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The GEOCAP epidemiological study of paediatric cancers in relation with various environmental factors is currently being carried out in France. Proximity to high voltage overhead lines (63–400 kV) related to exposure to extremely low frequency magnetic field (ELF-MF) is one of studied factors. The study covers the mainland French territory and includes 4174 leukaemia cases and 45 000 controls recruited from 2002 to 2010. Residential exposure was calculated for 1124 subjects whose distance to power lines was small enough for their residential exposure to possibly exceed the background reference level 0.1 μT. Residential exposure was calculated by modelling all the influencing spans close to the subjects’ residences. At final, 371 subjects out of 1124 have a calculated exposure over 0.1 μT, including 123 subjects over 0.4 μT, i.e. 0.25% of the study population. These 371 calculated exposures exceeding 0.1 μT have been matched to an existing database of ELF-MF measurements performed in inhabited areas crossed by power lines, and measurements were found for 206 subjects. Comparison was possible for 156 of them. After extrapolation of the measured values to match to calculation conditions, the difference between calculations and adjusted measurements was lower than 30% for 124 subjects (80%), with no clear tendency for over/under estimation. Differences higher than 30% have been analysed and explained.

International audience; The goal of clean renewable energy production has promoted the large-scale deployment of marine renewable energy devices, and their associated submarine cable network. Power cables produce both electric and magnetic fields that raise environmental concerns as many marine organisms have magneto and electroreception abilities used for vital purposes. Magnetic and electric fields’ intensities decrease with distance away from the cable. Accordingly, the benthic and the sedimentary compartments are exposed to the highest field values. Although marine invertebrate species are the major fauna of these potentially exposed areas, they have so far received little attention. We provide extensive background knowledge on natural and anthropogenic marine sources of magnetic and electric fields. We then compile evidence for magneto- and electro-sensitivity in marine invertebrates and further highlight what is currently known about their interactions with artificial sources of magnetic and electric fields. Finally we discuss the main gaps and future challenges that require further investigation.

International audience; We present a new numerical model to calculate the surface deflection of a two-dimensional, yet variable thickness, thin elastic plate. The model is based on a multi-grid, finite difference solution of the fourth-order differential equation that incorporates the terms arising from the non-uniform thickness assumption. The model has been developed to calculate the flexural response of the continental lithosphere subjected to an arbitrary, instantaneous stretching. The flexural model is coupled to (a) a finite element, three dimensional thermal model incorporating the conduction, advection and production terms that allows the computation of the thermal subsidence resulting from the stretching-induced perturbation of the isotherms, assuming that the effective elastic thickness is controlled by the depth to a given isotherm; and (b) a finite difference surface process model that assumes that transport is linearly proportional to slope leading to a second-order, diffusion-type partial differential equation. The model also incorporates the effect of sediment compaction. We present a series of simple benchmarks that demonstrate the accuracy of the model. We also present results of simple 2D and 3D stretching experiments highlighting the importance of 3D flexural effects and the assumed variable elastic thickness on the development of a passive margin and its thermal evolution. Finally, we perform a numerical experiment based on a stretching geometry derived from the present-day geometry of the Western AfricaTransform Margin to predict sediment accumulation patterns and a stratigraphic architecture which we can compare to observations.

International audience; The Namibian margin evolution started 130 Myr ago after the breakup between South America and southern Africa. Today, it shows specific features: (i) an elevation and a bathymetry about 1000 m higher than the surrounding areas, (ii) a significant sediment supply during the Late Cretaceous following the first sedimentary peak that occurred during rifting and just afterwards, and (iii) a long-term progradation since the Mid- Cretaceous. This present configuration results in couplings between several processes and the inherited structure. We constrained this evolution using a numerical simulation applied both onshore and offshore integrating different couplings: i) a thermal adjustment of a lithosphere driven by conductivity, ii) a flexural isostasy, and iii) the loading/unloading effects of surface matter transfer. Three processeswere investigated: rock-uplift, a change in the erosion efficiency and a sea-level fall. The resultswere compared to some pertinent observationsmade on the Namibian margin such as the vertical displacements, the sediment transfers, the denudation and the stratigraphic architecture in the marginal basin. In each simulation, rift-related reliefs were rapidly relaxed resulting in an exponentially decreasing denudation and sediment accumulation. Sixty Myr after the breakup,we simulated an additional uplift, an increase in the transfer efficiency of the sediment and a sea-level fall. The subsidence increased by loading, inducing a new progradational trend. Nonetheless, the three types of events differed in the duration of this progradation trend. The larger the additional uplift, the longer the progradation. The transfer efficiency increase and sea-level fall only resulted in a transient progradation trend. From these results,we suggest that the post-rift evolution of the Namibian margin was associated, during the Upper Cretaceous, to the rejuvenation of its continental relief triggered by a climate change during the Turonian and by a slow long-term rock-uplift during the Cenozoic

