Effect of the Nature and Concentration of Phthalates on Their Migration from PVC Materials Under Dynamic Simulated Conditions of Mouthing

Polyvinylchloride (PVC) has been a very common material for the production of toys. It generally is manufactured with an addition of additives such as plasticisers to improve its functionality and facilitate its production process. PVC that can contain up to 50% by weight of plasticisers (Simoneau et al., 2001). Among plasticisers, 90% of the most commonly used to soften polymers for toys production are constituted by phthalates, such as diisononyl phthalate (DINP). The purpose of this study was to investigate the influence of the relative concentration of percentage of phthalates and nature of phthalates on their release in standard conditions. To obtain a suitable but rapid method of analysis, experiments were performed to study the effects on the modification of a standard operation procedure (SOP) previously validated at the EU level by JRC Ispra. A single extraction with a sufficient large volume of cyclohexane thus could be used instead of two extractions with a smaller volume of cyclohexane and resulted in more rapid yet reliable method. The final method is described in Annex 1 of this report. Samples of soft PVC were industrially produced especially for this study. Standard PVC disks with various percentages of di-isononyl phthalate (DINP), di-isodecyl phthalate (DIDP), di-ethyl-hexyll phthalate (DEHP), benzylbutyl phthalate (BBP) dibutylphthalate (DBP) or a binary mixture DINP/DBP in various proportions were prepared. 30 different types of disk were produced and tested. The disks were analysed for contents, homogeneity and sets were subjected to migration experiments of the various phthalates under dynamic conditions using the previously validated SOP with some modifications. The release from samples with a systematic manufacturing process and containing different phthalates at different concentrations showed correlations to their concentrations. Since previous studies using commercial toys had no showed such specific trends, these results suggest that the production process of toys may be an important issue with respect to release properties. The release of DEHP BBP and DBP tended to show a more linear correlation to the concentration, whereas for DINP, DIDP, DEHP and release the plasticiser showed non linear tendencies and saturation of release for high formulation contents.JRC.I.2-Chemical assessment and testin

Suitability of new sources of olive oil intended to be used as simulant D in migration testing

Regulation EC/882/2004 on Feed and Food Controls establishes the JRC as Community Reference Laboratory for Food Contact Materials (CRL-FCM). The Regulation requires a supporting network of European National Reference Laboratories (NRLs). This Regulation supports the harmonised enforcement of food legislation including food contact materials and the creation of a reference laboratory system operated by the JRC to systematically exchange and assess information on emerging issues related to chemicals released from food contact materials. The Council Directive 85/572/EEC of 19 December 1985 lays down the list of simulants for overall and specific migration testing, to be used for testing migration of constituents of plastic materials and articles intended to come into contact with foodstuff. This Directive lists the appropriate simulants to be used in migration tests with a particular foodstuff or group of foodstuffs. Within simulants, simulant D is rectified olive oil that has to satisfy characteristics such as acidity, peroxide index, iodine index, refractive index. Until 2005 rectified olive oil with documented appropriate technical specifications was commercially available from the company Pira International (UK). However commercial production stopped, and other potential sources available (Korea Japan, Sigma) did not necessarily provide specifications documented specifically for use as ¿simulant D¿. Since the oil specifications set in the EU legislation are crucial, both for compliance testing but also in the frame of an ISO accreditation for migration in oil, NRLs suggested the CRL-FCM to investigate specifications potential sources of olive oil to develop a source of simulant D for their purposes. The purpose of this study was to: ¿ Find potential suppliers for rectified olive oil ¿ Evaluate characteristics of oil on batch samples ¿ Select one supplier to purchase a lot of adequate defined specifications ¿ Establish the adequacy and homogeneity of the oil of a 500L lot ¿ Confirm the evaluation by independent analyses and certification by a specialised accredited institution for those specifications. The results demonstrated the feasibility of at least one source of olive oil, which was then provided to the National Reference Laboratories as a deliverable of the workprogramme 2007.JRC.I.5-Physical and chemical exposure

