Non-Ionizing Radiation Protection Research Articles

Power Density Measurement within Kaduna North Area of Kaduna State, Nigeria

The measurement of possible presence of radiofrequency (RF) radiations from telecommunication base stations was carried out within Kaduna North Area of Kaduna State, to estimate the maximum level of power density from RF radiations to which the member of the populace within specific radius from the base transceiver station (BTS) are exposed to in relation to the existing guidelines to human exposure. Power density S (µWm-2) measurements were made at interval of 20 m to check the exposure level at public locations from 10 RF antenna sites starting from the foot of each BS to distance (radius) of 100 m using Aaronia Spectran HF-4060 Analyser and the electric field strength E (Vm-1) were calculated. The highest and lowest value obtained from measured mean power densities were 108.27 µWm-2 and 94.74 µWm-2 from a distance of 100 m and 40 m respectively. Also, the highest and lowest average electric field strength were 202.03 (Vm-1) and 188.99 (Vm-1) at 100 m and 40 m respectively. The result obtained, indicates that the measured values were far less than the permissible exposure limits for both workers and the general public as set by the International Commission on Non-ionizing Radiation Protection (ICNIRP). These results shows that the exposure levels in these areas are low and as such will not pose significant health risks to the people living in the study area.

Towards real-time magnetic dosimetry simulations for inductive charging systems

PurposeInductive charging systems for electrically powered cars produce a magneto-quasistatic field and organism in the vicinity might be exposed to that field. Magneto-quasistatic fields induce electric fields in the human body that should not exceed limits given by the International Commission of Non-Ionizing Radiation protection (ICNIRP) to ensure that no harm is done to the human body. As these electric fields cannot be measured directly, they need to be derived from the measured magnetic flux densities. To get an almost real-time estimation of the harmfulness of the magnetic flux density to the human body, the electric field needs to be calculated within a minimal computing time. The purpose of this study is to identify fast linear equations solver for the discrete Poisson system of the Co-Simulation Scalar Potential Finite Difference scheme on different graphics processing unit systems.Design/methodology/approachThe determination of the exposure requires a fast linear equations solver for the discrete Poisson system of the Co-Simulation Scalar Potential Finite Difference (Co-Sim. SPFD) scheme. Here, the use of the AmgX library on NVIDIA GPUs is presented for this task.FindingsUsing the AmgX library enables solving the equation system resulting from an ICNIRP recommended human voxel model resolution of 2 mm in less than 0.5 s on a single NVIDIA Tesla V100 GPU.Originality/valueThis work is one essential advancement to determine the exposure of humans from wireless charging system in near real-time from in situ magnetic flux density measurements.

Editorial: Introduction to the Special Issue on Progress in Environmental Electromagnetic Safety and Biomedical EMC

The papers in this special issue collects scientific contributions in the field of progress in environmental electromagnetic safety and biomedical EMC. With the advancement of various electronic systems, humans are exposed to electromagnetic emissions. For human exposure from electronic systems, computational or experimental assessment should be conducted to comply with international guidelines for human safety from electromagnetic fields. One of the indispensableEMCchallenges is to ensure safety, protection, and performance under the presence of human body. In wireless systems, the fifth-generation wireless communications (5G),wireless power transfer (WPT), and several related topics lead to new challenges for EMC concerns. The electric and hybrid vehicles often require large currents to support the vehicle operation and can lead to induced electromagnetic field inside passengers. For healthcare and medicine, such as magnetic resonance imaging (MRI) and electrical stimulations, electromagnetic signals are applied on humans. New exposure standards have been published in 2019 from IEEE International Committee on Electromagnetic Safety (0–300 GHz) and in 2020 from International Commission on Non-Ionizing Radiation Protection. For product safety, IECand IEEE are responsible for compliance assessment. To develop further scientific basis for exposure standard, as well as product safety assessment method, further improvement of computational and experimental methods, including dielectric properties measurement and human modeling, are important.