An epidemiological study of paediatric cancers in relation with various environmental factors is currently being carried out in France. One of these factors is the proximity of children's residences to high voltage overhead lines (63-400 kV). This possible influence will be studied following three criteria, namely 'distance', 'distance-voltage' and 'calculated residential exposure' to extremely low frequency magnetic field (ELF-MF). This paper describes methods for generating and characterising these three criteria of increasing complexity and characterises the influence of the input data in terms of uncertainties in the exposure to ELF-MF assigned to subjects. The method developed for the 'calculated residential exposure' criterion is based on a limited number of configurations of overhead lines, selected to have a representative sample of the French high voltage (HV) network. The calculated exposure is then fitted to each subject and each neighbouring overhead line, taking into account the yearly mean current flowing in the line and the distance of the residence from the power line. All variability factors introduced by this simplified representation have been analysed, classified and quantified to give the best assessment and associated confidence interval of the residential ELF-MF exposure of the subjects. The overall 1σ uncertainty of the calculated residential exposure excluding geo-coding uncertainties is around 8% for subjects living close to power lines with a known current load and 17% for the others.

Health guidelines for electric and magnetic fields in the low frequency range define exposure limits for electric and magnetic fields in terms of induced electric field in the human body, which is not directly measurable, requiring use of dosimetry. However many parameters, such as human models, calculation codes and post-processing methods influence the calculation results. Based upon many published papers and therefore covering a wide range of these influence parameters, this paper proposes a method for conservatively deriving measurable levels of electric and magnetic fields equivalent to the basic restrictions. Following this method, we found that, regarding exposure to uniform fields, the ICNIRP 2010 occupational basic restrictions are equivalent to a 2 mT and 7 mT magnetic field and to a 35 kV m-1 and 35 kV m-1 electric field at 50 Hz when applied respectively to the central and peripheral nervous system.

The medium-term effects of permanent or random exposure to stray voltage applied to the water trough were evaluated on milk production and stress physiology in lactating dairy cows. Seventy-four Holstein cows were assigned during two 8-wk experimental periods to 1 of 3 treatments. The treatments were permanent exposure to voltage (PERM, 1.8 V, n = 23) applied to the water trough, random exposure to voltage (RAND, 1.8 V, 36 h/wk, n = 25), and no exposure to voltage (control, n = 26). On the first day of voltage exposure, PERM cows had higher activity levels than control cows (9.8 ± 2.70 vs. −2.3 ± 2.74 14-s periods of movement/h). During the eighth week of exposure, RAND cows had higher activity levels than control cows (4.2 ± 3.64 vs. −7.7 ± 3.54 14-s periods of movement/h) and higher milk cortisol concentration than PERM cows (0.21 ± 0.024 vs. 0.14 ± 0.020 ng/mL). No differences were observed between treatments for cortisol response after an ACTH challenge during the seventh week of exposure. No effects of voltage exposure were observed on production traits and daily water intake. There was a transient decrease in milk yield on the second day of exposure in PERM cows (−1.4 ± 0.74 kg) and on the third day of exposure in RAND cows (−3.5 ± 1.03 kg) compared with control cows. In dairy cows, permanent or random exposure to stray voltage (1.8 V; 3.6 mA) could induce a transient stress response. Moreover, unpredictable voltage exposure could be considered a mild stressor, with slight modifications in stress physiology and activity but no impairment in production in the medium term.