Percolation dans des réseaux réalistes de nanostructures de carbone

RÉSUMÉ: Les nanotubes de carbone ont des propriétés mécaniques et électriques très intéressantes pour plusieurs applications en électronique. Ils sont très résistants à la déformation et peuvent être d'excellents conducteurs ou semi-conducteurs. Toutefois, manipuler les nanotubes individuellement pour construire des dispositifs structurés demeure très difficile. Il n'existe pas encore de méthode permettant de contrôler à la fois les propriétés électriques, l'orientation et le positionnement spatial d'un ensemble de nanotubes. Produire des réseaux désordonnés de nanotubes est par contre beaucoup plus facile, et ces systèmes possèdent de plus une bonne conductivité électrique qui les rend très intéressants, notamment comme matériaux d'électrodes transparentes et flexibles. Il y a trois principales méthodes de fabrication employées pour produire des réseaux de nanotubes : le dépôt de solution, la croissance sur substrat et l'enchâssement dans une matrice de polymères. Le dépôt de solution peut engendrer des réseaux de densités diverses sur une variété de substrats. La croissance directe sur substrat permet quant à elle de produire des réseaux très propres sur des substrats tels le SiO2. De son côté, l'enchâssement dans une matrice de polymères permet de produire des volumes composites contenant des quantités variables de nanotubes. Beaucoup de paramètres comme la longueur des tubes, leur orientation ou leur tortuosité influencent cependant les propriétés de ces réseaux et la présence de désordre structural complique la compréhension de leurs interactions. Prévoir les propriétés d'un réseau comme la conductivité à partir de quelques caractéristiques comme la taille des tubes et leur densité peut être difficile. Cette tâche devient d'autant plus complexe si l'on veut maintenant identifier les paramètres qui vont permettre d'optimiser les performances d'un dispositif contenant ce matériau. Nous avons choisi d'aborder le problème des réseaux de nanotubes de carbone en développant une série d'outils numériques qui sont principalement basés sur la méthode Monte-Carlo. Nous tenons compte d'un grand nombre de paramètres pour décrire les caractéristiques des réseaux, ce qui nous permet une représentation plus fiable de réseaux réels ainsi qu'une grande polyvalence pour le choix des constituants des réseaux pouvant être simulés. Les outils que nous avons développés, regroupés dans le logiciel RPH-HPN pour Réseaux percolatifs hybrides - Hybrid Percolation Networks, permettent la construction des réseaux aléatoires, détectent les contacts entre les tubes, traduisent les systèmes en circuits électriques équivalents et calculent les propriétés globales. ABSTRACT: Carbon nanotubes have very interesting mechanical and electrical properties for various applications in electronics. They are highly resistant to deformation and can be excellent conductors or semiconductors. However, manipulating individual nanotubes to build structured devices remains very difficult. There is no method for controlling all of the electrical properties, the orientation and the spatial positioning of a large number of nanotubes. The fabrication of disordered networks of nanotubes is much easier, and these systems have a good electrical conductivity which makes them very interesting, especially as materials of transparent and flexible electrodes. There are three main methods of production used to make networks of nanotubes: the solution deposition, the direct growth on substrate and the embedding in a polymer matrix. The solution deposition method can form networks of various densities on a variety of substrates, the direct growth of nanotubes allows the creation of very clean networks on substrates such as SiO2, and the embedding in a polymer matrix can give composite volumes containing varying amounts of nanotubes. Many parameters such as the length of the tubes, their orientation or their tortuosity influence the properties of these networks and the presence of structural disorder complicates the understanding of their interactions. Predicting the properties of a network, such as conductivity, from a few characteristics such as size and density of the tubes can be difficult. This task becomes even more complex if one wants to identify the parameters that will optimize the performance of a device containing the material. We chose to address the carbon nanotube networks problem by developing a series of computer simulation tools that are mainly based on the Monte Carlo method. We take into account a large number of parameters to describe the characteristics of the networks, which allows for a more reliable representation of real networks as well as versatility in the choice of network components that can be simulated. The tools we have developed, grouped together in the RPH-HPN software Réseaux percolatifs hybrides - Hybrid Percolation Networks, construct random networks, detect contact between the tubes, translate the systems to equivalent electrical circuits and calculate global properties. An infinity of networks can have the same basic characteristics (size, diameter, etc.) and therefore the properties of a particular random network are not necessarily representative of the average properties of all networks. To obtain those general properties, we simulate a large number of random networks with the same basic characteristics and the average of the quantities is determined