Diurnal variation of RF power density with distance from selected mobile phone base transceiver stations in Offa metropolis, Kwara State Nigeria

Diumal variation of radiofrequency power density with distance from some 20 twenty (20) selected mobile phone base transceiver stations of four (4) major mobile phone network providers (MTN, GLO, 9Mobile, and Airtel) in the Offa metropolis Kwara State Nigeria were studied. A digital Radio-frequency (RF) meter (HF-B8G High Frequency10 Mhz - 8 GHz RF EMF Meter) is used to measure RF field strength first at foot at the base station and subsequently at every interval of 25 m up to 250 m in radial routes. Concurrently, the distance, geographical coordinates, and altitude of each point were measured using a Global Positioning System (GPS). The average maximum power density obtained ranged from 0.294 Wm−2 and 0.057 Wm−2 at a radial distance of 150 m and 0 m away from the base transceiver station respectively. The result of the study shows that the degree of power density variation with distance during the morning, afternoon, and night hours of the day was found to be highly different. The maximum level of exposure to RF electromagnetic radiation was experienced at night, followed by noon, and the minimum in the morning hours of the day in the majority of the base transceiver stations. For the different time of the day considered in this study, the results show that the power density obtained constitute no RF exposure hazard to the dwellers of Offa metropolis when compared with the RF exposure limit prescribed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).

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.

무선 주파수 전자기장 인체영향 연구 현안

This study describes the basis of the International Commission on Non-Ionizing Radiation Protection guidelines and IEEE standards for protecting the human body from exposure to electromagnetic fields (EMF) in the radio frequency band. A brief summary of epidemiological studies that have been conducted on the health risks of long-term EMF exposure in the mobile communication frequency range are reviewed. EMF exposure assessment for epidemiological studies should incorporate mobile-device usage patterns, mobile communication uplink and downlin\k exposure analysis in real environments, age-specific human model development, and dosimetry. Trends and limitations on these topics are described.

Mapping of electric field intensity distribution in the 27 MHz - 3000 MHz frequency range in Diyarbakir city center

It is evident that the rapid development in science and technology has enabled various electronic devices and communication systems. However, there are also undesired effects of those devices on human health. One of those effects is the electromagnetic fields that exceeds the limits. Therefore, the electromagnetic fields emitted by the devices should not exceed a certain level. In that respect, different institutions around the world have determined the certain limits. One of the most important of these organizations in the world is the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Similar to the other existing organizations, the Information and Communication Technologies Authority (BTK) is the responsible authority in Turkey. In this study, electric field intensity values were measured using the drive test method with the Selective Radiation Meter (SRM-3006) device on the main streets in Diyarbakır City Center. Obtained measurement values were shown on dot thematic maps, two-dimensional maps and three-dimensional maps. As a result, locations with the highest electric field intensity were determined by these maps. In addition, the obtained results were compared with the limit values determined by ICNIRP and BTK and it was seen that the measured electric field intensity values did not exceed the exposure limits.

Mapping of electric field intensity distribution in the 27 MHz - 3000 MHz frequency range in Diyarbakir city center

It is evident that the rapid development in science and technology has enabled various electronic devices and communication systems. However, there are also undesired effects of those devices on human health. One of those effects is the electromagnetic fields that exceeds the limits. Therefore, the electromagnetic fields emitted by the devices should not exceed a certain level. In that respect, different institutions around the world have determined the certain limits. One of the most important of these organizations in the world is the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Similar to the other existing organizations, the Information and Communication Technologies Authority (BTK) is the responsible authority in Turkey. In this study, electric field intensity values were measured using the drive test method with the Selective Radiation Meter (SRM-3006) device on the main streets in Diyarbakır City Center. Obtained measurement values were shown on dot thematic maps, two-dimensional maps and three-dimensional maps. As a result, locations with the highest electric field intensity were determined by these maps. In addition, the obtained results were compared with the limit values determined by ICNIRP and BTK and it was seen that the measured electric field intensity values did not exceed the exposure limits.

