In situ magnetic field exposure and ICNIRP-based safety distances for electronic article surveillance systems

Effects of Intermediate Frequency (150 kHz) Electromagnetic Radiation on the Vital Organs of Female Sprague Dawley Rats

Exposure to electromagnetic radiation (EMR) from intermediate frequency sources has increased exponentially in recent years. The consequences of this exposure on biological systems are prompting scientists to study the effects on human health. This current study aimed to determine the effects of intermediate frequency (150 kHz) EMR exposure on the vital organs of female Sprague Dawley rats. The EMR group (n = 10 animals) was exposed to a frequency of 150 kHz with an intensity of 65 ± 15 μW/cm2 for two months. The control group (n = 10 animals) was exposed to an intensity of 35 ± 15 nW/cm2. Haematological, histochemical, gross, and histopathological profiles of all major organs of all animals were then performed using standard procedures. All major organs generally showed no significant detectable effects in either the control or EMR groups. However, gross and histopathological examinations revealed the effects of EMR on the liver and lungs, which showed inflammatory changes without significant biochemical/haematological manifestations. In addition, a significant increase in serum sodium level and a decrease in serum urea level were also observed in the EMR group. It can be concluded that the current frequency and duration of exposure trigger the changes in the liver and lungs but are not sufficient to cause clinical and functional manifestations. Therefore, a long-term exposure study might be helpful to determine the effects of 150 kHz IF EMR on these organs.

Assessment of combined exposure to intermediate-frequency electromagnetic fields and pulsed electromagnetic fields among library workers in Japan

Objective

To assess exposure levels to electromagnetic fields (EMFs) among library workers in Japan, focusing on co-exposure to intermediate-frequency EMF (IF-EMF) and pulsed EMF, to propose a new epidemiological research methodology.

Methods

The evaluated exposure sources were an electromagnetic type-electronic article surveillance gate (EM-EAS, IF-EMF (operating frequency 220 Hz-14 kHz)) and an activator/deactivator of anti-theft tags termed as “book check unit” (BCU, pulsed EMF). Short-term exposures were: (E1) whole-body exposure from the EAS gate when sitting within 3 m; (E2) local exposure to transient IF-EMF while passing through or beside the EAS gate; and (E3) local exposure to a pulsed magnetic field on BCU use. E1–E3 were evaluated based on exposure levels relative to magnetic flux density at the occupational reference level (RL; E1) or as per occupational basic restrictions (BR; E2 and E3) delineated by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2010 guidelines. Exposure indices based on mid-term exposure (D1–D3), assuming exposure according to employment on a weekly basis, were used to assess exposure in actual working conditions. D1 represents continuous exposure from an EAS gate when sitting within 3 m of the gate. D2 and D3 represent repeated transient exposures occurring during gate pass or on the operation of a BCU. A link to a web-based questionnaire was distributed to librarians working at all libraries where the authors had mailed institutional questionnaires (4,073 libraries). Four exposure patterns were defined according to various exposure scenarios.

Results

We obtained information on exposure parameters and working conditions from the 548 completed questionnaires. The ICNIRP guideline levels were not exceeded in any of the E1–E3 scenarios. Median of the D1 (% ICNIRP RL × hour/week) was 1, and >85% respondents had values <10. However, the maximum value was 513. Altogether, these results indicate that continuous exposure was low in most cases. The same tendency was observed regarding repeated transient exposure from EM-EAS gates (i.e., the median value for D2 (% ICNIRP BR × gate pass) was 5). However, there were several cases in which D1 and D2 values were >10 times the median. The median of D3 (% ICNIRP BR × BCU operation) was 10, and most respondents' D3 values were greater than their D2 values, although the derived results depended on the assumptions made for the estimation.

Conclusion

We conducted an assessment of combined exposures to IF-EMF and pulsed EMF among library workers in Japan by evaluating both short-term exposures (E1–E3) and exposure indices based on mid-term exposures (D1–D3) assuming actual working conditions per questionnaire results. These results provide useful information for future epidemiological studies.