Regulatory compliance of electrical equipment in livestock farms. The safety of electrical installations is a necessity in professional and domestic environments. In livestock housing, regulatory compliance is the essential condition to ensure that people and animals are not exposed to the adverse effects of electrical currents circulating outside the conductors of the distribution circuit and connected devices. If electrical installations are badly designed, too old, or altered by aggressive ambient conditions (humidity, animal dejections, etc.), abnormal voltage may occur on metal components (sliding feeding racks, drinking troughs…). When the animals come in contact with these objects, electrisation occurs with the risk of adverse effects. Preventing such stray voltage and currents is based on the compliance with the basic rules of electrical safety, involving the presence of an earth-leak circuit breaker, connection of all metal masses between themselves to ensure they are always at the same potential, and their connection to an adequate earth system., La sécurité des installations électriques est une nécessité dans les milieux professionnels et domestiques. Dans les bâtiments d’élevage, le respect de la réglementation est la condition indispensable pour éviter que les hommes et les animaux puissent être exposés aux effets défavorables de courants électriques circulant en dehors des conducteurs du circuit de distribution ou des appareils qui lui sont reliés. En raison de défauts de conception des installations ou d’altérations résultant de leur vétusté, voire de leur dégradation par les conditions agressives du milieu (humidité, déjections, etc..), des tensions anormales peuvent exister sur des éléments métalliques de l’élevage (cornadis, abreuvoirs…). Lorsque les animaux entrent en contact avec ces objets, ils sont traversés par des courants susceptibles de produire des réactions défavorables. La prévention de ces tensions et courants parasites repose sur le respect des dispositions de base de la sécurité électrique que sont la présence d’un disjoncteur différentiel, la connexion de toutes les masses métalliques entre elles, assurant que toutes sont toujours au même potentiel, et leur liaison à une prise de terre correctement établie., Deschamps François. La conformité réglementaire des installations électriques des élevages. In: Bulletin de l'Académie Vétérinaire de France tome 163 n°3, 2010. pp. 235-241.

Introduction La Directive europeenne 2013/35/UE, dont l’objectif est de prevenir les risques pour les travailleurs dus a l’exposition aux champs electromagnetiques, definit des valeurs limites d’exposition (VLE) qui ne sont pas mesurables. En effet, ces VLE sont definies a l’interieur du corps humain, et ne peuvent donc etre verifiees que par des calculs electromagnetiques complexes. La Directive definit egalement des valeurs declenchant l’action (VA) qui sont mesurables, mais prevoit la possibilite que le travailleur soit expose au-dessus de ces VA, a condition que les VLE soient respectees. Afin que le medecin du travail et l’ensemble des preventeurs puissent facilement verifier la conformite des situations de travail a cette VLE, il est necessaire de les convertir en valeurs mesurables. Methode Un certain nombre d’etudes calculant les phenomenes induits par les champs electromagnetiques dans le corps humain ont ete publiees depuis les annees 1980. Une revue de la litterature a ete menee, en selectionnant tous les articles pouvant etre utilises dans le contexte des lignes directrices publiees par l’ICNIRP en 2010, et qui sont la base scientifique de la directive, c’est-a-dire les articles utilisant des modeles de corps humain anatomiquement realistes et presentant des resultats en termes de champ electrique induit. Seules les situations d’exposition a des champs uniformes ont ete considerees, afin de garantir une approche conservative. La comparaison des resultats des differents articles nous a permis d’evaluer les composantes d’incertitudes de ces calculs. Les valeurs mesurables correspondant aux VLE sont alors derivees a partir d’un calcul de reference, et en ajoutant les incertitudes quantifiees. Resultats Les principaux parametres d’influence sont la methode de calcul, la taille du maillage utilise pour ce calcul, la conductivite des tissus, la morphologie du corps humain et le post-traitement des resultats. Suivant la methode proposee, la VLE relative aux effets sensoriels correspond, a 50 Hz, a un champ magnetique de 2 mT et a un champ electrique de 35 kV/m. La VLE relative aux effets sur la sante correspond, a 50 Hz, a un champ magnetique de 7 mT et a un champ electrique de 35 kV/m. Conclusion La methode proposee est basee sur une revue de la litterature scientifique concernant les calculs de couplage entre corps humain et champ electrique ou magnetique 50 Hz, et couvre donc un large ensemble des parametres d’influence de ces calculs. Elle permet de deriver a partir des VLE, de maniere conservative, des valeurs de champ electrique ou magnetique mesurables au poste de travail. Ces valeurs plus facilement utilisables pour mettre en place des actions de prevention.