Tracking Devices for Pets: Health Risk Assessment for Exposure to Radiofrequency Electromagnetic Fields.

Simple SummaryTo increase the probability of reunions occurring between owners and lost pets, tracking devices are applied to pets. The pet’s position is determined by satellites (e.g., GPS) and transmitted by radio frequencies (RFs) to a mobile phone. In this study, the health risks from exposure to radio frequencies emitted by radios, TVs, mobile networks, indoor devices (e.g., WLAN, Bluetooth), mobile phones, and in the use of such tracking devices were investigated. The radiation exposure was found to be well below international limit values, which means that adverse health effects are unlikely to occur. The risk of high exposure of pets is mainly caused by indoor RF-emitting devices, such as WLAN devices. This exposure can be limited through a reduction in the exposure time and an increase in the distance between the animal and the RF-emitting device. Even though the exposure of pets to total radiofrequency electromagnetic field (RF-EMF) levels was found to be below the limit values—and, therefore, not a health risk—recommendations are given for the use of tracking devices and to limit the exposure to indoor devices.Every year, approximately 3% of cats and dogs are lost. In addition to passive methods for identifying pets, radiofrequency tracking devices (TDs) are available. These TDs can track a pet’s geographic position, which is transmitted by radio frequencies. The health risk to the animals from continuous exposure to radiofrequency electromagnetic fields (RF-EMFs) was reviewed. Fourteen out of twenty-one commercially available TDs use 2G, 3G, or 4G mobile networks, and the others work with public frequencies, WLAN, Bluetooth, etc. The exposure of pets to RF-EMFs was assessed, including ambient exposure (radios, TVs, and base stations of mobile networks), exposure from indoor devices (DECT, WLAN, Bluetooth, etc.), and the exposure from TDs. The exposure levels of the three areas were found to be distinctly below the International Commission on Non-Ionising Radiation Protection (ICNIRP) reference levels, which assure far-reaching protection from adverse health effects. The highest uncertainty regarding the exposure of pets was related to that caused by indoor RF-emitting devices using WLAN and DECT. This exposure can be limited considerably through a reduction in the exposure time and an increase in the distance between the animal and the RF-emitting device. Even though the total RF-EMF exposure level experienced by pets was found to be below the reference limits, recommendations were derived to reduce potential risks from exposure to TDs and indoor devices.

Assessing the Health Risk Due to Exposure to Non-ionizing Radiation in the Form of Magnetic Field from Electrical Power Lines

We are all exposed to electromagnetic fields from electrical appliances, electric power transmission lines, distribution lines and power substations. This study was focused on investigating the possible risks to human health due to exposure to extremely low frequency varying magnetic fields from 330 kV, 132 kV, 33 kV and 11kV power lines in southeastern Nigeria. To determine the risks, a magnetic field meter was used to take measurements of magnetic flux from these power lines. From which, the induced current density due to exposure to varying magnetic fields was obtained using a model of the human body known as the prolate spheroid model. The maximum mean magnetic field and current density induced as obtained from the study were 4.790 µT and 0.04214 mA/m², which were obtained from the 330 kV power line. The study results are well below the reference levels of the International Commission for Non-Ionizing Radiation Protection, which are used for comparison, indicating that there is very low exposure risk to people living near these electric power transmission lines.

Профилактические меры по снижению негативного воздействия электромагнитного излучения на здоровье

