International Commission On Non-Ionizing Radiation Protection Guidelines Research Articles

Fuzzy Decision Algorithm for Health Impact Assessment in a 5G Environment

The widespread use of mobile phones and other wireless communication devices raises concerns about radiation’s impact on humans. A new algorithm for making decisions for the assessment of the biological impact of non-ionizing radiation is presented in this paper. The algorithm was developed according to ICNIRP (the International Commission on Non-Ionizing Radiation Protection) guidelines using fuzzy logic. Appropriate membership function choices and optimized fuzzy rule selections are crucial for fuzzy modeling. Fuzzy logic is widely applied for multiparameter process modeling using linguistic forms and mathematical expressions. A comprehensive analysis of 4G and 5G network parameters was carried out including electrical and magnetic field strengths, frequency ranges, power densities, and exposure times. The proposed hands-on fuzzy decision-making algorithm can be used for fast, easy, and reliable non-ionizing radiation risk assessment for the following social groups: residents, on-site workers, and professional users.

Aligning Exposure Limits for Contact Currents with Exposure Limits for Electric Fields.

The Institute for Electrical and Electronic Engineers (IEEE) and the International Commission on Non-ionizing Radiation Protection (ICNIRP) have established limits for exposures to electromagnetic fields across the 0-300 GHz (non-ionizing) spectrum, including limits on contact currents ( CC ) specified by IEEE for 0-110 MHz (ICNIRP issued a CC "guidance level"). Both sets of limits seek to protect against potentially adverse effects, including aversive electrostimulation at frequencies <100 kHz and excessive heating of tissue at frequencies >100 kHz. For the most part, CC is linked to electric field ( E -field) exposures for an ungrounded person contacting a grounded object, with the short-circuit current ( I SC ) through the contact point (usually the hand) equivalent to the current through the grounded feet of a free-standing person exposed to a vertically polarized E -field. The physical linkage between these two quantities dictates that their respective exposure limits align with one another, which is presently not the case, especially with respect to frequencies from100 kHz to 110 MHz. Here we focus specifically on recommendations for revisions to the IEEE standard, IEEE Std C95.1™-2019 ("IEEE C95.1"), in which the E -field exposure limit ( E -field exposure reference levels, ERL s) >100 kHz induces substantially greater currents than the CC ERL s currently prescribed. The most important scenario deserving of attention concerns finger contact through a 1-cm 2 cross-sectional interface between the skin and a grounded conductor in which the rate of temperature rise in the presence of an E -field ERL can be rapid enough to cause a burn injury. This rate is highly dependent on the moistness/dryness of the skin at the contact point (i.e., its impedance)-a highly variable value-with temperature increasing more rapidly with increasing dryness (greater contact impedance). The two main remedies to alleviate the possibility of injury in this "touch" scenario are to (a) limit the time of finger contact to 1 s in all cases and (b) revise the E -field ERL between 100 kHz and 30 MHz from a "hockey-stick-shaped" curve vs. frequency to a "ramp" across this frequency range. These measures factored in with the real-world prevalence of potentially hazardous scenarios should afford greater protection against adverse outcomes than is presently the case. IEEE C95.1 also specifies limits for grasp contact (15 cm 2 in the palm) and associated wrist heating, plus heating in the ankles from free-standing induction. However, these scenarios are more manageable compared to finger touch due mainly to the comparatively lower rates of tissue heating attributable to the wrist's and ankle's relatively greater cross-sectional area. Recommendations for grasp can thus be dealt with separately. Two identified but unaddressed issues in IEEE C95.1 deserving of further attention are first, the circumstance in which a grounded person contacts an ungrounded object situated in an electric field for which there are countless numbers of scenarios that are not amenable to a single ERL . Second, arcing between an extended limb and E -field-exposed object is perhaps the most hazardous of all scenarios. Both of these scenarios cannot be stereotyped and must be dealt with on a case-by-case basis. Future revisions of IEEE Std C95.1-2019 (and the ICNIRP guidelines) will benefit from improved insight into strategies of affording protection from potentially adverse effects in these circumstances.