Plastics are generally mixed with additives like plasticizers to enhance their flexibility, pliability, and elasticity proprieties. Plasticizers are easily released into the environment and are absorbed mainly through ingestion, dermal contact, and inhalation. One of the main classes of plasticizers, phthalates, has been associated with endocrine and reproductive diseases. In 2002, 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH) was introduced in the market for use in plastic materials and articles intended to come into contact with food, and it received final approval from the European Food Safety Authority in 2006. At present, there is limited knowledge about the safety and potential metabolic and endocrine-disrupting properties of DINCH and its metabolites. The purpose of this study was to evaluate the biological effects of DINCH and its active metabolites, cyclohexane-1,2-dicarboxylic acid (CHDA) and cyclohexane-1,2-dicarboxylic acid mono isononyl ester (MINCH), on rat primary stromal vascular fraction (SVF) of adipose tissue. DINCH and its metabolite, CHDA, were not able to directly affect SVF differentiation. However, exposure of SVF to 50 μM and 100 μM concentrations of MINCH affected the expression of Cebpa and Fabp4, thus inducing SVF preadipocytes to accumulate lipids and fully differentiate into mature adipocytes. The effect of MINCH was blocked by the specific peroxisome proliferator-activated receptor (PPAR)-α antagonist, GW6471. Taken together, these results suggest that MINCH is a potent PPAR-α agonist and a metabolic disruptor, capable of inducing SVF preadipocyte differentiation, that may interfere with the endocrine system in mammals.

The affinity and specificity of 17α-ethynylestradiol (EE) molecularly imprinted polymers (MIPs), prepared with methacrylic acid or vinylpyridine (VP) in toluene or methylene chloride, were evaluated by radioassay. Proton NMR model studies into complex formation between the template and functional monomer analogues, acetic acid and deuterated pyridine were performed in the same solvents that were used as porogens for the MIP. A correlation was found to exist between the binding strength and specificity of a particular polymer and the extent of complex formation shown by the corresponding NMR spectrum.

International audience; Passive margins display various structural and morphological patterns resulting in a complex coupling between local effects.We performed an integrated analysis from the ocean to the continent at the crustal scale of the post-breakup evolution of the northern Namibian margin in terms of vertical displacements and palaeotopography. A main topographic scarp that disappears where the Palaeo-Proterozoic Damara belt crosses the coast separates the Namibian margin and the South African plateau.We analysed this transition using a synthetic crustal cross-section based on a compilation of published data as well as new field data. The thinned margin displays two domains separated by a deep sedimentary trough. This trough separates a proximal part with landward tilted blocks from the distal part with seaward tilted blocks. This structural pattern reveals a complex flowing pattern of the ductile crust controlled by magmatism. Onshore, the basalts and Cenozoic conglomerates recorded a progressive seaward tilting of the coastal zone. Post-breakup vertical motions were estimated with subsidence curves in the offshore domain and from isostatic adjustments induced by the variations of cover thickness (depth of magmatic intrusions and Apatite Fission Tracks) in onshore domain. Three domains are recognised: a subsiding offshore domain, a uplifting continental domain and a transitional domain, located on both sides of the current shoreline with successive phases of uplift and subsidence. The offshore subsidence displays variations along the margin controlled by the thinning crust generated by the continental breakup. The onshore palaeotopogaphy is approximately assessed since the end of rifting by integrating the isostatic adjustment induced by denudation: the mean elevation of the plateau has remained above 1000 m since continental breakup. No significant additional uplift was pointed out during the late Cretaceous or late Neogene. Therefore, we conclude that the South African plateau has been present in northern Namibia since 130 Ma, at least

