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International audience; The race to install and deploy 5G has taken an important turn in industrialized countries. Certain countries have taken the lead, and 5G is already operational in these locations. South Korea is among those countries that have already deployed 5G. In this study, we conducted experimental measurements of exposure to electromagnetic fields in this country to see the contribution of 5G compared to other frequencies such as 2G, 3G and 4G. The results of the study showed that the emission of 5G is about 15% of the global level. The highest level was observed in the vicinity of the antenna and remains below the limits set by ICNIRP.

Recent studies have revealed that rodents' physiological responses to low-intensity radiofrequency (RF) electromagnetic fields were similar to thermoregulatory responses to cold conditions. The primary autonomic response to cold exposure is peripheral vasoconstriction that allows rodents to reduce heat loss and maintain a relatively constant internal body temperature. In the present study, we investigated the effects of 900 MHz RF at a low level (SAR of 0.35 W/kg) on tail skin temperature (Ttail ) in rats. We showed that rats exposed to RF had lower Ttail than control rats at ambient temperatures between 27 and 28 °C, suggesting that RF could induce a noticeable degree of vasoconstriction under mild-warm ambient temperatures. This difference in Ttail was suppressed after the intraperitoneal injection of a vasodilator, an α-adrenergic antagonist, confirming the hypothesis of the vasoconstriction in exposed rats. Moreover, like a response to cold stimuli, RF exposure led to increased plasma concentrations of important factors: noradrenaline (a neurotransmitter responsible for vasoconstriction and thermogenesis) and fatty acids (markers of activated thermogenesis). Taken together, these findings indicate that low-intensity RF levels triggered some key physiological events usually associated with responses to cold in rats. © 2021 Bioelectromagnetics Society.

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.

International audience

Autonomic nervous control during sleep play a key role in the maintenance of homeostasis in preterm neonates. Low-frequency electromagnetic (0-100 kHz) fields have been associated with alteration in such mechanisms. However, it has never been tested with high frequencies whereas preterm neonates are also chronically exposed to radiofrequencies (RF, 87.5 MHz – 5.8 GHz) while hospitalized. We investigated the influence of chronic RF exposure on autonomic nervous activity in sleeping preterm neonates...

Communication technologies based on radiofrequency (RF) propagation bring great benefits to our daily life. However, their rapid expansion raises concerns about possible impacts on public health. At intensity levels below the threshold to produce thermal effects, RF exposure has also recently been reported to elicit biological effects, resembling reactions to cold. The objective of the present study was to investigate the effects of non-thermal RF on body temperature in mice and the related mechanisms. 3-months-old C57BL/6 J mice were exposed to a continuous RF signal at 900 MHz, 20 ± 5 V.m−1 for 7 consecutive days, twice per day during the light phase, for one hour each time. The SAR was 0.16 ± 0.10 W.kg−1. We showed that body temperature patterns in mice change synchronously with the RF exposure periods. Average body temperature in the light phase in the exposed group was higher than in the control group. The expression of the TRPM8 gene was not affected by RF in trigeminal ganglia. Furthermore, the injection of a TRPM8 antagonist did not induce a temperature decrease in exposed mice, as this was the case for sham-controls. These findings indicate that 900 MHz RF exposure at non-thermal level produce a physiological effect on body temperature in mice. However, the involvement of TRPM8 receptors in the mechanism by which RF induced changes in body temperature of mice which remains to be further explored. It must then be assessed if this effect is extrapolable to man, and if this could lead to consequences on health.

BackgroundData on the effects of extremely low frequency electromagnetic fields (ELF-EMF) on pregnancy outcomes are inconclusive.ObjectiveTo study the relation between maternal cumulative exposure to ELF-EMF during pregnancy and the risk of prematurity or small for gestational age (SGA) in a pooled analysis of two French birth cohorts.MethodsElfe and Epipage2 are both population-based birth cohorts initiated in 2011 and included 18 329 and 8400 births, respectively. Health data and household, mother and child characteristics were obtained from medical records and questionnaires at maternity and during follow-up. A job exposure matrix was used to assess cumulative exposure to ELF-EMF during three periods: (1) until 15 weeks of gestation, (2) until 28 weeks of gestation and (3) until 32 weeks of gestation. Analyses were restricted to single live births in mainland France and to mothers with documented jobs (N=19 894). Adjusted logistic regression models were used.ResultsAccording to the period studied, 3.2%–4% of mothers were classified as highly exposed. Results were heterogeneous. Increased risks of prematurity were found among low exposed mothers for the three periods, and no association was observed among the most exposed (OR1=0.92 (95% CI 0.74 to 1.15); OR2=0.98 (95% CI 0.80 to 1.21); OR3=1.14 (95% CI 0.92 to 1.41)). For SGA, no association was observed with the exception of increased risk among the low exposed mothers in period 2 and the most exposed in period 3 (OR=1.25 (95% CI 1.02 to 1.53)).ConclusionSome heterogeneous associations between ELF-EMF exposure and prematurity and SGA were observed. However, due to heterogeneity (ie, their independence regarding the level of exposure), associations cannot be definitely explained by ELF-EMF exposure.

