cancer Register during these years. We postulate that a large part of brain tumours of unknown type are never reported to the Cancer Register. Furthermore, the frequency of diagnosis based on autopsy has declined substantially due to a general decline of autopsies in Sweden adding further to missing cases. We conclude that the Swedish Cancer Register is not reliable to be used to dismiss results in epidemiological studies on the use of wireless phones and brain tumour risk.
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Affiliation(s)
- Lennart Hardell
- Department of Oncology, Faculty of Medicine and Health, Örebro University, SE-701 82 Örebro, Sweden.
| | - Michael Carlberg
- Department of Oncology, Faculty of Medicine and Health, Örebro University, SE-701 82 Örebro, Sweden.
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15
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Eltiti S, Wallace D, Russo R, Fox E. Aggregated data from two double-blind base station provocation studies comparing individuals with idiopathic environmental intolerance with attribution to electromagnetic fields and controls. Bioelectromagnetics 2015; 36:96-107. [PMID: 25644455 DOI: 10.1002/bem.21892] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 11/19/2014] [Indexed: 11/08/2022]
Abstract
Data from two previous studies were aggregated to provide a statistically powerful test of whether exposure to electromagnetic fields (EMFs) produced by telecommunication base stations negatively affects well-being in individuals who report idiopathic environmental illness with attribution to electromagnetic fields (IEI-EMF) and control participants. A total of 102 IEI-EMF and 237 controls participated in open provocation trials and 88 IEI-EMF and 231 controls went on to complete double-blind trials in which they were exposed to EMFs from a base station emitting either a Global System for Mobile Communication and Universal Mobile Telecommunications System or a Terrestrial Trunked Radio Telecommunications System signal. Both experiments included a comparison sham condition. Visual analog and symptom scales measured subjective well-being. Results showed that IEI-EMF participants reported lower levels of well-being during real compared to sham exposure during open provocation, but not during double-blind trials. Additionally, participants reported lower levels of well-being during high compared to low load trials and this did not interact with radiofrequency-EMF exposure. These findings are consistent with a growing body of literature indicating there is no causal relationship between short-term exposure to EMFs and subjective well-being in members of the public whether or not they report perceived sensitivity to EMFs.
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Affiliation(s)
- Stacy Eltiti
- Department of Psychology and Centre for Brain Science, University of Essex, Wivenhoe Park, Essex, UK; Rosemead School of Psychology, Biola University, La Mirada, California
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Rosado MM, Nasta F, Prisco MG, Lovisolo GA, Marino C, Pioli C. Effects of GSM-modulated 900 MHz radiofrequency electromagnetic fields on the hematopoietic potential of mouse bone marrow cells. Bioelectromagnetics 2014; 35:559-67. [PMID: 25256206 DOI: 10.1002/bem.21880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 07/29/2014] [Indexed: 11/09/2022]
Abstract
Studies describing the influence of radiofrequency electromagnetic fields on bone marrow cells (BMC) often lack functional data. We examined the effects of in vivo exposure to a Global System for Mobile Communications (GSM) modulated 900 MHz RF fields on BMC using two transplantation models. X-irradiated syngeneic mice were injected with BMC from either RF-field-exposed, sham-exposed or cage control mice. Twelve weeks after transplantation, no differences in thymocyte number, frequency of subpopulations and cell proliferation were found in mice receiving BMC from either group. Also, in the spleen cell number, percentages of B/T cells, B/T-cell proliferation, and interferon γ (IFN-γ) production were similar in all groups. In parallel, a mixture of BMC from congenic sham- and RF-exposed mice were co-transplanted into lymphopenic Rag2 deficient mice. BMC from RF-exposed and sham-exposed mice displayed no advantage or disadvantage when competing for the replenishment of lymphatic organs with mature lymphocytes in Rag2 deficient mice. This model revealed that BMC from sham-exposed and RF-exposed mice were less efficient than BMC from cage control mice in repopulating the thymus, an effect likely due to restraint stress. In conclusion, our results showed no effects of in vivo exposure to GSM-modulated RF-fields on the ability of bone marrow (BM) precursors to long-term reconstitute peripheral T and B cell compartments.
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17
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Vijayalaxmi, Scarfi MR. International and national expert group evaluations: biological/health effects of radiofrequency fields. Int J Environ Res Public Health 2014; 11:9376-408. [PMID: 25211777 PMCID: PMC4199025 DOI: 10.3390/ijerph110909376] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/27/2014] [Accepted: 08/27/2014] [Indexed: 12/21/2022]
Abstract
The escalated use of various wireless communication devices, which emit non-ionizing radiofrequency (RF) fields, have raised concerns among the general public regarding the potential adverse effects on human health. During the last six decades, researchers have used different parameters to investigate the effects of in vitro and in vivo exposures of animals and humans or their cells to RF fields. Data reported in peer-reviewed scientific publications were contradictory: some indicated effects while others did not. International organizations have considered all of these data as well as the observations reported in human epidemiological investigations to set-up the guidelines or standards (based on the quality of published studies and the "weight of scientific evidence" approach) for RF exposures in occupationally exposed individuals and the general public. Scientists with relevant expertise in various countries have also considered the published data to provide the required scientific information for policy-makers to develop and disseminate authoritative health information to the general public regarding RF exposures. This paper is a compilation of the conclusions, on the biological effects of RF exposures, from various national and international expert groups, based on their analyses. In general, the expert groups suggested a reduction in exposure levels, precautionary approach, and further research.
