Search

Exposure to external extremely low-frequency (ELF) electric and magnetic fields induces the development of electric fields inside the human body, with their nature depending on multiple factors including the human body characteristics and frequency, amplitude, and wave shape of the field. The objective of this study was to determine whether active implanted cardiac devices may be perturbed by a 50 or 60 Hz electric field and at which level. A numerical method was used to design the experimental setup. Several configurations including disadvantageous scenarios, 11 implantable cardioverter-defibrillators, and 43 cardiac pacemakers were tested in vitro by an experimental bench test up to 100 kV/m at 50 Hz and 83 kV/m at 60 Hz. No failure was observed for ICNIRP public exposure levels for most configurations (in more than 99% of the clinical cases), except for six pacemakers tested in unipolar mode with maximum sensitivity and atrial sensing. The implants configured with a nominal sensitivity in the bipolar mode were found to be resistant to electric fields exceeding the low action levels, even for the highest action levels, as defined by the Directive 2013/35/EU. Bioelectromagnetics. 2020;41:136-147. © 2020 Bioelectromagnetics Society.

Numerous studies have been carried out on the potential effects of an extremely low frequency (ELF-0-300 Hz) magnetic field (MF) on human health. However, there is limited data on the effect of a high exposure level to ELF MFs for a prolonged period. Therefore, the objective of this pilot work was to demonstrate the feasibility of a study evaluating the stress hormone concentrations resulting from a 10-min exposure to a 60 Hz MF of several tens of thousands of µT. In this pilot study, human volunteers were thus exposed for the first time to a 60 Hz, 50 mT MF for a duration of 10 min. Stress hormone levels were measured before (once), during (twice) and after (once) this 10-min exposure period. The small sample size (n = 5) did not allow to conduct standard inferential statistical tests and no conclusion regarding the exposure effects can be drawn. However, this study demonstrates the feasibility of using a simple blood testing material in a protocol testing for the effect of a 10-min exposure to a high MF level in healthy human volunteers. © 2022 Bioelectromagnetics Society.

In light of concerns regarding the occupational safety and health of workers wearing active implantable medical devices (AIMDs), this study aims to investigate the potential risks of electromagnetic interference (EMI) between AIMDs and low-frequency 50/60 Hz electromagnetic fields (EMFs) in the workplace. A total of 58 AIMDs, consisting of pacemakers (PMs) and implantable cardiac defibrillators (ICDs) of different brands, models, and configurations were tested to determine the immunity thresholds for high-voltage electric fields (EFs) and magnetic fields (MFs) at 50/60 Hz. The EFs and MFs at the levels in workplaces are reproduced by setups using Helmholtz coils and aluminum plates, respectively, to ensure that the EM/MF exposures are controllable and reproducible. The EMI thresholds were recorded by observing the occurrences of PM or ICD dysfunctions. In addition, numerical studies on anatomical models were carried out using CST® software. The results indicate that the recorded thresholds all exceed the EF and MF public exposure limits given in the ICNIRP 2010 guidelines. No dysfunction was observed among four ICDs tested under MF exposure up to 2750 µT at 50 Hz and 2480 µT at 60 Hz. However, among the 43 PMs and 11 ICDs tested under EF exposures, potential hazards may occur below the occupational exposure level proposed in the ICNIRP guidelines.

Assessing the exposure of adults to magnetic field is a central point in the context of epidemiological studies. The EXPERS study is the first study at national scale in Europe with measurements of personal exposure to extremely low frequency magnetic fields, involving 1046 French adults with 24 h personal measurements. The proportion of adults with a 24 h AM of ≥ 1 µT was 2.1% for all adults and 0.3% for adults for which no alarm clock was identified, as this requirement of the measurement protocol was sometimes not respected. The alarm clocks were the main variable linked to the adults’ exposure measurements. The vicinity of the home to a high voltage power line increased the magnetic field exposure. However, only 1.7% of the adults were living close to a 63 to 400 kV overhead line, and only one of them had a personal exposure ≥ 1 μT with an AM of 1.1 μT. The exposure of adults was also correlated with some characteristics of the home and its environment, and some durations of activities, such as the duration of work and the duration in rail transport. The distribution of adults’ personal exposure was significantly different from the distribution of exposure during sleep, and from the distribution of exposure assessed from measurements during sleep and work. This highlights the complexity of the exposure assessment in epidemiological studies.

