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Halgamuge MN. Supervised Machine Learning Algorithms for Bioelectromagnetics: Prediction Models and Feature Selection Techniques Using Data from Weak Radiofrequency Radiation Effect on Human and Animals Cells. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E4595. [PMID: 32604814 PMCID: PMC7345599 DOI: 10.3390/ijerph17124595] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/10/2020] [Accepted: 06/18/2020] [Indexed: 11/20/2022]
Abstract
The emergence of new technologies to incorporate and analyze data with high-performance computing has expanded our capability to accurately predict any incident. Supervised Machine learning (ML) can be utilized for a fast and consistent prediction, and to obtain the underlying pattern of the data better. We develop a prediction strategy, for the first time, using supervised ML to observe the possible impact of weak radiofrequency electromagnetic field (RF-EMF) on human and animal cells without performing in-vitro laboratory experiments. We extracted laboratory experimental data from 300 peer-reviewed scientific publications (1990-2015) describing 1127 experimental case studies of human and animal cells response to RF-EMF. We used domain knowledge, Principal Component Analysis (PCA), and the Chi-squared feature selection techniques to select six optimal features for computation and cost-efficiency. We then develop grouping or clustering strategies to allocate these selected features into five different laboratory experiment scenarios. The dataset has been tested with ten different classifiers, and the outputs are estimated using the k-fold cross-validation method. The assessment of a classifier's prediction performance is critical for assessing its suitability. Hence, a detailed comparison of the percentage of the model accuracy (PCC), Root Mean Squared Error (RMSE), precision, sensitivity (recall), 1 - specificity, Area under the ROC Curve (AUC), and precision-recall (PRC Area) for each classification method were observed. Our findings suggest that the Random Forest algorithm exceeds in all groups in terms of all performance measures and shows AUC = 0.903 where k-fold = 60. A robust correlation was observed in the specific absorption rate (SAR) with frequency and cumulative effect or exposure time with SAR×time (impact of accumulated SAR within the exposure time) of RF-EMF. In contrast, the relationship between frequency and exposure time was not significant. In future, with more experimental data, the sample size can be increased, leading to more accurate work.
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Affiliation(s)
- Malka N Halgamuge
- Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
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Shen X, Li T, Xie X, Feng Y, Chen Z, Yang H, Wu C, Deng S, Liu Y. PLGA-Based Drug Delivery Systems for Remotely Triggered Cancer Therapeutic and Diagnostic Applications. Front Bioeng Biotechnol 2020; 8:381. [PMID: 32432092 PMCID: PMC7214837 DOI: 10.3389/fbioe.2020.00381] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 04/06/2020] [Indexed: 12/16/2022] Open
Abstract
Intelligent drug delivery systems based on nanotechnology have been widely developed and investigated in the field of nanomedicine since they were able to maximize the therapeutic efficacy and minimize the undesirable adverse effects. Among a variety of organic or inorganic nanomaterials available to fabricate drug delivery systems (DDSs) for cancer therapy and diagnosis, poly(D,L-lactic-co-glycolic acid) (PLGA) has been extensively employed due to its biocompatibility and biodegradability. In this paper, we review the recent status of research on the application of PLGA-based drug delivery systems (DDSs) in remotely triggered cancer therapy and the strategies for tumor imaging provided by PLGA-based DDSs. We firstly discuss the employment of PLGA-based DDSs for remotely triggered cancer therapy, including photo-triggered, ultrasound-triggered, magnetic field-triggered, and radiofrequency-triggered cancer therapy. Photo-triggered cancer therapy involves photodynamic therapy (PDT), photothermal therapy (PTT), and photo-triggered chemotherapeutics release. Ultrasound-triggered cancer therapy involves high intensity focused ultrasound (HIFU) treatment, ultrasound-triggered chemotherapeutics release, and ultrasound-enhanced efficiency of gene transfection. The strategies which endows PLGA-based DDSs with imaging properties and the PLGA-based cancer theranostics are further discussed. Additionally, we also discuss the targeting strategies which provide PLGA-based DDSs with passive, active or magnetic tumor-targeting abilities. Numerous studies cited in our review demonstrate the great potential of PLGA-based DDSs as effective theranostic agent for cancer therapy and diagnosis.
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Affiliation(s)
- Xue Shen
- Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China
| | - Tingting Li
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China.,Center for Information in Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaoxue Xie
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Yi Feng
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Zhongyuan Chen
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Hong Yang
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China.,Center for Information in Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Chunhui Wu
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China.,Center for Information in Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Shengqi Deng
- Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China
| | - Yiyao Liu
- School of Life Sciences and Technology, University of Electronic Science and Technology of China, Chengdu, China.,Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
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Halgamuge MN, Skafidas E, Davis D. A meta-analysis of in vitro exposures to weak radiofrequency radiation exposure from mobile phones (1990-2015). ENVIRONMENTAL RESEARCH 2020; 184:109227. [PMID: 32199316 DOI: 10.1016/j.envres.2020.109227] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 01/29/2020] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
To function, mobile phone systems require transmitters that emit and receive radiofrequency signals over an extended geographical area exposing humans in all stages of development ranging from in-utero, early childhood, adolescents and adults. This study evaluates the question of the impact of radiofrequency radiation on living organisms in vitro studies. In this study, we abstract data from 300 peer-reviewed scientific publications (1990-2015) describing 1127 experimental observations in cell-based in vitro models. Our first analysis of these data found that out of 746 human cell experiments, 45.3% indicated cell changes, whereas 54.7% indicated no changes (p = 0.001). Realizing that there are profound distinctions between cell types in terms of age, rate of proliferation and apoptosis, and other characteristics and that RF signals can be characterized in terms of polarity, information content, frequency, Specific Absorption Rate (SAR) and power, we further refined our analysis to determine if there were some distinct properties of negative and positive findings associated with these specific characteristics. We further analyzed the data taking into account the cumulative effect (SAR × exposure time) to acquire the cumulative energy absorption of experiments due to radiofrequency exposure, which we believe, has not been fully considered previously. When the frequency of signals, length and type of exposure, and maturity, rate of growth (doubling time), apoptosis and other properties of individual cell types are considered, our results identify a number of potential non-thermal effects of radiofrequency fields that are restricted to a subset of specific faster-growing less differentiated cell types such as human spermatozoa (based on 19 reported experiments, p-value = 0.002) and human epithelial cells (based on 89 reported experiments, p-value < 0.0001). In contrast, for mature, differentiated adult cells of Glia (p = 0.001) and Glioblastoma (p < 0.0001) and adult human blood lymphocytes (p < 0.0001) there are no statistically significant differences for these more slowly reproducing cell lines. Thus, we show that RF induces significant changes in human cells (45.3%), and in faster-growing rat/mouse cell dataset (47.3%). In parallel with this finding, further analysis of faster-growing cells from other species (chicken, rabbit, pig, frog, snail) indicates that most undergo significant changes (74.4%) when exposed to RF. This study confirms observations from the REFLEX project, Belyaev and others that cellular response varies with signal properties. We concur that differentiation of cell type thus constitutes a critical piece of information and should be useful as a reference for many researchers planning additional studies. Sponsorship bias is also a factor that we did not take into account in this analysis.