Derivation of maximum permissive switching time for automatic welding filter based on retinal thermal and blue light exposure limits

Automatic welding filters are intended to protect the eyes of the welder from optical radiation generated by the welding process. Safety standards for automatic welding filters (AWFs) have been developed worldwide. However, switching time requirements have not been studied considering the exposure limits established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) or the American Conference of Governmental Industrial Hygienists (ACGIH). The aim of this study is to derive the maximum permissive switching time based on ICNIRP guidelines for exposure to intense optical radiation. The single and cumulative exposures associated with retinal thermal and blue light hazards were assessed in the welding environment. The results show that the maximum switching time is inversely proportional to the exponential function of the shade number difference. The proposed maximum switching time, 1/2 to 1/10 smaller than the current ISO, is derived from the effective blue light radiance limits. In addition, an evaluation of the periodic short circuit welding indicates that AWFs do not transmit hazardous levels of radiation in the dark state.

Protection of Workers Exposed to Radiofrequency Electromagnetic Fields: A Perspective on Open Questions in the Context of the New ICNIRP 2020 Guidelines

Workers in occupational settings are usually exposed to numerous sources of electromagnetic fields (EMF) and to different physical agents. Risk assessment for industrial workplaces concerning EMF is not only relevant to operators of devices or machinery emitting EMF, but also to support-workers, bystanders, service and maintenance personnel, and even visitors. Radiofrequency EMF guidelines published in 2020 by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) may also be indirectly applied to assess risks emerging from EMF sources at workplaces by technical standards or legislation. To review the applicability and adequacy to assess exposure to EMF in occupational settings in the European Union, the most current ICNIRP guidelines on radiofrequency EMF are reviewed. Relevant ICNIRP fundamentals and principles are introduced, followed by practical aspects of exposure assessment. To conclude, open questions are formulated pointing out gaps between the guidelines' principles and occupational practice, such as the impact of hot and humid environments and physical activity or controversies around ICNIRPS's reduction factors in view of assessment uncertainty in general. Thus, the article aims to provide scientific policy advisors, labor inspectors, or experts developing standards with a profound understanding about ICNIRP guidelines' applicability to assess hazards related to radiofrequency EMF in occupational settings.

What evidence exists on the impact of anthropogenic radiofrequency electromagnetic fields on animals and plants in the environment? A systematic map protocol

BackgroundExposure to radiofrequency (RF) electromagnetic fields (EMF), particularly from telecommunications sources, is one of the most common and fastest growing anthropogenic factors on the environment. In many countries, humans are protected from excessive RF EMF exposure by safety standards that are based on guidelines by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The ICNIRP guidelines are based on knowledge of how RF EMF affects the human body, however, there are currently no recognised international guidelines to specifically protect animals and plants. Whether the ICNIRP guidelines for humans is adequate to provide protection to the environment is a subject of active debate. This systematic map will collate all the available evidence on whether anthropogenic RF EMF has a negative effect on plants and animals in the environment. The map will also identify gaps in knowledge, recommend future research and inform environmental and radiation protection authorities.MethodsThe proposed systematic map will include peer-reviewed and grey literature published in English. The EMF—Portal, PubMed and Web of Science databases will be searched using a search string prepared by the review team and tested for comprehensiveness against a list of known relevant reviews. Once duplicates are removed, retrieved articles will be screened in three stages: title, abstract, and full text. Studies will be selected with a subject population of all plants and animals, with exposures to anthropogenic RF EMF (frequency range 100 kHz–300 GHz) compared to no or lower-level exposure, and for all outcomes related to the studied populations. Kappa statistic tests will be conducted at each stage to ensure consistency of decision-making regarding the predefined inclusion/exclusion criteria. Eligible studies will then proceed to the data extraction phase, which will extract meta-data such as bibliographic information, taxonomic information, RF EMF exposure data, outcome(s), sample size, etc. The extracted data will then be organised into a systematic map and the findings summarised by cross-tabulating key meta-data variables in heat maps, charts or other data visualization methods. The systematic map will identify gaps in knowledge, priorities for future research and potential subtopics for further analysis and/or systematic review.