Cluster analysis was applied to characterize indoor personal exposure to Extremely Low Frequency magnetic field (ELF MF) in children with respect to the type and distance of electric networks near the child home. An association effect analysis was then applied to investigate the possible impact of environmental variables, such as heating type, age and size of the home, and family size on the exposure patterns identified with cluster analysis. Cluster analysis identified three different patterns of exposure: the first one was of children with the highest exposure living near overhead lines of high (63-150 kV), extra-high (225 kV) and ultra-high voltage (400 kV); the second one was of children with mid exposures living near underground networks of low (400V) to mid voltage (20 kV) and substations; the last one was of children with lowest level of exposure living far from electric networks. Electric heating, or living in big buildings or in larger families led to higher levels of exposures.

Innovative approaches, such as stochastic dosimetry and Machine Learning, can be complementary to traditional methods for electromagnetic field (EMF) exposure assessment, overcoming limitations and allowing extraction of new/deeper information. In this study, two examples of innovative EMF exposure assessment approaches are presented: (i) a stochastic approach based on low rank tensor approximations to assess indoor exposure to WLAN access point with unknown location and (ii) an application of Machine Learning to characterize indoor residential exposures to ELF magnetic field in children by considering the type of electric networks near the child home, the age and type of the child home, the type of heating and the family size.

Personal exposure to Extremely Low Frequency Magnetic Fields (ELF MF) in children is a very timely topic. We applied cluster analysis to 24 h indoor personal exposures of 884 children in France to identify possible common patterns of exposures. We investigated how electric networks near child home and other variables potentially affecting residential exposure, such as indoor sources of ELF MF, the age and type of the residence and family size, characterized the magnetic field exposure patterns. We identified three indoor personal exposure patterns: children living near overhead lines of high (63&ndash, 150 kV), extra-high (225 kV) and ultra-high voltage (400 kV) were characterized by the highest exposures, children living near underground networks of low (400 V) and mid voltage (20 kV) and substations (20 kV/400 V) were characterized by mid exposures, children living far from electric networks had the lowest level of exposure. The harmonic component was not relevant in discriminating the exposure patterns, unlike the 50 Hz or broadband (40&ndash, 800 Hz) component. Children using electric heating appliances, or living in big buildings or in larger families had generally a higher level of personal indoor exposure. Instead, the age of the residence was not relevant in differentiating the exposure patterns.

Current guidelines and recommendations limiting human exposure to extremely low frequency (ELF) magnetic field (MF) are based on the most reliable acute human neurophysiological exposure responses. However, the currently available perception thresholds are established on small sample size and non-replicated experiments. The current human study aimed to test MF levels leading to mahnetophosphenes perceptions at 20, 50, 60 and 100 Hz. Perception reported button-press were recorded in these 4 frequency groups in 55 randomly assigned magnetic flux density conditions. Results showed a frequency-dependent threshold for initial perception: 2.51 T/s at 20 Hz, 6.28 T/s at 50 Hz, 7.54 T/s at 60 Hz, and 12.57 T/s at 100 Hz; and for the 50% detection rate: 4.73 T/s at 20 Hz, 8.83 T/s at 50 Hz, 10.55 T/s at 60 Hz, and 33.46 T/s at 100 Hz. Since it is a linear correlate of the induced in-situ E-fields, the dB/dt metric was chosen to analyse the the data. It confirmed lower magnetophoshene perception at lower frequencies for a similar in-situ induced E-field.

Characterization of children exposure to extremely low frequency (ELF) magnetic fields is an important issue because of the possible correlation of leukemia onset with ELF exposure. Cluster analysis&mdash, a Machine Learning approach&mdash, was applied on personal exposure measurements from 977 children in France to characterize real-life ELF exposure scenarios. Electric networks near the child&rsquo, s home or school were considered as environmental factors characterizing the exposure scenarios. The following clusters were identified: children with the highest exposure living 120&ndash, 200 m from 225 kV/400 kV overhead lines, children with mid-to-high exposure living 70&ndash, 100 m from 63 kV/150 kV overhead lines, children with mid-to-low exposure living 40 m from 400 V/20 kV substations and underground networks, children with the lowest exposure and the lowest number of electric networks in the vicinity. 63&ndash, 225 kV underground networks within 20 m and 400 V/20 kV overhead lines within 40 m played a marginal role in differentiating exposure clusters. Cluster analysis is a viable approach to discovering variables best characterizing the exposure scenarios and thus it might be potentially useful to better tailor epidemiological studies. The present study did not assess the impact of indoor sources of exposure, which should be addressed in a further study.