High-power microwaves are used to inhibit electronics of threatening military or civilian vehicles. This work aims to assess health hazards of high-power microwaves and helps define hazard threshold levels of modulated radiofrequency exposures such as those emitted by the first generations of mobile phones.Rats were exposed to the highest possible field levels, under single acute or repetitive exposures for eight weeks. Intense microwave electric fields at 1 MV/m of nanoseconds duration were applied from two sources at different carrier frequencies of 10 and 3.7 GHz. The repetition rate was 100 pps, and the duration of train pulses lasted from 10 s to twice 8 min. The effects were studied on the central nervous system, by labelling brain inflammation marker GFAP and by performing different behavioural tests: rotarod, T-maze, beam-walking, open-field, and avoidance test. Long-time survival was measured in animals repeatedly exposed, and anatomopathological analysis was performed on animals sacrificed at two years of life or at death if earlier. One group was sham exposed.Few effects were observed on behaviour. With acute exposure, an avoidance reflex was shown at very high, thermal level (22 W/kg); GFAP was increased some days after exposure. Most importantly, with repeated exposures, survival time was 4-month shorter in the exposed group, with eleven animals exhibiting a large sub-cutaneous tumour, compared to two in the sham group. A residual X-ray exposure was also present in the beam (0.8 Gy), which is not a bias for the observed result.High power microwaves below thermal level in average, can increase cancer incidence and decrease survival time in rats, without clear effects on behaviour. The parameters of this effect need to be explored further, and a more precise dosimetry to be performed.

Communication technologies bring great benefits to our daily life. Besides, this rapid expansion has raised concerns about their possible impact on public health. In this study, a repeated exposure to a low intensity 900 MHz radiofrequency induced changes in body temperature of mice. To look for a mechanism, we tried to identify a molecular or functional target of interaction with radiowaves. The cold receptor TRPM8 seemed to be involved, as its antagonist AMG2850 was inhibited in exposed animals.

A multi-band body-worn distributed exposure meter (BWDM) is designed and calibrated for diffuse fields in a reverberation chamber (RC) for personal exposure assessment in indoor environments. The BWDM uses 22 nodes distributed over the torso and measures the incident power density ( $S_{\mathrm{ inc}}$ ) on body for 11 telecommunication bands in the frequency range of 790–5513 MHz. In order to calibrate the measurement device in diffuse fields, a protocol is proposed for on-body calibration of the BWDM. This protocol is applicable to wearable personal exposure meters in general. The BWDM and the proposed calibration protocol are validated in five indoor locations and five frequency bands (the downlink bands at 800, 900, 1800, and 2100 MHz as well as Wi-Fi 2 GHz) using a tri-axial broadband antenna and a spectrum analyzer (SA). The calibration shows that the BWDM has a relatively low measurement uncertainty with a 68% confidence interval on its antenna apertures, in the range 3.4–5.5 dB. A maximum difference of 0.9 dB is obtained for the total exposure in the test areas between the measurements of the BWDM and SA, which is an excellent agreement.

This paper studies the effect of antenna polarization on measurement uncertainty of a multi-band body-worn distributed exposure meter (BWDM). The BWDM is a device for assessing electromagnetic fields in real environments accurately. The BWDM consists of 8 nodes and is calibrated on the body for simultaneous measurement of the incident power density in four frequency bands. Each node contains an antenna that can have two potential antenna polarizations.The BWDM is calibrated on four human subjects in an anechoic chamber to determine its measurement uncertainty in terms of 68% confidence interval (CI68) of the on-body antenna aperture. The results show that using a fixed polarization of the antennas on body can lead to a different CI68 up to maximum 4.9 dB when worn by another person which is still 9.6 dB lower than the measurement uncertainty of commercial exposure meters.

Individuals who suffer from idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) complain of a variety of adverse health effects. Troubled sleep remains a recurrent and common symptom in IEI-EMF individuals. Melatonin, a circadian hormone, plays a major role in the sleep process. In this study, we compared levels of melatonin between a sensitive group (IEI-EMF, n = 30) and a non-sensitive control group (non IEI-EMF, n = 25) without exposure to electromagnetic sources. Three questionnaires were used to evaluate the subjective quality and sleep quantity: the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index and the Spiegel Sleep Inventory. Melatonin was quantified in saliva and its major metabolite 6-sulfatoxymelatonin (aMT6s) in urine. Melatonin levels were compared by a two-way analysis of variance at various times between the control and IEI-EMF group. Despite significantly different sleep scores between the two groups, with a lower score in the IEI-EMF group (P 0.05) and urine aMT6s (P > 0.05). Bioelectromagnetics. 37:175-182, 2016. © 2016 Wiley Periodicals, Inc.

