The latest additions appear below. The complete collection of abstracts now covers more than 1,300 scientific papers. This 1,048-page document (pdf) can be downloaded by clicking on the following link:
Romualdo Sciorio, Luca Tramontano, Sandro C Esteves. Effects of mobile phone radiofrequency radiation on sperm quality. Zygote. 2021 Aug 13;1-10. doi: 10.1017/S096719942100037X
In the last decades, the universal use of mobile phones has contributed to radiofrequency electromagnetic radiation environmental pollution. The steady growth in mobile phone usage has raised concerns about the effects of phone radiation on male reproductive health. Epidemiological studies report a sharp decline in sperm counts in developing countries, and worldwide with c. 14% of couples having difficulties to conceive, many of which are attributed to a male infertility factor. Environment and lifestyle factors are known to contribute to male infertility. Exposure to heat, radiation, or radioactivity might induce damage to biological tissue organs, including the testis. Given the ubiquitous use of mobile phones, the potential adverse effects of the resulting environmental radiation needs to be elucidated further. It seems to be an apparent relationship between the increased exposure to mobile phone radiofrequency and sperm quality decline, but the evidence is not conclusive. Our review summarizes the evidence concerning the possible adverse effects of cell phone radiation on the male reproductive system, with a focus on sperm quality. Also, we critically analyze the effects of elevated testicular temperature and oxidative stress on male fertility and how these factors could interfere with the physiological activities of the testis.
The exact mechanisms of how RF-EMR might affect the testis, epididymis, and sperm have not yet been fully understood. Additional studies are warranted, particularly prospective studies assessing sperm functional markers, such as sperm DNA integrity and OS, in fertile and subfertile men. Equally important will be to analyze whether the decreased sperm quality associated with mobile phone exposure translates into impaired pregnancy chances. The effects of short-term and long-term exposure and energy intensity should be also investigated in more detail, taking into account relevant confounders. Only then will scientific societies and regulatory bodies be able to provide users with transparent information concerning the risks and guidance for proper use.
Threshold of radiofrequency electromagnetic field effect on human brain (review)
Hiie Hinrikus, Jaanus Lass, Maie Bachmann. Threshold of radiofrequency electromagnetic field effect on human brain. Int J Radiat Biol. 2021 Aug 17;1-38. doi: 10.1080/09553002.2021.1969055.
Purpose: This review aims to estimate the threshold of radiofrequency electromagnetic field (RF EMF) effects on human brain based on analyses of published research results. To clarify the threshold of the RF EMF effects, two approaches have been applied: 1) the analyses of restrictions in sensitivity for different steps of the physical model of low-level RF EMF mechanism and 2) the analyses of experimental data to clarify the dependence of the RF EMF effect on exposure level based on the results of published original neurophysiological and behavioral human studies for 15 years 2007-2021.
Does the RF EMF has a threshold, lower of which the RF EMF does not have biological effect? This is an important question and crucial to avoid possible consequences on health.
Theoretical estimations for the sensitivity of living cells to electric field provided the threshold values about 10−6 - 10 −7 V/m Hz1/2 (Weaver and Astumian, 1990; Hinrikus et al., 1998). In the case of wide-band telecommunication technology, the threshold rises: at 1 MHz bandwidth, the sensitivity is 10−3 - 10 −4 V/m. However, these estimations used a simple single cell model. Realistic model involving combinations of different cells, molecules and partly nonlinear physiological processes is highly complex. To the best of our knowledge, the calculations using complex model have been not performed.
1) The lowest field strength that has caused the effect in EEG, according to the reviewed studies, is 2.45 V/m (SAR=0.003 W/kg), close to the radio and TV broadcasting RF EMF field strength about 0.1 V/m. The future large-scale human, animal and in vitro studies are required to clarify the level and to increase the reliability of the experimentally determined threshold of RF EMF effect.
With the rapid development of electronic information in the past 30 years, technical achievements based on electromagnetism have been widely used in various fields pertaining to human production and life. Consequently, electromagnetic radiation (EMR) has become a substantial new pollution source in modern civilization. The biological effects of EMR have attracted considerable attention worldwide. The possible interaction of EMR with human organs, especially the brain, is currently where the most attention is focused. Many studies have shown that the nervous system is an important target organ system sensitive to EMR. In recent years, an increasing number of studies have focused on the neurobiological effects of EMR, including the metabolism and transport of neurotransmitters. As messengers of synaptic transmission, neurotransmitters play critical roles in cognitive and emotional behavior. Here, the effects of EMR on the metabolism and receptors of neurotransmitters in the brain are summarized.
The effect of exposure to radiofrequency fields on cancer risk in the general and working population: A protocol for a systematic review of human observational studies
Susanna Lagorio, Maria Blettner, Dan Baaken, Maria Feychting, Ken Karipidis, Tom Loney, Nicola Orsini, Martin Röösli, Marilia Silva Paulo, Mark Elwood. The effect of exposure to radiofrequency fields on cancer risk in the general and working population: A protocol for a systematic review of human observational studies. Environ Int. 2021 Aug 22;157:106828. doi: 10.1016/j.envint.2021.106828.
• A systematic review of all subject-relevant epidemiological studies is now needed.
• A detailed protocol ensures the review's transparency, utility and credibility.
• Original study validity will be evaluated with a customized OHAT risk of bias tool.
• Internal coherence and external plausibility will inform conclusions.
Background: The World Health Organization (WHO) has an ongoing project to assess potential health effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in the general and working population. Here we present the protocol for a systematic review of the scientific literature on cancer hazards from exposure to RF-EMF in humans, commissioned by the WHO as part of that project.
Objective: To assess the quality and strength of the evidence provided by human observational studies for a causal association between exposure to RF-EMF and risk of neoplastic diseases.
Eligibility criteria: We will include cohort and case-control studies investigating neoplasia risks in relation to three types of exposure to RF-EMF: near-field, head-localized, exposure from wireless phone use (SR-A); far-field, whole body, environmental exposure from fixed-site transmitters (SR-B); near/far-field occupational exposures from use of handheld transceivers or RF-emitting equipment in the workplace (SR-C). While no restriction on tumour type will be applied, we will focus on selected neoplasms of the central nervous system (brain, meninges, pituitary gland, acoustic nerve) and salivary gland tumours (SR-A); brain tumours and leukaemias (SR-B, SR-C).
Information sources: Eligible studies will be identified through Medline, Embase, and EMF-Portal.
Risk-of-bias assessment: We will use a tailored version of the OHAT's tool to evaluate the study's internal validity.
Data synthesis: We will consider separately studies on different tumours, neoplasm-specific risks from different exposure sources, and a given exposure-outcome pair in adults and children. When a quantitative synthesis of findings can be envisaged, the main aims of the meta-analysis will be to assess the strength of association and the shape of the exposure-response relationship; to quantify the degree of heterogeneity across studies; and explore the sources of inconsistency (if any). When a meta-analysis is judged inappropriate, we will perform a narrative synthesis, complemented by a structured tabulation of results and appropriate visual displays.
