Sunday, June 23, 2019

Recent Research on Wireless Radiation and Electromagnetic Fields

I have been circulating abstracts of newly-published scientific papers on wireless radiation and electromagnetic fields (EMF) about once or twice a month since August, 2016. These updates are sent to several hundred EMF scientists around the world.

The latest additions appear below. The complete collection of abstracts now covers more than 700 scientific papers. This 494-page document (pdf) can be downloaded by clicking on the following link:

http://bit.ly/190623EMF
Note: This link will change when new abstracts are added to the collection.

Latest Additions

Effects of RF‐EMF on the Human Resting‐State EEG—the Inconsistencies in the Consistency. Part 1: Non‐Exposure‐Related Limitations of Comparability Between Studies

Danker‐Hopfe H, Eggert T, Dorn H, Sauter C. Effects of RF‐EMF on the Human Resting‐State EEG—the Inconsistencies in the Consistency. Part 1: Non‐Exposure‐Related Limitations of Comparability Between Studies. Bioelectromagnetics. Published online June 18, 2019. https://doi.org/10.1002/bem.22194

Abstract

The results of studies on possible effects of radiofrequency electromagnetic fields (RF‐EMFs) on human waking electroencephalography (EEG) have been quite heterogeneous. In the majority of studies, changes in the alpha‐frequency range in subjects who were exposed to different signals of mobile phone‐related EMF sources were observed, whereas other studies did not report any effects. In this review, possible reasons for these inconsistencies are presented and recommendations for future waking EEG studies are made. The physiological basis of underlying brain activity, and the technical requirements and framework conditions for conducting and analyzing the human resting‐state EEG are discussed. Peer‐reviewed articles on possible effects of EMF on waking EEG were evaluated with regard to non‐exposure‐related confounding factors. Recommendations derived from international guidelines on the analysis and reporting of findings are proposed to achieve comparability in future studies. In total, 22 peer‐reviewed studies on possible RF‐EMF effects on human resting‐state EEG were analyzed. EEG power in the alpha frequency range was reported to be increased in 10, decreased in four, and not affected in eight studies. All reviewed studies differ in several ways in terms of the methodologies applied, which might contribute to different results and conclusions about the impact of EMF on human resting‐state EEG. A discussion of various study protocols and different outcome parameters prevents a scientifically sound statement on the impact of RF‐EMF on human brain activity in resting‐state EEG. Further studies which apply comparable, standardized study protocols are recommended.

Open access paper: https://onlinelibrary.wiley.com/doi/full/10.1002/bem.22194

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Relationship between the use of electronic devices and susceptibility to multiple sclerosis

Khaki-Khatibi F, Nourazarian A, Ahmadi F, Farhoudi M, Savadi-Oskouei D, Pourostadi M, Asgharzadeh M. Relationship between the use of electronic devices and susceptibility to multiple sclerosis. Cogn Neurodyn. 2019 Jun;13(3):287-292. doi: 10.1007/s11571-019-09524-1.

Abstract

Multiple sclerosis (MS) is an autoimmune condition influenced by both genetic and environmental factors. Dirty electricity generated by electronic equipment is one of the environmental factors that may directly or indirectly impact MS susceptibility. The current Study aimed to evaluate the relationship between the usage time of electronic equipment and susceptibility to MS in North-West Iranian people. This approach was carried out upon 471 MS-diagnosed patients and 453 healthy participants as control group in East Province of Azerbaijan. By utilizing structured questionnaires, the information of all participants about usage status of some electronic devices was obtained. Data were analyzed by IBM SPSS Statistics version 18.0 and the quantitative variables were analyzed by Chi Square and Independent sample t tests. P values below or equal to 0.05 were considered as significant. Among the evaluated items in this approach, the utilization of cell phones and satellite television dishes were significantly higher in MS patients (p < 0.001, p = 0.07). Furthermore, a correlation was observed between sleeping with cell phone and/or laptop under the pillow (p = 0.011) and MS disease; however, there was no significant differences between MS patients and controls in computer using and television watching. Our study reinforces the concept that the utilization of some electronic devices and the continuous exposure to dirty electricity would increase the risk of MS disease thereupon by enhancing the cognizance of adverse effects of dirty electricity and reducing the time spent over electronic devices during adolescence and adulthood the occurrence probability of MS could be declined.

https://www.ncbi.nlm.nih.gov/pubmed/31168332

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Electromagnetic exposure from mobile phones in a city like environment: The case study of Leuven, Belgium

Iyare RN, Volskiy V, Vandenbosch GAE. Study of the electromagnetic exposure from mobile phones in a city like environment: The case study of Leuven, Belgium. Environmental Research. Available online 26 May 2019. https://doi.org/10.1016/j.envres.2019.05.029

Highlights

• Mobile phone (MP) exposure values are far above the exposures due to base stations.
• MP exposure is considerably higher for indoor environments compared to outdoor.
• Exposure is lower for locations close to base stations than locations further away.
• All exposures are in compliance with the SAR limit recommended by ICNIRP.

Abstract

A measuring campaign for the assessment of electromagnetic exposure levels from mobile phones in the city center of Leuven, Belgium, has been carried out. The main objective of the assessment is to study the dependency of the exposure of the user by his own mobile phone in terms of location in the city (very close to base stations and at randomly selected locations). The measurements were performed in both public and private areas in 60 outdoor and 60 indoor locations in Leuven. The campaign was focused on GSM 900 mobile communications. The results show that the exposure is considerably higher for indoor environments compared to outdoor environments, and at the randomly chosen locations compared to locations very close to base stations. However, the most important observation is that the average outdoor exposure in Leuven of the user of a mobile phone is about 8 times higher than the average outdoor exposure by base stations. Indoors, this factor rises to about 30.

Excerpts

All results obtained in this measurement campaign are for a mobile phone with an active connection (a voice call). Field values were obtained through an app installed on
a mobile phone. The app called Quanta pro [48] (shown in Figure 1) gets active (records the emissions from the mobile phone) immediately when a call is made with the mobile phone. This means that RF exposures were obtained during typical phone usage. During the exposure measurement, the mobile phone user makes a phone call of six minutes duration at a specific point in the measurement environment while the app concurrently keeps track of the power values transmitted by the antenna of the mobile phone.