International audience; Context : In France, cases of people self-reporting symptoms due to electromagnetic fields (EMF) or idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) have emerged over the past 10 years. Several self-help and action groups have claimed an increasing number of members. However, little is known about this population in France. Aim : Our primary objective was to describe the reported symptoms and the sources that may induce these symptoms through a questionnaire-based study. Secondly, we discussed our results alongside those obtained from the existing literature and provide an overview of this physical condition. Subjects and methods : From April to November 2014, a self-questionnaire survey was conducted in France. With 52 participants, the average age of respondents was 50 ± 11 years and the majority of participants at 79% were women. Results : Our study results in the French population were consistent with findings in the literature conducted in other countries and also highlighted a number of emerging EMF sources such as wireless area networks, to be perceived as possible causes of symptoms. Conclusions : Despite methodological differences, we summarized facts from previous comparable investigations. We also provided an overview of people claiming EMF effects and briefly discussed possible avenues of research.

A multi-band Body-Worn Distributed exposure Meter (BWDM) calibrated for simultaneous measurement of the incident power density in 11 telecommunication frequency bands, is proposed. The BDWM consists of 22 textile antennas integrated in a garment and is calibrated on six human subjects in an anechoic chamber to assess its measurement uncertainty in terms of 68% confidence interval of the on-body antenna aperture. It is shown that by using multiple antennas in each frequency band, the uncertainty of the BWDM is 22 dB improved with respect to single nodes on the front and back of the torso and variations are decreased to maximum 8.8 dB. Moreover, deploying single antennas for different body morphologies results in a variation up to 9.3 dB, which is reduced to 3.6 dB using multiple antennas for six subjects with various body mass index values. The designed BWDM, has an improved uncertainty of up to 9.6 dB in comparison to commercially available personal exposure meters calibrated on body. As an application, an average incident power density in the range of 26.7-90.8 muW.m - 2 is measured in Ghent, Belgium. The measurements show that commercial personal exposure meters underestimate the actual exposure by a factor of up to 20.6.

Use of non-ionizing radiation (NIR) for diagnostic purposes allows non-invasive assessment of the structure and function of the human body and is widely employed in medical care. ICNIRP has published previous statements about the protection of patients during medical magnetic resonance imaging (MRI), but diagnostic methods using other forms of NIR have not been considered. This statement reviews the range of diagnostic NIR devices currently used in clinical settings; documents the relevant regulations and policies covering patients and health care workers; reviews the evidence around potential health risks to patients and health care workers exposed to diagnostic NIR; and identifies situations of high NIR exposure from diagnostic devices in which patients or health care workers might not be adequately protected by current regulations. Diagnostic technologies were classified by the types of NIR that they employ. The aim was to describe the techniques in terms of general device categories which may encompass more specific devices or techniques with similar scientific principles. Relevant legally-binding regulations for protection of patients and workers and organizations responsible for those regulations were summarized. Review of the epidemiological evidence concerning health risks associated with exposure to diagnostic NIR highlighted a lack of data on potential risks to the fetus exposed to MRI during the first trimester, and on long-term health risks in workers exposed to MRI. Most of the relevant epidemiological evidence that is currently available relates to MRI or ultrasound. Exposure limits are needed for exposures from diagnostic technologies using optical radiation within the body. There is a lack of data regarding risk of congenital malformations following exposure to ultrasound in utero in the first trimester and also about the possible health effects of interactions between ultrasound and contrast media.

International audience; Purpose: To assess the level of various salivary and urinary markers of patients with electromagnetic hypersensitivity (EHS) and to compare them with those of a healthy control group. Materials and methods: We analyzed samples from 30 EHS individuals and a matched control group of 25 individuals (non-EHS) aged between 22 and 66. We quantified cortisol both in saliva and urine, alpha amylase (sAA), immunoglobulin A and C Reactive Protein levels in saliva and neopterin in urine (uNeopterin). Results: sAA was found to be significantly higher (p

BackgroundData on the effects of extremely low frequency electromagnetic fields (ELF-EMF) on pregnancy outcomes are inconclusive.ObjectivesTo study the relation between maternal cumulative exposure to ELF-EMF during pregnancy and the risk of prematurity or small for gestational age in a pooled analysis of two French birth cohorts.MethodsElfe and Epipage2 are both population-based birth cohorts initiated in 2011 and included 18 329 and 8400 births respectively. Health data and household, mother and child characteristics were obtained from medical records, by face-to-face interview at maternity, and completed during follow-up. A recently updated job-exposure-matrix (JEM) was used to assess cumulative exposure to ELF-EMF during three periods: 1) until 15, 2) until 28 and 3) until 32 weeks of gestation. Analyses were restricted to single live births in mainland France and to mothers with documented jobs (n=19,894). Differences in selection frame between the two cohorts were controlled using a propensity score weighting method. We used multiple imputation method to deal with missing data. Logistic regression models adjusted for the main potential confounders were used.ResultsAccording to the period studied, 3.2% to 4% of mothers were classified as highly exposed to ELF-EMF. An increased risk of spontaneous prematurity was observed among the most exposed groups in period 2 and period 3. Overall, no consistent association with small for gestational age was found.ConclusionThis study, with substantial statistical power provides evidence of a possible association between cumulative exposure to ELF-EMF during pregnancy and the risk of spontaneous prematurity.