In this study we characterized children exposure to extremely low frequency (ELF) magnetic fields using cluster analysis - a Machine Learning approach. Indoor personal exposure measurements from 977 children in France were analyzed to discover how electric networks near child home or school could influence exposure patterns. 225 kV/400 kV overhead lines characterized the cluster of children with the highest exposure; 63 kV/150 kV overhead lines characterized the cluster with mid-to-high exposure; 400 V/20 kV substations and underground networks characterized mid-to-low exposures. 400 V/20 kV overhead lines and 63-225 kV underground networks had a marginal contribution in differentiating and characterizing the exposure clusters.

The assessment of magnetic field exposure in children is an important point in the context of epidemiological issues. EXPERS is the first study ever carried out measuring personal exposure to extremely low frequency magnetic fields at a national scale, involving 977 French children with 24 h personal measurements. Descriptive statistical analyses were performed for all the children, and only for children where no alarm clock was identified, as in some cases this requirement of the measurement protocol was not respected. The proportion of children with a 24 h arithmetic mean of ≥0.4 μT was 3.1% when considering all children and 0.8% when excluding alarm clocks. The alarm clocks were the main variable linked to the child exposure measurements. Magnetic field exposure increased when the home was located close to a high voltage power line. However, none of the 0.8% of children living at125 m to a 225 kV line or200 m to a 400 kV overhead line had a personal exposure of0.4 μT. A multiple correspondence analysis showed the difficulty to build a statistical model predicting child exposure. The distribution of child personal exposure was significantly different from the distribution of exposure during sleep, questioning the exposure assessment in some epidemiological studies.

The paper describes a novel approach based on Machine Learning (ML) to characterize the exposure of children to extremely low frequency magnetic field (ELF-MF, 40-800Hz). Unsupervised cluster analysis is applied on MF registrations from a cohort 977 children during 24h. The aim is to better characterize children exposure with respect to daily activities, subject location, environmental conditions.

The risk of malfunction of cardiac implant due to the influence of external electromagnetic field has been highlighted by the 2013/35/EU European Directive, which classified implanted workers as workers at particular risk. We propose in this study a new method to test in vitro cardiac implants with an electric field of 50 Hz. The exposure system was designed using numerical simulations and does not need to be installed in a high voltage laboratory. The influence of electric fields up to 250 kV/m was tested on 11 implanted cardiac defibrillators. The results give the parameters of the implants that are linked with a malfunction for electric field higher or lower than action levels. This is useful approach for risk assessment for workers wearing cardiac implants.

Thisstudy aims to compute 50 Hz electric field interferences on pacemakers for diverse lead configurations and implantation positions. Induced phenomena in a surface-based virtual human model (standing male grounded with arms closed, 2 mm resolution) are computed for vertical exposure using CST EM® 3D software, with and without an implanted pacemaker. Induced interference voltages occurring on the pacemaker during exposure are computed and the results are discussed. The bipolar mode covers 99% of the implanted pacing leads in the USA and Europe, according to statistics. The tip-to-ring distance of a lead may influence up to 46% of the induced voltage. In bipolar sensing mode, right ventricle implantation has a 41% higher induced voltage than right atrium implantation. The induced voltage is in average 10 times greater in unipolar mode than in bipolar mode, when implanted in the right atrium or right ventricle. The electric field threshold of interference for a bipolar sensing mode in the worst case setting is 7.24 kV·m−1, and 10 times higher for nominal settings. These calculations will be completed by an in vitro study.

Presents dans notre environnement les rayonnements electromagnetiques (EM) suscitent de multiples questions quant a leurs effets potentiels pour les porteurs de dispositifs medicaux actifs implantes (DMAI). Le nombre croissant de porteurs d’implants medicaux, y compris dans la population active, a entraine un questionnement quant a leur comportement en presence d’un champ EM. L’interaction entre le corps humain et les champs EM reste complexe et depend de multiples facteurs tels que la frequence, la puissance et la modulation des champs. Nous presentons ici une revue de cette problematique dans le cas des champs EM basse frequence.