Evidence assessment: Confidence in evidence will be assessed in line with the GRADE approach.
Funding: This project is supported by the World Health Organization. Co-financing was provided by the New Zealand Ministry of Health; the Istituto Superiore di Sanità in its capacity as a WHO Collaborating Centre for Radiation and Health; ARPANSA as a WHO Collaborating Centre for Radiation Protection.
Registration: PROSPERO CRD42021236798.
Effects of Radiofrequency Field exposure on male fertility & pregnancy & birth outcomes: Protocols for a systematic review of experimental studies in non-human mammals & in human sperm exposed in vitro
• Male infertility and adverse pregnancy outcomes are relevant human health problems.
• Radiofrequency electromagnetic fields are widespread in the human environment.
• A link between radiofrequency and adverse reproductive outcomes is controversial.
• This is the protocol of WHO-funded systematic review and meta-analysis on this issue.
Background Radiofrequency Electromagnetic Fields (RF-EMF) at environmental level have been reported to induce adverse effects on the male reproductive system and developing embryos. However, despite the number of experiments conducted since the 1970s, the diversity of testing approaches and exposure conditions, inconsistencies among results, and dosimetric flaws have not yet permitted a solid assessment of the relationship between RF-EMF exposure and such effects, warranting a more systematic and methodologically rigorous approach to the evaluation of available data.
Objectives This study aims at evaluating the effects of RF-EMF exposure on male fertility and pregnancy outcomes by a systematic review (SR) of experimental studies, conducted in compliance with international guidelines. The evidence will be organized into three streams: 1) Studies evaluating the impact of RF-EMF on the male reproductive system of experimental mammals; 2) studies evaluating the impact of RF-EMF on human sperm exposed in vitro; 3) studies evaluating the impact of RF-EMF on adverse pregnancy, birth outcomes and delayed effects in experimental mammals exposed in utero.
Study eligibility and criteria Eligible studies will include peer-reviewed articles reporting of original results about effects of controlled exposures to RF-EMF in the frequency range 100 kHz–300 GHz on the selected outcomes without any language or year-of-publication restrictions. Eligible studies will be retrieved by calibrated search strings applied to three electronic databases, PubMed, Scopus and EMF Portal and by manual search of the list of references of included papers and published reviews.
Study appraisal and synthesis method The internal validity of the studies will be evaluated using the Risk of Bias (RoB) Rating Tool developed by National Toxicology Program/Office of Health Assessment and Translation (NTP/OHAT) integrated with input from the SYRCLE RoB tool. Given sufficient commensurate data, meta-analyses will be performed, otherwise narrative syntheses will be produced. Finally, the certainty of the effects of RF-EMF exposure on male fertility and pregnancy and birth outcomes will be established following GRADE.
Funding The study is financially supported by the World Health Organization.
Registration OSF Registration DOI https://doi.org/10.17605/OSF.
• No up to date comprehensive systematic review is available.
• Priority outcomes for head exposure are tinnitus, migraine, and headaches.
• Further priority outcomes are sleep disturbances and composite symptom scores.
Background Applications emitting radiofrequency electromagnetic fields (RF-EMF; 100 kHz to 300 GHz) are widely used for communication (e.g. mobile phones), in medicine (diathermy) and in industry (RF heaters). Concern has been raised that RF-EMF exposure affects health related quality of life, because a part of the population reports to experience a variety of symptoms related to low exposure levels below regulatory limits.
Objectives To systematically review the effects of longer-term or repeated local and whole human body RF-EMF exposure on the occurrence of symptoms evaluating migraine, tinnitus, headaches, sleep disturbances and composite symptom scores as primary outcomes.
Methods We will follow the WHO handbook for guideline development. For the development of the systematic review protocol we considered handbook for conducting systematic reviews for health effects evaluations from the National Toxicology Program-Office of Health Assessment and Translation (NTP-OHAT) and COSTER (Recommendations for the conduct of systematic reviews in toxicology and environmental health research).
Eligibility criteria Peer-reviewed epidemiological studies in the general population or workers aiming to investigate the association between local or whole-body RF-EMF exposure for at least one week and symptoms are eligible for inclusion. Only cohort, case-control and panel studies will be included.
Information sources We will search the scientific literature databases Medline, Web of Science, PsycInfo, Cochrane Library, Epistemonikos and Embase, using a predefined search strategy. This search will be supplemented by a search in the EMF-Portal and checks of reference lists of relevant papers and reviews.
Study appraisal and synthesis method Data from included papers will be extracted according to predefined forms. Findings will be summarized in tables, graphical displays and in a narrative synthesis of the available evidence, complemented with meta-analyses. We will separately review effects of local, far field and occupational exposure.
Risk of bias The internal validity of included studies will be assessed using the NTP-OHAT Risk of Bias Rating Tool for Human and Animal Studies, elaborated to observational RF-EMF studies.
Evidence appraisal To rate certainty of the evidence, we will use the OHAT GRADE-based approach for epidemiological studies.
Framework and funding This protocol concerns one of the ten different systematic reviews considered in a larger systematic review of the World Health Organization to assess potential health effects of exposure to RF-EMF in the general and working population.
Registration PROSPERO CRD42021239432.
Open access paper: https://www.sciencedirect.com/science/article/pii/S0160412021004773?via%3Dihub
More Reliable Bioeffects Studies at “High Band” 5G Frequencies
Kenneth R Foster, Vijayalaxmi. More Reliable Bioeffects Studies at “High Band” 5G Frequencies. Frontiers in Communications and Networks. 2:39. 2021. doi:10.3389/frcmn.2021.721925.
One major source of controversy related to possible health effects of radiofrequency radiation (RFR) is the large number of reported statistically significant effects of exposure, over the entire RF part of the spectrum and over a wide range of exposure levels, even as health agencies do not find clear evidence for health hazards of exposure at levels within current IEEE and ICNIRP exposure limits. This Perspective considers 31 studies related to genetic damage produced by exposure to RFR at frequencies above 6 GHz, including at millimeter-wave (mm-wave) frequencies. Collectively, the papers report many statistically significant effects related to genetic damage, many at exposure levels below current exposure limits. However, application of five risk of bias (RoB) criteria and other considerations suggest that the studies in many cases are vulnerable to false discovery (nonreplicable results). The authors call for improvements in study design, analysis and reporting in future bioeffects research to provide more reliable information for health agencies and regulatory decision makers. This Perspective is a companion to another Perspective by Mattsson et al. elsewhere in this volume (Mattsson et al., 2021).
Conflict of interest
KF has received minor support for research on an unrelated topic (thermal dosimetry) by Microwave and Wireless Forum, an industry group.