Background Despite the widespread and increasing use of electricity in working environments, occupational exposure to ELF-EMF during pregnancy has been rarely documented and was often assessed using the mothers’ self-report. Our first aim was to assess maternal occupational exposure to ELF-EMF during pregnancy in the birth cohort study Elfe. Secondly, we studied the link between this exposure and child’s gestational age or birth-weight. Methods The Elfe study was initiated in 2011 in France and enrolled more than 18,000 infants born between 33 and 42 weeks’ gestation. Mother’s job title was collected by a face-to-face interview and coded using the International Standard „Classification of Occupation 1968 (ISCO68). The Bowman population-based job exposure matrix (JEM) was used to assess arithmetic-mean-workday ELF-EMF exposure level associated to the occupation held by each mother during pregnancy, expressed in µT/day. This JEM used the Standard Occupational Classification system 1980 (SOC80). ISCO68 codes were translated to their SOC80 equivalent. Exposure levels were categorised according to quartiles and 90th percentile. Multiple linear regression models were used to estimate adjusted differences in mean birth-weight and mean gestational age between exposure groups. Results A total of 13,340 mothers worked during their pregnancy. Job was coded into SOC80 for 12,671 mothers and mean-workday level was defined for 12,549. Adjusted models did not show differences between any of the exposure groups and the reference category for both birth-weight and gestational age among children born at 33 weeks’ gestation or more. Conclusion Our study, in a large birth cohort, is the first to assess maternal occupational exposure during pregnancy using a JEM based on industrial hygiene measurements. Our next aim will be to use the INTEROCC ELF-JEM (http://www.crealradiation.com), an updated version of the Bowman ELF-JEM. We will also assess environmental exposure to ELF-EMF during pregnancy and its possible association with birth outcomes.

International audience; Cell phones increase exposure to radiofrequency (RF) electromagnetic fields (EMFs). Whether EMFs exert specific effects on biological systems remains debatable. This study investigated the effect of cell phone exposure on the structure and function of human NADPH-cytochrome P450 reductase (CPR). CPR plays a key role in the electron transfer to cytochrome P450, which takes part in a wide range of oxidative metabolic reactions in various organisms from microbes to humans. Human CPR was exposed for 60 min to 1966-MHz RF inside a transverse electromagnetic cell (TEM-cell) placed in an incubator. The specific absorption rate (SAR) was 5 W·kg− 1. Conformation changes have been detected through fluorescent spectroscopy of flavin and tryptophan residues, and investigated through circular dichroism, dynamic light scattering and microelectrophoresis. These showed that CPR was narrowed. By using cytochrome C reductase activity to assess the electron flux through the CPR, the Michaelis Menten constant (Km) and the maximum initial velocity (Vmax) decreased by 22% as compared with controls. This change was due to small changes in the tertiary and secondary structures of the protein at 37 °C. The relevance of these findings to an actual RF exposure scenario demands further biochemical and in-vivo confirmation.

Individuals who suffer from idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) complain of a variety of adverse health effects. Troubled sleep remains a recurrent and common symptom in IEI-EMF individuals. Melatonin, a circadian hormone, plays a major role in the sleep process. In this study, we compared levels of melatonin between a sensitive group (IEI-EMF, n = 30) and a non-sensitive control group (non IEI-EMF, n = 25) without exposure to electromagnetic sources. Three questionnaires were used to evaluate the subjective quality and sleep quantity: the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index and the Spiegel Sleep Inventory. Melatonin was quantified in saliva and its major metabolite 6-sulfatoxymelatonin (aMT6s) in urine. Melatonin levels were compared by a two-way analysis of variance at various times between the control and IEI-EMF group. Despite significantly different sleep scores between the two groups, with a lower score in the IEI-EMF group (P 0.001), no statistical difference was found between the two groups for saliva melatonin (P 0.05) and urine aMT6s (P 0.05). Bioelectromagnetics. 37:175-182, 2016. © 2016 Wiley Periodicals, Inc.

International audience; In this paper, the authors present a comprehensive review of animal studies on carcinogenicity of radiofrequency (RF) electromagnetic fields. The rapid increase in mobile telephony has resulted in concerns regarding possible heath effects from the low-level but increasingly ubiquitous exposure to RF fields. The possible carcinogenicity of RF fields has been investigated in a number of experimental models including classical rodent bioassays, studies using genetically predisposed animals, cocarcinogenicity studies, and studies evaluating effects on the development of tumors from transplanted tumor cells. Overall, the results of these studies are rather consistent and indicate no carcinogenic effects at exposure levels relevant to human exposure from mobile phones. This finding is consistent with the results of the majority of epidemiological studies on mobile phone users, and suggests that RF field exposure below the present guidelines is not likely to cause cancer.