Assessment of radiofrequency radiation exposure level from selected base transceiver stations in Ogbomoso, Oyo State, Nigeria

With the growth of mobile phone technology globally, which has also influenced the number of mobile phone masts, the effects of radiofrequency radiation (RFR) have been a major concern of scientist globally. Many literatures have described the effects on the human health and his environment. We embarked on this study to assess the power densities of RFR from base transceiver stations (BTS) in Ogbomoso, Oyo State. Electrosmog meter was used, the power densities of RFR were taken from 12 BTS across 4 Local Governments in Ogbomoso at different distances. The power densities were measured to evaluate the mean power densities across Ogbomoso and its environment with the standard values provided by International Commission on Non-Ionizing Radiation Protection (ICNIRP). The maximum average 718.6 μW/m2 was observed at 25 m away from the mast, which is below the ICNIRP guidelines. The results showed that the radiation level in the Local Governments is below the ICNIRP limit. Hence, we recommend that individuals should keep their exposure as low as reasonably achievable.

Assessment of Possible Health Risks Potential of Electromagnetic Fields from High Voltage Power Transmission Lines in Akure, Nigeria

The primary objective of this paper is to assess and predict the health risk potential of extremely low-frequency electromagnetic fields (ELF-EMFs) emitted from high voltage power transmission lines (HVPTLs) in Akure metropolis, Nigeria. The assessment was conducted using BENETECH GM3120 Electromagnetic Radiation Tester to measure both the electric field strength and magnetic flux density emitted from 33 kV, 132 kV, 132/330 kV and 330 kV power transmission lines within the metropolis. The data collected were analysed and compared with limiting tolerable values by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for both occupational and the general public. The comparative result shows that the maximum measured electric field strength and magnetic flux density in this study are lower than 40% of the limiting tolerable values in ICNIRP guidelines. Thus, the result of this study has shown clearly that the emitted ELF-EMFs from HVPTLs is not strong enough to cause any adverse effect health on human. In addition, analysis of the measured data also shows that the emitted ELF-EMFs from the HVPTLs vanish completely at about 60 m radius from the transmission lines, which implies that 60 m radius from transmission lines is an ideal experimental shortest possible distance residential building and people should be from HVPTLs in order to reduce the exposure level of people to EMFs radiations from HVPTLs.

Assessment of Electromagnetic Pollution in Some Hospitals and Schools in Al-Najaf City

The tremendous benefits of using cellular phones, which began to increase and unprecedented spread worldwide last decade, were accompanied by harmful effects on the environment due to the increase in electromagnetic radiation (EMR) which be emitted from mobile phone towers. This effect on humans, animals, and plants, which is considered a form of environmental pollution, was sensed by developed countries and Environmental protection organizations. These countries have established restrictions and enacted laws to reduce their negative impact on living beings. The field survey included six major hospitals and 38 schools were distributed over the central neighbourhoods in Al-Najaf city. The results showed that power density (PD) measurements for 4 out of 6 hospitals and 27 out of 38 schools were higher than the biological limit (BL) adopted in this article. This limit is considered as an indicator of the onset of a harmful effect on brain and body tissues. The highest value for PD in hospitals was 5.62 mW/m2 recorded in Al-Sadr Teaching Hospital. PD measurements ranged from1.33 from 3.92 mW/m2 in the selected schools where its readings exceeded the BL. When comparing the PD measurements at the selected sites with limits set by the "International Commission on Non-Ionizing Radiation Protection (ICNIRP)" they were less than the recommended limit in those specifications. All values of specific absorption rates (SAR) in W/Kg were below the ICNIRP Guidelines' limit. However, they were above the biological limit for four hospitals and several of the selected schools.