Resume Objectif Connaitre chez les medecins generalistes francais, leur perception du risque sur les champs electromagnetiques (CEM) et la sante, leurs sources d’information ainsi que le niveau de preoccupation de leurs patients. Methodologie Six cents generalistes francais, recrutes (selectionnes) selon la methode des quotas, ont repondu a 24 questions administrees via Internet selon la methode Computer-Assisted Web Interviewing (CAWI). Resultats Les principales sources de CEM etaient connues : antennes relais, telephones portables, lignes a haute tension, fours a micro-ondes et le reseau WiFi. Les trois premieres etaient le plus souvent a l’origine d’interrogations ou de plaintes chez les patients. L’information des medecins provenait plutot des medias grand public que des sources medico-scientifiques classiques. Leur connaissance sur les risques eventuels a ete jugee insuffisante. Discussion et conclusion Nous n’avons pas observe une attitude homogene des medecins par manque evident de maitrise d’une situation complexe et mal renseignee. Un reel effort d’information est indispensable et serait parfaitement recu par les medecins conscients de leur responsabilite en matiere de conseil, de diagnostic et de soin.

Purpose of the study. Pacemakers (PM) or implantable cardioverter-defibrillators (ICD) can be disturbed by magnetic field exposure at work. Based on experimental exposure of volunteers and our experience from in situ case studies, we present an approach to evaluate work safety and the worker's fitness in such situations. Method. For the PMs situations, there are data allowing to make a decision in the majority of the cases. In the case of ICD, an adapted study is necessary. A protocol for risk evaluation was finalized, consisting in measuring the magnetic field in the various places where the worker may move within the framework of his professional activity. These measures are made in his presence, while simultaneously monitoring the operation of the device. Results. Three practical realized cases of measurements are presented, with their difficulties of realization and their results. Conclusion. A decision about the worker's fitness can then be taken on the basis of this information. This approach can be extended to the other medical implants and with electromagnetic spectrum frequencies different from 50 Hz.

Un defibrillateur automatique implantable (DAI) a ete implante chez un travailleur d’EDF potentiellement expose a un champ magnetique 50 Hz eleve. Le fonctionnement du DAI peut theoriquement etre perturbe par les expositions aux champs magnetiques rencontrees au cours de l’activite professionnelle. A partir de cette etude de cas, nous presentons une approche pour evaluer l’aptitude au travail dans ce type de situation. Le protocole consiste a mesurer le champ magnetique aux differents endroits ou le travailleur est susceptible d’aller au cours de son activite professionnelle, et en sa presence, a surveiller en meme temps le fonctionnement du DAI. Il s’agissait d’un DAI de marque Medtronic, programme en mode bipolaire. Dans les differents lieux, le champ magnetique maximum mesure au niveau du DAI a ete de 650 µT. Aucun dysfonctionnement n’a ete enregistre en mode bipolaire. Suite a ces mesures et controles du DAI, l’agent a ete declare apte et a repris ses fonctions professionnelles anterieures. Deux ans apres, aucun incident n’a ete rapporte.

Although a few studies have found that extremely low-frequency (ELF, < 300 Hz) magnetic fields (MF) can modulate human standing balance, the acute effects of electromagnetic fields (EMF) on standing balance have not been systematically investigated. This work aims to establish the threshold for standing balance modulation during ELF MF exposure. One hundred volunteers will be exposed to an ELF MF (0 to 160 Hz, 0 to 100 mT) and stimulated using transcranial electric stimulation (DC and AC, 1 mA). The displacement of their center of pressure will be collected and analyzed using validated sway characteristics to detect modulations of vestibular function. Future protocols will be designed to test for possible effects due to exposures in the radiofrequency range (i.e. above 3 kHz). These results will contribute to the literature documenting exposure guidelines aiming to protect workers and the general public.

Resume Objectifs Le but de ce travail etait d’etudier les caracteristiques anatomo-pathologiques des polypes adenomateux (PA) et non adenomateux (PNA) et des cancers colorectaux (CCR) diagnostiques en Ile de France. Materiels et methodes Les pathologistes ont rempli une fiche d’identification avec les donnees histologiques pour chaque examen histopathologique recu entre le 20/09/02 et le 20/12/02 et comportant au moins un polype ou un CCR chez un malade residant en Ile de France. Resultats La participation des structures d’anatomo-cyto-pathologie (ACP) a l’etude a ete de 73,3 %. Un total de 10 396 malades porteurs de 16 681 lesions a ete inclus. Les lesions correspondaient a 1 223 CCR chez 1 107 malades, 9 280 PA et 6 178 PNA. L’âge moyen des malades ayant un CCR etait de 68 ans, celui des malades ayant au moins un PA sans CCR de 62 ans, et celui des malades ayant au moins un PNA sans CCR ni PA de 58 ans. Le nombre moyen de polypes par malade etait de 1,4 et augmentait avec l’âge. Les PA etaient en moyenne de plus grande taille que les PNA, et leur taille augmentait avec l’âge, contrairement a celle des PNA. Le stade pTNM des cancers diagnostiques sur piece operatoire etait le suivant: pT0, 1 % pT1, 4 % pT2, 13 %, pT3, 63 % pT4, 19 % N0, 55 % N1, 24 % N2, 19 % Nx, 2 %. Conclusion Cette etude permet de preciser les caracteristiques des cancers et polypes colorectaux en Ile de France, region sans registre de cancer. Sa repetition pourrait aider a l’evaluation de la campagne de depistage de ces lesions dans la population generale.