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Affiliation(s)
- Vijayalaxmi
- Department of Radiology, University of Texas Health Science Center, San Antonio, TX 78299, USA.
| | - Maria R Scarfi
- CNR-Institute for Electromagnetic Sensing of Environment, Napoli 80124, Italy.
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18
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Kavokin K, Chernetsov N, Pakhomov A, Bojarinova J, Kobylkov D, Namozov B. Magnetic orientation of garden warblers (Sylvia borin) under 1.4 MHz radiofrequency magnetic field. J R Soc Interface 2014; 11:20140451. [PMID: 24942848 PMCID: PMC4208380 DOI: 10.1098/rsif.2014.0451] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 05/28/2014] [Indexed: 11/12/2022] Open
Abstract
We report on the experiments on orientation of a migratory songbird, the garden warbler (Sylvia borin), during the autumn migration period on the Courish Spit, Eastern Baltics. Birds in experimental cages, deprived of visual information, showed the seasonally appropriate direction of intended flight with respect to the magnetic meridian. Weak radiofrequency (RF) magnetic field (190 nT at 1.4 MHz) disrupted this orientation ability. These results may be considered as an independent replication of earlier experiments, performed by the group of R. and W. Wiltschko with European robins (Erithacus rubecula). Confirmed outstanding sensitivity of the birds' magnetic compass to RF fields in the lower megahertz range demands for a revision of one of the mainstream theories of magnetoreception, the radical-pair model of birds' magnetic compass.
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Affiliation(s)
- Kirill Kavokin
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia A.F. Ioffe Physical Technical Institute, 26 Polytechnicheskaya, St Petersburg 194021, Russia
| | - Nikita Chernetsov
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia Biological Station Rybachy, Zoological Institute, 238535 Rybachy, Kaliningrad Region, Russia
| | - Alexander Pakhomov
- Biological Station Rybachy, Zoological Institute, 238535 Rybachy, Kaliningrad Region, Russia Moscow State University, Moscow 119991, Russia
| | - Julia Bojarinova
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
| | - Dmitry Kobylkov
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia Biological Station Rybachy, Zoological Institute, 238535 Rybachy, Kaliningrad Region, Russia
| | - Barot Namozov
- A.F. Ioffe Physical Technical Institute, 26 Polytechnicheskaya, St Petersburg 194021, Russia
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Cao Y, Tong J. Adaptive response in animals exposed to non-ionizing radiofrequency fields: some underlying mechanisms. Int J Environ Res Public Health 2014; 11:4441-8. [PMID: 24758897 PMCID: PMC4025035 DOI: 10.3390/ijerph110404441] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 03/30/2014] [Accepted: 04/03/2014] [Indexed: 12/21/2022]
Abstract
During the last few years, our research group has been investigating the phenomenon of adaptive response in animals exposed to non-ionizing radiofrequency fields. The results from several separate studies indicated a significant increase in survival, decreases in genetic damage as well as oxidative damage and, alterations in several cellular processes in mice pre-exposed to radiofrequency fields and subsequently subjected to sub-lethal or lethal doses of γ-radiation or injected with bleomycin, a radiomimetic chemical mutagen. These observations indicated the induction of adaptive response providing the animals the ability to resist subsequent damage. Similar studies conducted by independent researchers in mice and rats have supported our observation on increased survival. In this paper, we have presented a brief review of all of our own and other independent investigations on radiofrequency fields-induced adaptive response and some underlying mechanisms discussed.
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Affiliation(s)
- Yi Cao
- School of Public Health, Medical College of Soochow University, Suzhou 215123, China.
| | - Jian Tong
- School of Public Health, Medical College of Soochow University, Suzhou 215123, China.