Aspects on the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2020 Guidelines on Radiofrequency Radiation

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) published 2020 updated guidelines on radiofrequency (RF) radiation in the frequency range 100 kHz to 300 GHz. Harmful effects on human health and the environment at levels below the guidelines are downplayed although evidence is steadily increasing. Only thermal (heating) effects are acknowledged and therefore form the basis for the guidelines. Despite the increasing scientific evidence of non-thermal effects, the new ICNIRP guidelines are not lower compared with the previous levels. Expert groups from the WHO, the EU Commission and Sweden are to a large extent made up of members from ICNIRP, with no representative from the many scientists who are critical of the ICNIRP standpoint.

Comments on the 2013 ICNIRP Laser Guidelines.

Comments on the 2013 ICNIRP Laser Guidelines.

Safe exposure distances for transcranial magnetic stimulation based on computer simulations

The results of a computer simulation examining the compliance of a given transcranial magnetic stimulation device to the 2010 International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines are presented. The objective was to update the safe distance estimates with the most current safety guidelines, as well as comparing these to values reported in previous publications. The 3D data generated was compared against results available in the literature, regarding the MCB-70 coil by Medtronic. Regarding occupational exposure, safe distances of 1.46 m and 0.96 m are derived from the simulation according to the 2003 and 2010 ICNIRP guidelines, respectively. These values are then compared to safe distances previously reported in other studies.

Electrical exposure analysis of galvanic-coupled intra-body communication based on the empirical arm models

BackgroundIntra-body communication (IBC) is one of the highlights in studies of body area networks. The existing IBC studies mainly focus on human channel characteristics of the physical layer, transceiver design for the application, and the protocol design for the networks. However, there are few safety analysis studies of the IBC electrical signals, especially for the galvanic-coupled type. Besides, the human channel model used in most of the studies is just a multi-layer homocentric cylinder model, which cannot accurately approximate the real human tissue layer.MethodsIn this paper, the empirical arm models were established based on the geometrical information of six subjects. The thickness of each tissue layer and the anisotropy of muscle were also taken into account. Considering the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines, the restrictions taken as the evaluation criteria were the electric field intensity lower than 1.35 × 104f V/m and the specific absorption rate (SAR) lower than 4 W/kg. The physiological electrode LT-1 was adopted in experiments whose size was 4 × 4 cm and the distance between each center of adjoining electrodes was 6 cm. The electric field intensity and localized SAR were all computed by the finite element method (FEM). The electric field intensity was set as average value of all tissues, while SAR was averaged over 10 g contiguous tissue. The computed data were compared with the 2010 ICNIRP guidelines restrictions in order to address the exposure restrictions of galvanic-coupled IBC electrical signals injected into the body with different amplitudes and frequencies.ResultsThe input alternating signal was 1 mA current or 1 V voltage with the frequency range from 10 kHz to 1 MHz. When the subject was stimulated by a 1 mA alternating current, the average electric field intensity of all subjects exceeded restrictions when the frequency was lower than 20 kHz. The maximum difference among six subjects was 1.06 V/m at 10 kHz, and the minimum difference was 0.025 V/m at 400 kHz. While the excitation signal was a 1 V alternating voltage, the electric field intensity fell within the exposure restrictions gradually as the frequency increased beyond 50 kHz. The maximum difference among the six subjects was 2.55 V/m at 20 kHz, and the minimum difference was 0.54 V/m at 1 MHz. In addition, differences between the maximum and the minimum values at each frequency also decreased gradually with the frequency increased in both situations of alternating current and voltage. When SAR was introduced as the criteria, none of the subjects exceeded the restrictions with current injected. However, subjects 2, 4, and 6 did not satisfy the restrictions with voltage applied when the signal amplitude was ≥ 3, 6, and 10 V, respectively. The SAR differences for subjects with different frequencies were 0.062–1.3 W/kg of current input, and 0.648–6.096 W/kg of voltage input.ConclusionBased on the empirical arm models established in this paper, we came to conclusion that the frequency of 100–300 kHz which belong to LF (30–300 kHz) according to the ICNIRP guidelines can be considered as the frequency restrictions of the galvanic-coupled IBC signal. This provided more choices for both intensities of current and voltage signals as well. On the other hand, it also makes great convenience for the design of transceiver hardware and artificial intelligence application. With the frequency restrictions settled, the intensity restrictions that the current signal of 1–10 mA and the voltage signal of 1–2 V were accessible. Particularly, in practical application we recommended the use of the current signals for its broad application and lower impact on the human tissue. In addition, it is noteworthy that the coupling structure design of the electrode interface should attract attention.