Position du probleme Cette etude avait pour objectif d’estimer la survie a 5 ans par localisation, sexe et stade des malades d’Ile-de-France ayant presente un nouveau cancer en 1994. Methode Une etude de cohorte a debute en 1994 par un recueil exhaustif des cancers incidents declares en affection de longue duree en Ile-de-France a l’Assurance Maladie (27 080 patients). Un echantillon constitue par sondage stratifie sur la localisation tumorale a ete suivi a 1 an, 3 ans et 5 ans. L’analyse de la survie observee a ete effectuee selon la methode de Kaplan Meier. La survie relative a ete calculee selon la methode d’Ederer II. Resultats L’echantillon de suivi concernait 4 166 patients. Tous cancers confondus, la survie relative a 5 ans etait de 65 % pour les femmes et de 51 % pour les hommes. Le taux de survie relative a 5 ans etait de 82 % pour les femmes presentant un cancer du sein (98 % pour les patientes en stade I) et de 66 % pour celles presentant un cancer du col de l’uterus. La survie relative a 5 ans pour les cancers du colon etait de 67 % pour les hommes et de 54 % pour les femmes. Pour le cancer du poumon, le taux de survie relative chute de 47 % pour les patients en stade I a 5 % pour ceux en stade IV. Conclusion Notre etude apporte des resultats en terme de survie au niveau d’une region entiere couvrant 20 % de la population francaise. La survie depend de la precocite du diagnostic mais aussi de la qualite de la prise en charge therapeutique, de l’importance de l’offre, l’acces aux soins pouvant etre un facteur favorisant. Si en terme d’incidence, la situation en Ile-de-France est proche de la situation nationale, la survie a 5 ans pour un ensemble de tumeurs parait plutot globalement meilleure qu’au niveau national. En dehors des donnees de mortalite et de l’estimation des incidences, les donnees de l’assurance maladie permettent d’apporter un eclairage complementaire sur l’epidemiologie des cancers et contribuer a la connaissance de ces maladies.

Objectives This study examined the risk of interference by high magnetic flux density with permanent pacemakers. Background Several forms of electromagnetic energy may interfere with the functions of implanted pacemakers. No clinical study has reported specific and relevant information pertaining to magnetic fields near power lines or electrical appliances. Methods A total of 250 consecutive tests were performed in 245 recipients of permanent pacemakers during 12-lead electrocardiographic monitoring. A dedicated exposure system generated a 50-Hz frequency and maximum 100-μT flux density, while the electrical field was kept at values on the order of 0.10 V/m. Results A switch to the asynchronous mode was recorded in three patients with devices programmed in the unipolar sensing configuration. A sustained mode switch was followed by symptomatic pacing inhibition in one patient. No effect on devices programmed in bipolar sensing was observed, except for a single interaction with a specific capture monitoring algorithm. Conclusions The overall incidence of interaction by a magnetic field was low in patients tested with a wide variety of conventionally programmed pacemaker models. A magnetic field pulsed at power frequency can cause a mode switch and pacing inhibition in patients with devices programmed in the unipolar sensing configuration. The risk of interference appears negligible in patients with bipolar sensing programming.

Resume Un probleme de plus en plus frequent Les sources d’interferences electromagnetiques pouvant alterer le fonctionnement des stimulateurs cardiaques (PM) et des defibrillateurs automatiques implantables (DAI) sont de plus en plus nombreuses et couvrent toute la gamme de frequences, de 0 a 300 GHz, dont les tres basses frequences (ELF) et les radiofrequences (RF). Pour les porteurs de ces appareils, les consequences possibles peuvent aller d’un affaiblissement de leur bien-etre, sans repercussion clinique, a une situation perilleuse. Stimulation cardiaque Les stimulateurs cardiaques et les defibrillateurs automatiques implantables sont le plus souvent bien proteges contre les interferences exterieures. En stimulation cardiaque, elles sont assez bien apprehendees et les consequences sont, en general, faibles. Dans le domaine de la defibrillation Une interference peut etrea l’origine d’un fonctionnement inapproprie de l’appareil, la premiere consequence etant pour le patient de recevoir un choc indu ou, au contraire, de ne pas recevoir de traitement lorsqu’il en a besoin. Pour les DAI, les donnees de la litterature incitent a plus de prudence, notamment avec les portiques antivol.