The rapid development and expansion of mobile communications contributes to the general debate on the effects of electromagnetic fields emitted by mobile phones on the nervous system. This study aims at measuring the glial fibrillary acidic protein (GFAP) expression in 48 rat brains to evaluate reactive astrocytosis, three and 10 days after long-term head-only sub-chronic exposure to a 900 MHz electromagnetic field (EMF) signal, in male rats.Sprague-Dawley rats were exposed for 45 min/day at a brain-averaged specific absorption rate (SAR) = 1.5 W/kg or 15 min/day at a SAR = 6 W/kg for five days per week during an eight-week period. GFAP expression was measured by the immunocytochemistry method in the following rat brain areas: Prefrontal cortex, cerebellar cortex, dentate gyrus of the hippocampus, lateral globus pallidus of the striatum, and the caudate putamen.Compared to the sham-treated rats, those exposed to the sub-chronic GSM (Global System for mobile communications) signal at 1.5 or 6 W/kg showed an increase in GFAP levels in the different brain areas, three and ten days after treatment.Our results show that sub-chronic exposures to a 900 MHz EMF signal for two months could adversely affect rat brain (sign of a potential gliosis).

International audience; The effects of exposure to radiofrequency electromagnetic fields (EMF), specifically related to the use of mobile telephones, on the nervous system in humans have been the subject of a large number of experimental studies in recent years. There is some evidence of an effect of exposure to a Global System for Mobile Telecommunication (GSM)-type signal on the spontaneous electroencephalogram (EEG). This is not corroborated, however, by the results from studies on evoked potentials. Although there is some evidence emerging that there may be an effect of exposure to a GSM-type signal on sleep EEG, results are still variable. In summary, exposure to a GSM-type signal may result in minor effects on brain activity, but such changes have never been found to relate to any adverse health effects. No consistent significant effects on cognitive performance in adults have been observed. If anything, any effect is small and exposure seems to improve performance. Effects in children did not differ from those in healthy adults. Studies on auditory and vestibular function are more unequivocal: neither hearing nor the sense of balance is influenced by short-term exposure to mobile phone signals. Subjective symptoms over a wide range, including headaches and migraine, fatigue, and skin itch, have been attributed to various radiofrequency sources both at home and at work. However, in provocation studies a causal relation between EMF exposure and symptoms has never been demonstrated. There are clear indications, however, that psychological factors such as the conscious expectation of effect may play an important role in this condition.

International audience; The world-wide and rapidly growing use of mobile phones has raised serious concerns about the biological and health-related effects of radio frequency (RF) radiation, particularly concerns about the effects of RFs upon the nervous system. The goal of this study was conducted to measure cytochrome oxidase (CO) levels using histochemical methods in order to evaluate regional brain metabolic activity in rat brain after exposure to a GSM 900 MHz signal for 45 min/day at a brain-averaged specific absorption rate (SAR) of 1.5 W/Kg or for 15 min/day at a SAR of 6 W/Kg over seven days. Compared to the sham and control cage groups, rats exposed to a GSM signal at 6 W/Kg showed decreased CO activity in some areas of the prefrontal and frontal cortex (infralimbic cortex, prelimbic cortex, primary motor cortex, secondary motor cortex, anterior cingulate cortex areas 1 and 2 (Cg1 and Cg2)), the septum (dorsal and ventral parts of the lateral septal nucleus), the hippocampus (dorsal field CA1, CA2 and CA3 of the hippocampus and dental gyrus) and the posterior cortex (retrosplenial agranular cortex, primary and secondary visual cortex, perirhinal cortex and lateral entorhinal cortex). However, the exposure to GSM at 1.5 W/Kg did not affect brain activity. Our results indicate that 6 W/Kg GSM 900 MHz microwaves may affect brain metabolism and neuronal activity in rats.

The potential health risks of radiofrequency electromagnetic fields (RF EMFs) emitted by mobile phones are currently of considerable public interest. The present study investigated the effect of exposure to 900 MHz GSM radiofrequency radiation on steroid (cortisol and testosterone) and pituitary (thyroid-stimulating hormone, growth hormone, prolactin and adrenocorticotropin) hormone levels in 20 healthy male volunteers. Each subject was exposed to RF EMFs through the use of a cellular phone for 2 h/day, 5 days/ week, for 4 weeks. Blood samples were collected hourly during the night and every 3 h during the day. Four sampling sessions were performed at 15-day intervals: before the beginning of the exposure period, at the middle and the end of the exposure period, and 15 days later. Parameters evaluated included the maximum serum concentration, the time of this maximum, and the area under the curve for hormone circadian patterns. Each individual's pre-exposure hormone concentration was used as his control. All hormone concentrations remained within normal physiological ranges. The circadian profiles of prolactin, thyroid-stimulating hormone, adrenocorticotropin and testosterone were not disrupted by RF EMFs emitted by mobile phones. For growth hormone and cortisol, there were significant decreases of about 28% and 12%, respectively, in the maximum levels when comparing the 2-week (for growth hormone and cortisol) and 4-week (for growth hormone) exposure periods to the pre-exposure period, but no difference persisted in the postexposure period. Our data show that the 900 MHz EMF exposure, at least under our experimental conditions, does not appear to affect endocrine functions in men.