Measurement and Exposure Assessment of Intermediate Frequency Magnetic Fields From Electronic Article Surveillance (EAS) Gates in Libraries

Exposure to magnetic fields from the electronic article surveillance (EAS) gate was evaluated in consideration of the application to epidemiological studies of library workers who are exposed continually to intermediate frequency magnetic fields from the EAS gate. Two types of exposures were investigated. One was transient exposure due to passing through or beside the gate and another was chronic exposure in the room. We measured magnetic fields from five EAS gate models which were commonly used in libraries in Japan. Detailed measurements were performed for two of them in consideration of the phase difference of vector components of magnetic flux density. The polarization of the magnetic field in the gate was investigated with the index of ellipticity. The induced electric field in a human body was numerically calculated for exposures to magnetic fields of the two gate models. The results provide a quantitative understanding of exposures during passing through or by the EAS gate. Magnetic field distribution was measured in a large room for one gate model to quantify the chronic exposure of library workers during the work at the desk. It was found that the magnetic field was distributed as a function of the horizontal distance to the nearest gatepost. The 45-point average value BIEC defined by the IEC standard was suggested to be a useful quantity to characterize the magnitude of the magnetic field from the EAS gate. Exposures to different EAS gates are expected to be compared through this quantity without detailed measurements. These results are expected to provide useful means for exposure assessment of epidemiological studies on the association between the IF-EMF exposure and possible health outcomes.

A Review of the Effect of the Intermediate Frequency Electromagnetic Fields on Female Reproduction

ABSTRACT

The use of intermediate frequency (IF) fields in occupational equipment and domestic appliances is increasing dramatically. The World Health Organization consistently points out that there is a lack of scientific evidence to assess the reproductive risk in female species within the exposure limits as stated by the International Commission on Non-Ionizing Radiation Protection. The purpose of this review paper is to review the available literature on the effects of IF EMR on female reproduction in all species and to fully understand these effects. A literature review of experimental, epidemiological, in vivo, and in vitro literature from the 1800s to the present was conducted. Very few studies have been conducted on the effects of IF on female reproduction. The study of women in their workplace, laboratory rats and mice, and chicken embryos has yielded conflicting results on the dangers of IF. Some reports consider IF harmful during pregnancy, while other results show an insignificant (p < 0.05) correlation between the exposed group and the unexposed groups. The experiments conducted so far restrict several parameters such as field strength, frequency, and modulation to draw definitive conclusions. In two experiments, this frequency range is considered safe for non-invasive treatment of cancerous and noncancerous ovarian cells in the initial phase. Evaluation of the IF range on reproduction should be a priority for research. This review shows that there are few reports in this field, and they all contradict each other on whether the IF field is harmful or not. Nonetheless, IF is used in medicine to treat cancer and is currently being researched for non-cancerous cells. More comprehensive IF studies should be conducted to address the limitations in these summary studies.

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

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.

Characterisation of personal exposure to environmental radiofrequency electromagnetic fields in Albacete (Spain) and assessment of risk perception

In the last decades, exposure to radiofrequency electromagnetic fields (RF-EMF) has substantially increased as new wireless technologies have been introduced. Society has become more concerned about the possible effects of RF-EMF on human health in parallel to the increase in their exposure. The appearance of personal exposimeters opens up wide-ranging research possibilities. Despite studies having characterised personal exposure to RF-EMF, part of the population is still worried, to the extent that psychogenic diseases ("nocebo" effect) appear, and patients suffer. It could be interesting to share personal exposure results with the population to better understand and promote public health. The main objective was to characterise personal exposure to environmental RF-EMF in Albacete (166,000 inhabitants, SE Spain), and assess the effect of sharing the results of the study on participants' risk perception. Measurements were taken by a personal Satimo EME SPY 140 exposimeter, which was programmed every 10 s for 24 h. To measure personal exposure to RF-EMF, we worked with 75 volunteers. Their personal exposure, 14 microenvironments in the city, e.g., home, outdoors, work, etc., and possible time differences were analysed. After participating in the study, 35 participants completed a questionnaire about their RF-EMF risk perception, which was also answered by a control sample to compare the results (N = 36). The total average exposure of 14 bands was 37.7 μW/m², and individual ranges fell between 0.2 μW/m², recorded in TV4&5, and a maximum of 264.7 μW/m² in DECT. For Friday, we recorded a mean of 53.9 μW/m² as opposed to 23.4 μW/m² obtained on Saturday. The recorded night-time value was 27.5 μW/m² versus 43.8 μW/m² recorded in the daytime. The mean personal exposure value also showed differences between weekdays and weekend days, with 39.7 μW/m² and 26.9 μW/m², respectively. The main source that contributed to the mean total personal exposure was enhanced cordless telecommunications (DECT) with 50.2%, followed by mobile phones with 18.4% and mobile stations with 11.0% (GSM, DCS and UMTS), while WiFi signals gave 12.5%. In the analysed microenvironments, the mean exposure of homes and workplaces was 34.3 μW/m² and 55.2 μW/m², respectively. Outdoors, the mean value was 34.2 μW/m² and the main sources were DECT, WiFi and mobile phone stations, depending on the place. The risk perception analysis found that 54% of the participants perceived that RF-EMF were less dangerous than before participating in the study, while 43% reported no change in their perceptions. Only 9% of the volunteers who received information about their measurements after the study assessed the possible RF-EMF risk with a value over or equal to 4 (on a scale from 1 to 5) versus 39% of the non-participant controls. We conclude that personal exposure to RF-EMF fell well below the limits recommended by ICNIRP and showed wide temporal and spatial variability. The main exposure sources were DECT, followed by mobile phones and WiFi. Sharing exposure results with participants lowered their risk perception.

Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach

INTRODUCTION

In 2011, the International Agency for Research on Cancer classified radiofrequency (RF) electromagnetic fields (EMF) as possibly carcinogenic to humans (group 2B), although the epidemiological evidence for the association between occupational exposure to RF-EMF and cancer was judged to be inadequate, due in part to limitations in exposure assessment. This study examines the relation between occupational RF and intermediate frequency (IF) EMF exposure and brain tumor (glioma and meningioma) risk in the INTEROCC multinational population-based case-control study (with nearly 4000 cases and over 5000 controls), using a novel exposure assessment approach.

METHODS

Individual indices of cumulative exposure to RF and IF-EMF (overall and in specific exposure time windows) were assigned to study participants using a source-exposure matrix and detailed interview data on work with or nearby EMF sources. Conditional logistic regression was used to investigate associations with glioma and meningioma risk.

RESULTS

Overall, around 10% of study participants were exposed to RF while only 1% were exposed to IF-EMF. There was no clear evidence for a positive association between RF or IF-EMF and the brain tumors studied, with most results showing either no association or odds ratios (ORs) below 1.0. The largest adjusted ORs were obtained for cumulative exposure to RF magnetic fields (as A/m-years) in the highest exposed category (≥90th percentile) for the most recent exposure time window (1-4 years before the diagnosis or reference date) for both glioma, OR = 1.62 (95% confidence interval (CI): 0.86, 3.01) and meningioma (OR = 1.52, 95% CI: 0.65, 3.55).

CONCLUSION

Despite the improved exposure assessment approach used in this study, no clear associations were identified. However, the results obtained for recent exposure to RF electric and magnetic fields are suggestive of a potential role in brain tumor promotion/progression and should be further investigated.

Measurements of intermediate-frequency electric and magnetic fields in households

Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300Hz to 1MHz) as well as potential effects of IF fields on the human body remains limited, although the range of household appliances with electrical components working in the IF range has grown significantly (e.g., induction cookers and compact fluorescent lighting). In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields in the IF range typically present in residences as well as emitted by a wide range of household appliances under real-life circumstances. Using spot measurements, residential IF field levels were found to be generally low, while the use of certain appliances at close distance (20cm) may result in a relatively high exposure. Overall, appliance emissions contained either harmonic signals, with fundamental frequencies between 6kHz and 300kHz, which were sometimes accompanied by regions in the IF spectrum of rather noisy, elevated field strengths, or much more capricious spectra, dominated by 50Hz harmonics emanating far in the IF domain. The maximum peak field strengths recorded at 20cm were 41.5V/m and 2.7A/m, both from induction cookers. Finally, none of the appliance emissions in the IF range exceeded the exposure summation rules recommended by the International Commission on Non-Ionizing Radiation Protection guidelines and the International Electrotechnical Commission (IEC 62233) standard at 20cm and beyond (maximum exposure quotients EQ_E 1.0 and _EQ_H 0.13).

Review of Studies Concerning Electromagnetic Field (EMF) Exposure Assessment in Europe: Low Frequency Fields (50 Hz-100 kHz)

We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.