The risk of perturbation of a cardiac pacemaker by an electromagnetic field has been studied for many years. However the instructions given to the patient remain vague, especially concerning electric and magnetic fields linked to electricity. In the context of Directive 2013/35/UE, this paper discusses the level of risk for 50 Hz electric and magnetic fields. Different studies on pacemaker interferences, with different methodologies are compared. The results are coherent and show the importance of pacemaker parameters for risk of interference : the type of electrodes (unipolar or bipolar) and the sensitivity threshold. When the magnetic field is lower than the reference level recommended for the general public in Europe, and when the PM is in bipolar mode with usual settings, no interference with clinical consequences were observed. These results may be used for workers exposed to electromagnetic fields, if the magnetic field levels are equivalent.

International audience; Public concern for the compatibility of electromagnetic (EM) sources with active implantable medical devices (AIMD) has prompted the development of new systems that can perform accurate exposure studies. EM field interference with active cardiac implants (e. g. implantable cardioverter-defibrillators (ICDs)) can be critical. This paper describes a magnetic field (MF) exposure system and the method developed for testing the immunity of ICD to continuous-wave MFs. The MFs were created by Helmholtz coils, housed in a Faraday cage. The coils were able to produce highly uniform MFs up to 4000 mu T at 50 Hz and 3900 mu T at 60 Hz, within the test space. Four ICDs were tested. No dysfunctions were found in the generated MFs. These results confirm that the tested ICDs were immune to low frequency MFs.

Introduction Les travailleurs porteurs d’implants medicaux sont definis comme des travailleurs a risque particulier dans la directive 2013/35/UE, qui doit etre transposee dans la legislation francaise avant le 1er juillet 2016. Si cette directive prevoit une surveillance medicale des travailleurs exposes aux champs electromagnetiques, elle ne donne aucune indication pratique au medecin du travail sur la conduite a tenir. Sur quels elements se baser pour se positionner sur le maintien dans l’emploi et/ou l’adaptation du poste de travail ? Les perturbations des implants cardiaques (stimulateurs cardiaques [SC]) ou defibrillateurs automatiques implantes (DAI) par des champs electromagnetiques sont des phenomenes physiques complexes, particulierement pour le cas du champ electrique 50 Hz. Methode Un systeme d’exposition pour tester des implants cardiaques au champ electrique 50 Hz a ete concu pour simuler au mieux les situations reelles. Il comprend un fantome electromagnetique dont les proprietes correspondent a celles du corps humain dans lequel est dispose l’implant a tester. Le dimensionnement du systeme d’exposition a ete determine par simulation theorique de maniere a pouvoir tester des niveaux representatifs de l’exposition professionnelle aux champs electriques 50 Hz, comme dans les postes a tres haute tension. Resultats Les tests ont ete realises sur 14 DAI de 11 modeles differents et 53 SC de 28 modeles differents. Les implants cardiaques etaient programmes en mode AAI/VVI, avec une sensibilite maximale. Les resultats actuellement en cours d’analyse seront presentes et discutes lors du congres. Conclusion Cette etude propose une methode originale pour tester des implants par rapport au risque de perturbation par un champ electrique 50 Hz. Elle permet d’obtenir davantage de donnees pour aider le medecin du travail dans sa decision sur l’aptitude d’un travailleur porteur d’un implant cardiaque. Cette approche est l’une des methodes proposees par la serie de normes EN 50527 pour evaluer le risque pour un travailleur porteur d’implant actif.

