Immunotoxicity of radiofrequency radiation

Growing evidence recommends that radiofrequency radiations might be a new type of environmental pollutant. The consequences of RFR on the human immune system have gained considerable interest in recent years, not only to examine probable negative effects on health but also to understand if RFR can modulate the immune response positively. Although several studies have been published on the immune effects of RFR but no satisfactory agreement has been reached. Hence this review aims to evaluate the RFR modulating impacts on particular immune cells contributing to various innate or adaptive immune responses. In view of existing pieces of evidence, we have suggested an intracellular signaling cascade responsible for RFR action. The bio-effects of RFR on immune cell morphology, viability, proliferation, genome integrity, and immune functions such as ROS, cytokine secretion, phagocytosis, apoptosis, etc. are discussed. The majority of existing evidence point toward the possible shifts in the activity, number, and/or function of immunocompetent cells, but the outcome of several studies is still contradictory and needs further studies to reach a conclusion. Also, the direct association of experimental studies to human risks might not be helpful as exposure parameters vary in real life. On the basis of recent available literature, we suggest that special experiments should be designed to test each particular signal utilized in communication technologies to rule out the hypothesis that longer exposure to RFR emitting devices would affect the immunity by inducing genotoxic effects in human immune cells.

Extremely low-frequency magnetic fields significantly enhance the cytotoxicity of methotrexate and can reduce migration of cancer cell lines via transiently induced plasma membrane damage

Extra Low-frequency Magnetic Fields (ELF-MFs) significantly enhance cellular uptake of methotrexate by inducing transient plasma membrane pores/damage. This enhanced 'dose loading' of methotrexate via the electromagnetically induced membrane pores leads to similar outcomes as the normal control while using significantly smaller therapeutic doses in vitro when compared to non-ELF-MF treated control. Approximately 10% of the typical therapeutic dose yielded similar results when used with ELF-MF. ELF-MFs increase PC12, THP-1 and HeLa proliferation in vitro (120% of the control). Analysis of adherent cells demonstrate significantly less migration towards an induced scratch injury (20 μm in 24 h when compared to a control). Our results suggest an important role for the use of ELF-MFs in the treatment of tumours that opens some new and exciting possibilities including using smaller therapeutic doses of chemotherapeutic agents and disrupting tumour metastasis.

Threshold of radiofrequency electromagnetic field effect on human brain

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.

CONCLUSIONS

The analyses of the physical model of nonthermal mechanisms of RF EMF effect leads to conclusion that no principal threshold of the effect can be determined. According to the review of experimental data, the rate of detected RF EMF effects is 76.7% in resting EEG studies, 41.7% in sleep EEG and 38.5% in behavioral studies. The changes in EEG probably appear earlier than alterations in behavior become evident. The lowest level of RF EMF at which the effect in EEG was detected is 2.45 V/m (SAR = 0.003 W/kg). There is a preliminary indication that the dependence of the effect on the level of exposure follows rather field strength than SAR alterations. However, no sufficient data are available for clarifying linearity-nonlinearity of the dependence of effect on the level of RF EMF. The finding that only part of people are sensitive to RF EMF exposure can be related to immunity to radiation or hypersensitivity. The changes in EEG caused by RF EMF appeared similar in the majority of analyzed studies and similar to these in depression. The possible causal relationship between RF EMF effect and depression among young people is highly important problem.

Understanding physical mechanism of low-level microwave radiation effect

PURPOSE

This topic review aims to explain the mechanism of low-level microwave (MW) radiation effect based on published research results. The review presents the analysis of theoretical and experimental results comprising underlying physics and derived biological-physiological consequences supported by experimental data.

CONCLUSIONS

The rotation of dipolar molecules causes polarization of dielectric medium and restructuring of hydrogen bonds between these molecules. The weakened hydrogen bonds decrease viscosity and enhance diffusion at constant temperature. All steps of proposed model have no critical frequency restrictions at MW frequencies and have been confirmed by electromagnetic field (EMF) theory and/or published experimental results. The synchronous cumulative impact of coherent MW electric field makes possible the field-induced effect despite the field strengths are much weaker than intermolecular fields. The rotation of dipolar molecules results in restructuring hydrogen bonds between the molecules despite the energy of MW radiation is much less than the energy of bonding. The cumulative impact of coherent MW field in a medium has been convincingly confirmed by the measurable dielectric permittivity of the medium. The described mechanism of MW field-induced effect confirms that the nature of the effect differs from the thermal effect and that the exposure by MW radiation can create the specific consequences in biology and materials not characteristic for conventional heating.