The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Jerdvisanop Chakarothai, Wake Kanako, Fujii Katsumi. Dosimetry of Various Human Bodies Exposed to Microwave Broadband Electromagnetic Pulses. Frontiers in Public Health. 9:1182. 2021. doi:10.3389/fpubh.2021.725310.
In this paper, human exposures to ultra-wideband (UWB) electromagnetic (EM) pulses in the microwave region are assessed using a frequency-dependent FDTD scheme previously proposed by the authors. Complex permittivity functions of all biological tissues used in the numerical analyses are accurately expressed by the four-term Cole–Cole model. In our method, we apply the fast inverse Laplace transform to determine the time-domain impulse response, utilize the Prony method to find the Z-domain representation, and extract residues and poles for use in the FDTD formulation. Update equations for the electric field are then derived via the Z-transformation. Firstly, we perform reflection and transmission analyses of a multilayer composed of six different biological tissues and then confirm the validity of the proposed method by comparison with analytical results. Finally, numerical dosimetry of various human bodies exposed to EM pulses from the front in the microwave frequency range is performed, and the specific energy absorption is evaluated and compared with that prescribed in international guidelines.
We have performed numerical dosimetry on human bodies illuminated by an EM pulse from the front by using the (FD)2TD method, previously proposed by the authors. The method fully considers broadband characteristics of the complex relative permittivity of the biological media used in the analysis model via the application of the FILT and the Prony method. Firstly, we demonstrated the validity of the update coefficients, i.e., the residues and poles of the expression for the IIR in the z-domain, by comparing the numerical reflection coefficients with those derived from the EM theory. It was clarified that the numerical results within 2% of those obtained theoretically over a broad frequency range from 50 MHz to 10 GHz, demonstrating the validity of the proposed approach. It was also found that the transmission characteristics of the EM pulse into the CSF layer of a multilayer mimicking a human head are almost flat over a frequency range between 300 and 800 MHz and that the transmission decreases with increasing EM traveling distance from the skin boundary due to higher energy absorption at superficial biological tissues such as “Skin” and “Fat” when the frequency is higher than 1 GHz. Therefore, most of the pulse energy that penetrates into the biological body has a frequency below 1 GHz. Then, numerical dosimetry of various human models exposed to an EM pulse having a frequency component of up to ~1.3 GHz was performed. The whole-body average SAR at 24 frequencies was determined by a single run of broadband FDTD simulations. The results matched those published in the literature, demonstrating the validity and availability of the proposed FDTD method. Then the SA distribution of each numerical model was determined, and it was found that the maximum SA occurs at the hands and neck for the ungrounded model, while they appear at the hands and ankle when the model is grounded. The maximum SA value was 0.290 pJ/kg for an incident electric field strength of 1 V/m or 0.437 nJ/kg for an incident power density of 2 W/m2. It has been shown for the first time that, by using our proposed FDTD approach with the FILT and the Prony method, we can obtain quantitatively detailed information on SA that can be compared with the limits prescribed in international guidelines or standards.
Simultaneous exposure to electromagnetic field from mobile phone and unimpeded fructose drinking during pre-, peri-, and post-pubertal stages perturbs the hypothalamic and hepatic regulation of energy homeostasis by early adulthood: experimental evidence
Ruchi Tripathi, Sanjay Kumar Banerjee, Jay Prakash Nirala, Rajani Mathur. Simultaneous exposure to electromagnetic field from mobile phone and unimpeded fructose drinking during pre-, peri-, and post-pubertal stages perturbs the hypothalamic and hepatic regulation of energy homeostasis by early adulthood: experimental evidence. Environ Sci Pollut Res Int. 2021 Sep 2. doi: 10.1007/s11356-021-15841-y.
The present-day children-adolescents ubiquitously use the mobile phones and unrestrictedly consume fructose-laden diet. Unfortunately, a rise in the incidence of insulin resistance and fatty liver syndrome in young adults has also been recorded. To delineate a possible correlate, the effect of exposure to electromagnetic field (EMF) from the mobile phone and unrestricted fructose intake during pre-, peri-, and post-pubertal stages of development on orexigenic and anorexigenic signals arising from the hypothalamus and liver of rats is investigated here. The study design included four arms, i.e., "Normal", "Exposure Only (ExpO)", "Fructose Only (FruO)", and "Exposure with Fructose (EF)", wherein weaned rats received either "normal chow and drinking water" or "normal chow and fructose (15%) drinking solution" in presence and absence of EMF exposure (2 h/day) for 8 weeks. The results indicate that the total calories consumed by the EF were higher by early adulthood than normal, possibly under the influence of the raised levels of the orexigenic hormone, i.e., ghrelin, and it reflected as raised rate of weight gain. At early adulthood, the EF recorded mitigated response and sensitivity of insulin. Despite EF being a "fed-state", both centrally and peripherally, the glycolysis was restrained, but the gluconeogenesis was raised. Additionally, the altered lipid profile and the glycogen levels indicate that the EF developed fatty liver. The energy homeostasis of the EF was compromised as evidenced by (a) reduced expression of the glucosensors-GLUT2 and glucokinase in the hypothalamus and liver and (b) reduced expression of the cellular energy regulator-AMPK, orexigenic peptide-NPY, and anorexigenic peptide-POMC in the hypothalamus. Taken together, the present study evidences that the exposure to EMFfrom the mobile phone and unrestricted fructose intake during childhood-adolescence impairs the central and peripheral pathways that mediate the glucosensing, glucoregulation, feeding, and satiety behavior by early adulthood.
Anjali Sharma, Sadhana Shrivastava, Sangeeta Shukla. Oxidative damage in the liver and brain of the rats exposed to frequency-dependent radiofrequency electromagnetic exposure: Biochemical and histopathological evidence. Free Radic Res. 2021 Aug 17;1-30. doi: 10.1080/10715762.2021.1966001.
• EMR exposure showed frequency-dependent toxicity.
• Alterations in blood profile and modifications in the serological markers.
• Increasing lipid peroxidation indicating membrane damage.
• Inhibition of acetylcholinesterase activity affecting cholinergic neurotransmission.
• EMR exposure resulted in the loss of cellular energy and production of excess amounts of ROS thereby altering several antioxidant enzymes.
• Histopathological evidence of severe degenerative changes in the liver and brain.
The study aimed to discover a link between the liver and brain's functional status due to frequency dependent-radiofrequency electromagnetic radiation (RF-EMR).
Our findings documented that the frequency of EMR exposure is a significant factor associated with its toxicity, the extent of toxicity is increased with a simultaneous increase in the frequency of exposure. In addition, this study confirms that EMR exposure initiates hepatic and neural injury, but the potency of damage was more prominent in the brain.Our results will provide support for future studies in the analysis of electromagnetic radiation and its associated systemic injury.