Man-made electromagnetic waves are the most widely and rapidly expanding exposure in today's world, including exposure in several frequency groups: extremely low frequencies (ELF) from electricity lines, hybrid car batteries and high power lines (>3 Hz–3 kHz), radiofrequency (RF) and microwave frequencies including millimeter waves (3 kHz–300 GHz) from mobile phones, towers, base stations and wireless devices, and intermediate frequencies "Dirty Electricity" emitted from power lines. While such organizations as ICNIRP (the International Commission on Non-Ionizing Radiation Protection) still continue to claim that electromagnetic radiation can cause "only thermal effects", clinging to theory that does not match facts and upholding obsolete thermal safety standards, extensive scientific evidence has clearly demonstrated that non-thermal health effects produced by electromagnetic radiation do exist, are important to health, and should be taken into consideration when safety standards are set. This review aims to highlight some evidence of biologic effects in various body systems, and to suggest preventive measures to reduce such effects on health. Exposure to electromagnetic radiation at intensities lower than thermal safety standards has been associated with non-thermal biological effects including damage and changes to cells and DNA. This review presents evidence of such effects demonstrated in: the hematologic system, the nervous system, the immune system, the reproductive system, the skin and muscles, the cardiovascular system, glucose metabolism, and Electrohypersensitivity ("Microwave sickness"). Protective measures are then suggested to reduce these effects.

Preventive measures to reduce harmful effects produced by electromagnetic radiation on health

Man-made electromagnetic waves are the most widely and rapidly expanding exposure in today's world, including ex- posure in several frequency groups: extremely low frequencies (ELF) from electricity lines, hybrid car batteries and high power lines (>3 Hz–3 kHz), radiofrequency (RF) and microwave frequencies including millimeter waves (3 kHz–300 GHz) from mobile phones, towers, base stations and wireless devices, and intermediate frequencies "Dirty Electricity" emitted from power lines. While such organizations as ICNIRP (the International Commission on Non-Ionizing Radiation Protection) still con- tinue to claim that electromagnetic radiation can cause "only thermal effects", clinging to theory that does not match facts and upholding obsolete thermal safety standards, extensive scientific evidence has clearly demonstrated that non-thermal health effects produced by electromagnetic radiation do exist, are important to health, and should be taken into considera- tion when safety standards are set. This review aims to highlight some evidence of biologic effects in various body systems, and to suggest preventive measures to reduce such effects on health. Exposure to electromagnetic radiation at intensities lower than thermal safety standards has been associated with non- thermal biological effects including damage and changes to cells and DNA. This review presents evidence of such effects demonstrated in: the hematologic system, the nervous system, the immune system, the reproductive system, the skin and muscles, the cardiovascular system, glucose metabolism, and Electrohypersen- sitivity ("Microwave sickness"). Protective measures are then suggested to reduce these effects.

The Effect of Oxygen Admixture with Argon Discharges on the Impact Parameters of Atmospheric Pressure Plasma Jet Characteristics

Dry argon (Ar) discharge and wet oxygen/argon (O2/Ar) admixture discharge for alternating current atmospheric pressure plasma jets (APPJs) were studied for Ar discharges with flow rates ranging from 0.2 to 4 slm and for O2/Ar discharges with different O2 ratios and flow rates ranging from 2.5 to 15 mslm. The voltage–current waveform signals of APPJ discharge, gas flow rate, photo-imaging of the plasma jet length and width, discharge plasma power, axial temperature distribution, optical emission spectra, and irradiance were investigated. Different behavior for varying oxygen content in the admixture discharge was observed. The temperature recognizably decreased, axially, far away from the nozzle of the jet as the flow rate of dry argon decreased. Similar behavior was observed for wet argon but with a lower temperature than for dry argon. The optical emission spectra and the dose rate of irradiance of a plasma jet discharge were investigated as a function of plasma jet length, for dry and wet Ar discharges, to determine the data compatible with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) data for irradiance exposure limits of the skin, which are suitable for the disinfection of microbes on the skin without harmful effects, equivalent to 30 μJ/mm2.