A Source-based Measurement Database for Occupational Exposure Assessment of Electromagnetic Fields in the INTEROCC Study: A Literature Review Approach

INTRODUCTION

To date, occupational exposure assessment of electromagnetic fields (EMF) has relied on occupation-based measurements and exposure estimates. However, misclassification due to between-worker variability remains an unsolved challenge. A source-based approach, supported by detailed subject data on determinants of exposure, may allow for a more individualized exposure assessment. Detailed information on the use of occupational sources of exposure to EMF was collected as part of the INTERPHONE-INTEROCC study. To support a source-based exposure assessment effort within this study, this work aimed to construct a measurement database for the occupational sources of EMF exposure identified, assembling available measurements from the scientific literature.

METHODS

First, a comprehensive literature search was performed for published and unpublished documents containing exposure measurements for the EMF sources identified, a priori as well as from answers of study subjects. Then, the measurements identified were assessed for quality and relevance to the study objectives. Finally, the measurements selected and complementary information were compiled into an Occupational Exposure Measurement Database (OEMD).

RESULTS

Currently, the OEMD contains 1624 sets of measurements (>3000 entries) for 285 sources of EMF exposure, organized by frequency band (0 Hz to 300 GHz) and dosimetry type. Ninety-five documents were selected from the literature (almost 35% of them are unpublished technical reports), containing measurements which were considered informative and valid for our purpose. Measurement data and complementary information collected from these documents came from 16 different countries and cover the time period between 1974 and 2013.

CONCLUSION

We have constructed a database with measurements and complementary information for the most common sources of exposure to EMF in the workplace, based on the responses to the INTERPHONE-INTEROCC study questionnaire. This database covers the entire EMF frequency range and represents the most comprehensive resource of information on occupational EMF exposure. It is available at www.crealradiation.com/index.php/en/databases.

In situ exposure assessment of intermediate frequency fields of diverse devices

In this study, in situ exposure assessment of both electric and magnetic fields of different intermediate frequency (IF) sources is investigated. The authors investigated smart boards and touchscreens, energy-saving bulbs, fluorescent lamps, a portable hearing unit and an electrosurgical unit (ESU). For most of these sources, the electric field is the dominating quantity. International Commission on Non-Ionizing Radiation Protection reference levels are exceeded for touchscreens (44 kHz: up to 155.7 V m(-1) at 5 cm), energy-saving bulbs (38-52 kHz: up to 117.3 V m(-1)), fluorescent lamps (52 kHz: up to 471 V m(-1) at 5 cm) and ESUs (up to 920 kHz: 792 V m(-1) at 0.5 cm). Magnetic field strengths up to 1.8 and 10.5 A m(-1) were measured close to the ESU and portable hearing unit (69 V m(-1)), respectively. Large differences of measured field values exist among the various operating modes of the IF equipment. Compliance distances for general public range from 15.3 cm (touchscreen) to 25 cm (fluorescent lamps).

Compliance boundaries for train protection systems

Occupational exposure to non-ionising electromagnetic radiation emitted by train protection (TP) systems operating at ∼27 MHz is investigated in situ. In total, five TP systems of two different types, i.e. KVB (Contrôle de Vitesse par Balises) and TBL1+ (Transmission Balise-Locomotive), are considered. For each type, the boundaries outside which the field levels are in compliance with the International Commission on Non-Ionizing Radiation Protection guidelines for occupational exposure ('compliance boundaries') are determined. Maximal fields of 4.7 A m(-1) and 0.2 kV m(-1) for KVB, and 51 A m(-1) and 1.5 kV m(-1) for TBL1+ are measured, at distances between 10 and 25 cm from the respective antennas. Compliance boundaries for occupational exposure are maximally 0.6 m for KVB to 1 m for TBL1+, while no specific compliance boundary is needed for the general public.

Occupational and public field exposure from communication, navigation, and radar systems used for air traffic control

Electromagnetic exposure (occupational and general public) to 14 types of air traffic control (ATC) systems is assessed. Measurement methods are proposed for in situ exposure assessment of these ATC systems. In total, 50 sites are investigated at 1,073 locations in the frequency range of 255 kHz to 24 GHz. For all installations, typical and maximal exposure values for workers and the general public are provided. Two of the 14 types of systems, Non-Directional Beacons (NDB) (up to 881.6 V m) and Doppler Very High Frequency (VHF) Omni-directional Range (DVOR) (up to 92.3 V m), exhibited levels requiring recommended minimum distances such that the ICNIRP reference levels are not exceeded. Cumulative exposure of all present radiofrequency (RF) sources is investigated, and it is concluded that the ATC source dominates the total exposure in its neighborhood.