Xie Wen, Xu Rui, Fan Caiyun, Yang Chunyu, Chen Haiyan, Cao Yi. 900 MHz Radiofrequency Field Induces Mitochondrial Unfolded Protein Response in Mouse Bone Marrow Stem Cells. Frontiers in Public Health. 9:1265. 2021. doi: 10.3389/fpubh.2021.724239
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 (UPR<sup>mt</sup>).Methods: BMSCs were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 120 μW/cm<sup>2</sup> 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 UPR<sup>mt</sup>, 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 UPR<sup>mt</sup>-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/cm<sup>2</sup> power flux density could increase ROS level and activate a transient UPR<sup>mt</sup> 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 UPR<sup>mt</sup> remains to be further studied.
Open access paper: https://www.frontiersin.org/
Saurabh Verma, Gaurav K Keshri, Santanu Karmakar, Kumar Vyonkesh Mani, Satish Chauhan, Anju Yadav, Manish Sharma, Asheesh Gupta. Effects of Microwave 10 GHz Radiation Exposure in the Skin of Rats: An Insight on Molecular Responses.
Radiat Res. 2021 Aug 18. doi: 10.1667/RADE-20-00155.1.
Microwave (MW) radiation poses the risk of potential hazards on human health. The present study investigated the effects of MW 10 GHz exposure for 3 h/day for 30 days at power densities of 5.23 ± 0.25 and 10.01 ± 0.15 mW/cm2 in the skin of rats. The animals exposed to 10 mW/cm2 (corresponded to twice the ICNIRP-2020 occupational reference level of MW exposure for humans) exhibited significant biophysical, biochemical, molecular and histological alterations compared to sham-irradiated animals. Infrared thermography revealed an increase in average skin surface temperature by 1.8°C and standard deviation of 0.3°C after 30 days of 10 mW/cm2 MW exposure compared to the sham-irradiated animals. MW exposure also led to oxidative stress (ROS, 4-HNE, LPO, AOPP), inflammatory responses (NFkB, iNOS/NOS2, COX-2) and metabolic alterations [hexokinase (HK), lactate dehydrogenase (LDH), citrate synthase (CS) and glucose-6-phospahte dehydrogenase (G6PD)] in 10 mW/cm2 irradiated rat skin. A significant alteration in expression of markers associated with cell survival (Akt/PKB) and HSP27/p38MAPK-related stress-response signaling cascade was observed in 10 mW/cm2 irradiated rat skin compared to sham-irradiated rat skin. However, MW-irradiated groups did not show apoptosis, evident by unchanged caspase-3 levels. Histopathological analysis revealed a mild cytoarchitectural alteration in epidermal layer and slight aggregation of leukocytes in 10 mW/cm2 irradiated rat skin. Altogether, the present findings demonstrated that 10 GHz exposure in continuous-wave mode at 10 mW/cm2 (3 h/day, 30 days) led to significant alterations in molecular markers associated with adaptive stress-response in rat skin. Furthermore, systematic scientific studies on more prevalent pulsed-mode of MW-radiation exposure for prolonged duration are warranted.
High power radiofrequencies may transiently or permanently disrupt the functioning of electronic devices, but their effect on living systems remains unknown. With the aim to evaluate the safety and biological effects of narrow-band and wide-band high-power electromagnetic (HPEM) waves, we studied their effects upon exposure of healthy and tumor-bearing mice. In field experiments, the exposure to 1.5 GHz narrow-band electromagnetic fields with the incident amplitude peak value level in the range of 40 kV/m and 150 MHz wide-band electric fields with the amplitude peak value in the range of 200 kV/m, did not alter healthy and tumor-bearing animals' growth, nor it had any impact on cutaneous murine tumors' growth. While we did not observe any noticeable behavioral changes in mice during the exposure to narrow-band signals when wide-band HPEM signals were applied, mice could behave in a similar way as they respond to loud noise signals: namely, if a mouse was exploring the cage prior to signal application, it returned to companion mates when wide-band HPEM signals were applied. Moreover, the effect of wide-band signals was assessed on normal blood vessels permeability in real-time in dorsal-chamber-bearing mice exposed in a pilot study using wide-band signal applicators. Our pilot study conducted within the applicator and performed at the laboratory scale suggests that the exposure to wide-band signals with the amplitude of 47.5 kV/m does not result in increased vessel permeability.
Pooled analysis of recent studies of magnetic fields and childhood leukemia
- • No association in recent studies between magnetic fields and childhood leukemia.
- • Current results are not in line with previous pooled analyses.
- • A small elevated risk for the aggregate evidence remains.
Background Over forty epidemiologic studies have addressed an association between measured or calculated extremely-low-frequency magnetic fields (MF) and childhood leukemia. These studies have been aggregated in a series of pooled analyses, but it has been 10 years since the last such.
Methods We present a pooled analysis combining individual-level data (24,994 cases, 30,769 controls) from four recent studies on MF and childhood leukemia.
Human detection thresholds of DC, AC, and hybrid electric fields: a double-blind study
Michael Kursawe, Dominik Stunder, Thomas Krampert, Andrea Kaifie, Sarah Drießen, Thomas Kraus, Kathrin Jankowiak. Human detection thresholds of DC, AC, and hybrid electric fields: a double-blind study. Environ Health. 2021 Aug 21;20(1):92. doi: 10.1186/s12940-021-00781-4.
Background: In the course of the ongoing transition of electric energy systems, transmission corridors are often upgraded to higher voltages and other technologies leading to another quality of human exposure. The study aims to determine human detection thresholds for direct current (DC), alternating current (AC), and hybrid electric fields (various DC; constant AC).
Methods: A total of 203 participants were exposed to DC, AC, and hybrid electric fields (EFs) in a highly specialized whole-body exposure laboratory using a double-blind experimental setting. Additionally, the participants were exposed to ion currents in part of the DC and hybrid sessions. To investigate environmental influences, relative humidity was changed in two subgroups during EF perception. Methods derived from the signal detection theory and the adaptive staircase procedure based on the single interval adjustment matrix were used to assess individual sensitivity and detection thresholds, respectively.
Results: The results indicated that detection thresholds of hybrid EF were lower compared to single EF presentation of DC or AC. Ion current exposure enhanced EF perception. High relative humidity facilitated DC EF perception, whereas low relative humidity reinforced the perception of AC EFs.
Conclusions: With this systematic investigation of human perception of DC, AC, and hybrid EFs, detection thresholds were provided, which can help improve the construction processes of energy transmission systems and the prevention of unwanted sensory perception by contributing to the determination of limit values.