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Affiliation(s)
- Malka N Halgamuge
- Department Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Efstratios Skafidas
- Department Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Devra Davis
- Environmental Health Trust, Teton Village, WY, 83025, USA
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Fang Y, Li HY, Yin HH, Xu SH, Ren WW, Ding SS, Tang WZ, Xiang LH, Wu R, Guan X, Zhang K. Radiofrequency-Sensitive Longitudinal Relaxation Tuning Strategy Enabling the Visualization of Radiofrequency Ablation Intensified by Magnetic Composite. ACS APPLIED MATERIALS & INTERFACES 2019; 11:11251-11261. [PMID: 30874421 DOI: 10.1021/acsami.9b02401] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
As a minimally invasive heat source, radiofrequency (RF) ablation still encounters potential damages to the surrounding normal tissues because of heat diffusion, high power, and long time. With a comprehensive understanding of the current state of the art on RF ablation, a magnetic composite using porous hollow iron oxide nanoparticles (HIONs) as carriers to load dl-menthol (DLM) has been engineered. This composite involves two protocols for enhancing RF ablation, that is, HION-mediated magnetothermal conversion in RF field and RF solidoid vaporation (RSV)-augmented inertial cavitation, respectively. A combined effect based on two protocols is found to improve energy transformation, and further, along with hydrophobic DLM-impeded heat diffusion, improve the energy utilization efficiency and significantly facilitate ex vivo and in vivo RF ablation. More significantly, in vitro and in vivo RSV processes and RSV-augmented inertial cavitation for RF ablation can be monitored by T1-weighted magnetic resonance imaging (MRI) via an RF-sensitive longitudinal relaxation tuning strategy because the RSV process can deplete DLM and make HION carriers permeable to water molecules, consequently improving the longitudinal relaxation rate of HIONs and enhancing T1-weighted MRI. Therefore, this RF-sensitive magnetic composite holds a great potential in lowering the power and time of RF ablation and improving its therapeutic safety.
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Affiliation(s)
- Yan Fang
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Hong-Yan Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Hao-Hao Yin
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Shi-Hao Xu
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Wei-Wei Ren
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Shi-Si Ding
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Wei-Zhong Tang
- A Guangxi Collaborative Innovation Center for Biomedicine, and Affiliated Tumor Hospital of Guangxi Medical University , Guangxi Medical University , 22 Shuang Yong Road , Nanning , Guangxi 530021 , P. R. China
| | - Li-Hua Xiang
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Rong Wu
- Department of Medical Ultrasound, Shanghai General Hospital , Shanghai Jiaotong University School of Medicine , 85 Wu-jin Road , Shanghai 200080 , P. R. China
| | - Xin Guan
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
| | - Kun Zhang
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine , Tongji University , 301 Yan-chang-zhong Road , Shanghai 200072 , P. R. China
- A Guangxi Collaborative Innovation Center for Biomedicine, and Affiliated Tumor Hospital of Guangxi Medical University , Guangxi Medical University , 22 Shuang Yong Road , Nanning , Guangxi 530021 , P. R. China
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Affiliation(s)
- G. Gandhi
- Department of Human Genetics, Guru Nanak Dev University , Amritsar 143 005, Punjab, India
| | - Anita Gandhi
- Department of Human Genetics, Guru Nanak Dev University , Amritsar 143 005, Punjab, India
| | - P. Singh
- Department of Human Genetics, Guru Nanak Dev University , Amritsar 143 005, Punjab, India
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Kharlanov AV. Forced acoustic oscillations of biological cell. Bioelectromagnetics 2017; 38:613-617. [PMID: 28836692 DOI: 10.1002/bem.22078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 08/02/2017] [Indexed: 01/24/2023]
Abstract
This article considers the possibility of excitation of acoustic oscillations in a cell by electromagnetic waves. In this process, not only the frequency but also the length of a wave is of great importance. It is also reported that the pulse signal can be more effective than harmonic signal, and the pulse length is not essential. In accordance with this fact, it is possible to explain the biological effects of electromagnetic waves and to develop new medical electronic devices. Bioelectromagnetics. 38:613-617, 2017. © 2017 Wiley Periodicals, Inc.
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Zhang K, Li P, He Y, Bo X, Li X, Li D, Chen H, Xu H. Synergistic retention strategy of RGD active targeting and radiofrequency-enhanced permeability for intensified RF & chemotherapy synergistic tumor treatment. Biomaterials 2016; 99:34-46. [PMID: 27209261 DOI: 10.1016/j.biomaterials.2016.05.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/06/2016] [Accepted: 05/09/2016] [Indexed: 12/22/2022]
Abstract
Despite gaining increasing attention, chelation of multiple active targeting ligands greatly increase the formation probability of protein corona, disabling active targeting. To overcome it, a synergistic retention strategy of RGD-mediated active targeting and radiofrequency (RF) electromagnetic field-enhanced permeability has been proposed here. It is validated that such a special synergistic retention strategy can promote more poly lactic-co-glycolic acid (PLGA)-based capsules encapsulating camptothecin (CPT) and solid DL-menthol (DLM) to enter and retain in tumor in vitro and in vivo upon exposure to RF irradiation, receiving an above 8 fold enhancement in HeLa retention. Moreover, the PLGA-based capsules can respond RF field to trigger the entrapped DLM to generate solid-liquid-gas (SLG) tri-phase transformation for enhancing RF ablation and CPT release. Therefore, depending on the enhanced RF ablation and released CPT and the validated synergistic retention effect, the inhibitory outcome for tumor growth has gained an over 10-fold improvement, realizing RF ablation & chemotherapy synergistic treatment against HeLa solid tumor, which indicates a significant promise in clinical RF ablation.
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Affiliation(s)
- Kun Zhang
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China; Ultrasound Research and Education Institute, Tongji University School of Medicine, 301 Yan-hang-zhong Road, Shanghai, 200072, PR China
| | - Pei Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China; Ultrasound Research and Education Institute, Tongji University School of Medicine, 301 Yan-hang-zhong Road, Shanghai, 200072, PR China
| | - Yaping He
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China; Ultrasound Research and Education Institute, Tongji University School of Medicine, 301 Yan-hang-zhong Road, Shanghai, 200072, PR China
| | - Xiaowan Bo
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China
| | - Xiaolong Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China
| | - Dandan Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China
| | - Hangrong Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Ding-Xi Road, Shanghai, 200050, PR China.
| | - Huixiong Xu
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yan-chang-zhong Road, Shanghai, 200072, PR China; Ultrasound Research and Education Institute, Tongji University School of Medicine, 301 Yan-hang-zhong Road, Shanghai, 200072, PR China.