Non-Ionizing Millimeter Waves Non-Thermal Radiation of Saccharomyces cerevisiae—Insights and Interactions

Non-ionizing millimeter-waves (MMW) interact with cells in a variety of ways. Here the inhibited cell division effect was investigated using 85–105 GHz MMW irradiation within the International Commission on Non-Ionizing Radiation Protection (ICNIRP) non-thermal 20 mW/cm2 safety standards. Irradiation using a power density of about 1.0 mW/cm2 SAR over 5–6 h on 50 cells/μL samples of Saccharomyces cerevisiae model organism resulted in 62% growth rate reduction compared to the control (sham). The effect was specific for 85–105 GHz range and was energy- and cell density-dependent. Irradiation of wild type and Δrad52 (DNA damage repair gene) deleted cells presented no differences of colony growth profiles indicating non-thermal MMW treatment does not cause permanent genetic alterations. Dose versus response relations studied using a standard horn antenna (~1.0 mW/cm2) and compared to that of a compact waveguide (17.17 mW/cm2) for increased power delivery resulted in complete termination of cell division via non-thermal processes supported by temperature rise measurements. We have shown that non-thermal MMW radiation has potential for future use in treatment of yeast related diseases and other targeted biomedical outcomes.

Time-temperature Thresholds and Safety Factors for Thermal Hazards from Radiofrequency Energy above 6 GHz.

Two major sets of exposure limits for radiofrequency (RF) radiation, those of the International Commission on Nonionizing Radiation Protection (ICNIRP 2020) and the Institute of Electrical and Electronics Engineers (IEEE C95.1–2019), have recently been revised and updated with significant changes in limits above 6 GHz through the millimeter wave (mm-wave) band (30–300 GHz). This review compares available data on thermal damage and pain from exposure to RF energy above 6 GHz with corresponding data from infrared energy and other heat sources and estimates safety factors that are incorporated in the IEEE and ICNIRP RF exposure limits. The benchmarks for damage are the same as used in ICNIRP IR limits: minimal epithelial damage to cornea and first-degree burn (erythema in skin observable within 48 h after exposure). The data suggest that limiting thermal hazard to skin is cutaneous pain for exposure durations less than ≈20 min and thermal damage for longer exposures. Limitations on available data and thermal models are noted. However, data on RF and IR thermal damage and pain thresholds show that exposures far above current ICNIRP and IEEE limits would be required to produce thermally hazardous effects. This review focuses exclusively on thermal hazards from RF exposures above 6 GHz to skin and the cornea, which are the most exposed tissues in the considered frequency range.

Simulation of laser-induced retinal thermal injuries for non-uniform irradiance profiles and the applicability of the laser safety standard

Significance: A validated biophysical computer model simulating retinal thermal damage thresholds is used to investigate elongated retinal images. The International Commission on Non-Ionizing Radiation Protection Guideline and the laser safety standard IEC 60825-1:2014 include a method for averaging non-uniform extended sources, however, there are no studies that have examined the applicability in detail. Our study represents a method that can also support future research in the field of eye safety. Aim: As there is currently no experimental data available for non-uniform irradiance profiles, the calculation procedure given in the laser safety standard is derived from symmetric retinal images. We aim to verify this calculation procedure for such profiles on the retina in the thermal hazard regime. Approach: A three-dimensional computer model, which solves the heat transfer equation and the Arrhenius equation describing the denaturation of the proteins in the retina, is used to simulate the threshold values for the retinal thermal injury. Three different non-uniform irradiance profiles, elliptical Gaussian, elliptical top-hat, and rectangular top-hat distributions, are investigated for a wavelength of 530 nm. The profiles are varied in their sizes and simulated for different single-pulse durations. By applying the laser safety standard, the maximum allowed energies are calculated and divided by the corresponding threshold values to obtain the reduction factor (RF) which is a crucial parameter. Results: Due to the thermal behavior in the retinal tissues, the Gaussian irradiance profiles yield larger threshold values than both top-hat profiles. Furthermore, the ratio between the threshold values and the maximum allowed energies are found to be the lowest for the Gaussian profiles. Conclusion: The simulated retinal thermal injury thresholds for the three investigated non-uniform irradiance profiles show larger RFs than the minimum RF found for symmetric profiles. This supports the applicability of the evaluation scheme of the laser safety standard for non-uniform retinal images.