Because of the increasing use of mobile phones, the possible risks of radio frequency electromagnetic fields adverse effects on the human brain has to be evaluated. In this work we measured GFAP expression, to evaluate glial evolution 2, 3, 6 and 10 days after a single GSM exposure (15 min, brain averaged SAR = 6 W/kg, 900 MHz signal) in the rat brain. A statistically significant increase of GFAP stained surface area was observed 2 days after exposure in the frontal cortex and the caudate putamen. A smaller statistically significant increase was noted 3 days after exposure in the same areas and in the cerebellum cortex. Our results confirm the Mausset-Bonnefont et al. study [Mausset-Bonnefont, A.L., Hirbec, H., Bonnefont, X., Privat, A., Vignon, J., de Seze, R., 2004. Acute exposure to GSM 900 MHz electromagnetic fields induces glial reactivity and biochemical modifications in the rat brain. Neurobiol. Dis. 17, 445–454], showing the existence of glial reactivity after a 15 min GSM acute exposure at a brain averaged SAR of 6 W/kg. We conclude to a temporary effect, probably due to a hypertrophy of glial cells, with a temporal and a spatial modulation of the effect. Whether this effect could be harmful remains to be studied.

The increasing use of mobiles phones (MP) has raised the problem of the effects of daily electromagnetic fields (EMF) exposure on human health. To date several studies have been published concerning the effects of acute MP exposure on psychomotor performances. This study investigated the effects of daily exposure to GSM 900 type MP on cognitive function. Fifty-five subjects (27 male and 28 female) were divided into two groups: a group with MP switched on and a group with MP switched off. The two groups were matched according to age, gender, and IQ. This double blind study lasted for 45 days and was divided in three periods: baseline (BLP, 2 days), exposure (EP, 27 days), and recovery (RP, 13 days). Subjects were exposed during EP and sham exposed during RP for 2 h/day, 5 days/week. The neuropsychological test battery composed of 22 tasks screened four neuropsychological categories: information processing, attention capacity, memory function, and executive function. This neuropsychological battery was performed four times on day 2 (BLP), day 15 (EP), day 29 (EP), and day 43 (RP). Our results indicate that daily MP use has no effect on cognitive function after a 13-h rest period.

Immunohistochemistry is a powerful tool to detect neurotransmitter (NT) presence in different brain structures with a high spatial resolution. However, it is only scarcely used in quantitative approach due to lack of reproducibility and sensitivity. We developed a protocol of NT detection based on immunohistochemistry and image analysis to show that this approach could also be useful to evaluate NT content variations. We focused our study on the GABAergic system in the cerebellum and measured different accurate parameters, namely the optical density (O.D.), the stained area and the number of immunoreactive cells in each cerebellar cell layer. In order to modify the GABA content, we used gamma-vinyl-GABA (GVG), an inhibitor of GABA-transaminase, known to dramatically increase GABA concentration in the central nervous system (CNS) and especially in the cerebellum. We observed a significant increase in the three parameters measured in the molecular and the granular layers of the cerebellum after treatment with GVG, reflecting the well-established increase in GABA content after such a treatment. Therefore, our technical approach allows not only a precise determination of the effects in particular cell layers but also a semi-quantification of GABA content variations. This technique could be suitable for monitoring NT variations following any treatment.

Some studies have shown that people living near a mobile phone base station may report sleep disturbances and discomfort. Using a rat model, we have previously shown that chronic exposure to a low-intensity radiofrequency electromagnetic field (RF-EMF) was associated with paradoxical sleep fragmentation and unusually greater vasomotor tone in the tail without any difference of central temperature at air temperature (Ta) of 31°C. Thus, in the present study, we tested the hypothesis that sleep disturbances are due to thermal discomfort induced by RF-EMF, since the lower skin temperature might be accompanied by a change in thermal preference. In this study, the animal was free to choose Ta value (thermal preference), included in the rat’s thermoneutral zone. Within this range, homeothermia can be maintained by controlling changes in peripheral vasomotor tone and by modulating wakefulness and sleep stage distribution. The present study aimed at assessing the changes in thermal preference and sleep stage distribution in 18 young male Wistar rats.

The effects of 100-mT, 0.8-Hz square-wave magnetic fields on the growth of chemically induced tumors in mice were investigated. Tumors were initiated using one injection of benzo(a)pyrene (either 0.2 mg or 2.0 mg/animal). Male and female mice (Balb/c, C3H and C57/bl/6 strains) were exposed for 8 h/day from the onset of tumor until death or until the tumor volume reached a predetermined volume. Statistically significant decrease in the rate of tumor growth and increase in survival were observed in all cases. Results are discussed in terms of previous published work and of possible mechanisms.