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Zhang K, Li P, Chen H, Bo X, Li X, Xu H. Continuous Cavitation Designed for Enhancing Radiofrequency Ablation via a Special Radiofrequency Solidoid Vaporization Process. ACS NANO 2016; 10:2549-2558. [PMID: 26800221 DOI: 10.1021/acsnano.5b07486] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Lowering power output and radiation time during radiofrequency (RF) ablation is still a challenge. Although it is documented that metal-based magnetothermal conversion and microbubbles-based inertial cavitation have been tried to overcome above issues, disputed toxicity and poor magnetothermal conversion efficiency for metal-based nanoparticles and violent but transient cavitation for microbubbles are inappropriate for enhancing RF ablation. In this report, a strategy, i.e., continuous cavitation, has been proposed, and solid menthol-encapsulated poly lactide-glycolide acid (PLGA) nanocapsules have been constructed, as a proof of concept, to validate the role of such a continuous cavitation principle in continuously enhancing RF ablation. The synthesized PLGA-based nanocapsules can respond to RF to generate menthol bubbles via distinctive radiofrequency solidoid vaporization (RSV) process, meanwhile significantly enhance ultrasound imaging for HeLa solid tumor, and further facilitate RF ablation via the continuous cavitation, as systematically demonstrated both in vitro and in vivo. Importantly, this RSV strategy can overcome drawbacks and limitations of acoustic droplet vaporization (ADV) and optical droplet vaporization (ODV), and will probably find broad applications in further cancer theranostics.
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Affiliation(s)
- Kun Zhang
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
- Ultrasound Research and Education Institute, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
| | - Pei Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
| | - Hangrong Chen
- State Key Laboratory of High Performance Ceramic and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Science , 1295 Ding-Xi Road, Shanghai 200050, P. R. China
| | - Xiaowan Bo
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
| | - Xiaolong Li
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
| | - Huixiong Xu
- Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
- Ultrasound Research and Education Institute, Tongji University School of Medicine , 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
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Vijayalaxmi, Cao Y, Scarfi MR. Adaptive response in mammalian cells exposed to non-ionizing radiofrequency fields: A review and gaps in knowledge. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2014; 760:S1383-5742(14)00004-0. [PMID: 24548818 DOI: 10.1016/j.mrrev.2014.02.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 02/03/2014] [Accepted: 02/06/2014] [Indexed: 11/19/2022]
Abstract
Adaptive response is a phenomenon in which cells which were pre-exposed to extremely low and non-toxic doses of a genotoxic agent became resistant to the damage induced by subsequent exposure to a higher and toxic dose of the same, similar (in action) or another genotoxic agent. Such response has been well documented in scientific literature in cells exposed in vitro and in vivo to low doses of physical (especially, ionizing radiation) and chemical mutagens. The existence of similar phenomenon in mammalian cells exposed in vitro and in vivo to non-ionizing radiofrequency fields has been reported in several research publications. In in vitro studies, human blood lymphocytes exposed to radiofrequency fields and then treated with a genotoxic mutagen or subjected to ionizing radiation showed significantly decreased genetic damage. Similar studies in tumor cells showed significantly increased viability, decreased apoptosis, increased mitochondrial membrane potential, decreased intracellular free Ca2+ and, increased Ca2+-Mg2+-ATPase activity. In in vivo studies, exposure of rodents to radiofrequency fields and then to lethal/sub-lethal doses of γ-radiation showed survival advantage, significantly decreased damage in hematopoietic tissues, decreased genetic damage in blood leukocytes and bone marrow cells, increased numbers of colony forming units in bone marrow, increased levels of colony stimulating factor and interleukin-3 in the serum and increased expression of genes related to cell cycle. These observations suggested the ability of radiofrequency fields to induce adaptive response and also indicated some potential mechanisms for the induction of such response. Several gaps in knowledge that need to be investigated were discussed.
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Atasoy HI, Gunal MY, Atasoy P, Elgun S, Bugdayci G. Immunohistopathologic demonstration of deleterious effects on growing rat testes of radiofrequency waves emitted from conventional Wi-Fi devices. J Pediatr Urol 2013; 9:223-9. [PMID: 22465825 DOI: 10.1016/j.jpurol.2012.02.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Accepted: 02/28/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To investigate effects on rat testes of radiofrequency radiation emitted from indoor Wi-Fi Internet access devices using 802.11.g wireless standards. METHODS Ten Wistar albino male rats were divided into experimental and control groups, with five rats per group. Standard wireless gateways communicating at 2.437 GHz were used as radiofrequency wave sources. The experimental group was exposed to radiofrequency energy for 24 h a day for 20 weeks. The rats were sacrificed at the end of the study. Intracardiac blood was sampled for serum 8-hydroxy-2'-deoxyguanosine levels. Testes were removed and examined histologically and immunohistochemically. Testis tissues were analyzed for malondialdehyde levels and prooxidant-antioxidant enzyme activities. RESULTS We observed significant increases in serum 8-hydroxy-2'-deoxyguanosine levels and 8-hydroxyguanosine staining in the testes of the experimental group indicating DNA damage due to exposure (p < 0.05). We also found decreased levels of catalase and glutathione peroxidase activity in the experimental group, which may have been due to radiofrequency effects on enzyme activity (p < 0.05). CONCLUSIONS These findings raise questions about the safety of radiofrequency exposure from Wi-Fi Internet access devices for growing organisms of reproductive age, with a potential effect on both fertility and the integrity of germ cells.
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Affiliation(s)
- Halil I Atasoy
- Departments of Pediatrics, Abant Izzet Baysal University School of Medicine, Bolu 14280, Turkey.
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Shahin S, Singh VP, Shukla RK, Dhawan A, Gangwar RK, Singh SP, Chaturvedi CM. 2.45 GHz microwave irradiation-induced oxidative stress affects implantation or pregnancy in mice, Mus musculus. Appl Biochem Biotechnol 2013; 169:1727-51. [PMID: 23334843 DOI: 10.1007/s12010-012-0079-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 12/27/2012] [Indexed: 12/17/2022]
Abstract
The present experiment was designed to study the 2.45 GHz low-level microwave (MW) irradiation-induced stress response and its effect on implantation or pregnancy in female mice. Twelve-week-old mice were exposed to MW radiation (continuous wave for 2 h/day for 45 days, frequency 2.45 GHz, power density=0.033549 mW/cm(2), and specific absorption rate=0.023023 W/kg). At the end of a total of 45 days of exposure, mice were sacrificed, implantation sites were monitored, blood was processed to study stress parameters (hemoglobin, RBC and WBC count, and neutrophil/lymphocyte (N/L) ratio), the brain was processed for comet assay, and plasma was used for nitric oxide (NO), progesterone and estradiol estimation. Reactive oxygen species (ROS) and the activities of ROS-scavenging enzymes- superoxide dismutase, catalase, and glutathione peroxidase-were determined in the liver, kidney and ovary. We observed that implantation sites were affected significantly in MW-irradiated mice as compared to control. Further, in addition to a significant increase in ROS, hemoglobin (p<0.001), RBC and WBC counts (p<0.001), N/L ratio (p<0.01), DNA damage (p<0.001) in brain cells, and plasma estradiol concentration (p<0.05), a significant decrease was observed in NO level (p<0.05) and antioxidant enzyme activities of MW-exposed mice. Our findings led us to conclude that a low level of MW irradiation-induced oxidative stress not only suppresses implantation, but it may also lead to deformity of the embryo in case pregnancy continues. We also suggest that MW radiation-induced oxidative stress by increasing ROS production in the body may lead to DNA strand breakage in the brain cells and implantation failure/resorption or abnormal pregnancy in mice.