Conclusions:  The electromagnetic radiation exposure from mobile phones operating under GSM 900 in a typical city center, Leuven, Belgium, was assessed using a calibrated app installed on a representative mobile (smart) phone. The calibration was performed with a highly accurate spectrum analyzer based set-up. The levels averaged over the city center are: outdoors about 5.54 and 6.18 V/m for locations near base stations and arbitrarily chosen locations, respectively, and indoors about 10.36 and 30.87 V/m, also for locations near base stations and arbitrarily chosen locations, respectively. To the average, near base stations the indoor exposure is about a factor of two higher than the outdoor exposure. This smaller factor is due to the fact that the indoor exposure was measured at higher floors of buildings. At arbitrary locations the indoor exposure is about a factor of five higher than the outdoor exposure. These measurements were always done at floor level. All measured values are far above the values typically measured for the exposure due to base stations, even far above the maximum exposure level defined in the norm in Flanders, which is 3 V/m per antenna at 900 MHz. It can easily be concluded that the deployment of infrastructure, typically in the form of microcells, hotspots or distributed relays, should aim at minimizing mobile phone exposure and not necessarily the exposure by the base station itself. This may require a paradigm shift in the public opinion.



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Personal RF-EMF exposure from mobile phone base stations during temporary events


Ramirez-Vazquez R, Gonzalez-Rubio J, Arribas E, Najera A.Personal RF-EMF exposure from mobile phone base stations during temporary events. Environ Res. 2019 May 21;175:266-273. doi: 10.1016/j.envres.2019.05.033.

Abstract

BACKGROUND: In recent years, radiofrequency electromagnetic fields (RF-EMF) exposure has increased owing to new communication technologies. Simultaneously, increased exposure to RF-EMF has led to society's growing concern about the possible effects they may have on human health. Many studies have described personal RF-EMF exposure by using personal exposimeters to know a population's daily exposure to mobile phone base stations and to other sources whose installations tend to be permanent. Nonetheless during special events like concerts or fairs, where many people gather, permanent installations might not suffice to cover demand. So telephone companies install temporary stations for these events, and modify the exposure pattern of these areas or populations.

OBJECTIVE: To study if installing temporary antennae for large events, and high concentrations of mobile phones, modify the exposure pattern compared to usual situations.

METHODS: Personal RF-EMF exposure from mobile phones (uplink) and mobile phone base stations (downlink) installed at the 2017 Albacete Fair (Spain) was recorded. Between 7 and 17 September, more than 2,500,000 people visited this Fair. Measurements were taken by two Satimo EME SPY 140 personal exposimeters, placed one each side of a research team member's waist. These exposimeters were programmed to take measurements every 4 s at different time of day; morning, afternoon and night; and in several places, around the Fair Enclosure (zones Ejidos and Paseo) and inside the enclosure (Interior). These measurements were repeated on a weekday, at the weekend and the day after the Fair ended after temporary base stations had been removed. They were also taken for 1 h in all three zones, for each time of day; that is, 9 h were recorded for each study day.

RESULTS: The mean RF-EMF recorded exposure from base stations (downlink-DL) on the days the Fair opened (morning, afternoon and night) for the three studied zones was 791.8 μW/m2, while the exposure produced by mobile phones (uplink-UL) was 59.0 μW/m2. These values were 391.2 μW/m2 (DL) and 10.3 μW/m2 (UL) a few days after the event ended. In study zones Ejidos and Paseo, both outside, the highest mean exposure was recorded at the weekend as 1494.1 and 848.1 μW/m2 respectively. For the Interior zone, the mean value recorded during the Fair was 354.8 μW/m2. These values contrast with those recorded in the three zones after the event ended: 556.37 (Ejidos), 144.1 (Paseo); 473.21 μW/m2 (Interior). The fact that the mean exposure recorded at Interior was slightly higher after the Fair could be due to signal shielding by so many people. The reduction in exposure in Paseo after the Fair was outstanding, probably due to the antennae being placed on low towers. Major differences were also found in the RF-EMF exposure from UL. In this case, the weekend values taken during the Fair were between 28.2 μW/m2 at Interior (weekday) and 98.1 μW/m2 at Ejidos (weekend), which dropped to 5.5 at Paseo after the Fair, to 11.7 μW/m2 at Interior and to 13.6 μW/m2 at Ejidos.

CONCLUSIONS: Installing mobile phone base stations, and a dense public using mobile phones, imply a significant increase in personal RF-EMF exposure compared to that recorded during normal periods in the same area. However, the recorded measurements were below legally established limits.

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Emissions From Smart Meters and Other Residential Radiofrequency Sources

Aerts S, Verloock L, Van den Bossche M, Martens L, Vergara X, Joseph W. Emissions From Smart Meters and Other Residential Radiofrequency Sources. Health Phys. 2019 Jun;116(6):776-788. doi: 10.1097/HP.0000000000001032.

Abstract

The advent of the Internet of things comes with a huge increase in wirelessly communicating devices in our environment. For example, smart energy-consumption meters are being widely deployed in residences from which they communicate their state using radiofrequency networks. Accurate characterization of the radiofrequency emissions from emerging residential wireless solutions is important to inform the public about the potential impact on their exposure to radiofrequency electromagnetic fields. A new measurement procedure to determine the exposure from residential radiofrequency devices is proposed by assessing the peak emitted fields at various distances and the proportion of time they transmit (duty cycle). Radiofrequency emissions from 55 residential devices were measured in 10 residences (Belgium and France) and compared to environmental levels, emissions from 41 mobile phones, and international standards. Overall, residential levels of radiofrequency electromagnetic field exposure are low. In addition to the continuous environmental exposure, wireless access points (due to frequent use) and especially mobile phones and other personal communication devices (due to their use close to the body) continue to represent the bulk of the radiofrequency electromagnetic field exposure in the smart home. However, some residential devices can significantly increase the exposure if their duty cycles are high enough (>10%), especially when held or used close to the body. Individual smart meters, on the other hand, will contribute only little in general, despite emissions of up to 20 V m at 50 cm, due to their low duty cycles (maximum 1%) and locations.