Measurement and analysis of power-frequency magnetic fields in residences: Results from a pilot study

AimExtremely low-frequency magnetic fields (ELF-MFs) are emitted by electrical household appliances, wiring, meter boxes, conductive plumbing, power lines and transformers. Some of the studies investigating the link between ELF-MFs and health problems have not adequately characterized the magnetic field exposure of subjects, as they did not always measure residential magnetic fields or measure in locations where residents are most exposed. Considering this, there is a need for good quality assessments of residential ELF-MFs in different geographical regions to collect general public exposure data and to identify high sources of magnetic fields. Such studies have the potential to add significant scientific knowledge about residential exposure and appropriate precautions to reduce exposure, improve the quality of life and substantially reduce health care costs. Subject and methodsIn this work, we analyzed the ELF-MFs from 3163 datasets collected from 100 houses in Australia. Measurements were carried out in different geographical locations and were assessed for compliance with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) Guidelines. Then we compared our measurements with another twenty-three peer-reviewed studies, published 1987–2015, reporting magnetic field measurements in residences. ResultsThe observed average (geometric mean) magnetic field values were; bed 0.85, bedroom 1.39 mG, baby cot 0.39 mG, children’s play area 0.47 mG, and family room 0.30 mG. Our results show considerable variation in the fields to which residents are typically exposed, particularly in beds (21.83%) and bedrooms (33.33%) where the percentage of measurements greater than 4 mG was considerable. Some emissions exceeded the general public exposure levels of the ICNIRP Guidelines, with the potential for residents to be exposed above these levels. However, away from electrical appliances, the average field in all rooms was 0.30–1.39 mG. We show that simple precautions can be applied to reduce exposure to ELF-MFs in residences and thereby minimize potential risks to health and wellbeing. ConclusionOur investigation provides a new data collection model for future surveys, which could be conducted with larger samples to verify our observations. Additionally, this data could be useful as a reference for researchers and those members of the general public who do not have access to the necessary measuring equipment.

Relationship of External Field Strength With Local and Whole-Body Averaged Specific Absorption Rates in Anatomical Human Models

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines and the IEEE C95.1 standard are currently under revision. In the guidelines/standard, the dominant effect for electromagnetic field exposures at frequencies above 100 kHz is the thermal effect. The whole-body-and 10g-averaged specific absorption rates (SARs), which are surrogates for core and local temperature elevations, respectively, are set as metrics for exposure evaluation. The external field strengths or incident power density, corresponding to the limit for SARs, are also used as metrics for practical compliance purposes. Although the limits for the SARs are identical amongst the guidelines/standard, the limits for the external field strengths differ by a factor of 7.4–12.9 in an intermediate frequency range (100 kHz–100 MHz). Due to the fact that the standard/guidelines were published before the computation with anatomical human models was available, it is worth revisiting the relationship between the SARs and external field strengths by computations using the human models. Intercomparison using different numerical codes was also performed to verify the results. For the main finding, as expected, the 10g-averaged SAR was a less restrictive factor for whole-body exposure over the frequencies considered in this paper. It was also found that the relationship between SARs and external field strength was satisfied, but was more conservative in the ICNIRP guidelines, whereas there were slight discrepancies below 30 MHz in the IEEE standard. The computational results would be useful for revising the permissible external field strength based on scientific results.