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Affiliation(s)
- Saba Shahin
- Department of Zoology, Banaras Hindu University, Varanasi, 221005, India,
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Genetic damage in human cells exposed to non-ionizing radiofrequency fields: A meta-analysis of the data from 88 publications (1990–2011). MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2012; 749:1-16. [DOI: 10.1016/j.mrgentox.2012.09.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 09/16/2012] [Accepted: 09/17/2012] [Indexed: 01/12/2023]
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Zeni O, Sannino A, Romeo S, Massa R, Sarti M, Reddy AB, Prihoda TJ, Vijayalaxmi, Scarfì MR. Induction of an adaptive response in human blood lymphocytes exposed to radiofrequency fields: Influence of the universal mobile telecommunication system (UMTS) signal and the specific absorption rate. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2012; 747:29-35. [DOI: 10.1016/j.mrgentox.2012.03.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 01/02/2012] [Accepted: 03/20/2012] [Indexed: 01/18/2023]
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Abdollahi H, Teymouri M, Khademi S. Radiofrequency radiation may help astronauts in space missions. JOURNAL OF MEDICAL HYPOTHESES AND IDEAS 2012. [DOI: 10.1016/j.jmhi.2012.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Tsuji M, Yokoigawa K. Acid resistance and verocytotoxin productivity of enterohemorrhagic Escherichia coli O157:H7 exposed to microwave. J Food Sci 2012; 76:M445-9. [PMID: 22417515 DOI: 10.1111/j.1750-3841.2011.02225.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We examined the acid resistance and verocytotoxin (VT) productivity of enterohemorrhagic Escherichia coli O157:H7 irradiated by microwave with a domestic microwave oven and a commercial microwave radiator equipped with a thermo-regulator. When the cell suspension (5 mL) chilled at 0 °C was treated with a domestic microwave oven at weak power (2.45 GHz, 100 W) for 60 s, the living cell number was reduced by 2 orders (final temperature, about 65 °C). The surviving cells showed lower acid resistance and VT productivity than nonirradiated cells. To examine the nonthermal effect of microwave on acid resistance and VT productivity, the cells in Luria-Bertani medium were intermittently irradiated to keep the culture temperature at 37 °C with the microwave radiator (2.45 GHz, 0.6 W/mL). The intermittent radiation slightly reduced the acid resistance, but clearly suppressed the VT productivity. Microwave oven is probably useful for reducing not only the living cell number but also the acid resistance and VT productivity of EHEC O157:H7.
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Affiliation(s)
- Makiko Tsuji
- Dept. of Life Science, Graduate School of Integrated Arts and Sciences, Univ. of Tokushima, 1-1 Minamijosanjima-cho, Tokushima 770-8502, Japan
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Jiang B, Nie J, Zhou Z, Zhang J, Tong J, Cao Y. Adaptive response in mice exposed to 900 MHz radiofrequency fields: primary DNA damage. PLoS One 2012; 7:e32040. [PMID: 22389679 PMCID: PMC3289639 DOI: 10.1371/journal.pone.0032040] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 01/18/2012] [Indexed: 11/20/2022] Open
Abstract
The phenomenon of adaptive response (AR) in animal and human cells exposed to ionizing radiation is well documented in scientific literature. We have examined whether such AR could be induced in mice exposed to non-ionizing radiofrequency fields (RF) used for wireless communications. Mice were pre-exposed to 900 MHz RF at 120 µW/cm(2) power density for 4 hours/day for 1, 3, 5, 7 and 14 days and then subjected to an acute dose of 3 Gy γ-radiation. The primary DNA damage in the form of alkali labile base damage and single strand breaks in the DNA of peripheral blood leukocytes was determined using the alkaline comet assay. The results indicated that the extent of damage in mice which were pre-exposed to RF for 1 day and then subjected to γ-radiation was similar and not significantly different from those exposed to γ-radiation alone. However, mice which were pre-exposed to RF for 3, 5, 7 and 14 days showed progressively decreased damage and was significantly different from those exposed to γ-radiation alone. Thus, the data indicated that RF pre-exposure is capable of inducing AR and suggested that the pre-exposure for more than 4 hours for 1 day is necessary to elicit such AR.
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Affiliation(s)
| | | | | | | | | | - Yi Cao
- School of Public Health, Soochow University, Suzhou, Jiangsu, People's Republic of China
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17
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[What is a "poison"? Proposal of definition]. Med Clin (Barc) 2012; 138:127-32. [PMID: 21453940 DOI: 10.1016/j.medcli.2011.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 01/31/2011] [Accepted: 02/01/2011] [Indexed: 11/22/2022]
Abstract
We discuss different interpretations of the term poison as well as the need of bringing up to date the changes in this matter according to the science progress. A clear and exact definition is proposed after analysing the factors that affect the relativity of the concept and its boundaries. The proposal for a definition is presented taking into account the most broadly extended concepts concerning its significance. That is to say: "a poison is, for human beings and their non-pathogenic and non-harmful biological environment, an electromagnetic or corpuscular radiation, or a non-infectious chemical agent, structured no larger in size than a small particle or fibre that, after being generated internally or after contact, penetration and/or absorption by a live organism, in sufficiently high dose, can produce or produces a direct or indirect adverse effect unrelated to its temperature or measurable electrical potential difference". The scientific knowledge needs accurate definitions to avoid ambiguities.
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Guo L, Kubat NJ, Isenberg RA. Pulsed radio frequency energy (PRFE) use in human medical applications. Electromagn Biol Med 2011; 30:21-45. [DOI: 10.3109/15368378.2011.566775] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Chaturvedi CM, Singh VP, Singh P, Basu P, Singaravel M, Shukla RK, Dhawan A, Pati AK, Gangwar RK, Singh SP. 2.45 GHz (CW) MICROWAVE IRRADIATION ALTERS CIRCADIAN ORGANIZATION, SPATIAL MEMORY, DNA STRUCTURE IN THE BRAIN CELLS AND BLOOD CELL COUNTS OF MALE MICE, MUS MUSCULUS. ACTA ACUST UNITED AC 2011. [DOI: 10.2528/pierb11011205] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Impact of 1.8-GHz radiofrequency radiation (RFR) on DNA damage and repair induced by doxorubicin in human B-cell lymphoblastoid cells. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2010; 695:16-21. [DOI: 10.1016/j.mrgentox.2009.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 09/14/2009] [Accepted: 10/03/2009] [Indexed: 11/20/2022]
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21
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Gapeyev AB, Mikhailik EN, Chemeris NK. Features of anti-inflammatory effects of modulated extremely high-frequency electromagnetic radiation. Bioelectromagnetics 2009; 30:454-61. [PMID: 19431156 DOI: 10.1002/bem.20499] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Using a model of acute zymosan-induced paw edema in NMRI mice, we test the hypothesis that anti-inflammatory effects of extremely high-frequency electromagnetic radiation (EHF EMR) can be essentially modified by application of pulse modulation with certain frequencies. It has been revealed that a single exposure of animals to continuous EHF EMR for 20 min reduced the exudative edema of inflamed paw on average by 19% at intensities of 0.1-0.7 mW/cm(2) and frequencies from the range of 42.2-42.6 GHz. At fixed effective carrier frequency of 42.2 GHz, the anti-inflammatory effect of EHF EMR did not depend on modulation frequencies, that is, application of different modulation frequencies from the range of 0.03-100 Hz did not lead to considerable changes in the effect level. On the contrary, at "ineffective" carrier frequencies of 43.0 and 61.22 GHz, the use of modulation frequencies of 0.07-0.1 and 20-30 Hz has allowed us to restore the effect up to a maximal level. The results obtained show the critical dependence of anti-inflammatory action of low-intensity EHF EMR on carrier and modulation frequencies. Within the framework of this study, the possibility of changing the level of expected biological effect of modulated EMR by a special selection of combination of carrier and modulation frequencies is confirmed.