https://www.ncbi.nlm.nih.gov/pubmed/30883437

Conclusions

In this study, a novel measurement method was designed to characterize in situ residential RF emissions from emerging wireless solutions (e.g., IoT sources and smart meters) by determining the RF transmission frequency, the peak emitted fields at various distances, and the proportion of transmission time (i.e., duty cycle), for which the spectrogram mode of a spectrum analyzer was used. This method was applied to a convenience sample of 10 residences in Belgium and France containing, in total, 55 IoT devices, smart meters, and other RF-emitting devices. The measured emissions were also compared to present levels of telecommunications and broadcasting signals, emissions by a mobile phone using three current telecommunications technologies (GSM, UMTS, and LTE), as well as to the ICNIRP guidelines for general public RF-EMF exposure.
Overall, low to very low emissions were measured for nearly all of the devices, and it is concluded that, in addition to the continuous exposure due to environmental sources, when used, wireless access points and especially mobile phones and other personal communication devices (e.g., DECT cordless phones, walkie-talkies) will continue to represent the bulk of our exposure to radiofrequency electromagnetic fields in the smart home, due to their typically high emissions and use close to the body. However, RF-emitting devices with high duty cycles (e.g., in this sample, motion sensor, baby monitor, and an IoT toothbrush) may significantly increase the potential for exposure, especially when used or located close to the body. The potential impact on the exposure due to individual smart meters, on the other hand, and in particular due to the communications modules wirelessly linked to a utility company’s central network, is small, regardless of their emissions of up to 20 V m−1 at 0.2 m, given their rare transmissions and usual deployment away from the residents.

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Assessment of Personal Occupational Exposure to RF EMF in Libraries and Media Libraries, Using Calibrated On-Body Exposimeters

Massardier-Pilonchery A, Nerrière E, Croidieu S, Ndagijimana F, Gaudaire F, Martinsons C, Noé N, Hours M. Assessment of Personal Occupational Exposure to Radiofrequency Electromagnetic Fields in Libraries and Media Libraries, Using Calibrated On-Body Exposimeters. Int. J. Environ. Res. Public Health 2019, 16(12), 2087; https://doi.org/10.3390/ijerph16122087.

Abstract

Background and Objectives: With the spread of Wifi networks, safety concerns have arisen, with complaints of somatic disorders, notably in traditional libraries and media libraries. The aim of the present study was to describe the conditions and levels of exposure to radiofrequency electromagnetic fields in the real-life occupational conditions of those working in traditional libraries and media libraries.

Methods: Dynamic measurements, using an exposimeter, were taken in 20 radiofrequency bands from 88 to 5850 MHz. The activity of 28 library workers was analyzed on a space-time budget. An audit of exposure sources and static measurements enabled the work-places to be mapped.

Results: In seven libraries, 78,858 samples were taken over the 20 radiofrequency bands from 88 to 5850 MHz. Exposure was described for 28 working days. The median total field was 0.071 V/m (10th percentile: 0.022 V/m, 90th percentile: 0.534 V/m) and for Wifi the median field was 0.005 V/m (10th percentile: 0.005 V/m, 90th percentile: 0.028 V/m). Median individual exposure to Wifi frequency waves ranged from 0.005 to 0.040 V/m.

Conclusions: Overall, the occupational exposure in this sector was close to the exposure in the general population. Peaks were due to the use of walkie-talkies by security staff. Exposure due to external sources depended on geographic location. Exposure in this occupation is well below the general occupational exposure levels, notably as regards Wifi.

Conclusions

The aim of this study was to assess electromagnetic exposure of employees in libraries, notably, to Wifi.

On average, occupational exposure in this branch is close to that of the general population. The highest peaks were associated with walkie-talkie use by security staff. Exposure to outside sources depended on the geographic location. Employees’ exposure was largely below the occupational norms, notably as regards Wifi. Static exposure from radiofrequency outdoor emissions (UMTS, GSTM) and from indoor Wifi spots is found to be 10 times lower than electromagnetic limit values defined by ICNIRP.

The exposure of workers to electromagnetic fields is rarely explored by occupational practitioners due to a lack of methodology to perform this evaluation. The present methodology for describing exposure could be transposed to other occupational radiofrequency exposure contexts, given persisting doubts about the health risks involved and the current legislation.

What is New in This Paper?

Exposure to radiofrequency electromagnetic fields due to new technologies in the real-life occupational conditions in library and media libraries is not well characterized. This study finds an exposure close to the general population. However, high peaks were due to the use of walkie-talkies by security staff. Exposure due to external sources depended on geographic location.


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An Extremely Safe Low-SAR Antenna with Study of Its Electromagnetic Biological Effects on Human Head 

Nazeri A, Abdolali A, Mehdi M. An extremely safe low-SAR antenna with study of its electromagnetic biological effects on human head. Wireless Personal Communications. 1-14. Published online May 17, 2019. https://doi.org/10.1007/s11277-019-06621-6

Abstract
In this paper, a new low-Specific Absorption Rate (SAR) antenna is proposed for the sake of safe communication in all situations. The proposed antenna involves a Microstrip patch antenna and a metallic casing loop which leads to SAR reduction. The structure operates at 0.9 GHz and 2.4 GHz which produces 0.52 W/kg and 0.25 W/kg SAR value on the human head, respectively. Then, in order to guarantee the antenna safety feature, the experiments are carried out when the human wear an earring. The impact of metallic earrings in different sizes on SAR distribution is investigated. Also, the antenna orientation and rotation effect is considered in detail. It is concluded that the change of Antenna position or use of metallic earrings makes an extremely significant impact on SAR value. But, the results of the presented antenna demonstrate that the produced SAR value in all positions, do not exceed the safe rate. It makes the antenna a suitable candidate for employing in most telecommunication applications.
Conclusions
In this paper, a novel low-SAR Microstrip Antenna for using in a safe communication is designed. The proposed antenna produces 0.52 W/kg and 0.25 W/kg SAR value on the head at 0.9 and 2.4 GHz. The antenna is created of a microstrip patch and a metallic loop. An extensive study is accomplished on the destructive effects of EM-waves on the human body. Also, the effect of the human head on the antenna performance is investigated. In addition, earrings with several different sizes are employed to consider the cases which make the worst destructive effect on the human head. The effect of antenna rotation and changes in its orientation is studied as well. It is concluded that antenna rotation causes a significant impact on SAR value when earrings are used. At last, this study guarantees that the presented antenna make a safe SAR for most of the situations.
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Effects of Radiofrequency Exposure and Co-Exposure on Human Lymphocytes: Influence of Signal Modulation and Bandwidth

Romeo S, Sannino A, Zeni O, Angrisani L, Mass R, Scarfi MR. Effects of radiofrequency exposure and co-exposure on human lymphocytes: The influence of signal modulation and bandwidth. IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, May 20, 2019.  DOI: 10.1109/JERM.2019.2918023