Exposure of children to Radiofrequency (RF) and Extremely Low Frequency (ELF) electromagnetic fields (EMF) has not been assessed for large samples, despite their growing use and their potential health effects. Studies are needed to take into account every source of children exposure, including emerging ones, with longitudinal design to capture changes while growing, from in-utero to the adolescence. Aims: to characterize and follow RF and ELF exposure in children of the French ELFE birth cohort. Methods: 18918 children born in 2011 have been included. RF and ELF exposure will be assessed by questionnaires. Jobs and company activity of the mothers will be coded with international classifications, and a job-exposure matrix will be applied to assess maternal occupational exposure during pregnancy. Domestic uses (Wi-Fi, cordless phone, mobile phone, electrical appliances, transportation means…) will be collected on questionnaires. Residential exposure will be assessed by using geocoded residential addresses and mapping of EMF sources. An exposure study will be performed in a subgroup of 400 children (when 3.5 yrs old). Housing and household characteristics and a time-activity diary will be completed, and numerous RF bands and 50 Hz ELF will be measured at different places in each room and in the main places where the child spends time during 24h. Results: questionnaires at birth, 2 months, 1 year, 2 years of life have been already administered, and follow-up at 3.5 years is scheduled in 2014-2015 Jobs performed by mothers during pregnancy are coded. Perspectives: Interactions between EMF and other radiations or chemical exposures will be studied, in relation with health outcomes collected at each follow-up. Other collected factors influencing children’s health and development (social, psychological, medical and familial factors), will allow an accurate assessment of the etiology of health events. Future collaboration with other international birth cohorts to better understand the etiology of rare diseases such as pediatric cancers will be considered.

Les résultats de l'étude effectuée sur 20 jeunes adultes par approche laser Doppler thermostatique (LD), ont révélé des effets thermiques de téléphone mobile qui étaient potentialisés par l'exposition réelle aux ondes RF sur le micro débit sanguin cutané en comparaison avec une exposition sham. Un test de provocation thermique spécifique induisant une hyperémie réactive effectué à la 25è minute post-exposition, a montré que la réserve vasodilatatrice des microvaisseaux cutanés exposés aux ondes RF était plus grande que celle sous exposition sham.

L'homéostasie énergétique est maintenue grâce aux différents flux d'énergie qui sont régis par l'activité des grandes fonctions homéostasiques et leurs interactions. Ces flux comprennent les entrées énergétiques (prise alimentaire) et les sorties ou économies (vasomotricité, sommeil). Cette balance énergétique est primordiale pour les organismes en développement car l'énergie permet d'assurer le bon fonctionnement des fonctions vitales, de la thermorégulation et de la croissance. Actuellement, avec l'essor de la téléphonie mobile et des antennes-relais, les connaissances physiologiques sur les effets d'une exposition chronique aux ondes radiofréquences (RF), surtout de faible intensité, sont lacunaires. Dans cette étude, nous avons voulu déterminer les effets d'une exposition à un champ radiofréquence d'antenne-relais sur les 3 principales fonctions impliquées dans la balance énergétique: le cycle veille/sommeil, la thermorégulation et le comportement alimentaire. Ces fonctions ont été étudiées chez le rat juvénile (modèle de développement humain) à 2 températures ambiantes (Ta), 24ºC et 31ºC., qui appartiennent à la zone de thermoneutralité chez le rat Wistar. Dans cette zone de neutralité thermique, le maintien de l'homéothermie est assuré uniquement par des mécanismes vasomoteurs périphériques et la production de chaleur métabolique est minimale.

Objective To establish whether SkBF can be modified by exposure to the radiofrequency waves emitted by a mobile phone when the latter is held against the jaw and ear. Methods Variations in SkBF and Tsk in adult volunteers were simultaneously recorded with a thermostatic laser Doppler system during a 20-minute “radiofrequency” exposure session and a 20-minute “sham” session. The skin microvessels’ vasodilatory reserve was assessed with a heat challenge at the end of the protocol. Results During the radiofrequency exposure session, SkBF increased (vs. baseline) more than during the sham exposure session. The sessions did not differ significant in terms of the Tsk time-course response. The skin microvessels’ vasodilatory ability was found to be greater during radiofrequency exposure than during sham exposure. Conclusions Our results reveal the existence of a specific vasodilatory effect of mobile phone radiofrequency emission on skin perfusion.

International audience; Most of clinical studies on radiofrequency electromagnetic fields (RF) were directed at mobile phone-related exposures, usually at the level of the head, at their effect on some physiological functions including sleep, brain electrical activity (EEG), cognitive processes, brain vascularisation, and more generally on the cardiovascular and endocrine systems. They were frequently carried out on healthy adults. Effects on the amplitude of EEG alpha waves, mainly during sleep, look reproducible. It would however be important to define more precisely whether and how the absence of electromagnetic disturbance between RF exposure and the recording systems is checked. No consensus arises about cognitive effects. Some effects on cerebral vascularisation need complementary work.; La plupart des études cliniques avec des champs radiofréquences (RF) ont porté sur les effets d'expositions caractéristiques des téléphones portables, habituellement au niveau de la tête, sur un certain nombre de fonctions physiologiques comprenant le sommeil, l'activité électrique du cerveau (EEG), la cognition, la vascularisation cérébrale et, plus généralement, les systèmes cardiovasculaire et endocrinien. La majorité des études a été effectuée chez des adultes en bonne santé. L'effet décrit sur l'amplitude des ondes alpha de l'EEG, notamment pendant le sommeil, semble reproductible. Il semble cependant important de préciser si et comment l'absence d'interférence entre l'exposition RF et l'enregistrement est vérifiée. Il ne se dégage pas de consensus sur des effets cognitifs. Quelques effets décrits sur la vascularisation cérébrale nécessitent des études complémentaires.