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20
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Lagorio S, Röösli M. Mobile phone use and risk of intracranial tumors: a consistency analysis. Bioelectromagnetics 2013; 35:79-90. [PMID: 24375548 DOI: 10.1002/bem.21829] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 10/09/2013] [Indexed: 11/10/2022]
Abstract
A meta-analysis of studies on intracranial tumors and mobile phone use published by the end of 2012 was performed to evaluate the overall consistency of findings, assess the sensitivity of results to changes in the dataset, and try to detect the sources of between-study heterogeneity. Twenty-nine papers met our inclusion criteria. These papers reported on 47 eligible studies (17 on glioma, 15 on meningioma, 15 on acoustic neuroma), consisting of either primary investigations or pooled analyses. Five combinations of non-overlapping studies per outcome were identified. The combined relative risks (cRRs) in long-term mobile phone users (≥10 years) ranged between 0.98 (0.75-1.28) and 1.11 (0.86-1.44) for meningioma, with little heterogeneity across studies. High heterogeneity was detected across estimates of glioma and acoustic neuroma risk in long term users, with cRRs ranging between 1.19 (95% CI 0.86-1.64) and 1.40 (0.96-2.04), and from 1.14 (0.65-1.99) to 1.33 (0.65-2.73), respectively. A meta-regression of primary studies showed that the methodological differences embedded in the variable "study-group" explained most of the overall heterogeneity in results. Summary risk estimates based on heterogeneous findings should not be over-interpreted. Overall, the results of our study detract from the hypothesis that mobile phone use affects the occurrence of intracranial tumors. However, reproducibility (or lack of) is just one clue in the critical appraisal of epidemiological evidence. Based on other considerations, such as the limited knowledge currently available on risk beyond 15 years from first exposure, or following mobile phone use started in childhood, the pursuance of epidemiological surveillance is warranted.
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21
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Winklhofer M, Dylda E, Thalau P, Wiltschko W, Wiltschko R. Avian magnetic compass can be tuned to anomalously low magnetic intensities. Proc Biol Sci 2013; 280:20130853. [PMID: 23720547 DOI: 10.1098/rspb.2013.0853] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The avian magnetic compass works in a fairly narrow functional window around the intensity of the local geomagnetic field, but adjusts to intensities outside this range when birds experience these new intensities for a certain time. In the past, the geomagnetic field has often been much weaker than at present. To find out whether birds can obtain directional information from a weak magnetic field, we studied spontaneous orientation preferences of migratory robins in a 4 µT field (i.e. a field of less than 10 per cent of the local intensity of 47 µT). Birds can adjust to this low intensity: they turned out to be disoriented under 4 µT after a pre-exposure time of 8 h to 4 µT, but were able to orient in this field after a total exposure time of 17 h. This demonstrates a considerable plasticity of the avian magnetic compass. Orientation in the 4 µT field was not affected by local anaesthesia of the upper beak, but was disrupted by a radiofrequency magnetic field of 1.315 MHz, 480 nT, suggesting that a radical-pair mechanism still provides the directional information in the low magnetic field. This is in agreement with the idea that the avian magnetic compass may have developed already in the Mesozoic in the common ancestor of modern birds.
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Affiliation(s)
- Michael Winklhofer
- Department für Geo- und Umweltwissenschaften, Ludwig-Maximillians-Universität München, Theresienstrasse 41/IV, D-80333 Munich, Germany
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Vanderstraeten J, Verschaeve L. Gene and protein expression following exposure to radiofrequency fields from mobile phones. Environ Health Perspect 2008; 116:1131-1135. [PMID: 18795152 PMCID: PMC2535611 DOI: 10.1289/ehp.11279] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 05/09/2008] [Indexed: 05/26/2023]
Abstract
BACKGROUND Since 1999, several articles have been published on genome-wide and/or proteome-wide response after exposure to radiofrequency (RF) fields whose signal and intensities were similar to or typical of those of currently used mobile telephones. These studies were performed using powerful high-throughput screening techniques (HTSTs) of transcriptomics and/or proteomics, which allow for the simultaneous screening of the expression of thousands of genes or proteins. OBJECTIVES We reviewed these HTST-based studies and compared the results with currently accepted concepts about the effects of RF fields on gene expression. In this article we also discuss these last in light of the recent concept of microwave-assisted chemistry. DISCUSSION To date, the results of HTST-based studies of transcriptomics and/or proteomics after exposure to RF fields relevant to human exposure are still inconclusive, as most of the positive reports are flawed by methodologic imperfections or shortcomings. In addition, when positive findings were reported, no precise response pattern could be identified in a reproducible way. In particular, results from HTST studies tend to exclude the role of a cell stressor for exposure to RF fields at nonthermal intensities. However, on the basis of lessons from microwave-assisted chemistry, we can assume that RF fields might affect heat-sensitive gene or protein expression to an extent larger than would be predicted from temperature change only. But in all likelihood, this would concern intensities higher than those relevant to usual human exposure. CONCLUSIONS The precise role of transcriptomics and proteomics in the screening of bioeffects from exposure to RF fields from mobile phones is still uncertain in view of the lack of positively identified phenotypic change and the lack of theoretical, as well as experimental, arguments for specific gene and/or protein response patterns after this kind of exposure.
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Affiliation(s)
- Jacques Vanderstraeten
- Research Unit on Work Health and Environmental Toxicology, School of Public Health, Université Libre de Bruxelles, Brussels, Belgium.
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