Small critical RNAs in the scrapie agent

Unconventional infectious agents cause transmissible spongiform encephalopathy (TSE) diseases including scrapie and bovine spongiform encephalopathy (BSE) in animals and Creutzfeldt-Jakob disease in humans. The protein only hypothesis claims that the TSE agent is composed solely of the protein called prion (PrP^sc^)^1^. This protein is the misfolded form of a host-encoded cellular protein, PrP^c^ exerting presumably a vital role at the synapse^2^. Even though now widely accepted, the prion concept fails to provide in certain circumstances^3-6^, a satisfying interpretation of the infectious phenomenon. Using the 263K scrapie-hamster model, we conducted a transmission study to search for a putative prion-associated factor indispensable for infectivity. Here we show that innocuous recombinant prion protein (recPrP) was capable, in a reproducible manner, of transmitting scrapie disease when the protein was [beta]–sheet converted in a solution containing PrP^sc^-derived RNA material. Analysis of the PrP-RNA mixture revealed the association of recPrP with two prominent populations of small RNA molecules having an average length of about ~27 and ~55 nucleotides. We conclude that the nature of the TSE agent seems to be composed of a nucleoprotein molecular complex, in which informative RNA molecules of small sizes are associated with the misfolded prion protein (PrP^sc^)

Two Neural Circuits to Point Towards Home Position After Passive Body Displacements

International audienceA challenge in motor control research is to understand the mechanisms underlying the transformation of sensory information into arm motor commands. Here, we investigated these transformation mechanisms for movements whose targets were defined by information issued from body rotations in the dark (i.e., idiothetic information). Immediately after being rotated, participants reproduced the amplitude of their perceived rotation using their arm (Experiment 1). The cortical activation during movement planning was analyzed using electroencephalography and source analyses. Task-related activities were found in regions of interest (ROIs) located in the prefrontal cortex (PFC), dorsal premotor cortex, dorsal region of the anterior cingulate cortex (ACC) and the sensorimotor cortex. Importantly, critical regions for the cognitive encoding of space did not show significant task-related activities. These results suggest that arm movements were planned using a sensorimotor-type of spatial representation. However, when a 8 s delay was introduced between body rotation and the arm movement (Experiment 2), we found that areas involved in the cognitive encoding of space [e.g., ventral premotor cortex (vPM), rostral ACC, inferior and superior posterior parietal cortex (PPC)] showed task-related activities. Overall, our results suggest that the use of a cognitive-type of representation for planning arm movement after body motion is necessary when relevant spatial information must be stored before triggering the movement

Report of the interlaboratory comparison organized by the Community Reference Laboratory Food Contact Material: Plasticisers in Gaskets and Oil

The Institute for Health and Consumer Protection (IHCP) of the European Commission¿s Directorate-General Joint Research Centre hosts the Community Reference Laboratory for Food Contact Materials (CRL-FCM). One of its core tasks is to organize interlaboratory comparisons (ILCs) among appointed National Reference Laboratories (NRLs). This report presents the results of the first ILC of the CRL-FCM which focused on the determination of Plasticisers content in PVC Gasket and in Oil matrix. The test materials used in this exercise were virgin gasket lids coming from industrial sources for the proficiency exercise part A. For the second part of the exercise an industrial source of sunflower oil was used and spiked with several plasticisers by the CRL-FCM. There were 41 participants to whom samples were dispatched 34 of which submitted results for at least 1 analyte-material. 21 laboratories reported results for more than 10 analyte-material combination out of 14 required. The homogeneity studies were performed by the CRL-FCM laboratory. The assigned value and its uncertainty for part A, virgin gaskets, were obtained after applying the robust statistics to the results obtained from the participants. The assigned values for part B, oil samples, were those obtained based on formulation, from the gravimetric measurements used to spike the material. The uncertainty of the assigned values for oil samples was calculated combining the uncertainty of the spiking procedure with a contribution for the between-bottle homogeneity. Participants were invited to report four replicates measurements. This was done by most of the participants. Laboratory results were rated with z and z¿ scores in accordance with ISO 13528 [1] Standard deviations for proficiency assessment (also called target standard deviations) were set based on Horwitz equation for substances in the two oil samples. For the plasticisers in the two gasket samples the target standard deviation was set by the organizers to 15% in order to fulfil the required criteria for sufficient homogeneity of the sample within the lots.JRC.I.2-Chemical assessment and testin