Extremely high-frequency electromagnetic radiation enhances neutrophil response to particulate agonists

The growing use of extremely high-frequency electromagnetic radiation (EHF EMR) in information and communication technology and in biomedical applications has raised concerns regarding the potential biological impact of millimeter waves (MMWs). Here, we elucidated the effects of MMW radiation on neutrophil activation induced by opsonized zymosan or E. coli in whole blood ex vivo. After agonist addition to blood, two samples were prepared. A control sample was incubated at ambient conditions without any treatment, and a test sample was exposed to EHF EMR (32.9-39.6 GHz, 100 W/m² ). We used methods that allowed us to assess the functional status of neutrophils immediately after exposure: oxidant production levels were measured by luminol-dependent chemiluminescence, and morphofunctional changes to neutrophils were observed in blood smears. Results revealed that the response of neutrophils to both agonists was intensified if blood was exposed to MMW radiation for 15 min. Neutrophils were intact in both the control and irradiated samples if no agonist was added to blood before incubation. Similarly, exposing suspensions of isolated neutrophils in plasma to MMW radiation enhanced cell response to both zymosan and E. coli. Heating blood samples was shown to be the primary mechanism underlying enhanced EHF EMR-induced oxidant production by neutrophils in response to particulate agonists. Bioelectromagnetics. 39:144-155, 2018. © 2017 Wiley Periodicals, Inc.

A Gal-MµS Device to Evaluate Cell Migratory Response to Combined Galvano-Chemotactic Fields

Electric fields have been studied extensively in biomedical engineering (BME) for numerous regenerative therapies. Recent studies have begun to examine the biological effects of electric fields in combination with other environmental cues, such as tissue-engineered extracellular matrices (ECM), chemical gradient profiles, and time-dependent temperature gradients. In the nervous system, cell migration driven by electrical fields, or galvanotaxis, has been most recently studied in transcranial direct stimulation (TCDS), spinal cord repair and tumor treating fields (TTF). The cell migratory response to galvano-combinatory fields, such as magnetic fields, chemical gradients, or heat shock, has only recently been explored. In the visual system, restoration of vision via cellular replacement therapies has been limited by low numbers of motile cells post-transplantation. Here, the combinatory application of electrical fields with other stimuli to direct cells within transplantable biomaterials and/or host tissues has been understudied. In this work, we developed the Gal-MµS device, a novel microfluidics device capable of examining cell migratory behavior in response to single and combinatory stimuli of electrical and chemical fields. The formation of steady-state, chemical concentration gradients and electrical fields within the Gal-MµS were modeled computationally and verified experimentally within devices fabricated via soft lithography. Further, we utilized real-time imaging within the device to capture cell trajectories in response to electric fields and chemical gradients, individually, as well as in combinatory fields of both. Our data demonstrated that neural cells migrated longer distances and with higher velocities in response to combined galvanic and chemical stimuli than to either field individually, implicating cooperative behavior. These results reveal a biological response to galvano-chemotactic fields that is only partially understood, as well as point towards novel migration-targeted treatments to improve cell-based regenerative therapies.

Inaccurate official assessment of radiofrequency safety by the Advisory Group on Non-ionising Radiation

The Advisory Group on Non-ionising Radiation (AGNIR) 2012 report forms the basis of official advice on the safety of radiofrequency (RF) electromagnetic fields in the United Kingdom and has been relied upon by health protection agencies around the world. This review describes incorrect and misleading statements from within the report, omissions and conflict of interest, which make it unsuitable for health risk assessment. The executive summary and overall conclusions did not accurately reflect the scientific evidence available. Independence is needed from the International Commission on Non-Ionizing Radiation Protection (ICNIRP), the group that set the exposure guidelines being assessed. This conflict of interest critically needs to be addressed for the forthcoming World Health Organisation (WHO) Environmental Health Criteria Monograph on Radiofrequency Fields. Decision makers, organisations and individuals require accurate information about the safety of RF electromagnetic signals if they are to be able to fulfil their safeguarding responsibilities and protect those for whom they have legal responsibility.