A History of the International Commission on Non-Ionizing Radiation Protection

Concern about health risks from exposure to non-ionizing radiation (NIR) commenced in the 1950s after tracking radars were first introduced during the Second World War. Soon after, research on possible biological effects of microwave radiation in the former Soviet Union and the U.S. led to public and worker exposure limits being much lower in Eastern European than in Western countries, mainly because of different protection philosophies. As public concern increased, national authorities began introducing legislation to limit NIR exposures from domestic microwave ovens and workplace devices such as visual display units. The International Radiation Protection Association (IRPA) was formed in 1966 to represent national radiation protection societies. To address NIR protection issues, IRPA established a Working Group in 1974, then a Study Group in 1975, and finally the International NIR Committee (INIRC) in 1977. INIRC's publications quickly became accepted worldwide, and it was logical that it should become an independent commission. IRPA finally established the International Commission on Non-Ionizing Radiation Protection (ICNIRP), chartering its remit in 1992, and defining NIR as electromagnetic radiation (ultraviolet, visible, infrared), electromagnetic waves and fields, and infra- and ultrasound. ICNIRP's guidelines have been incorporated into legislation or adopted as standards in many countries. While ICNIRP has been subjected to criticism and close scrutiny by the public, media, and activists, it has continued to issue well-received, independent, science-based protection advice. This paper summarizes events leading to the formation of ICNIRP, its key activities up to 2017, ICNIRP's 25th anniversary year, and its future challenges.

High radiofrequency radiation at Stockholm Old Town: An exposimeter study including the Royal Castle, Supreme Court, three major squares and the Swedish Parliament.

Exposure to radiofrequency (RF) radiation was classified as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer at WHO in 2011. The exposure pattern is changing due to the rapid development of technology. Outdoor RF radiation level was measured during five tours in Stockholm Old Town in April, 2016 using the EME Spy 200 exposimeter with 20 predefined frequencies. The results were based on 10,437 samples in total. The mean level of the total RF radiation was 4,293 µW/m2 (0.4293 µW/cm2). The highest mean levels were obtained for global system for mobile communications (GSM) + universal mobile telecommunications system (UMTS) 900 downlink and long-term evolution (LTE) 2600 downlink (1,558 and 1,265 µW/m2, respectively). The town squares displayed highest total mean levels, with the example of Järntorget square with 24,277 µW/m2 (min 257, max 173,302 µW/m2). These results were in large contrast to areas with lowest total exposure, such as the Supreme Court, with a mean level of 404 µW/m2 (min 20.4, max 4,088 µW/m2). In addition, measurements in the streets surrounding the Royal Castle were lower than the total for the Old Town, with a mean of 756 µW/m2 (min 0.3, max 50,967 µW/m2). The BioInitiative 2012 Report defined the scientific benchmark for possible health risks as 30–60 µW/m2. Our results of outdoor RF radiation exposure at Stockholm Old Town are significantly above that level. The mean exposure level at Järntorget square was 405-fold higher than 60 µW/m2. Our results were below the reference level on 10,000,000 µW/m2 established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), which, however, are less credible, as they do not take non-thermal effects into consideration and are not based on sound scientific evaluation. Our highest measured mean level at Järntorget was 0.24% of the ICNIRP level. A number of studies have found adverse, non-thermal (no measurable temperature increase) health effects far below the ICNIRP guidelines.

Assessment of General Public Exposure to LTE signals compared to other Cellular Networks Present in Thessaloniki, Greece.

To assess general public exposure to electromagnetic fields from Long Term Evolution (LTE) base stations, measurements at 10 sites in Thessaloniki, Greece were performed. Results are compared with other mobile cellular networks currently in use. All exposure values satisfy the guidelines for general public exposure of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), as well as the reference levels by the Greek legislation at all sites. LTE electric field measurements were recorded up to 0.645 V/m. By applying the ICNIRP guidelines, the exposure ratio for all LTE signals is between 2.9 × 10-5 and 2.8 × 10-2. From the measurements results it is concluded that the average and maximum power density contribution of LTE downlink signals to the overall cellular networks signals are 7.8% and 36.7%, respectively.