Consequences of low electrical currents on the welfare of dairy cattle. Emphasis on individual variability When heifers were exposed to an electrical current which voltage was increased daily, a short-term persistent reaction threshold of 2.3 V (3.5 mA) was observed, despite a large individual variability. In the medium-term, a multi-criteria experimental approach in dairy cows exposed to a permanent (predictable) or random (unpredictable) voltage of 1.8 V (3.6 mA) on the water trough showed no modification of the amount and composition of milk, although a transient acute stress response was observed. Cows exposed permanently to the voltage became habituated to it, whereas those exposed unpredictably may have shown signs of a mild chronic stress. The individual variability of the cow resistance could explain the differences in behavioural responses. In farms, it is important to reduce the presence of stray voltage, even of low level, as they may affect animal welfare., Lors de l’application d’une tension électrique augmentée progressivement chaque jour, un seuil de réaction persistante de 2,3 V (3,5 mA) a été mis en évidence à court terme chez des génisses, malgré une forte variabilité individuelle. À moyen terme, une analyse multicritère a montré que l’exposition de vaches laitières, de manière permanente (prévisible) ou aléatoire (imprévisible), à une tension de 1,8 V (3,6 mA) au niveau de l’abreuvoir n’a pas modifié la quantité de lait produite ni sa composition, bien qu’une réponse de stress aigu transitoire ait été observée. Les vaches exposées de manière permanente se sont habituées, contrairement aux vaches exposées de manière imprévisible chez lesquelles la présence d’un stress chronique modéré est envisagée. La variabilité individuelle de résistance des vaches pourrait expliquer la variabilité des réponses comportementales. En élevage, il est important de limiter la présence de tensions parasites, même de faible niveau, qui pourraient perturber le bien-être des animaux., Rigalma Karim, Roussel Sabine, Deschamps François, Duvaux-Ponter Christine. Conséquences de faibles courants électriques sur le bien-être de bovins laitiers. Prise en compte de la variabilité individuelle. In: Bulletin de l'Académie Vétérinaire de France tome 163 n°3, 2010. pp. 251-255.

The effects of permanent or random exposure to stray voltage on a water trough were evaluated in growing–finishing Romane male lambs between the age of 13 and 19 weeks. Ninety lambs were assigned during two 6-week experimental periods to one of three treatments, with 30 animals in each treatment (15 per experimental period). The treatments were permanent exposure to voltage (PERM, 3.5 V) on the water trough, random exposure to voltage (RAND, 3.5 V, 34 h/week) and no voltage exposure for the control group (CONT). No effects of voltage exposure were observed on production parameters: growth, average daily gain and water intake. The stress physiology seemed to be slightly modified with a lower plasma cortisol concentration at slaughter in PERM lambs compared to CONT lambs (P < 0.05) and a higher adrenal medulla weight in PERM lambs compared to CONT lambs (P < 0.05). However, no differences were observed between treatments in heart-rate, basal plasma cortisol concentration and tyrosine hydroxylase and phenylethanolamine-Nmethyl transferase activities. Carcass yield, temperature and the pH of the M. longissimus dorsi were not modified by voltage exposure during rearing. In the good carcass conformation class (R class in EUROP grading scheme), there were fewer fat carcasses (grade 4 of 5) in the PERM and RAND compared to the CONT group (P < 0.05). In conclusion, no major effects of voltage exposure were observed in male lambs on production, carcass parameters and stress physiology. Stray voltage could be considered as a mild stressor in growing–finishing lambs.

Early life-stage survival, motility, and growth toxicity tests were carried out on common carp (Cyprinus carpio L.) endotrophic embryo, with two reference molecules (captafol and DNOC), from fertilization to the end of the first two-thirds period of mortalities by starvation. Thirteen days duration exposure was performed in daily renewed medium, at 24.5°C, in standard synthetic water, at three pHs (6.9, 7.8, 9.0), in the presence of 10 mM/liter nontoxic pH buffer. Nominal concentrations of toxicants were 0.0, 0.25, 0.5, 1.0, and 2.0 mg/liter. Toxic effects on survival, motility, and growth decreased with increasing pH. From pH 6.9 to 9.0, the "no-observed-effect concentrations" differed by a factor greater than 8. Motility and growth cannot be considered, at population level, as true sublethal embryo-larval toxicity criteria. The toxicological interpretation of these results is discussed. They confirm the need of multifactorial methods for toxic risks and effects assessment on fish early life stages in the environment.

Industrial practices in the past have left a fairly large number of sites where the soil may be higly contaminated by chemicals dangerous for men or for ecosystems, either directly, or through their transport to ground waters.

Les idees etant de libre parcours, les diffuseurs et autres producteurs ne peuvent pas proteger, au titre de la propriete intellectuelle, les concepts de leurs emissions. Le droit des marques, le droit d’auteur et la concurrence deloyale leur permettent cependant de proteger de maniere assez satisfaisante les investissements consacres a la creation. On constate ainsi depuis quelques annees une inflation des depots de marque pour les titres d’emission ou meme les slogans ou expressions utilisees par les personnages les plus mediatiques des programmes. A l’origine de ce mouvement, il y a une double volonte : se proteger de ses concurrents et identifier clairement sa creation a l’encontre des autres diffuseurs, mais aussi eviter que des tiers d’autres secteurs du commerce et de l’industrie n’abusent du succes de certains de leurs programmes.