We enhanced the external validity of the results by investigating subgroups across different levels of relative humidity. Hints for an enhanced perception of DC EF in a high-humidity environment and a facilitated AC perception under low-humidity conditions were confirmed. These results may further contribute to the understanding of the underlying mechanisms and should be considered as well in the discussion on recommendations for EF exposure. Thus, this study provided reliable EF detection thresholds that add quantitative information on sensory perception to the discourse on the impact of EF exposure. In this manner, it can help to improve the construction processes of planned HVDC and hybrid overhead power lines.
Effects of Wi-Fi Radiofrequency Radiation on Carbapenem-Resistant Klebsiella pneumoniae
Ilham Said-Salman, Wissam Yassine, Ali Rammal, Mohammad Hneino, Hoda Yusef, Mohamed Moustafa. Effects of Wi-Fi Radiofrequency Radiation on Carbapenem-Resistant Klebsiella pneumoniae. Bioelectromagnetics. 2021 Aug 1. doi: 10.1002/bem.22364.
The hazardous consequences of electromagnetic field (EMF) exposure represent a public health concern. Common sources of EMF include smartphones and wireless fidelity (Wi-Fi). The aim of our study is to assess whether exposure to Wi-Fi radiofrequency radiation influences the pathogenic traits of carbapenem-resistant Klebsiella pneumoniae. The susceptibility to antibiotics was evaluated by the determination of minimum inhibitory concentrations (MIC). In this study, K. pneumoniae showed a non-linear response to treatments with Colistin and Gentamycin following different Wi-Fi exposure periods. Transmission electron microscopy revealed morphological changes in the bacterial cell membrane within 24 h of Wi-Fi exposure. Crystal violet quantification and quantitative real-time polymerase chain reaction showed that the ability to form biofilms was greater in Wi-Fi exposed K. pnemoniae when compared to control. Moreover, higher levels of bcsA, mrkA, and luxS messenger RNAs were observed. Our data suggest that Wi-Fi exposure can influence bacteria in a stressful way, leading to an alteration in their antibiotic susceptibility, morphological changes, and cumulative biofilm formation.
Although the evidence is inconclusive, epidemiological studies strongly suggest that increased exposure to electromagnetic radiation (EMR) increases the risk of brain tumors, parotid gland tumors, and seminoma. The International Agency for Research on Cancer (IARC) has classified mobile phone radiofrequency radiation as possibly carcinogenic to humans (Group 2B). Humans being are inadvertently being exposed to EMR as its prevalence increases, mainly through mobile phones. Radiation exposure is unavoidable in the current context, with mobile phones being an inevitable necessity. Prudent usage of medicinal plants with a long history of mention in traditional and folklore medicine and, more importantly, are safe, inexpensive, and easily acceptable for long-term human use would be an appealing and viable option for mitigating the deleterious effects of EMR. Plants with free radical scavenging, anti-oxidant and immunomodulatory properties are beneficial in maintaining salubrious health. Green tea polyphenols, Ginkgo biloba, lotus seedpod procyanidins, garlic extract, Loranthus longiflorus, Curcuma amada, and Rosmarinus officinalis have all been shown to confer neuroprotective effects in validated experimental models of study. The purpose of this review is to compile for the first time the protective effects of these plants against mobile phone-induced neuronal damage, as well as to highlight the various mechanisms of action that are elicited to invoke the beneficial effects.
Recent research suggests green tea polyphenols, Ginkgo biloba, lotus seedpod procyanidins, garlic extract, Loranthus longiflorus, Curcuma amada, and Rosmarinus officinalis may be beneficial in preventing EMR-induced brain damage.The brain-protective effects of these plants are thought to be mediated by a variety of mechanisms, including scavenging of radiation-induced free radicals, increased cellular anti-oxidant status, inhibition of neuronal apoptosis, and improved neurobehavioral outcomes. Given the increasing prevalence of intentional and unintentional EMR exposure in daily life, more comprehensive cell culture, animal, and clinical studies using pharmacologically validated models that incorporate multiple biochemical, physiological, pathological, and neurobehavioral end points are required.Such studies will be highly beneficial because these agents have been validated for various health benefits and are known to improve/maintain general health; if they are also protective against EMR-induced damage in multiple studies, they will be extremely useful to both the scientific fraternity and society at large.The most important factors to consider when starting clinical studies are that these medicinal plants have been used since antiquity, are non-toxic, have a wide range of medicinal properties, and are easily acceptable for human use. Green tea polyphenols could be particularly useful because it is one of the most widely consumed beverages, has a wide range of medicinal applications, and is a relatively non-toxic agent with widespread acceptance. According to data from various clinical trial registries, green tea is being studied at various stages (phases 1 to 4) in humans for various ailments. A well-designed study aimed at collecting secondary endpoints with a checklist for daily mobile phone use in volunteers enrolled in clinical trials will be a cost- and time-effective way to validate the neuroprotective effects of medicinal plants against EMR-induced damage.
In this paper, the chronotoxicity of radiofrequency fields (RF) in
the pubertal testis development and the involved molecular pathways
were investigated by exposing four-week-old mice to RF (1800 MHz, SAR,
0.50 W/kg) in the morning and evening of each day for three weeks. Then,
pathological changes and functional indices within the testis were
determined. We also used a long non-coding RNA (lncRNA) microarray and
GO/KEGG pathway analyses to determine lncRNA expression profiles and
predict their potential functions. The cis and trans regulation of
lncRNAs were investigated, and an interaction network was constructed
using Cytoscape software. RF exposure led to a range of pathological
changes in the testes of adolescent mice, as testicular weights and
daily sperm productions decreased, and the testosterone secretion
reduced. Furthermore, RF induced dysregulation in the expression of
testicular lncRNAs. We identified 615 and 183 differentially expressed
lncRNAs that were associated with morning and evening exposure to RF,
respectively. From 15 differential expression lncRNAs both in morning RF
group and evening RF group, we selected 6 lncRNAs to be validated by
quantitative reverse transcription PCR (qRT-PCR). The differentially
expressed lncRNAs induced by morning RF exposure were highly correlated
with many different pathways, including Fanconi syndrome, metabolic
processes, cell cycle, DNA damage, and DNA replication. Trans-regulation
analyses further showed that differentially expressed lncRNAs were
involved in multiple transcription factor-regulated pathways, such as
TCFAP4, NFkB, HINFP, TFDP2, FoxN1, and PAX5. These transcription factors
have all been shown to be involved in the modulation of testis
development, cell cycle progression, and spermatogenesis. These findings
suggest that the extent to which 1800 MHz RF induced toxicity in the
testes and changed the expression of lncRNAs showed differences between
morning exposure and evening exposure. These data indicate that
differentially expressed lncRNAs play crucial roles in the RF exposure
damage to the developing pubertal testis. Collectively, our findings
provide a better understanding of the mechanisms underlying the toxic
effects of RF exposure on testicular development.