Endonuclease G is Upregulated and Required in Testicular Germ Cell Apoptosis after Exposure to 60 Hz at 200 μT

Several reports supported that continuous exposure to 60 Hz magnetic field (MF) induces testicular germ cell apoptosis in vivo. We recently evaluated duration- and dose-dependent effects of continuous exposure to a 60 Hz MF on the testes in mice. BALB/c male mice were exposed to a 60 Hz MF at <TEX>$100{\mu}T$</TEX> for 24 hours a day for 2, 4, 6, or 8 weeks, and at 2, 20 or <TEX>$200{\mu}T$</TEX> for 24 hours a day for 8 weeks. To induce the apoptosis of testicular germ cell in mice, the minimum dose is <TEX>$20{\mu}T$</TEX> at continuous exposure to a 60 Hz MF for 8 weeks, and the minimum duration is 6 weeks at continuous exposure of <TEX>$100{\mu}T$</TEX>. Continuous exposure to a 60 Hz MF might affect duration- and dose-dependent biological processes including apoptotic cell death and spermatogenesis in the male reproductive system of mice. The safety guideline of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) indicates that the permissible maximum magnetic flux density for general public exposure is <TEX>$200{\mu}T$</TEX> at 60 Hz EMF (ICNIRP Guidelines, 2010). In the present study, we aimed to examine the expression of pro- and anti-apoptotic genes regulated by the continuous exposure to 60 Hz at <TEX>$200{\mu}T$</TEX> in Sprague-Dawley rats for 20 weeks. The continuous exposure to 60 Hz at <TEX>$200{\mu}T$</TEX> does not affect the body and testicular weight in rats. However, exposure to 60 Hz MF significantly affects testicular germ cell apoptosis and sperm count. Further, the apoptosis-related gene was scrutinized after exposure to 60 Hz at <TEX>$200{\mu}T$</TEX> for 20 weeks. We found that the message level of endonuclease G (EndoG) was greatly increased following the exposure to 60 Hz at <TEX>$200{\mu}T$</TEX> compared with sham control. These data suggested that 60 Hz magnetic field induced testicular germ cell apoptosis through mitochondrial protein Endo G.

In vitro evaluation of genotoxic effects under magnetic resonant coupling wireless power transfer.

Wireless power transfer (WPT) technology using the resonant coupling phenomenon has been widely studied, but there are very few studies concerning the possible relationship between WPT exposure and human health. In this study, we investigated whether exposure to magnetic resonant coupling WPT has genotoxic effects on WI38VA13 subcloned 2RA human fibroblast cells. WPT exposure was performed using a helical coil-based exposure system designed to transfer power with 85.4% efficiency at a 12.5-MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The specific absorption rate at the positions of the cell culture dishes matches the respective reference levels stated in the ICNIRP guidelines. For assessment of genotoxicity, we studied cell growth, cell cycle distribution, DNA strand breaks using the comet assay, micronucleus formation, and hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene mutation, and did not detect any significant effects between the WPT-exposed cells and control cells. Our results suggest that WPT exposure under the conditions of the ICNIRP guidelines does not cause detectable cellular genotoxicity.

In vitro exposure system using magnetic resonant coupling wireless power transfer

Wireless power transfer (WPT) technology using the resonant coupling phenomenon has been widely studied. However, possible relationships between WPT exposure and human health have not been experimentally evaluated. In this study, we developed a new in vitro exposure system to evaluate the biological effects of magnetic resonant coupling WPT. The WPT was carried out using a self-resonant helical coil, which was designed to transfer the power with 85.4% efficiency at a 12.5 MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The specific absorption rate (SAR) at the positions of the cell culture dishes match the respective reference levels stated in the ICNIRP guidelines. In this paper, the coil design for the magnetic resonant coupling in the in vitro exposure system and characteristics, such as power transfer efficiency, electric field and magnetic field distributions, and SAR of the exposure system, are described.