Distribution of large-spored Alternaria species associated with early blight of potato and tomato in Algeria

Potato and tomato are important crops in Algerian agriculture, and both are threatened by abiotic and biotic stresses, and early blight is a major disease affecting both crops. Surveys carried out from 2012 to 2015 in 12 major growing regions for these crops yielded a total of 247 Alternaria isolates having morphological and cultural characteristics of sections Alternaria and Porri. Since early blight symptoms and morphological characteristics of the isolates did not allow sharp distinction between the different large-spored species of Alternaria, the isolates in section Porri, often considered primary causes of the diseases, were selected for molecular characterization by diagnostic PCR using specific primers. This allowed species identification of 147 Alternaria isolates as A. solani, A. protenta, A. grandis or A. linariae. These species were present on potato and tomato crops at varying frequencies, depending on the hosts and on bioclimatic locations. Pathogenicity tests for the four species, on detached leaflets and whole seedlings, showed that all were pathogenic to potato and tomato, with varying virulence. These results suggest that parasitic specialization of these Alternaria species on solanaceous plants should be reconsidered

Cavitation Erosion Prediction on Francis Turbines Part 3 : Methodologies of Prediction

In the frame of a joint research program between EDF, Hydro Québec and IMHEF, different methods are investigated to predict cavitation erosion on Francis turbines from model. They are based on measurement of pitting, pressure fluctuations and acceleration. The measurement techniques have been detailed in Part I and Part 2. The present article describes essentially the theoretical and practical aspects of the methods and discusses the results obtained until now from the mode! and prototype tests. The first analysis shows that the methods proposed are suitable to measure cavitation aggressiveness on mode! and on prototype, and that the level on the mode! is several orders of magnitude smaller than on the prototype. To adjust transposition laws, a more complete set of data is needed

Efficacy of tigecycline for the treatment of complicated intraabdominal infections in real-life clinical practice from five european observational studies

Objectives: Tigecycline is a broad-spectrum antibiotic approved for the treatment of complicated intra-abdominal infections (cIAIs). The efficacy of tigecycline when administered as monotherapy or in combination with other antibacterials in the treatment of cIAIs in routine clinical practice is described. Patients and methods: Individual patient-level data were pooled from five European observational studies (July 2006 to October 2011). Results: A total of 785 cIAI patients who received tigecycline were included (mean age 63.1+14.0 years). Of these, 56.6% were in intensive care units, 65.6% acquired their infection in hospital, 88.1% had at least one comorbidity and 65.7% had secondary peritonitis. The mean Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores at the beginning of treatment were 16.9+7.6 (n=614) and 7.0+4.2 (n=108), respectively, indicating high disease severity. Escherichia coli (41.8%), Enterococcus faecium (40.1%) and Enterococcus faecalis (21.1%) were the most frequently isolated pathogens; 49.1% of infections were polymicrobial and 17.5% were due to resistant pathogens. Overall, 54.8% (n=430) received tigecycline as monotherapy and 45.2% (n=355) as combination therapy for a mean duration of 10.6 days. Clinical response rates at the end of treatment were 77.4% for all patients (567/733), 80.6% for patients who received tigecycline as monotherapy (329/408), 75.2% for patients with a nosocomial infection (354/471), 75.8% for patients with an APACHE II score .15 (250/330) and 54.2% (32/59) for patients with a SOFA score =7. Conclusions: In these real-life studies, tigecycline, alone and in combination, achieved favourable clinical response rates in patients with cIAI with a high severity of illness