Introduction Des etudes recentes ont etablies le seuil de perception des magnetophosphenes aux frequences de 50 et 60 Hz en realisant des expositions de champ magnetique (CM) croissantes de 5000 μT a 50 000 μT chez des volontaires sains. Ce seuil se situe autour de 15 000 μT pour une exposition tete entiere. S’agissant de niveaux de CM particulierement eleves et bien qu’il n’y ait eu aucune manifestation declaree autre que la perception de magnetophosphenes chez les volontaires pendant ces expositions, breves (5 secondes repetees 50 fois) et intenses, ces travaux fournissent l’opportunite de completer l’evaluation biophysique et neurophysiologique avec une evaluation biochimique centree sur les hormones du stress. L’exposition a des niveaux de CM de l’ordre de 1000 μT en expositions aigue ou prolongee chez l’animal en laboratoire et chez l’homme (il s’agit la de niveaux d’exposition professionnelle) n’avait pas montre de variation significative par rapport aux temoins. Les hormones de stress concernees sont essentiellement le cortisol, l’ACTH, les catecholamines et la prolactine qui sont affectees, a des degres variables, par un agent stresseur et sont secretees avec une cinetique de reponse compatible avec les conditions de l’exposition des volontaires. Aucune etude de ce type, avec des niveaux d’exposition aussi eleves, n’a jamais ete conduite chez l’humain. Materiel et methodes Une etude de faisabilite a ete conduite sur 5 volontaires dans le cadre d’une autorisation ethique restreinte. L’exposition a ete realisee au moyen du systeme d’exposition utilise pour l’etude du seuil de perception des magnetophosphenes, certifie « Medical Grade » par la « Canadian Standards association ». Les prelevements sanguins au bout du doigt ont ete effectues sur test HemaSpot ® . Les volontaires ont ete recrutes parmi le personnel du laboratoire. Chaque sujet a ete expose au niveau de la tete entiere pendant 10 minutes a un champ magnetique a 50 000 μT et des prelevements sanguins ont ete realises avec HemaSpost a 4 reprises : 3 minutes avant le debut de l’exposition, puis 2 et 7 minutes apres le debut de l’exposition (donc pendant l’exposition), et enfin 7 minutes apres la fin de l’exposition. L’EEG a ete enregistre et les ondes alpha (8–12 Hz) ont ete analysees au niveau du lobe occipital pour la minute precedant chaque prelevement sanguin. Chaque sujet a egalement complete une session experimentale controle suivant strictement le meme decours temporel mais sans jamais etre expose au CM. Resultats et conclusion Le cortisol et la TSH ont ete doses dans ce premier travail, et l’activite occipitale alpha a ete analysee. Les resultats de cette etude de faisabilite seront presentes lors du congres.

La directive 2013/35/UE du 26 juin 2013, directive particuliere de la directive cadre 89/391/CEE, fixe les prescriptions minimales de securite et de sante relatives a l’exposition des travailleurs aux champs electromagnetiques (CEM). Elle impose une surveillance medicale appropriee de la sante des travailleurs afin de prevenir et de detecter le plus rapidement possible tout effet nocif sanitaire resultant de l’exposition aux champs electromagnetiques. L’article 5, relatif aux dispositions visant a eviter ou a reduire les risques, precise que l’employeur doit mettre a jour, si necessaire, l’evaluation des risques et les mesures preventives lorsque le travailleur signale l’apparition de symptomes passagers. Ceux-ci peuvent inclure « des perceptions sensorielles et des effets sur le fonctionnement du systeme nerveux central dans la tete suscites par des champs magnetiques variant dans le temps ». Cette notion est egalement developpee dans l’article 6 relatif a l’information a donner aux travailleurs sur « la possibilite de symptomes passagers et de sensations lies aux effets sur le systeme nerveux central ou peripherique ». L’article 8, relatif aux mesures de surveillance de la sante, indique lui, que « si tout effet indesirable ou inattendu sur la sante est signale par un travailleur […] l’employeur [doit] veiller a ce que le travailleur concerne puisse beneficier d’examens medicaux ou d’une surveillance medicale appropries, conformement a la legislation et aux pratiques nationales ». Du fait de la vaste etendue des symptomes pouvant etre couverts par les termes de la directive, une des incidences potentielles sur les services de sante au travail est l’eventuel developpement de plaintes liees a l’electrohypersensibilite (EHS), toute « sensation » ou symptome non specifique pouvant etre attribue a une exposition aux CEM sur le systeme nerveux central ou peripherique. L’objectif de cette presentation est de rappeler ce qu’est le syndrome d’electrohypersensibilite (EHS), appele egalement syndrome d’intolerance idiopathique lie aux CEM et les donnees scientifiques associees ainsi que le resultat des expertises collectives recentes. Dans le contexte tres mediatise de l’EHS, il est important que les services de sante au travail aient des connaissances de base pour gerer ce risque.