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Affiliation(s)
- Andrew B Gapeyev
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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22
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Sannino A, Sarti M, Reddy SB, Prihoda TJ, Vijayalaxmi, Scarfì MR. Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation. Radiat Res 2009; 171:735-42. [PMID: 19580480 DOI: 10.1667/rr1687.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.
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Affiliation(s)
- Anna Sannino
- CNR-Institute for Electromagnetic Sensing of Environment, Napoli, Italy
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Rağbetli MÇ, Aydinlioğlu A, Koyun N, Rağbetli C, Karayel M. Effect of Prenatal Exposure to Mobile Phone on Pyramidal Cell Numbers in the Mouse Hippocampus: A Stereological Study. Int J Neurosci 2009; 119:1031-41. [DOI: 10.1080/00207450802324812] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Juutilainen J, Heikkinen P, Soikkeli H, Mäki-Paakkanen J. Micronucleus frequency in erythrocytes of mice after long-term exposure to radiofrequency radiation. Int J Radiat Biol 2009; 83:213-20. [PMID: 17575948 DOI: 10.1080/09553000601169800] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE The aim of the study was to investigate genotoxicity of long-term exposure to radiofrequency (RF) electromagnetic fields by measuring micronuclei in erythrocytes. The blood samples were collected in two animal studies evaluating possible cocarcinogenic effects of RF fields. METHODS In study A, female CBA/S mice were exposed for 78 weeks (1.5 h/d, 5 d/week) to either a continuous 902.5 MHz signal similar to that emitted by analog NMT (Nordic Mobile Telephone) phones at a whole-body specific absorption rate (SAR) of 1.5 W/kg, or to a pulsed 902.4 MHz signal similar to that of digital GSM (Global System for Mobile Communications) phones at 0.35 W/kg. A third group was sham-exposed, and a fourth group served as cage controls. All but the cage control animals were exposed to 4 Gy of x-rays during three first weeks of the experiment. In study B, female transgenic mice (line K2) and their nontransgenic littermates were exposed for 52 weeks (1.5 h/d, 5 d/week). Two digital mobile phone signals, GSM and DAMPS (Digital Advanced Mobile Phone System), were used at 0.5 W/kg. All but the cage-control animals were exposed 3 times per week to an ultraviolet radiation dose of 1.2 MED (minimum erythema dose). RESULTS AND CONCLUSIONS The results did not show any effects of RF fields on micronucleus frequency in polychromatic or normochromatic erythrocytes. The results were consistent in two mouse strains (and in a transgenic variant of the second strain), after 52 or 78 weeks of exposure, at three SAR levels relevant to human exposure from mobile phones, and for three different mobile signals.
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Affiliation(s)
- Jukka Juutilainen
- Department of Environmental Sciences, University of Kuopio, Kuopio, Finland.
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25
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Zhijian C, Xiaoxue L, Yezhen L, Deqiang L, Shijie C, Lifen J, Jianlin L, Jiliang H. Influence of 1.8-GHz (GSM) radiofrequency radiation (RFR) on DNA damage and repair induced by X-rays in human leukocytes in vitro. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2009; 677:100-4. [DOI: 10.1016/j.mrgentox.2009.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 05/18/2009] [Accepted: 05/24/2009] [Indexed: 11/25/2022]
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Höytö A, Luukkonen J, Juutilainen J, Naarala J. Proliferation, oxidative stress and cell death in cells exposed to 872 MHz radiofrequency radiation and oxidants. Radiat Res 2008; 170:235-43. [PMID: 18666817 DOI: 10.1667/rr1322.1] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Accepted: 03/12/2008] [Indexed: 11/03/2022]
Abstract
Human SH-SY5Y neuroblastoma and mouse L929 fibroblast cells were exposed to 872 MHz radiofrequency (RF) radiation using continuous waves (CW) or a modulated signal similar to that emitted by GSM mobile phones at a specific absorption rate (SAR) of 5 W/kg in isothermal conditions. To investigate possible combined effects with other agents, menadione was used to induce reactive oxygen species, and tert-butylhydroperoxide (t-BOOH) was used to induce lipid peroxidation. After 1 or 24 h of exposure, reduced cellular glutathione levels, lipid peroxidation, proliferation, caspase 3 activity, DNA fragmentation and viability were measured. Two statistically significant differences related to RF radiation were observed: Lipid peroxidation induced by t-BOOH was increased in SH-SY5Y (but not in L929) cells, and menadione-induced caspase 3 activity was increased in L929 (but not in SH-SY5Y) cells. Both differences were statistically significant only for the GSM-modulated signal. The other end points were not significantly affected in any of the experimental conditions, and no effects were observed from exposure to RF radiation alone. The positive findings may be due to chance, but they may also reflect effects that occur only in cells sensitized by chemical stress. Further studies are required to investigate the reproducibility and dose response of the possible effects.
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Affiliation(s)
- Anne Höytö
- Department of Environmental Science, Bioteknia 2, University of Kuopio, Kuopio, Finland.
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27
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Vijayalaxmi, Prihoda TJ. Genetic Damage in Mammalian Somatic Cells Exposed to Radiofrequency Radiation: A Meta-analysis of Data from 63 Publications (1990–2005). Radiat Res 2008; 169:561-74. [DOI: 10.1667/rr0987.1] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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28
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Manti L, Braselmann H, Calabrese ML, Massa R, Pugliese M, Scampoli P, Sicignano G, Grossi G. Effects of Modulated Microwave Radiation at Cellular Telephone Frequency (1.95 GHz) on X-Ray-Induced Chromosome Aberrations in Human LymphocytesIn Vitro. Radiat Res 2008; 169:575-83. [DOI: 10.1667/rr1044.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Accepted: 01/18/2008] [Indexed: 11/03/2022]
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Schmid G, Uberbacher R, Samaras T, Tschabitscher M, Mazal PR. The dielectric properties of human pineal gland tissue and RF absorption due to wireless communication devices in the frequency range 400–1850 MHz. Phys Med Biol 2007; 52:5457-68. [PMID: 17762098 DOI: 10.1088/0031-9155/52/17/024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In order to enable a detailed analysis of radio frequency (RF) absorption in the human pineal gland, the dielectric properties of a sample of 20 freshly removed pineal glands were measured less than 20 h after death. Furthermore, a corresponding high resolution numerical model of the brain region surrounding the pineal gland was developed, based on a real human tissue sample. After inserting this model into a commercially available numerical head model, FDTD-based computations for exposure scenarios with generic models of handheld devices operated close to the head in the frequency range 400-1850 MHz were carried out. For typical output power values of real handheld mobile communication devices, the obtained results showed only very small amounts of absorbed RF power in the pineal gland when compared to SAR limits according to international safety standards. The highest absorption was found for the 400 MHz irradiation. In this case the RF power absorbed inside the pineal gland (organ mass 96 mg) was as low as 11 microW, when considering a device of 500 mW output power operated close to the ear. For typical mobile phone frequencies (900 MHz and 1850 MHz) and output power values (250 mW and 125 mW) the corresponding values of absorbed RF power in the pineal gland were found to be lower by a factor of 4.2 and 36, respectively. These results indicate that temperature-related biologically relevant effects on the pineal gland induced by the RF emissions of typical handheld mobile communication devices are unlikely.