Setsuko Komatsu, Junya Maruyama, Takashi Furuya, Xiaojian Yin, Hisateru Yamaguchi, Keisuke Hitachi, Natsuki Miyashita, Kunihiro Tsuchida, Masahiko Tani. Proteomic and Biological Analyses Reveal the Effect on Growth under Flooding Stress of Chickpea Irradiated with Millimeter Waves. J Proteome Res. 2021 Aug 30. doi: 10.1021/acs.jproteome.1c00368.
Chickpea cultivated on marginal lands in arid and semiarid tropics is one of the food legumes, and its growth is reduced by flooding stress. Millimeter-wave irradiation has influences on organisms, and it improves the growth of plants such as soybean. To reveal the dynamic effects of millimeter-wave irradiation on chickpea under flooding, gel- and label-free proteomic analysis was conducted. Millimeter-wave irradiation improved chickpea growth and its tolerance to flooding stress. According to functional categorization, oppositely changed proteins were correlated with photosynthesis, fermentation, and protein degradation. Immunoblot analysis confirmed that RuBisCO activase and large subunits decreased in leaves under flooding; however, they are recovered in irradiated chickpea even if it was in this condition. The activity and accumulation of alcohol dehydrogenase increased in roots under flooding; however, this followed the same pattern. Cell death was significantly increased and decreased by flooding on unirradiated and irradiated chickpeas, respectively. These findings suggest that irradiation with millimeter waves on chickpea seeds improves the recovery of plant growth through regulation of photosynthesis in leaves and fermentation in roots. Furthermore, millimeter-wave irradiation might promote chickpea tolerance under flooding via the regulation of cell death.
Exposure to 60 Hz magnetic field can affect membrane proteins and membrane potential in human cancer cells
Seiya Hayashi, Makiko Kakikawa. Exposure to 60 Hz magnetic field can affect membrane proteins and membrane potential in human cancer cells. Electromagn Biol Med. 2021 Aug 15;1-8. doi: 10.1080/15368378.2021.1958340.
The experimental data support the hypothesis that extremely low frequency magnetic field (ELF-MF) can affect cell membranes. Since our previous studies suggested that MF changes the permeability of cell membrane, in this study we focused on the cell membrane and investigated the effect of 60 Hz, 50 mT MF on the membrane potential and membrane proteins. The membrane potentials of three cultured human cancer cell lines, A549, MES-SA, and MES-SA/Dx5, were increased by exposure to ELF-MF. When exposed to MF and an anticancer drug, changes in the membrane potentials were detected in A549 and MES-SA cells, but not in the multi drug-resistant cells, MES-SA/Dx5. We examined whether MF has an influence on the membrane proteins extracted from cultured A549 cells, using DiBAC4(3) dye enhanced fluorescence binding to a hydrophobic site. The increase in fluorescence observed following MF exposure for 10 min indicated that the structure of the hydrophobic site on the membrane proteins changed and became more likely to bind the probe dye. A decrease in fluorescence was detected following exposure to MF for 240 min. These results indicated that 60 Hz, 50 mT MF causes changes in the membrane potential of cultured cancer cells and the conformation of membrane proteins extracted from cultured cancer cells, and has different effects depending on the exposure time.
Purpose: The mechanisms underlying anticancer effects of electromagnetic fields are poorly understood. An alternating electric field-generating therapeutic device called Optune™ device has been approved for the treatment of glioblastoma (GBM). We have developed a new device that generates oscillating magnetic fields (OMF) by rapid rotation of strong permanent magnets in specially designed patterns of frequency and timing and have used it to treat an end-stage recurrent GBM patient under an expanded access/compassionate use treatment protocol. Here, we ask whether OMF causes selective cytotoxic effects in GBM and whether it is through generation of reactive oxygen species (ROS).
Methods: We stimulated patient derived GBM cells, lung cancer cells, normal human cortical neurons, astrocytes, and bronchial epithelial cells using OMF generators (oncoscillators) of our Oncomagnetic Device and compared the results to those obtained under unstimulated or sham-stimulated control conditions. Quantitative fluorescence microscopy was used to assess cell morphology, viability, and ROS production mechanisms.
Results: We find that OMF induces highly selective cell death of patient derived GBM cells associated with activation of caspase 3, while leaving normal tissue cells undamaged. The cytotoxic effect of OMF is also seen in pulmonary cancer cells. The underlying mechanism is a marked increase in ROS in the mitochondria, possibly in part through perturbation of the electron flow in the respiratory chain.
Conclusion: Rotating magnetic fields produced by a new noninvasive device selectively kill cultured human glioblastoma and non-small cell lung cancer cells by raising intracellular reactive oxygen species, but not normal human tissue cells.
Combined effect of co-exposure to di (2-ethylhexyl) phthalates and 50-Hz magnetic-fields on promoting human amniotic cells proliferation
Liangjing Chen, Anfang Ye, Xiaochen Liu, Jingchun Lu, Qixin Xie, Yixin Guo, Wenjun Sun. Combined effect of co-exposure to di (2-ethylhexyl) phthalates and 50-Hz magnetic-fields on promoting human amniotic cells proliferation. Ecotoxicol Environ Saf. 2021 Aug 26;224:112704. doi: 10.1016/j.ecoenv.2021.112704.
Di (2-ethylhexyl) phthalate (DEHP) and extremely low-frequency electromagnetic fields (ELF-EMFs) exist far and wide in our surroundings. Studies have reported that both of DEHP and ELF-EMFs could promote cell proliferation which is related with adverse bioeffects. In this study, we investigated whether there is the combined effect between DEHP and 50-Hz magnetic fields (MFs) on cell proliferation in human amniotic (FL) cells. Results revealed that the low-concentration DEHP (1 μM) could promote FL cell proliferation, whereas the high-dose DEHP (100 μM) inhibited cell proliferation. When FL cells were treated jointly by a 50-Hz, 0.2-mT MF and 0.1 μM DEHP, the proliferation rate of cells was significantly higher than that of single factor exposure. Additionally, co-exposure to under-threshold MF and DEHP could cooperatively activate protein kinase B (Akt), sphingosine kinase 1 (SphK1) and extracellular signal regulated kinase (ERK) in a cascade manner, and finally mediate cell proliferation. Taken together, the findings of this study indicated that the co-exposure to under-threshold MF and DEHP could jointly promote cell proliferation through activating proliferation-related signal pathway, which warned us that it should be cautious about assessing the underlying health hazards of co-exposure to MFs and DEHP at under-threshold levels.
Evaluation of Pulsed Electromagnetic Field Effects: A Systematic Review and Meta-Analysis on Highlights of Two Decades of Research In Vitro Studies
Mahsa Mansourian, Ahmad Shanei. Evaluation of Pulsed Electromagnetic Field Effects: A Systematic Review and Meta-Analysis on Highlights of Two Decades of Research In Vitro Studies. Biomed Res Int. 2021 Jul 29;2021:6647497. doi: 10.1155/2021/6647497.