Although studies have found that extremely low-frequency (ELF, < 300 Hz) magnetic fields (MF) can modulate human standing balance, the acute effects of electromagnetic fields on standing balance have not been systematically investigated. This work aims to establish the threshold for acute standing balance modulation during ELFMF exposure. One hundred volunteers will be exposed to transcranial electric stimulations (Direct Current - DC and Alternating Current - AC, 1 mA) and ELFMF (0 to 160 Hz, 0 to 100 mT). The displacement of their center of pressure will be collected and analyzed as an indicator of vestibular performance. During pilot testing (n=6), we found increased lateral sway with DC, and to a lesser extent, AC exposure. The ELFMF exposure system still needs to be adapted to allow meaningful results. Future protocol design will test for possible effects due to exposures in the radiofrequency range (i.e. above 3 kHz). These results will contribute to the literature documenting exposure guidelines aiming to protect workers and the general public.

The functioning of cardiac implants such as implanted cardiac defibrillator (ICD) may be perturbed by the exposure of the implanted person to electromagnetic field at workplace. We propose a method in order to help the occupational physician to take a decision when assessing the fitness for work in such a case, which is based on in situ assessment studies. We give here examples of exposure to 50 Hz magnetic field and to 380–400 MHz electromagnetic field.

To assess the perception of risk of general practitioners (GPs) about electromagnetic fields (EMF), their sources of information, as well as their patients' level of concern.Six hundred French GPs were selected according to the quotas method. They were asked to answer 24 items via an electronic questionnaire using the Computer-Assisted Web Interviewing (CAWI) method.The GPs know the main EMF sources: cell phone towers, cell phones, power-lines, microwave ovens and WiFi networks. Patients mostly complain or worry about the first three sources and ask their GP for information about these. GPs themselves search for information in the mainstream media rather than in the usual scientific and medical press. As a consequence, their knowledge about potential risks of EMF is deemed rather crude.The GPs are sensitive to environmental concerns, particularly regarding EMF exposure. However, according to the results analysis, they do not have the same approach because of an obvious lack of mastery in a complex and poorly informed situation. A serious educational effort is essential and would be welcomed by practitioners, who are aware of their responsibilities in terms of counseling, diagnosis and care.

Extremely low frequency (ELF) electric and magnetic fields (E&MF) lie between 1 and 300 Hz and form an integral part of the electromagnetic spectrum.

Electromagnetic fields, environment and health / , Electromagnetic fields, environment and health / , کتابخانه دیجیتال جندی شاپور اهواز

This paper presents a numerical modeling study of electromagnetic interference (EMI) in implantable cardioverter-defibrillators (ICDs), exposed to low frequency magnetic fields. Initially, an analysis of the standards that consider interference in ICDs was performed, to determine the level of induced voltage that may occur when the device is exposed to such magnetic fields. A Helmholtz coil was used to generate a uniform magnetic field. The magnetic field exposure was performed for the frontal position (front to back). This position presents the worst case scenario. The induced electric fields and voltage were investigated in both a simple homogenous block (brick) and in an anatomical model (virtual phantom). The ICD's sensitivity parameters were adjusted to minimum values (e.g. 0.2 mV for ventricular detection). This maximum sensitivity corresponds experimentally to the worst-case EMI scenarios. The results showed that magnetic fields above 5000 μT were required for the ICD to possibly present a dysfunction in the homogenous block, while they were only 1400μT in the anatomical model. These results could be informative for any proposed standards concerning the safety of ICDs (CENELEC, INCIRP) for workers as well as for the general public.

L’induction, pour le public, est un nouveau mode de cuisson qui se developpe de plus en plus. Avec une plaque a induction, il y a moins de risques de se bruler apres retrait de l’ustensile, car la surface de la plaque reste presque froide, seulement chauffee par la casserole elle-meme. Les plaques a induction sont tres attractives a plusieurs titres: tout comme le gaz, elles n’ont pas d’inertie thermique et lorsque l’on coupe l’alimentation electrique, la chauffe cesse immediatement. Il n’y a pas d’emission de chaleur ailleurs que dans la casserole, de fait leur rendement energetique, situe entre 80 % et 90 %, est excellent. Le principe de cette technologie est fonde sur les courants de Foucault, qui sont des courants electriques crees dans une masse conductrice soit par la variation au cours du temps d’un champ magnetique exterieur traversant ce milieu, soit par un deplacement de cette masse dans un champ magnetique constant.