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Affiliation(s)
- Gernot Schmid
- Austrian Research Centers GmbH-ARC, ITM, A-2444 Seibersdorf, Austria.
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Krewski D, Glickman BW, Habash RWY, Habbick B, Lotz WG, Mandeville R, Prato FS, Salem T, Weaver DF. Recent advances in research on radiofrequency fields and health: 2001-2003. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2007; 10:287-318. [PMID: 17620203 DOI: 10.1080/15287390600974973] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The widespread use of wireless telecommunications devices, particularly mobile phones, has resulted in increased human exposure to radiofrequency (RF) fields. Although national and international agencies have established safety guidelines for exposure to RF fields, concerns remain about the potential for adverse health outcomes to occur in relation to RF field exposure. The extensive literature on RF fields and health has been reviewed by a number of authorities, including the Royal Society of Canada (1999), the European Commission's Scientific Committee on Toxicity, Ecotoxicity, and the Environment (CSTEE, 2001), the British Medical Association (2001), the Swedish Radiation Protection Authority (Boice & McLaughlin, 2002), and the Health Council of The Netherlands (2002). This report provides an update on recent research results on the potential health risks of RF fields since the publication of the Royal Society of Canada report in 1999 (See Krewski et al., 2001a) and our previous 2001 update (Krewski et al., 2001b), covering the period 2001-2003. The present report examines new data on dosimetry and exposure assessment, biological effects such as enzyme induction, and toxicological effects, including genotoxicity, carcinogenicity, and testicular and reproductive outcomes. Epidemiological studies of mobile phone users and occupationally exposed populations are examined, along with human and animal studies of neurological and behavioral effects. All of the authoritative reviews completed within the last 2 yr have concluded that there is no clear evidence of adverse health effects associated with RF fields. However, following a recent review of nine epidemiological studies of mobile phones and cancer, Kundi et al. (2004) concluded that the possibility of an enhanced cancer risk cannot be excluded. These same reviews support the need for further research to clarify the possible associations between RF fields and adverse health outcomes that have appeared in some reports. The results of the ongoing World Health Organization (WHO) study of mobile phones will provide important new information in this regard.
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Affiliation(s)
- Daniel Krewski
- R. Samuel McLaughlin Center for Population Health Risk Assessment, University of Ottawa, Ottawa, Ontario, Canada.
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D'Andrea JA, Ziriax JM, Adair ER. Radio frequency electromagnetic fields: mild hyperthermia and safety standards. PROGRESS IN BRAIN RESEARCH 2007; 162:107-35. [PMID: 17645917 DOI: 10.1016/s0079-6123(06)62007-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This chapter is a short review of literature that serves as the basis for current safe exposure recommendations by ICNIRP (International Commission on Non-Ionizing Radiation Protection, 1998). and the IEEE C95.1 (IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz, 2005) for exposure to radio frequency electromagnetic radiation (RF-EMF). Covered here are topics on dosimetry, thermoregulatory responses, behavioral responses, and how these have been used to derive safe exposure limits for humans to RF-EMF. Energy in this portion of the electromagnetic spectrum, 3 kHz-300 GHz, can be uniquely absorbed and is different from ionizing radiation both in dosimetry and effects. The deposition of thermalizing energy deep in the body by exposure to RF-EMF fields provides a unique exception to the energy flows normally encountered by humans. Behavioral effects of RF-EMF exposure range from detection to complete cessation of trained behaviors. RF-EMF is detectable and can in most cases, presumably by thermal mechanisms, support aversion and disruption or complete cessation (work stoppage) of behavior. Safety standards are based on behavioral responses by laboratory animals to RF-EMF, enhanced by careful studies of human thermoregulatory responses at four specific RF frequencies, thereby providing a conservative level of protection from RF-EMF for humans.
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Affiliation(s)
- John A D'Andrea
- Directed Energy Bioeffects Laboratory, Naval Health Research Center Detachment, 8315 Navy Road, Brooks City-Base, TX 78235, USA.
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Koyama S, Takashima Y, Sakurai T, Suzuki Y, Taki M, Miyakoshi J. Effects of 2.45 GHz electromagnetic fields with a wide range of SARs on bacterial and HPRT gene mutations. JOURNAL OF RADIATION RESEARCH 2007; 48:69-75. [PMID: 17179647 DOI: 10.1269/jrr.06085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Present day use of mobile phones is ubiquitous. This causes some concern for human health due to exposure to high-frequency electromagnetic fields (HFEMF) from mobile phones. Consequently, we have examined the effects of 2.45 GHz electromagnetic fields on bacterial mutations and the hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene mutations. Using the Ames test, bacteria were exposed to HFEMF for 30 min at specific absorption rates (SARs) from 5 to 200 W/kg. In all strains, there was no significant difference in the frequency of revertant colonies between sham exposure and HFEMF-exposed groups. In examination of mutations of the HPRT gene, Chinese hamster ovary (CHO)-K1 cells were exposed to HFEMF for 2 h at SARs from 5 to 200 W/kg. We detected a combination effect of simultaneous exposure to HFEMF and bleomycin at the respective SARs. A statistically significant difference was observed between the cells exposed to HFEMF at the SAR of 200 W/kg. Cells treated with the combination of HFEMF at SARs from 50 to 200 W/kg and bleomycin exhibited increased HPRT mutations. As the exposure to HFEMF induced an increase in temperature, these increases of mutation frequency may be a result of activation of bleomycin by heat. We consider that the increase of mutation frequency may be due to a thermal effect.
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Affiliation(s)
- Shin Koyama
- Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Hirosaki University, Japan
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Zeng Q, Chen G, Weng Y, Wang L, Chiang H, Lu D, Xu Z. Effects of Global System for Mobile Communications 1800 MHz radiofrequency electromagnetic fields on gene and protein expression in MCF-7 cells. Proteomics 2006; 6:4732-8. [PMID: 16888767 DOI: 10.1002/pmic.200600234] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Despite many studies over a decade, it still remains ambiguous as to the real biological effects induced by radiofrequency electromagnetic fields (RF EMF) utilized in mobile telephony. Here we investigated global gene and protein responses to RF EMF simulating the Global System for Mobile Communications (GSM) 1800 MHz signal in human breast cancer cell line MCF-7 using genomic and proteomic approaches. GeneChip analysis identified a handful of consistent changed genes after exposure to RF EMF at specific absorption rates (SAR) of up to 3.5 W/kg for 24 h. However, these differentially transcribed genes could not be further confirmed by real-time RT-PCR assay. Meanwhile, systematic proteome analysis of the MCF-7 cells revealed that a few but different proteins were differentially expressed under continuous or intermittent RF EMF exposure at SAR of 3.5 W/kg for 24 h or less, implying that the observed effects might have occurred by chance. Overall, the present study does not provide convincing evidence that RF EMF exposure under current experimental conditions can produce distinct effects on gene and protein expression in the MCF-7 cells.