Thirty-minutes’ exposure to smartphone call triggers neutrophil activation in vitro

Background:

Despite accumulating evidence about the negative health effects of exposure to electromagnetic fields emitted by mobile phones, no information is available on the potential impact of radiofrequency (RF) waves on polymorphonuclear leukocytes biology.

Methods:

Two sequential whole blood tubes were collected from 16 ostensibly healthy volunteers. After placing the former tube of each subject in a plastic rack, 1 cm from a commercial smartphone (carrier frequency, 900 MHz), a call was placed on the smartphone and a communication lasting 30 min was manually activated. The latter blood tube of each volunteer was placed in another plastic rack, for an identical period of time, avoiding close contact with sources of RF waves. A complete blood count was then assessed in all whole blood samples, using Advia 2120.

Results:

The 30-min exposure of blood to RF waves did not induce significant variations of total and differential leukocyte counts. A significant decrease was however observed for many neutrophils parameters, with median percentage variation of −3.9% for the lobularity index (LI), −29.8% for the myeloperoxidase index (MPXI), −0.6% for the neutrophil cluster mean x (NEUTx) and −0.7% for the neutrophil cluster mean y (NEUTy), respectively. The percentage of blood samples with reduced values after exposure to RF waves was 81% for LI, 88% for NEUTx and 100% for both MPXI and NEUTy.

Conclusions:

The results of this study show that exposure to smartphone RF waves triggers activation of neutrophils in vitro, as mirrored by the significant variations observed in many activation parameters in Advia 2120.

Effect of a 2.45-GHz radiofrequency electromagnetic field on neutrophil chemotaxis and phagocytosis in differentiated human HL-60 cells

The potential public health risks of radiofrequency (RF) fields have been discussed at length, especially with the use of mobile phones spreading extensively throughout the world. In order to investigate the properties of RF fields, we examined the effect of 2.45-GHz RF fields at the specific absorption rate (SAR) of 2 and 10 W/kg for 4 and 24 h on neutrophil chemotaxis and phagocytosis in differentiated human HL-60 cells. Neutrophil chemotaxis was not affected by RF-field exposure, and subsequent phagocytosis was not affected either compared with that under sham exposure conditions. These studies demonstrated an initial immune response in the human body exposed to 2.45-GHz RF fields at the SAR of 2 W/kg, which is the maximum value recommended by the International Commission for Non-Ionizing Radiation Protection (ICNIRP) guidelines. The results of our experiments for RF-field exposure at an SAR under 10 W/kg showed very little or no effects on either chemotaxis or phagocytosis in neutrophil-like human HL-60 cells.

Microfluidic device for studying cell migration in single or co-existing chemical gradients and electric fields

Cell migration is involved in physiological processes such as wound healing, host defense, and cancer metastasis. The movement of various cell types can be directed by chemical gradients (i.e., chemotaxis). In addition to chemotaxis, many cell types can respond to direct current electric fields (dcEF) by migrating to either the cathode or the anode of the field (i.e., electrotaxis). In tissues, physiological chemical gradients and dcEF can potentially co-exist and the two guiding mechanisms may direct cell migration in a coordinated manner. Recently, microfluidic devices that can precisely configure chemical gradients or dcEF have been increasingly developed and used for chemotaxis and electrotaxis studies. However, a microfluidic device that can configure controlled co-existing chemical gradients and dcEF that would allow quantitative cell migration analysis in complex electrochemical guiding environments is not available. In this study, we developed a polydimethylsiloxane-based microfluidic device that can generate better controlled single or co-existing chemical gradients and dcEF. Using this device, we showed chemotactic migration of T cells toward a chemokine CCL19 gradient or electrotactic migration toward the cathode of an applied dcEF. Furthermore, T cells migrated more strongly toward the cathode of a dcEF in the presence of a competing CCL19 gradient, suggesting the higher electrotactic attraction. Taken together, the developed microfluidic device offers a new experimental tool for studying chemical and electrical guidance for cell migration, and our current results with T cells provide interesting new insights of immune cell migration in complex guiding environments.