Abstract

The occurrence of modulation-specific effects after co-exposures to Radiofrequency (RF) and other agents has been discussed in the literature. In this paper, the influence of modulation and bandwidth in eliciting the DNA damage of RF alone and in combination with mitomycin-C (MMC), is analyzed in human lymphocytes. Blood cultures from healthy donors were exposed to 1950 MHz, and Continuous Wave (CW), Wideband Direct-Sequence Code Division Multiple Access (WCDMA, 4.5 MHz bandwidth), and Additive White Gaussian Noise (AWGN, 9 MHz bandwidth) signals were considered. For each signal, SAR values of 0.15, 0.3, 0.6, 1.25 W/kg were tested. RF exposure alone never induced DNA damage in the micronucleus assay. When RF exposure was followed by MMC treatment, the effect depended on modulation and bandwidth. CW exposure never altered the MMC-induced DNA damage, while such damage was reduced when either signals WCDMA at 0.3 W/kg SAR or AWGN at 0.15 and 0.3 W/kg were applied. These results indicate the influence of modulation for the occurrence of the protective effect, with a relation between the bandwidth and the power absorbed by samples. If confirmed in vivo, clinical applications using modulated RF signals could be devised, to protect cells from side effects of therapeutic treatments.

RF electromagnetic fields reduce the DNA damage induced by the chemical agent Mitomycin-C (MMC) in human lymphocytes. The effect is dependent on signal modulation and bandwidth.

Conclusions

The results of the present investigation provide further evidence that RF exposure can prompt a protective effect in mammalian cells against subsequent genotoxic insults. Moreover, in the current experimental conditions, taking advantage of a systematic comparison with the CW exposure, our findings highlight the modulation scheme and the signal bandwidth as crucial factors for the occurrence of the protective effect.

Having said the above, if proved in in vivo models, a new research horizon lies ahead of us, as a potential, innovative clinical application of RF electromagnetic fields, exploiting the protective effect, could be proved. In radio-biology the AR phenomenon has been proposed as a way to protect healthy cells from side effects of chemo/radio-therapeutic treatments, by pre-treatments with low doses of ionizing radiation. However, such proposal never moved into clinical practice due to the risk of cellular transformation as a biological consequence of protracted, low-dose rate exposures to ionizing radiation [35]. The possibility of inducing AR by RF pre-treatments may overcome this issue, due to the non-ionizing nature of these fields. Moreover, RF-induced protection has been here proved to be a tunable phenomenon de-pending on the electromagnetic conditions adopted, which could be able to target different cell types located at different depths in the body. In addition, potential biomedical applications exploiting the protective effect of RF could benefit from the availability of commercially established, low-cost RF sources.

Take-Home Messages

The innovative feature of RF electromagnetic fields shown here, consists in offering protection to human cells against the damaging action of a chemical agent.

The protective effect of RF electromagnetic fields occurs in presence of modulated signals and depends on signal bandwidth, as well as on SAR level.

RF-induced protective effect has been here proved, on an in vitro model, to be a tunable phenomenon depending on the electromagnetic conditions adopted, which provides a step towards applications targeting cells located at different depths in the body.
These findings suggest the existence of a complex interaction between modulated RF fields and biological systems. Such interaction becomes detectable when samples are appropriately sensitized, such as when RF exposure is combined with other chemical or physical treatments.


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Thermal Analysis Complementary to Standardized Experimental Dosimetry of SAR in Human Head


Ilie-Săndoiu AM, Morega M, Morega AM. Thermal Analysis Complementary to Standardized  Experimental Dosimetry of SAR in Human Head.  2019 11th International Symposium on Advanced Topics in Electrical Engineering (ATEE). 28-20 March 2019. DOI: 10.1109/ATEE.2019.8724859

Abstract

Cellular phones (CPs) intensive, long-term usage may raise concerns regarding collateral effects such as hyperthermia through direct exposure to electromagnetic field, and direct thermal contact to the outer ear.Among other methods used to evaluate the thermal menace posed by CPs, the physical experiments, conducted on equivalent phantoms play an important role. Replacing the head content with biologically–equivalent fluid is considered to provide for satisfactory experimental conditions with the aim to assess realistic "specific energy absorption rate" (SAR) levels and the pending thermal load. Moreover, numerical experiments may complement physical experiments, strengthening the predictive consistency of this already standardized lab approach.A numerical model of the human head and radiation source is designed and validated in compliance with experimental electromagnetic dosimetry standards with the aim of extending and processing useful information from limited experimental output. The current study goes further by exploring the  heat absorption from the CP used nearby the head, making use of numerical simulation of the coupled electromagnetic and thermal problems, applied on models with varying degrees of realism. The analysis presented here concentrates on the assessment of cumulative contributions - energy absorption through SAR and direct contact with the heated CP device - on raising the temperature.

Conclusions

Present work shows some results from a numerical study performed on a phantom-like head model, the SAM head, described by international standards that are used for the certification of mobile phone devices [6], [7]. This benchmark numerical model was initially developed and validated through experiment for SAR dosimetry [8], but its applicability is extended here for heating estimates. A combined thermal dosimetry analysis is performed, taking two heating sources into account, i.e. the well-documented temperature rise from radiofrequency power absorption and additional warming from direct contact of the ear with the casing of the phone (heated by power dissipation inside the device). The results show a highly non-uniform distribution of the temperature inside the target volume, as much as a slight increase of the local temperature on the hot spots, due to the additional ear surface warming.

One could see that all the analysis was performed on a very simplified numerical model, if compared against true anatomy and functionality of the human head (i.e. non-homogeneous  anatomical structure with specific physical properties and energy transfer under the influence of subtle physiology mechanisms – metabolism, blood perfusion); realistic conditions could bring substantial differences. However, the cumulative effect of the heating sources is a reality; it depends on the emitted power and complexity of the phone and operation conditions and it is commonly sensed during long conversations because it creates discomfort to the phone user. This aspect needs to be considered more carefully in the assessment of bio-thermal effects and human protection.


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Evaluation of the Effect of Cellular Phones on Salivary Levels of IL-10

Pedrami A, Arbabi-Kalati F. Evaluation of the Effect of Cellular Phones on Salivary Levels of IL-10. Iran J Public Health. 2019 Feb; 48(2): 367–368.

No abstract.