Pulsed electromagnetic field (PEMF) therapy is a type of physical stimulation that affects biological systems by producing interfering or coherent fields. Given that cell types are significantly distinct, which represents an important factor in stimulation, and that PEMFs can have different effects in terms of frequency and intensity, time of exposure, and waveform. This study is aimed at investigating if distinct positive and negative responses would correspond to specific characteristics of cells, frequency and flux density, time of exposure, and waveform. Necessary data were abstracted from the experimental observations of cell-based in vitro models. The observations were obtained from 92 publications between the years 1999 and 2019, which are available on PubMed and Web of Science databases. From each of the included studies, type of cells, pulse frequency of exposure, exposure flux density, and assayed cell responses were extracted. According to the obtained data, most of the experiments were carried out on human cells, and out of 2421 human cell experiments, cell changes were observed only in 51.05% of the data. In addition, the results pointed out the potential effects of PEMFs on some human cell types such as MG-63 human osteosarcoma cells (p value < 0.001) and bone marrow mesenchymal stem cells. However, human osteogenic sarcoma SaOS-2 (p < 0.001) and human adipose-derived mesenchymal stem cells (AD-MSCs) showed less sensitivity to PEMFs. Nevertheless, the evidence suggests that frequencies higher than 100 Hz, flux densities between 1 and 10 mT, and chronic exposure more than 10 days would be more effective in establishing a cellular response. This study successfully reported useful information about the role of cell type and signal characteristic parameters, which were of high importance for targeted therapies using PEMFs. Our findings would provide a deeper understanding about the effect of PEMFs in vitro, which could be useful as a reference for many in vivo experiments or preclinical trials.
Alejandro González-Vidal, Silvia Mercado-Sáenz, Antonio M Burgos-Molina, Francisco Sendra-Portero, Miguel J Ruiz-Gómez. Growth alteration of Allium cepa L. roots exposed to 1.5 mT, 25 Hz pulsed magnetic field. Int J Environ Health Res. 2021 Sep 2;1-13. doi: 10.1080/09603123.2021.1972090.
The response of plants to magnetic fields (MF) is not fully understood. This work studies the effects of pulsed MF on the germination and growth of Allium cepa roots. Onions were exposed to 25Hz, 1.5mT, 33h. Pulsed MF was generated by a Helmholtz-type equipment that generated rectangular voltage pulses. The results showed that fewer roots grew in the specimens exposed to pulsed MF (14±6 roots on day 1 to 21±8 on day 4) than in the control groups (32±17 to 48±23) (p<0.05 Friedman). Control specimens showed a root mean length of 7±4 mm (day 1) and 24±10 mm (day 4). The specimens treated with pulsed MF showed a length of 4±2 mm (day 1), reaching 18±9 mm on day 4 (p<0.001 ANOVA). In conclusion, the exposure of Allium cepa specimens to 25Hz, 1.5mT pulsed MF during 33h produces a decrease in the germination and growth of roots.
Electrical Control of Escherichia coli Growth Measured with Simultaneous Modulation and Imaging
Xu Han, Bradley R Foster, Christine K Payne. Electrical Control of Escherichia coli Growth Measured with Simultaneous Modulation and Imaging. Bioelectricity. 2020 Sep 1;2(3):221-228. doi: 10.1089/bioe.2020.0002.
Background: The use of electricity to mediate bacterial growth is unique in providing spatial control, but requires a more detailed understanding. Methods: We use two gold wires on a glass coverslip with an overlayer of agar to image Escherichia coli cells with brightfield and fluorescence microscopy while simultaneously applying a voltage. Cells outside of the wires provide a control population to measure cell growth as a function of voltage, rather than any difference in culture conditions or growth phase. Results: An applied voltage suppresses the fraction of E. coli undergoing elongation and division with recovery to control values when the voltage is removed. Depolarization is observed over the same voltage range suggesting a membrane potential-mediated response. Conclusions: Our experiments identify and use subcytotoxic voltages to measure differences in the fraction of E. coli cells elongating and dividing as a function of applied voltage. It is hoped that this research will inform the developing field of bacterial electrophysiology.
Can static electric fields increase the activity of nitric oxide synthase and induce oxidative stress and damage of spleen?
Li Dong, Junli Xiang, Jingyi Guo, Guangdi Chen, Guoqing Di. Can static electric fields increase the activity of nitric oxide synthase and induce oxidative stress and damage of spleen? Environ Sci Pollut Res Int. 2021 Aug 16. doi: 10.1007/s11356-021-15853-8.
With the rapid development of ultra-high-voltage (UHV) direct-current (DC) transmissions, the impact of static electric fields (SEF) in the vicinity of overhead UHV DC transmission lines on health has aroused much public concern. This study explored the effects of 56.3kV/m SEF on the spleen of mice. Results showed that SEF exposure of 21days significantly increased malonic dialdehyde content, superoxide dismutase activity, calcineurin activity, nitric oxide synthase (NOS) activity, and the mRNA expression levels of tumor necrosis factor-α (TNF-α) and nuclear factor-κB (NF-κB) in the spleen and caused the separation of nucleus and nuclear membrane, the disappearance of mitochondrial membrane, and the deficiency of mitochondrial cristae in splenic lymphocytes. By analysis and discussion, it was deduced that SEF could induce oxidative stress of the spleen by increasing the activity of NOS. Oxidative stress could further cause ultrastructural changes of splenic lymphocytes. Moreover, oxidative stress could cause the increase of the mRNA expression levels of TNF-α and NF-κB, which contributed to the occurrence of spleen inflammation.
Effects of Extremely Low Frequency Electromagnetic Field on different developmental stages of Drosophila melanogaster
Neha Agrawal, Kalyani Verma, Doli Baghel, Amitabh Chauhan, Dipti N Prasad, Sanjeev K Sharma, Ekta Kohli. Effects of Extremely Low Frequency Electro Magnetic Field on different developmental stages of Drosophila melanogaster. Int J Radiat Biol. 2021 Aug 17;1-35. doi: 10.1080/09553002.2021.1969465.
Purpose: The model biological organism Drosophila melanogaster has been utilized to assess effect of extremely low-frequency electromagnetic field (ELF-EMF) on locomotion, longevity, developmental dynamics, cell viability and oxidative stress.
Materials and method: Developmental stages of Drosophila melanogaster (Oregon R strain) individually exposed to ELF-EMF (75 Hz, 550 µT) for 6 h once for acute exposure. For chronic exposure, complete life cycle of fly, that is, egg to adult fly was exposed to ELF-EMF for 6 h daily. The effect of exposure on their crawling and climbing ability, longevity, development dynamics, cellular damage and oxidative stress (generation of Reactive Oxygen Species (ROS)) was evaluated.
