Effets des RF sur le système nerveux central : sommeil, EEG, vascularisation, cognition

National audienceLa plupart des études cliniques avec des champs RF ont étudié les effets d'expositions caractéristiques des téléphones portables, habituellement au niveau de la tête, sur un certain nombre de paramètres physiologiques comprenant le sommeil, l'activité électrique du cerveau, la cognition, la vascularisation cérébrale et plus généralement les systèmes cardiovasculaire et endocrinien. La majorité des études ont été effectuées chez des adultes en bonne santé. Il apparaît maintenant important d'étudier les effets des champs RF chez les enfants et les adolescents, étant donné la connaissance croissante d'une maturation continue du cerveau jusqu'à un stade avancé de l'adolescence, et quelques études récentes ont été effectuées avec des écoliers. Plusieurs études ont également porté sur des adultes qui déclarent être" électrosensibles "

Effets des radiofréquences sur le système nerveux central chez l'homme : EEG, sommeil, cognition, vascularisation

International audienceMost 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

Acute exposure to mobile phone and assessment of internal cerebral circulation in young healthy subjects : a transcranial Doppler study

International audienceThe rapid worldwide increase in the use of mobile phones raises questions about the possible adverse effects of RF fields emitted by these devices. The temporal lobe of brain is closest to the mobile phone. This may lead to relatively high energy deposition in these parts of human head during the use of mobile phone. The cerebral circulation may be potentially affected due to the exposure to RF emitted by mobile phone. Therefore the studies on cerebral blood flow are essential in order to evaluate the possible interaction exposure to RF with the central nervous system. Data in the literature related to the brain circulation are limited and controversial due to the different methods and protocols applied in these studie

Effets spécifiques d'une exposition aux ondes radiofréquences de téléphone mobile sur le contrôle nerveux autonome du tonus vasomoteur cutané

National audienceLes 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

Is the effect of mobile phone radiofrequency waves on human skin perfusion non-thermal ?

International audienceTo 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. 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. 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. Our results reveal the existence of a specific vasodilatory effect of mobile phone radiofrequency emission on skin perfusion

L'intolérance environnementale idiopathique (IEI‐CEM)

Un certain nombre de personnes signalent divers symptômes qu’elles attribuent à l’exposition aux champs électromagnétiques (CEM). Parmi ceux-ci, des maux de tête, du stress, des troubles du sommeil, etc. Jusqu’à ce jour, aucun lien de causalité entre l’exposition aux champs électromagnétiques et ces symptômes n’a été établi, ce qui a conduit l’OMS à remplacer le terme général d’hypersensibilité par celui d’ « intolérance environnementale idiopathique (IEI) avec l’attribution aux champs électromagnétiques (IEI-CEM) ». Le projet "SENSI-RF" se distingue par le fait qu’il se focalise sur des facteurs de diagnostic objectifs : endocriniens, immunitaires et biochimiques pour étudier la problématique IEI-CEM

Champs électromagnétiques et hypersensibilité : à la recherche de marqueurs biologiques

International audienceThe effects of electromagnetic field (EMF) exposure on human health raise a number of questions and became a subject of several laboratory studies. In addition to this concern about the health effects, some individuals suffer from atypical symptoms that they attribute to the effects of exposure to EMF. This syndrome is commonly known as the electrohypersensitivity (EHS) or idiopathic environmental intolerance (IEI) attributed to EMF.L’utilisation croissante des nouvelles technologies dans le domaine de la télécommunication (hautes fréquences) ou des appareils domestiques (en basses fréquences) est à l’origine d’une augmentation de l’exposition de l’homme aux champs électromagnétiques (CEM). Les effets de ce type d’exposition sur la santé humaine suscitent des questions et font l’objet de plusieurs études en laboratoire. Outre cette inquiétude sur l’effet sanitaire, certains individus souffrent de symptômes atypiques qu’ils attribuent aux effets de l’exposition aux CEM. Ce syndrome est communément appelé l’électrohypersensibilité (EHS) ou l’intolérance environnementale idiopathique (IEI) attribuée aux CEM

Effects of extremely low frequency (ELF) and radio-frequency (RF) on melatonin and cortisol, two markers of the circadian rhythms

International audienceElectromagnetic field (EMF) has becoming an integral part of our everyday life. It is a consequence of our intensive use of electricity and/or emerging technologies in mobile telecommunications. This exposure to EMF has raised questions about possible effects of the EMF on human health. It has become the object of debate and a public health concern. This has resulted in the classification of extremely low frequency (ELF)- and radiofrequency (RF)-EMF into category 2B, i.e., agents that are “possibly carcinogenic to humans” by the International Agency for Research on Cancer. It is known that cancer and neurobehavioral alterations may be associated with circadian rhythm disruption and/or effect on melatonin secretion. In addition, some Individuals living or working in an environmental exposed to EMF complain of a variety of adverse health effects. Troubled sleep and headache remain a recurrent and common symptom reported. So it is interesting to look at the EMF effect exposure on the circadian system. Since both melatonin and cortisol are major markers of the circadian system, we reviewed data from the literature on these two marker rhythms, in search of deleterious effects of EMF on both their blood levels and abnormalities in their circadian profiles (a phase-advance or a phase-delay) which would point out a rhythm desynchronization of the organism. Overall, to date no consistent evidence of the effect of exposure to RF on cortisol and melatonin. However, contradictory data are reported on ELF-EMF

Effect of mobile phone radiofrequency signal on the alpha rhythm of human waking EEG : A review

International audienceIn response to the exponential increase in mobile phone use and the resulting increase in exposure to radiofrequency electromagnetic fields (RF-EMF), there have been several studies to investigate via electroencephalography (EEG) whether RF-EMF exposure affects brain activity. Data in the literature have shown that exposure to radiofrequency signals modifies the waking EEG with the main effect on the alpha band frequency (8–13 Hz). However, some studies have reported an increase in alpha band power, while others have shown a decrease, and other studies showed no effect on EEG power. Given that changes in the alpha amplitude are associated with attention and some cognitive aspects of human behavior, researchers deemed necessary to look whether alpha rhythm was modulated under RF-EMF exposure. The present review aims at comparing and discussing the main findings obtained so far regarding RF-EMF effects on alpha rhythm of human waking spontaneous EEG, focusing on differences in protocols between studies, which might explain the observed discrepancies and inconclusive results

The effects of extremely low-frequency magnetic fields on melatonin and cortisol, two marker rhythms of the circadian system

International audienceIn the past 30 years the concern that daily exposure to extremely low-frequency magnetic fields (ELF-EMF) (1 to 300 Hz) might be harmful to human health (cancer, neurobehavioral disturbances, etc) has been the object of debate, and has become a public health concern. This has resulted in the classification of ELF-EMF into category 2B, ie, agents that are 'possibly carcinogenic to humans' by the International Agency for Research on Cancer. Since melatonin, a neurohormone secreted by the pineal gland, has been shown to possess oncostatic properties, a 'melatonin hypothesis' has been raised, stating that exposure to EMF might decrease melatonin production and therefore might promote the development of breast cancer in humans. Data from the literature reviewed here are contradictory. In addition, we have demonstrated a lack of effect of ELF-EMF on melatonin secretion in humans exposed to EMF (up to 20 years' exposure) which rebuts the melatonin hypothesis. Currently, the debate concerns the effects of ELF-EMF on the risk of childhood leukemia in children chronically exposed to more than 0.4 uT. Further research is thus needed to obtain more definite answers regarding the potential deleterious effects of ELF-EMF