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Glioma incidence and survival variations by county-level socioeconomic measures


Cote DJ, Ostrom QT, Gittleman H, Duncan KR, CreveCoeur T, Kruchko C, Smith TR, Stampfer MJ, Barnholtz-Sloan J. Glioma incidence and survival variations by county-level socioeconomic measures. Cancer. 2019 Jun 17. doi: 10.1002/cncr.32328.

Abstract

BACKGROUND:  Multiple studies have reported higher rates of glioma in areas with higher socioeconomic status (SES) but to the authors' knowledge have not stratified by other factors, including race/ethnicity or urban versus rural location.

METHODS: The authors identified the average annual age-adjusted incidence rates and calculated hazard ratios for death for gliomas of various subtypes, stratified by a county-level index for SES, race/ethnicity, US region, and rural versus urban status.

RESULTS: Rates of glioma were highest in counties with higher SES (rate ratio, 1.18; 95% CI, 1.15-1.22 comparing the highest with the lowest quintiles [P < .001]). Stratified by race/ethnicity, higher rates in high SES counties persisted for white non-Hispanic individuals. Stratified by rural versus urban status, differences in incidence by SES were more pronounced among urban counties. Survival was higher for residents of high SES counties after adjustment for age and extent of surgical resection (hazard ratio, 0.82; 95% CI, 0.76-0.87 comparing the highest with the lowest quintile of SES [P < .001]). Survival was higher among white Hispanic, black, and Asian/Pacific Islander individuals compared with white non-Hispanic individuals, after adjustment for age, SES, and extent of surgical resection, and when restricted to those individuals with glioblastoma who received radiation and chemotherapy.

CONCLUSIONS: The incidence of glioma was higher in US counties of high compared with low SES. These differences were most pronounced among white non-Hispanic individuals and white Hispanic individuals residing in urban areas. Better survival was observed in high SES counties, even when adjusting for extent of surgical resection, and when restricted to those who received radiation and chemotherapy for glioblastoma. Differences in incidence and survival were associated with SES and race, rather than rural versus urban status.

Conflict of Interest Disclosures Quinn T. Ostrom was supported by a Research Training Grant from the Cancer Prevention and Research Institute of Texas (RP160097T). Meir J. Stampfer has served as a paid expert witness for Verizon (represented by the Alston Bird Law firm) in a lawsuit regarding the alleged link between cell phones and brain cancer for work performed outside of the current study. The law firm and company had no knowledge of or influence on the current study. The other authors made no disclosures.


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Controversies around electromagnetic fields and electromagnetic hypersensitivity. The construction of "low noise" public problems

Dieudonné M. [Controversies around electromagnetic fields and electromagnetic hypersensitivity. The construction of "low noise" public problems]. [Article in French] . Sante Publique. 2019 January February;Vol. 31(1):43-51. doi: 10.3917/spub.191.0043.

Abstract

For two decades, health effects of electromagnetic fields (EMF) and electromagnetic hypersensitivity (EHS) have become increasingly controversial topics in France. They constitute "low noise" public problems, whose construction seems impossible to complete : they can neither be eliminated from the political agenda nor durably included. This article analyses the political process leading to this situation using qualitative data. In line with previous studies of the dispute surrounding mobile phone base stations, it shows how the controversy around EMF health effects emerged from an urban planning problem subsequently converted into a public health issue. This conversion gave rise to a spin-off controversy surrounding EHS, which quickly grew to become a controversy of its own. The study of these controversies reveals how the democracy crisis affecting public risk management increases the risk of false health alarms. It also explains why EHS fails to get as medically recognized as other functional somatic syndromes, like fibromyalgia. Medically unexplained symptoms thus appear likely to contribute significantly to health controversies.


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Chronotoxicity of 1.8 GHz radio-frequency radiation on plasma stress hormones and immune factors in mice

Qin F, Shen T, Li J, Xu B, Chen Y, Zheng ZA, Zou D. [Chronotoxicity of 1.8 GHz radio-frequency radiation on plasma stress hormones and immune factors in mice]. [Article in Chinese]. Wei Sheng Yan Jiu. 2019 May;48(3):482-487.

Abstract

OBJECTIVE: To study the chronotoxicity of radio-frequency radiation(RF) on the plasma stress hormones and immune factors in mice.

METHODS: A total of 72 healthy C57 BL mice with circadian rhythm were divided into twelve groups: 6 Sham group and 6 RF groups. RF groups were exposed to 1.8 GHz RF at 226 μW/cm~2 for 60 days with 2 h/day respectively at corresponding zeitgeber time(ZT 0:00, ZT 4:00, ZT 8:00, ZT 12:00, ZT 16:00, ZT 20:00). The Sham group mice were exposed to the same condition without electromagnetic signal. At the end of last RF exposure, blood samples were collected from each animal. The concentrations of plasma stress hormones(ACTH, CORT) and immune factors(GM-CSF, TNF-α) were determined by enzyme linked immunosorbent assay(ELISA) method.

RESULTS: The daily average levels of ACTH, CORT, GM-CSF and TNF-α were 84.12, 60.14, 1112.02 and 594.49 ng/L, which were decreased to 62.07, 41.21, 84.18 and 305.08 ng/L after 60 days of RF exposure. Compared to sham-exposed animals, the daily average levels of ACTH, CORT, GM-CSF and TNF-α were all significantly decreased(P<0.05). Circadian rhythms in the secreting of CORT, GM-CSF, TNF-α were disappeared(P>0.05), circadian rhythms of ACTH was shifted in RF-exposed mice, with the amplitude reduced from 12.45 to 4.88 and peak time postponed from 1:39 to 5:29.

CONCLUSION: 1.8 GHz RF may weaken the function of stress and immune, and disturb their circadian rhythmicities.


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Sensitivity of EMF effects on childhood leukemia to confounding by residential mobility

Amoon AT, Arah OA, Kheifets L. The sensitivity of reported effects of EMF on childhood leukemia to uncontrolled confounding by residential mobility: a hybrid simulation study and an empirical analysis using CAPS data. Cancer Causes Control. 2019 May 29. doi: 10.1007/s10552-019-01189-9.

Abstract

PURPOSE: Residential mobility is considered as a potential source of confounding in studies assessing environmental exposures, including in studies of electromagnetic field (EMF) exposures and childhood leukemia.