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Affiliation(s)
- Qunli Zeng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
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Cytogenetic Studies in Human Blood Lymphocytes ExposedIn Vitroto 2.45 GHz or 8.2 GHz Radiofrequency Radiation. Radiat Res 2006; 166:532-8. [PMID: 16972753 DOI: 10.1667/rr0643.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 05/16/2006] [Indexed: 11/03/2022]
Abstract
Peripheral blood samples collected from healthy human volunteers were exposed in vitro to 2.45 GHz or 8.2 GHz pulsed-wave radiofrequency (RF) radiation. The net forward power, average power density, mean specific absorption rate, and the temperature maintained during the 2-h exposure of the cells to 2.45 GHz or 8.2 GHz were, respectively, 21 W or 60 W, 5 mW/cm(2) or 10 mW/cm(2), 2.13 W/kg or 20.71 W/kg, and 36.9 +/- 0.1 degrees C or 37.5 +/- 0.2 degrees C. Aliquots of the same blood samples that were either sham-exposed or exposed in vitro to an acute dose of 1.5 Gy gamma radiation were used as unexposed and positive controls, respectively. Cultured lymphocytes were examined to determine the extent of cytogenetic damage assessed from the incidence of chromosomal aberrations and micronuclei. Under the conditions used to perform the experiments, the levels of damage in RF-radiation-exposed and sham-exposed lymphocytes were not significantly different. Also, there were no significant differences in the response of unstimulated lymphocytes and lymphocytes stimulated with phytohemagglutinin when exposed to 8.2 GHz RF radiation. In contrast, the positive control cells that had been subjected to gamma irradiation exhibited significantly more damage than RF-radiation- and sham-exposed lymphocytes.
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Takashima Y, Hirose H, Koyama S, Suzuki Y, Taki M, Miyakoshi J. Effects of continuous and intermittent exposure to RF fields with a wide range of SARs on cell growth, survival, and cell cycle distribution. Bioelectromagnetics 2006; 27:392-400. [PMID: 16615058 DOI: 10.1002/bem.20220] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To examine the biological effects of radio frequency (RF) electromagnetic fields in vitro, we have examined the fundamental cellular responses, such as cell growth, survival, and cell cycle distribution, following exposure to a wide range of specific absorption rates (SAR). Furthermore, we compared the effects of continuous and intermittent exposure at high SARs. An RF electromagnetic field exposure unit operating at a frequency of 2.45 GHz was used to expose cells to SARs from 0.05 to 1500 W/kg. When cells were exposed to a continuous RF field at SARs from 0.05 to 100 W/kg for 2 h, cellular growth rate, survival, and cell cycle distribution were not affected. At 200 W/kg, the cell growth rate was suppressed and cell survival decreased. When the cells were exposed to an intermittent RF field at 300 W/kg(pk), 900 W/kg(pk) and 1500 W/kg(pk) (100 W/kg(mean)), no significant differences were observed between these conditions and intermittent wave exposure at 100 W/kg. When cells were exposed to a SAR of 50 W/kg for 2 h, the temperature of the medium around cells rose to 39.1 degrees C, 100 W/kg exposure increased the temperature to 41.0 degrees C, and 200 W/kg exposure increased the temperature to 44.1 degrees C. Exposure to RF radiation results in heating of the medium, and the thermal effect depends on the mean SAR. Hence, these results suggest that the proliferation disorder is caused by the thermal effect.
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Affiliation(s)
- Yoshio Takashima
- Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Hirosaki University, Hirosaki, Japan
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Heikkinen P, Ernst H, Huuskonen H, Komulainen H, Kumlin T, Mäki-Paakkanen J, Puranen L, Juutilainen J. No Effects of Radiofrequency Radiation on 3-Chloro-4-(dichloromethyl)-5-hydroxy-2( 5H)-furanone-Induced Tumorigenesis in Female Wistar Rats. Radiat Res 2006; 166:397-408. [PMID: 16881741 DOI: 10.1667/rr3588.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This study evaluated possible effects of radiofrequency (RF) radiation on tumorigenesis induced by the mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) given in drinking water. Female Wistar rats aged 7 weeks at the beginning of the experiments were randomly divided into four groups of 72 animals: a cage-control group and three MX-exposed groups (a daily average dose of 1.7 mg MX/kg body weight for 104 weeks), of which two were exposed to 900 MHz pulsed RF radiation and the third served as a sham-RF-radiation group. The RF-radiation groups were exposed 2 h per day, 5 days per week for 104 weeks at nominal whole-body average SARs of 0.3 W/kg and 0.9 W/kg. Complete histopathology was performed on the rats of the three MX-exposed groups. The tumor types and incidences observed in the MX-exposed animals were similar to those reported earlier in MX-exposed female Wistar rats. RF radiation did not statistically significantly affect mortality or organ-specific incidence of any tumor type. The only statistically significant difference was an increase in the combined frequency of vascular tumors of the mesenteric lymph nodes in the high-RF-radiation group compared to the sham-RF-radiation group. However, additional histopathological analysis of the cage-control animals suggested that this difference was due to unusually low frequency of this type of tumor in the sham-RF-radiation group rather than a high frequency in the high-RF-radiation group. With respect to non-neoplastic findings, statistically significant differences between the RF-radiation groups and the sham-RF-radiation group were observed only for single findings in the lacrimal glands, lungs, liver and skin. Such changes are commonly seen in aged rats and were considered to be unrelated to RF radiation. The results of the present study do not support co-carcinogenic effects of low-level long-term RF-radiation exposure in rats.
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Affiliation(s)
- Päivi Heikkinen
- University of Kuopio, Department of Environmental Sciences, Kuopio, Finland.
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Nasta F, Prisco MG, Pinto R, Lovisolo GA, Marino C, Pioli C. Effects of GSM-Modulated Radiofrequency Electromagnetic Fields on B-Cell Peripheral Differentiation and Antibody Production. Radiat Res 2006; 165:664-70. [PMID: 16802866 DOI: 10.1667/rr3555.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We examined the effects of in vivo exposure to a GSM-modulated 900 MHz RF field on B-cell peripheral differentiation and antibody production in mice. Our results show that exposure to a whole-body average specific absorption rate (SAR) of 2 W/kg, 2 h/day for 4 consecutive weeks does not affect the frequencies of differentiating transitional 1 (T1) and T2 B cells or those of mature follicular B and marginal zone B cells in the spleen. IgM and IgG serum levels are also not significantly different among exposed, sham-exposed and control mice. B cells from these mice, challenged in vitro with LPS, produce comparable amounts of IgM and IgG. Moreover, exposure of immunized mice to RF fields does not change the antigen-specific antibody serum level. Interestingly, not only the production of antigen-specific IgM but also that of IgG (which requires T-B-cell interaction) is not affected by RF-field exposure. This indicates that the exposure does not alter an ongoing in vivo antigen-specific immune response. In conclusion, our results do not indicate any effects of GSM-modulated RF radiation on the B-cell peripheral compartment and antibody production and thus provide no support for health-threatening effects.