International audience; The effects of radiofrequency electromagnetic fields (RF-EMF) on the control of body energy balance in developing organisms have not been studied, despite the involvement of energy status in vital physiological functions. We examined the effects of chronic RF-EMF exposure (900 MHz, 1 Vm-1) on the main functions involved in body energy homeostasis (feeding behaviour, sleep and thermoregulatory processes). Thirteen juvenile male Wistar rats were exposed to continuous RF-EMF for 5 weeks at 24 °C of air temperature (Ta) and compared with 11 non-exposed animals. Hence, at the beginning of the 6th week of exposure, the functions were recorded at Ta of 24 °C and then at 31 °C. We showed that the frequency of rapid eye movement sleep episodes was greater in the RF-EMF-exposed group, independently of Ta (+42.1 % at 24 °C and +31.6 % at 31 °C). The other effects of RF-EMF exposure on several sleep parameters were dependent on Ta. At 31 °C, RF-EMF-exposed animals had a significantly lower subcutaneous tail temperature (-1.21 °C) than controls at all sleep stages; this suggested peripheral vasoconstriction, which was confirmed in an experiment with the vasodilatator prazosin. Exposure to RFEMF also increased daytime food intake (+0.22 gh-1). Most of the observed effects of RF-EMF exposure were dependent on Ta. Exposure to RF-EMF appears to modify the functioning of vasomotor tone by acting peripherally through a- adrenoceptors. The elicited vasoconstriction may restrict body cooling, whereas energy intake increases. Our results show that RF-EMF exposure can induce energy-saving processes without strongly disturbing the overall sleep pattern.

This study investigated the effects of a chronic exposure to radiofrequency electromagnetic fields designed to simulate a current chronic exposure from antennae base station on the energy balance in juvenile rats. The results showed a decrease in body cooling and an increase in energy saving. Most effects due to the exposure were dependent on the ambient temperature.

The maintenance energy balance is relevant for growing organisms since energy is required for optimal functioning of vital functions. We studied the possible effects of chronic exposure to radiofrequency electromagnetic fields emitted by mobile phone base stations on three functions involved in the control of energy balance (sleep, thermoregulation and feeding) in juvenile rats. The results showed no sleep pattern disturbance but the animals were in a state of energy saving.

Disturbances of sleep by radiofrequency electromagnetic radiation (RF-EMR) emitted by mobile phone base stations type GSM are not well-established. This may be explained by the fact that this environmental factor is not strong enough to be significant. Additional stress (e.g. thermal stress) could increase adverse RF-effects on sleep. However, studies are usually carried out in adults exposed to thermoneutrality (even though not strictly controlled). Moreover, there is a lack of information concerning growing organisms for which sleep is particularly important since it promotes cerebral and body restitutions. In this study, it is held that RF-EMR exposition could potentiate sleep disturbances through interaction with thermal stress in juvenile rats. 13 Wistar rats (3 weeks-old) exposed to RF-EMR during 5 weeks were compared to a non exposed control group (n=11). One week after surgery, sleep was measured on different days (00-06 pm) at thermoneutrality (environmental temperature: 24+-1°C) and in a warm environment (31+-1°C), combined or not with RF exposure. Sleep was visually scored in 30 second-periods in Wakefulness (W), Slow Wave (SWS) and Paradoxical Sleep (PS). The total durations of sleep stages, the mean durations and the frequencies of the episodes were analyzed with ANOVA. RF exposure did not modify total sleep stage and wakefulness durations. However, when compared to non exposed group, significant RF-effects were found at 31°C but not at 24°C: W and SWS episodes were longer but less frequent (W: 7.0 vs 5.0 min, 0.9 vs 1.8 episodes.h-1 ; SWS: 3.2 vs 2.8 min, 12.1 vs 14.2 episodes.h-1 ; always p

National audience; Les résultats de l'étude effectuée sur 21 jeunes adultes volontaires ont révélé des effets athermiques de l'exposition réelle aux ondes RF de téléphone mobile sur le micro débit sanguin cutané en comparaison avec une exposition sham, par approche laser Doppler thermostatique (LD). L'analyse spectrale du signal LD en fin d'exposition a permis de montrer que ces modifications de vasomotricité cutanée étaient associées à une activité nerveuse sympathique locale plus élevée sous exposition réelle que sous exposition sham. Un test de provocation thermique spécifique induisant une hyperémie réactive maximale effectué à la 25è minute post-exposition a montré que la réserve vasodilatatrice des micro-vaisseaux cutanés exposés aux ondes RF était plus grande que celle sous exposition sham.