METHODS: We present a hybrid simulation study where we simulate a synthetic dataset based on an existing study and use it to assess the sensitivity of EMF-leukemia associations to different scenarios of uncontrolled confounding by mobility under two major hypotheses of the infectious etiology of childhood leukemia. We then used the findings to conduct sensitivity analysis and empirically offset the potential bias due to unmeasured mobility in the California Power Line Study dataset.

RESULTS: As expected, the stronger the assumed relationship between mobility and exposure and outcome, the greater the potential bias. However, no scenario created a bias strong enough to completely explain away previously observed associations.

CONCLUSIONS: We conclude that uncontrolled confounding by residential mobility had some impact on the estimated effect of EMF exposures on childhood leukemia, but that it was unlikely to be the primary explanation behind previously observed largely consistent, but unexplained associations.


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Amplitude-modulated RF EMF blocks growth of hepatocellular carcinoma via voltage-gated calcium channels and calcium ion influx

Jimenez H, Wang M, Zimmerman JW, et al. ..., Blackman CF, Pasche BC. Tumour-specific amplitude-modulated radiofrequency electromagnetic fields induce differentiation of hepatocellular carcinoma via targeting Cav3.2 T-type voltage-gated calcium channels and Ca2+ influx. EBioMedicine. 2019 May 24. pii: S2352-3964(19)30342-1. doi: 10.1016/j.ebiom.2019.05.034. [Epub ahead of print]

Abstract

BACKGROUND: Administration of amplitude modulated 27·12 MHz radiofrequency electromagnetic fields (AM RF EMF) by means of a spoon-shaped applicator placed on the patient's tongue is a newly approved treatment for advanced hepatocellular carcinoma (HCC). The mechanism of action of tumour-specific AM RF EMF is largely unknown.

METHODS: Whole body and organ-specific human dosimetry analyses were performed. Mice carrying human HCC xenografts were exposed to AM RF EMF using a small animal AM RF EMF exposure system replicating human dosimetry and exposure time. We performed histological analysis of tumours following exposure to AM RF EMF. Using an agnostic genomic approach, we characterized the mechanism of action of AM RF EMF.

FINDINGS: Intrabuccal administration results in systemic delivery of athermal AM RF EMF from head to toe at levels lower than those generated by cell phones held close to the body. Tumour shrinkage results from differentiation of HCC cells into quiescent cells with spindle morphology. AM RF EMF targeted antiproliferative effects and cancer stem cell inhibiting effects are mediated by Ca2+ influx through Cav3·2 T-type voltage-gated calcium channels (CACNA1H) resulting in increased intracellular calcium concentration within HCC cells only.

INTERPRETATION: Intrabuccally-administered AM RF EMF is a systemic therapy that selectively block the growth of HCC cells. AM RF EMF pronounced inhibitory effects on cancer stem cells may explain the exceptionally long responses observed in several patients with advanced HCC.

FUND: Research reported in this publication was supported by the National Cancer Institute's Cancer Centre Support Grant award number P30CA012197 issued to the Wake Forest Baptist Comprehensive Cancer Centre (BP) and by funds from the Charles L. Spurr Professorship Fund (BP). DWG is supported by R01 AA016852 and P50 AA026117.

Open access paper: https://www.ebiomedicine.com/article/S2352-3964(19)30342-1/fulltext

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Synergistic Effect of Radiofrequency EMF of Dental Light Cure Devices and Mobile Phones Accelerates Microleakage of Amalgam Restorations

Mortazavi SMJ, Dehghani Nazhvani A, Paknahad M. Synergistic Effect of Radiofrequency Electromagnetic Fields of Dental Light Cure Devices and Mobile Phones Accelerates the Microleakage of Amalgam Restorations: An in vitro Study. J Biomed Phys Eng. 2019 Apr 1;9(2):227-232.

Abstract

Background: Previous studies have shown that exposure to electromagnetic fields produced by magnetic resonance imaging or mobile phones can lead to increased microleakage of dental amalgam.

Objective: The aim of the present study was to investigate the effect of electromagnetic field  of a commercial dental light cure device and a common GSM mobile phone on microleakage of amalgam restorations.

Materials and Methods: Identical class V cavities were prepared on the buccal surfaces of 60 non-carious extracted human teeth. The samples were randomly divided into 4 groups of 20 samples each. The samples in the first group were not exposed to electromagnetic fields, while the second and the third groups were exposed to electromagnetic fields produced by a commercial light cure device, or mobile phone radiation (60 min), respectively. The fourth group was exposed to electromagnetic radiations emitted by both mobile phone for 60 min and light cure device. Then, teeth samples were scored for microleakage according to a standard dye penetration protocol by examination under a stereomicroscope.

Results: The mean score of microleakage in the fourth group (light cure + mobile phone) was significantly higher than that of the control group (P =0.030). Moreover, the scores of microleakage in this group were significantly higher than that of the second group (light cure only) (P= 0.043).

Conclusion: Exposure of amalgam restorations to electromagnetic fields produced by both light cure devices and mobile phones can synergistically increase the microleakage of amalgam restorations.


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Significant Cellular Viability Dependence on Time Exposition at ELF-EMF and RF-EMF In Vitro Studies
García-Minguillán López  O, Jiménez Valbuena A, 2 Maestú Unturbe C. Significant Cellular Viability Dependence on Time Exposition at ELF-EMF and RF-EMF In Vitro Studies.  Int. J. Environ. Res. Public Health 2019, 16(12), 2085; https://doi.org/10.3390/ijerph16122085.

Abstract


The human concern about the effect of electromagnetic fields (EMFs) has changed over time from the effects produced by EMFs of extremely low frequencies (ELFs) to the effects produced by exposure to a radio frequency (RF), with concerns shifting toward EMFs due to the development of new technologies and forms of communication. Previous studies have analysed the effects produced at different frequencies without considering in detail the effect of the time of exposure. Therefore, in the present study, we analysed in vitro the effect produced by a 100 µT EMF at different ELFs and exposure times in glioblastomas, as well as the effect produced in a fibroblast by an RF-EMF of 2.54 GHz. Our results indicate a significant time dependence in cell viability of fibroblasts exposed to an RF-EMF of 2.54 GHz and a non-time-dependent effect in cell viability of glioblastomas exposed to an ELF-EMF, highlighting the possible relation between frequency and time of exposure.

Conclusions

In most of the in vitro studies that have been done with EMFs, the time of exposure has not been considered in detail, even though cellular responses, such as cell proliferation, viability and death, clearly vary between chronic and acute exposure.