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Affiliation(s)
- Francesca Nasta
- ENEA (Italian Agency for New Technologies, Environment and Energy), Section of Toxicology and Biomedicine, Rome, Italy
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Paulraj R, Behari J. Single strand DNA breaks in rat brain cells exposed to microwave radiation. Mutat Res 2006; 596:76-80. [PMID: 16458332 DOI: 10.1016/j.mrfmmm.2005.12.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2005] [Revised: 12/09/2005] [Accepted: 12/22/2005] [Indexed: 04/26/2023]
Abstract
This investigation concerns with the effect of low intensity microwave (2.45 and 16.5 GHz, SAR 1.0 and 2.01 W/kg, respectively) radiation on developing rat brain. Wistar rats (35 days old, male, six rats in each group) were selected for this study. These animals were exposed for 35 days at the above mentioned frequencies separately in two different exposure systems. After the exposure period, the rats were sacrificed and the whole brain tissue was dissected and used for study of single strand DNA breaks by micro gel electrophoresis (comet assay). Single strand DNA breaks were measured as tail length of comet. Fifty cells from each slide and two slides per animal were observed. One-way ANOVA method was adopted for statistical analysis. This study shows that the chronic exposure to these radiations cause statistically significant (p<0.001) increase in DNA single strand breaks in brain cells of rat.
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Affiliation(s)
- R Paulraj
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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Abstract
OBJECTIVE We sought to examine the impact of occupational exposure on brain cancer risk. METHODS Mailed questionnaires were used to collect information on lifetime employment history, occupational exposure to 18 chemicals, and other risk factors for 1009 incident cases of brain cancer and 5039 control subjects in Canada in 1994 to 1997. RESULTS People exposed to asphalt and welding had respective odds ratio (and 95% confidence interval) of 1.29 (1.02-1.62) and 1.26 (0.98-1.45). An increased risk of brain cancer might be associated with exposure to asbestos, benzene, mineral or lubricating oil, isopropyl oil, and wood dust and with following occupations: teaching; protective service; metal processing and related jobs, and metal shaping and forming; knitting in textile processing; construction trades; and transport equipment operating. CONCLUSIONS Our study suggests a possible role for occupational exposure in the etiology of brain cancer.
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Affiliation(s)
- Sai Yi Pan
- Surveillance and Risk Assessment Division, Centre for Chronic Disease Prevention and Control, Public Health Agency of Canada, Ottawa, Ontario, Canada
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Abstract
The rapidly evolving mobile phone technology raised public concern about the possibility of associated adverse health effects. The current body of evidence is summarized addressing epidemiological studies, studies investigating adverse biological effects, other biological effects, basic mechanisms and indirect effects. Currently, the balance of evidence from epidemiological studies suggests that there is no association between mobile phone radiation and cancer. This finding is consistent with experimental results. There is some evidence for biological effects, which, however, are not necessarily hazardous for humans. No basic mechanisms of biological effects have been consistently identified yet. Using a mobile phone while driving a car is significantly associated with a higher risk of vehicle collisions, independently of the use of hands-free kits. Medical equipment or implanted pacemakers may be affected by mobile phone radiation under very specific conditions. Current studies, however are affected by several limitations and do not generally exclude any increased health risk. Further high-quality research is therefore necessary. Furthermore, it is important that the results of scientific research are communicated to the public in a transparent and differentiated way.
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Affiliation(s)
- Christian P Karger
- Deutsches Krebsforschungszentrum, Abteilung Medizinische Physik in der Strahlentherapie, Heidelberg.
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Trosic I, Busljeta I, Pavicic I. Blood-forming system in rats after whole-body microwave exposure; reference to the lymphocytes. Toxicol Lett 2004; 154:125-32. [PMID: 15475186 DOI: 10.1016/j.toxlet.2004.07.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2004] [Revised: 07/14/2004] [Accepted: 07/20/2004] [Indexed: 11/19/2022]
Abstract
The influence of 2.45 GHz microwave (RF/MW) irradiation on blood-forming cells after whole-body irradiation of rats was investigated. The exposures were conducted with a field power density of 5-10 mW/cm2, and whole-body average specific absorption rate (SAR) of 1-2 W/kg. Four experimental subgroups were created and irradiated 2, 8, 15 or 30 days, for 2 h a day, 7 days a week. Concurrent sham-exposed rats were also included in the study. The cell response was assessed by number and type of the bone marrow nuclear cells and peripheral blood white cells using standard laboratory methods. Significant decrease in lymphoblast count was obtained at 15 and 30th experimental day (P < 0.05), whereas other examined parameters did not significantly differed in comparison to the sham-exposed controls. The findings point out at stress response in blood-forming system in rats after selected microwave exposure, which could be considered rather as sign of adaptation than malfunction.
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Affiliation(s)
- Ivancica Trosic
- Department of Radiology, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, HR-10000 Zagreb, Croatia.
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Obe G. Controversial Cytogenetic Observations in Mammalian Somatic Cells Exposed to Radiofrequency Radiation. Radiat Res 2004; 162:481-96. [PMID: 15624303 DOI: 10.1667/rr3252] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
During the years 1990-2003 a large number of investigations were conducted using rodents, cultured rodent and human cells, and freshly collected human blood lymphocytes to determine the genotoxic potential of exposure to radiofrequency (RF) radiation. The results of most of these studies (58%) did not indicate increased damage to the genetic material (assessed from DNA strand breaks, incidence of chromosomal aberrations, micronuclei and sister chromatid exchanges) in cells exposed to RF radiation compared to sham-exposed and/or unexposed cells. Some investigations (23%) reported an increase in such damage in cells exposed to RF radiation. The observations from other studies (19%) were inconclusive. This paper reviews the investigations published in scientific journals during 1990-2003 and attempts to identify probable reason(s) for the conflicting results. Recommendations are made for future research to address some of the controversial observations.
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Elder JA. Survival and cancer in laboratory mammals exposed to radiofrequency energy. Bioelectromagnetics 2004; Suppl 6:S101-6. [PMID: 14628309 DOI: 10.1002/bem.10175] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This article is a review of the effects of radiofrequency (RF) energy on (1). survival and (2). cancer in the same animal populations having survival data. The literature consisted of 18 studies with survival data, and 16 of these have information on cancer. In one study, a significant decrease in lifespan was observed at 6.8 W/kg but not at 2 W/kg. Thermal stress appears to be the causal factor for the effect on lifespan because the higher dose rate, unlike the lower dose rate, was estimated to increase body temperature significantly. The finding that the lower level was without effect is consistent with the results of a number of recent studies showing that long term, low level exposure to RF energy did not affect survival adversely. Many of these recent studies addressed the cancer issue by histopathological analysis of many organs and tissues following exposure up to 2 years, the average lifetime of rats and mice. Some investigations examined the effect of RF fields from mobile phones on brain cancer, including the progression of chemically induced brain cancer. The results demonstrate that RF exposure did not adversely affect cancer incidence at whole body specific absorption rates (SARs) <or=4 W/kg and brain SARs <or=2.3 W/kg. The weight-of-evidence of these 18 studies shows that long term, low level exposure to RF energy does not adversely affect survival and cancer in laboratory mammals.
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Affiliation(s)
- Joe A Elder
- Motorola Florida Research Laboratories, Ft Lauderdale, Florida 33322, USA.
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