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Plastic and rubber based composites containing carbon black (CB) were investigated for the potential to release CB nano-particulates under stress conditions into food simulants. Nanocomposites were exposed to thermal, chemical, and mechanical stress, followed by mechanical abrasion of their surface. Particle sensitive asymmetric flow field-flow fractionation (AF4) with multi angle laser light scattering (MALLS) detection was used to detect and quantify CB nano-particulates. This study demonstrates that, even under dynamic stress conditions, CB nano-particulates are not released from the plastic or rubber compounds into food. This study intends also to propose a general nano-release stress test protocol for plastic materials coming into contact with foodstuff.

In this study, the migration potential of laponite, a small synthetic nanoclay, from nanocomposites into foods was investigated. First, a laponite/ethylene vinyl acetate (EVA) masterbatch was compounded several times and then extruded into thin low-density polyethylene (LDPE) based films. This way, intercalation and partial exfoliation of the smallest type of clay was achieved. Migration of laponite was investigated using Asymmetric Flow Field-Flow Fractionation (AF4) with Multi-Angle Laser Light Scattering (MALLS) detection. A surfactant solution in which laponite dispersion remained stable during migration test conditions was used as alternative food simulant. Sample films with different loadings of laponite were stored for 10 days at 60 &deg, C. No migration of laponite was found at a limit of detection of 22 &micro, g laponite per Kg food. It can be concluded that laponite (representing the worst case for any larger structured type of clay) does not migrate into food once it is incorporated into a polymer matrix.

In this study internal and seam covering coatings as used in food cans were investigated on their potential to release nanomaterials (pigments, fillers) when food is stored and processed (sterilised) within coated cans. Two interior lacquers based on epoxy- and polyester- (with and without bisphenol A) resins and two seam covering coatings were used as lacquer matrices covering typical lacquer formulations. Eight different nanomaterials (four pigments and four fillers) were investigated that are typically used for adjusting colour and enhancing thermal and mechanical stability of the coatings. Aqueous sodium dodecylsulfate surfactant solution showed best suitability to disperse the nanomaterials with sufficient stability. A stable multi-nanomaterial dispersion, containing all eight nanomaterials at the same concentration each, was successfully used to develop an analytical method based on asymmetric flow filed-flow fractionation (AF4) coupled with multi angle laser light scattering (MALLS) detection and inductively coupled plasma mass spectrometry (ICP-MS) that allowed screening for possibly migrating nanomaterials at a limit of detection of 0.5 mg/dm2. Coated metal plates were brought in contact with the aqueous surfactant solution as alternative food simulant for 2 h at 130 °C (sterilisation) followed by for 10 days at 60 °C (long-term storage). Via AF4/MALLS measurements the release of small oligomeric components from internal coating formulations was detected. However, the particle- and element-specific detection system demonstrated the none-migration of nanomaterials (fillers or pigments) from all test samples.

a b s t r a c t An experimental study on the migration into food simulants of TiN nanoparticles (NPs) incorporated at three different levels in low density polyethylene (LDPE) films was carried out under severe test conditions. It was shown that within the analytical sensitivity of the applied ICP-MS method no measurable migration of titanium was found at detection limits to 0.09‐0.11 mg kg � 1 for the food simulants 95% ethanol and iso-octane and 0.24 mg kg � 1 for 3% acetic acid. In addition a migration model generally applicable for nanoparticles was established based on an existing migration model for conventional polymer additives to explore into the migration range below the experimentally accessible detection limits. The modeling results indicate that measurable migration may only occur for NPs up to approximately 3.5 nm in diameter but not for larger ones. Overall, the conclusion was drawn that due to the usual size, shape and aggregation of NPs in plastics nanocomposites nanomaterials are immobilized in food contact plastics. Exposure of the consumer to nanomaterials via migration from food contact plastics cannot be expected.

Background The development of applications using nanomaterials is accompanied by safety concerns due to gaps in understanding the toxicology. In case of incorporation in food contact polymers, the first step to consumer exposure is the transfer of nanomaterials from the polymer to the food. Thus, in order to evaluate the risk the key questions are whether nanoparticles can be released from food contact polymers and under which conditions. Scope and Approach This article critically reviews the published nanomaterial migration studies which are partly contradictory. The influence of analytical techniques and the experimental design on the results are discussed. Theoretical approaches by mathematical modelling are addressed. Furthermore, a short overview on nanomaterial applications for food contact materials and on the regulatory situation in Europe and USA is given. Key findings and conclusions Distinguishing between particle release and migration of dissolved ions is crucial for proper interpretation of migration results. Nanosilver which is the mostly investigated species, and other metals are easily oxidized to ions but can re-form nanoparticles at slightly reductive conditions, e.g. at sample preparation, pretending particle migration. At cutting edges the particles may be released due to weak binding to the surface. Nanoparticles which are completely encapsulated in the host polymer matrix do not have a potential to migrate into food. Thus, consumers will not be exposed to nanoparticles from food contact polymers when those are completely embedded in polymer and the contact surface is not altered by mechanical surface stress during application.

Carbon black was investigated to assess and quantify the possibility that nanoparticles might migrate out of plastic materials used in the food packaging industry. Two types of carbon black were incorporated in low-density polyethylene (LDPE) and polystyrene (PS) at 2.5% and 5.0% loading (w/w), and then subjected to migration studies. The samples were exposed to different food simulants according to European Union Plastics Regulation 10/2011, simulating long-term storage with aqueous and fatty foodstuffs. Asymmetric flow field-flow fractionation (AF4) coupled to a multi-angle laser light-scattering (MALLS) detector was used to separate, characterise and quantify the potential release of nanoparticles. The AF4 method was successful in differentiating carbon black from other matrix components, such as extracted polymer chains, in the migration solution. At a detection limit of 12 µg kg−1, carbon black did not migrate from the packaging material into food simulants. The experimental findings are in agreement with theoretical considerations based on migration modelling. From both the experimental findings and theoretical considerations, it can be concluded that carbon black does not migrate into food once it is incorporated into a plastics food contact material.

A retrospective analysis of H1N1 vaccination in 127 children at ≥ 1 year after liver transplantation found only moderate acceptance (56%) of the vaccination. Physical adverse events were of moderate severity, but frequent (74%). Protection against infection was good, with infection rates of 4% in vaccinated children versus 25% in nonvaccinated children.

Intraoperative radiography based on mobile image intensifier systems (C-arms) is widely used during the treatment of trauma and emergency patients. These devices produce scattered radiation, potential hazardous for surgeon and operation room personal (ORP). The propagation and intensity of scattered radiation is not intuitive, is not perceivable by human senses and depends on many variables. At courses on radiation protection the knowledge of the behavior of scattered radiation and the modus operandi to minimize the radiation exposure should be taught to ORP and surgeons. Currently this can only be done theoretically using fixed pictures and precalculated videos. This paper presents an approach to interactively simulate and visualize scattered radiation with a computer based training system for mobile image intensifier systems. The simulation depicts radiation propagation and intensity for arbitrary C-arm adjustments and different irradiated materials. This teaching component focuses on improving the current radiation protection training with interactive visual and practical aspects.