Our results demonstrate a time dependence of NIH/3T3 cell viability when exposed to an RF-EMF of 2.54 GHz, which decreases with time to obtain a 71.12% decline in viability after 21 h of exposure.

On the other hand, our results for an ELF-EMF of 100 µT have demonstrated non-time-dependent effects. Frequency dependence effects were observed, obtaining a primary increase in cell viability at 50 Hz and a reduction in cell viability at 30 Hz, showing that even the recommended exposure level affects cell viability.

Therefore, the relationship between the frequency and time of exposure could determine the cellular response, demonstrating a need for further research.


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DNA effects of low level occupational exposure to extremely low frequency electromagnetic fields (50/60 Hz)


Zendehdel R, Yu IJ, Hajipour-Verdom B, Panjali Z. DNA effects of low level occupational exposure to extremely low frequency electromagnetic fields (50/60 Hz).
Toxicol Ind Health. 2019 May 28:748233719851697. doi: 10.1177/0748233719851697.

Abstract

AIMS: Exposure to extremely low frequency magnetic fields (ELF-MF) occurs from natural and artificial sources. Although ELF-MF has been classified as a suspected humans carcinogen agent by the International Agency for Research on Cancer, little is known of the effects of ELF-MF at lower exposure levels of the recommended range. In the present study, DNA damage in the peripheral blood cells of power line workers was investigated.

MATERIALS AND METHODS: Occupational exposure to ELF-MF in a power plant was measured using the National Institute for Occupational Safety and Health (NIOSH) manual. Single-strand breaks (SSBs) in DNA were evaluated in 29 male utility workers as the exposed population and 28 male support personnel as the control subjects using the comet assay. Effects of ELF-MF on subjects were evaluated using DNA percent in tails, tail length, olive length, and tail moment.

RESULTS: Occupational exposure levels to ELF-MF in the utility workers were less than the threshold limit values (TLV) recommended by the American Conference of Government Industrial Hygienist (ACGIH). The median value of the magnetic field at the working sites was 0.85 µT. Induction of DNA damage was observed for the exposed workers compared with the controls. Olive length, tail moment, and tail DNA percent increased significantly ( p < 0.05) in the utility workers.

CONCLUSIONS: Exposure to ELF-MF at levels less than the ACGIH exposure limit can produce DNA strand breaks.


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Impact of RF and LEDs on plants growth


Al Saadi A, ; Al Rashdi M, Al-Nassri H, Nadir Z, Khan M. Impact of RF and leds on plants growth. 7th Brunei International Conference on Engineering and Technology 2018 (BICET 2018). 12-14 Nov. 2018. DOI: 10.1049/cp.2018.1500.

Abstract

The agriculture sector is one of the most important sectors supporting the Gross National Product of many countries throughout globe. Improving the agricultural productivity with minimal natural resources is the possible solution to mitigate the worldwide food shortage. This paper discusses a new useful agricultural method by using electromagnetic fields to improve the seed germination and crop yields. Also, this study explored the possible impacts of LEDs with different colours to enhance seed germination. These applications may also have had a positive effect on increasing crop production in the longer term. This research focuses in studying the impact of electromagnetic field, red and blue LEDs on cucumber and marigold plants and analysing the plants after the application of these electromagnetic field treatments. The EM field wasproduced using RF transmitter of 2.4 GHz with horn antenna to expose the experiment plants to the maximum in order to get the best possible outcome.

Conclusion

Overall results exhibited that the exposure to electromagnetic field treatment yielded a slightly stressed environment, which affected the cucumber plant growth and especially marigold plants development. Increasing the electromagnetic field yielded to reduce plant length and flowering rate. Higher electrolyte leakage coupled with reduced plant growth may be a function of free radical processes. It has been reported earlier that free radicals are potentially detrimental in disrupting biological systems e. g. membrane (lipid peroxidation), DNA, proteins, damage. Apparently, our preliminary results showed similar mechanism of free radical process a source of abiotic stress factor in plants; however repeated experiments on diverse crops are underway to validate our initial results on marigold. The plants in different light boxes were affected with the heat produced by the LEDs. This factor should be taken seriously in any upcoming work with limited closed space. Also, the Biology or microscopic analysis is recommended to investigate it in more
depth to conclude accordingly. The cucumber seeds inside the boxes did not germinate because of external effects (not related to our system) since even the seeds outside the boxes did not germinate.


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Effects of Mobile Phone Exposure on Mast Cells in Rat Dura Mater
Tumkaya L, Kalkan Y, Gokce FM, Erdivanli B, Yilmaz A, Bahceci I, Yazici ZA, Mercantepe T. The Effects of Mobile Phone Exposure on Mast Cells in Rat Dura Mater. Int J Morphology. 37(2):719-723. Jun 2019.

Abstract
Mobile phone use has increased rapidly. The central nervous system has been shown to be adversely affected by its electromagnetic field (EMF) resulting in headache and sleep disturbances. How the cells make up the CNS and are affected by EMF is unclear. However, because of their central role in inflammation through diverse stimuli including radiation, this study aimed to investigate the effects of electromagnetic fields induced by mobile phones on mast cells in rat dura mater. A total of 18 adult, female, Sprague-Dawley rats were divided into two groups. The choice of female rats for his study was based on recent surveys demonstrating that mobile phone use is more frequent and prolonged among females. The study group was exposed to 900 MHz electromagnetic field (1 h/day for 45 days). In the end of the study, duramater tissue was extracted and stained using Toluidine blue. Mast cells were counted and results were analysed using Student t test. Mean mast cell number was 202.33 +/- 982 and 456.78 +/- 35.01 in the control and study groups, respectively (p<0.05). Analysis of serum electrolyte and immunoglobulin E levels showed no statistically significant difference between the two groups (p>0.05). The study showed that mobile phone exposure increased mast cell number and degranulation in rat dura mater. Further studies arc required to evaluate the clinical implications of these findings.


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Effect of Extremely Low‐Frequency (ELF) Electromagnetic Fields on Musculoskeletal Disorders and Role of Oxidative Stress

Hosseinabadi MB, Khanjani N. The Effect of Extremely Low‐Frequency Electromagnetic Fields on the Prevalence of Musculoskeletal Disorders and the Role of Oxidative Stress. Bioelectromagnetics. Published online June 18, 2019. https://doi.org/10.1002/bem.22198

Abstract

Extremely low‐frequency electromagnetic fields (ELF‐EMFs) may cause negative health effects. This study aimed to investigate the direct and indirect effects of chronic exposure to extremely low‐frequency electric and magnetic fields on the prevalence of musculoskeletal disorders (MSDs).