Results: The crawling ability of larvae was significantly (p< 0.05) reduced on acute (third stage instar larvae) as well as chronic exposure (F0 and F1 larvae). When locomotion of flies were tested using climbing assay, no alteration was observed in their climbing ability under both acute and chronic exposure, however, when their speed of climbing was compared, a significant decrease in speed of F1 flies was observed (p value 0.0027) on chronic exposure. The survivability of flies was significantly affected under chronic and acute exposure (at third stage instar larvae). In case of acute exposure of the third stage instar larvae, though all the flies were eclosed by the 17th day, but there was a significant decline in the number of flies (p value 0.007) in comparison to control. While, in case of chronic exposure apart from low number of flies eclosed in comparison to control, there was delay in eclosion by one day (p value 0.0004). Using trypan blue assay the internal gut damage of third stage instar larvae was observed. Under acute exposure condition at third stage instar larvae, 30% larvae has taken up trypan blue, while only 10% larvae from acute exposure at adult stage. On chronic exposure, 50% larvae of the F1 generation have taken up trypan blue. On evaluation of oxidative stress, there is significant rise in ROS in case of acute exposure at third stage instar larvae (p value 0.0004), adult fly stage (p value 0.0004) and chronic exposure (p value 0.0001).
Conclusion: ELF-EMF has maximum effects on acute exposure of third stage instar larvae and chronic exposure (egg to adult fly stage). These results suggest that electromagnetic radiations, though have become indispensible part of our lives but they plausibly effect our health.
Electromagnetic Fields and Calcium Signaling by the Voltage Dependent Anion Channel
Volker Ullrich, Hans-Jürgen Apell. Electromagnetic Fields and Calcium Signaling by the Voltage Dependent Anion Channel. Open Journal of Veterinary Medicine. 11(1):57-86, January 2021. DOI: 10.4236/ojvm.2021.111004.
Electromagnetic fields (EMFs) can interact with biological tissues exerting positive as well as negative effects on cell viability, but the underlying sensing and signaling mechanisms are largely unknown. So far in excitable cells EMF exposure was postulated to cause Ca2+ influx through voltage-dependent Ca channels (VDCC) leading to cell activation and an antioxidant response. Upon further activation oxidative stress causing DNA damage or cell death may follow. Here we report collected evidence from literature that voltage dependent anion channels (VDAC) located not only in the outer microsomal membrane but also in the cytoplasmic membrane convert to Ca2+ conducting channels of varying capacities upon subtle changes of the applied EMF even in non-excitable cells like erythrocytes. Thus, VDAC can be targeted by external EMF in both types of membranes to release Ca2+ into the cytosol. The role of frequency, pulse modulation or polarization remains to be investigated in suitable cellular models. VDACs are associated with several other proteins, among which the 18 kDa translocator (TSPO) is of specific interest since it was characterized as the central benzodiazepine receptor in neurons. Exhibiting structural similarities with magnetoreceptors we propose that TSPO could sense the magnetic component of the EMF and thus together with VDAC could trigger physiological as well as pathological cellular responses. Pulsed EMFs in the frequency range of the brain-wave communication network may explain psychic disturbances of electromagnetic hypersensitive persons. An important support is provided from human psychology that states deficits like insomnia, anxiety or depression can be treated with diazepines that indicates apparent connections between the TSPO/VDAC complex and organismic responses to EMF.
Induced radiofrequency fields in patients undergoing MRI (Magnetic Resonance Imaging) exams: insights for risk assessment
Aiping Yao, Manuel Murbach, Tolga Goren, Earl Zastrow, Wolfgang Kainz, Niels Kuster. Induced radiofrequency fields in patients undergoing MR examinations: insights for risk assessment. Phys Med Biol. 2021 Aug 25. doi: 10.1088/1361-6560/ac212d.
Purpose: To characterize and quantify the induced radiofrequency (RF) E-fields and B1+rms fields in patients undergoing magnetic resonance (MR) examinations; to provide guidance on aspects of RF heating risks for patients with and without implants; and to discuss some strengths and limitations of safety assessments in current ISO, IEC, and ASTM standards to determine the RF heating risks for patients with and without implants.
Methods: Induced E-fields and B1+rms fields during 1.5T and 3T MR examinations were numerically estimated for high-resolution patient models of the Virtual Population exposed to ten two-port birdcage RF coils from head to feet imaging landmarks over the full polarization space, as well as in surrogate ASTM phantoms.
Results: Worst-case B1+rms exposure greater than 3.5µT (1.5T) and 2µT (3T) must be considered for all MR examinations at the Normal Operating Mode limit. Representative induced electric (E)-field and specific absorption rate (SAR) distributions under different clinical scenarios allow quick estimation of clinical factors of high and reduced exposure. B1 shimming can cause +6dB enhancements to E-fields along implant trajectories. The distribution and magnitude of induced E-fields in the ASTM phantom differ from clinical exposures and are not always conservative for typical implant locations.
Conclusions: Field distributions in patient models are condensed, visualized for quick estimation of risks, and compared to those induced in the ASTM phantom. Induced E-fields in patient models can significantly exceed those in the surrogate ASTM phantom in some cases. In the recent 19e2 revision of the ASTMF2182 standard, the major shortcomings of previous versions have been addressed by requiring that the relationship between ASTM test conditions and in vivo tangential E-fields be established, e.g. numerically. With this requirement, the principal methods defined in the ASTM standard for passive implants are reconciled with those of the ISO10974 standard for active implantable medical devices.
How the Geomagnetic Field Influences Life on Earth - An Integrated Approach to Geomagnetobiology
Weronika Erdmann, Hanna Kmita, Jakub Z Kosicki, Łukasz Kaczmarek. How the Geomagnetic Field Influences Life on Earth - An Integrated Approach to Geomagnetobiology. Orig Life Evol Biosph. 2021 Aug 7. doi: 10.1007/s11084-021-09612-5.
Earth is one of the inner planets of the Solar System, but - unlike the others - it has an oxidising atmosphere, relatively stable temperature, and a constant geomagnetic field (GMF). The GMF does not only protect life on Earth against the solar wind and cosmic rays, but it also shields the atmosphere itself, thus creating relatively stable environmental conditions. What is more, the GMF could have influenced the origins of life: organisms from archaea to plants and animals may have been using the GMF as a source of spatial information since the very beginning. Although the GMF is constant, it does undergo various changes, some of which, e.g. a reversal of the poles, weaken the field significantly or even lead to its short-term disappearance. This may result in considerable climatic changes and an increased frequency of mutations caused by the solar wind and cosmic radiation. This review analyses data on the influence of the GMF on different aspects of life and it also presents current knowledge in the area. In conclusion, the GMF has a positive impact on living organisms, whereas a diminishing or disappearing GMF negatively affects living organisms. The influence of the GMF may also be an important factor determining both survival of terrestrial organisms outside Earth and the emergence of life on other planets.