Health Council of the Netherlands and evaluation of the fifth generation, 5G, for wireless communication and cancer risks.

Currently the fifth generation, 5G, for wireless communication is about to be rolled out worldwide. Many persons are concerned about potential health risks from radiofrequency radiation. In September 2017, a letter was sent to the European Union asking for a moratorium on the deployment until scientific evaluation has been made on potential health risks (http://www.5Gappeal.eu). This appeal has had little success. The Health Council of the Netherlands released on September 2, 2020 their evaluation on 5G and health. It was largely based on a World Health Organization draft and report by the Swedish Radiation Safety Authority, both criticized for not being impartial. The guidelines by the International Commission on Non-Ionizing Radiation Protection were recommended to be used, although they have been considered to be insufficient to protect against health hazards (http://www.emfscientist.org). The Health Council Committee recommended not to use the 26 GHz frequency band until health risks have been studied. For lower frequencies, the International Commission on Non-Ionizing Radiation Protection guidelines were recommended. The conclusion that there is no reason to stop the use of lower frequencies for 5G is not justified by current evidence on cancer risks as commented in this article. A moratorium is urgently needed on the implementation of 5G for wireless communication.

EXTREMELY LOW FREQUENCY ELECTROMAGNETIC EXPOSURE ASSESSMENT IN SCHOOLS: A STATISTICAL ANALYSIS OF URBAN AND SEMI-URBAN AREAS.

The aim of this research paper is to estimate the mean value of extremely low frequency (ELF) exposure in schools in Greece. Detailed ELF measurements were conducted and analyzed by the Weighted Peak Method (WPM), which estimates the overall contribution of electromagnetic waves from 1 Hz to 400 kHz, including their phases. A sample of 243 schools was sampled to calculate. The mean value of ELF magnetic fields (MFs) measured in these two groups comprising 243 schools was the principal focus of interest. ELF MF measurements taken in schools situated both far from and near ELF sources had mean and maximum values well below the current International Commission on Non-Ionizing Radiation Protection (ICNIRP) standard. The mean value of ELF MFs from all sources within the sampled schools in Greece was 0.21 μΤ. A statically significant difference between the mean MFs measured in the two groups of schools was found, but the MFs in both groups were much lower than the ICNIRP standard.

Exposure Assessment of Array Antennas at 28 GHz Using Hybrid Spherical Near-Field Transformation and FDTD Method

To protect humans from overexposure to electromagnetic (EM) fields above 6 GHz, recently revised International Commission on Non-Ionizing Radiation Protection guidelines and IEEE standard specify the basic restrictions in terms of absorbed power density (APD) and epithelial power density, respectively. To assess the EM exposure resulting from the 5G mmWave array antenna, we adopted a hybrid method that combines spherical near-field measurements and numerical dosimetry with spherical near-field transformation. Four array antennas working at 28 GHz were used as the radiation sources. The incident power density (IPD), APD, and temperature rise in a stratified body model and anatomical partial body models corresponding to different body locations were evaluated for various antenna-body distances. The results were validated by comparison with the full-wave simulations. The differences in peak spatial-average IPD and APD between two methods are below 0.08 and 1.05 dB, respectively, for the simulated cases and generally decrease with the increasing antenna-body distance. The highest heating factor for the peak spatial-average APD was approximately 0.025°C/(W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ). The results also show that the differences in APD and temperature rise caused by various exposed body locations are marginal.

Exposure of South Korean Population to 5G Mobile Phone Networks (3.4-3.8 GHz).

As industrialized countries race to install and deploy 5G networks, some countries have taken the lead and already have operational 5G networks in place. South Korea is among these. In this study, we measured exposure to electromagnetic fields in South Korea to evaluate the relative contribution of 5G as compared with other frequencies such as 2G, 3G, and 4G. Results show that the emission of 5G contributes about 15% to total telecommunications emissions. The highest levels were observed in the vicinity of 5G antennas and remain below the limits set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). © 2021 Bioelectromagnetics Society.