In this cross‐sectional study, 152 power plant workers were enrolled. The exposure level of employees was measured based on the IEEE Std C95.3.1 standard. Superoxide dismutase (SOD), catalase (Cat), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and malondialdehyde (MDA) (independent variables) were measured in the serum of subjects. The Nordic musculoskeletal questionnaire was used to assess MSDs (dependent variable).

The mean exposure of electric and magnetic fields were 4.09 V/m (standard deviation [SD] = 4.08) and 16.27 µT (SD = 22.99), respectively. Increased levels of SOD, Cat, GPx, and MDA had a direct significant relation with MSDs. In the logistic regression model, SOD (odds ratio [OR] = 0.952, P = 0.026), GPx (OR = 0.991, P = 0.048), and MDA (OR = 0.741, P = 0.021) were significant predictors of MSDs.

ELF‐EMFs were not related to MSDs directly; however, increased levels of oxidative stress may cause MSDs.


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Evidence of plasma membrane-mediated ROS generation upon ELF exposure in neuroblastoma cells

Merla C, Liberti M, Consales C, Denzi A, Apollonio F, Marino C, Benassi B. Evidences of plasma membrane-mediated ROS generation upon ELF exposure in neuroblastoma cells. Biochim Biophys Acta Biomembr. 2019 Jun 11. pii: S0005-2736(19)30137-3. doi: 10.1016/j.bbamem.2019.06.005.

Abstract

BACKGROUND: Molecular mechanisms of interaction between cells and extremely low frequency magnetic fields (ELF-MFs) still represent a matter of scientific debate. In this paper, to identify the possible primary source of oxidative stress induced by ELF-MF in SH-SY5Y human neuroblastoma cells, we estimated the induced electric field and current density at the cell level.

METHODS: We followed a computational multiscale approach, estimating the local electric field and current density from the whole sample down to the single cell level. The procedure takes into account morphological modeling of SH-SY5Y cells, arranged in different topologies. Experimental validation has been carried out: neuroblastoma cells have been treated with Diphenyleneiodonium (DPI) -an inhibitor of the plasma membrane enzyme NADPH oxidase (Nox)- administered 24 h before exposure to 50 Hz (1 mT) MF.

RESULTS: Macroscopic and microscopic dosimetric evaluations suggest that increased current densities are induced at the plasma membrane/extra-cellular medium interface; identifying the plasma membrane as the main site of the ELF-neuroblastoma cell interaction. The in vitro results provide an experimental proof that plasma membrane Nox exerts a key role in the redox imbalance elicited by ELF, as DPI treatment reverts the generation of reactive oxygen species induced by ELF exposure.

GENERAL SIGNIFICANCE: Microscopic current densities induced at the plasma membrane are likely to play an active physical role in eliciting ELF effects related to redox imbalance. Multiscale computational dosimetry, supported by an in vitro approach for validation, is proposed as the innovative and rigorous paradigm to unveil mechanisms underlying the complex ELF-MF interactions.


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Extremely low frequency electromagnetic radiation enhanced energy metabolism and  induced oxidative stress in Caenorhabditis elegans

Sun YY, Wang YH, Li ZH, Shi ZH, Liao YY, Tang C, Cai P. [Extremely low frequency electromagnetic radiation enhanced energy metabolism and induced oxidative stress in Caenorhabditis elegans]. [Article in Chinese] . Sheng Li Xue Bao. 2019 Jun 25;71(3):388-394.

Abstract

The aim of this study was to determine the effects of extremely low frequency electromagnetic field (ELF-EMF) on energy metabolism and oxidative stress in Caenorhabditis elegans (C. elegans). Worms in three adult stages (young adult stage, egg-laying stage and peak egg-laying stage) were investigated under 50 Hz, 3 mT ELF-EMF exposure. ATP levels, ATP synthase activity in vivo, reactive oxygen species (ROS) content, and changes of total antioxidant capacity (TAC) were detected, and worms' oxidative stress responses were also evaluated under ELF-EMF exposure. The results showed that ATP levels were significantly increased under this ELF-EMF exposure, and mitochondrial ATP synthase activity was upregulated simultaneously. In young adult stage, worms' ROS level was significantly elevated, together with upregulated TAC but with a decreased ROS-TAC score indicated by principal component analysis. ROS level and TAC of worms had no significant changes in egg-laying and peak egg-laying stages. Based on these results, we concluded that ELF-EMF can enhance worm energy metabolism and elicit oxidative stress, mainly manifesting as ATP and ROS level elevation together with ATP synthase upregulation and ROS-TAC score decrease in young adult C. elegans.


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Effect of low frequency electromagnetic radiation on the morphology of dental and periodontal tissues

Markovskaya IV. The effect of low frequency electromagnetic radiation on the morphology of dental and periodontal tissues (experimental investigation). Wiad Lek. 2019;72(5 cz 1):773-778.

Abstract

OBJECTIVE: Low intensity electromagnetic effects possess a high biological activity, reduce the adaptive reserves of the body, impair immunity, adversely affect the functional state of the organs and body systems. The aim of the study was to identify in the experiment the effect of low-frequency electromagnetic radiation on the morphological state of the dental and periodontal tissue.

PATIENTS AND METHODS: The experiment was conducted on WAG rats weighing 180-200 g, during which two groups were formed: group 1 (control group) included 12 WAG rats, which were not performed any manipulations; the rats of group 2 (investigation group) (n=12) for 30 days were exposed to a 70 kHz low-frequency alternating electric field (5th frequency range) daily from 9.00 to 12.00. To simulate a low-frequency 70 kHz alternating electric field, certified experimental equipment was used. The study material was the upper jaw tissue. Histological and histochemical staining methods were used. Morphometric study was conducted.

RESULTS: Complex morphological study on the experimental material allowed identifying the damaging effect of low-frequency electromagnetic radiation on the structural components of tooth and periodontal tissues.

CONCLUSION: Our findings suggest that the workers who are exposed to occupational low-frequency electromagnetic radiation should be included in the risk group for developing diseases of the dentomandibular system in order to carry out timely therapeutic and preventive measures.