Technical Comments
SML 6 Software – General Presentation
Employing advanced numerical algorithms, migration modelling with the SML software [1] allows prediction of the amount of organic migrant (like residual monomers, additives, contaminants, reaction products, non-intentionally added substances from plastic multi-layer or multi-material multi-layer materials) which migrate into the packed food or other contact media like pharmaceuticals, cosmetics, drinking water or environment. The application of the software insures the compliance of plastic food contact materials and articles with specific migration limits according to EU Regulations [2, 3] and Swiss Legislation [4] …
Probabilistic migration modelling focused on functional barrier efficiency and low migration concepts in support of risk assessment
Migration modelling provides reliable migration estimates from food-contact materials (FCM) to food or food simulants based on mass-transfer parameters like diffusion and partition coefficients related to individual materials. In most cases, mass-transfer parameters are not readily available from the literature and for this reason are estimated with a given uncertainty. Historically, uncertainty was accounted for by introducing upper limit concepts first, turning out to be of limited applicability due to highly overestimated migration results …
Mathematical Modeling of the Extractables Release from Multi-Layered Plastic Films used in Drug Product Containers
The release of extractables from multi-layered plastic films such as those used in containers for liquid drug products has been investigated. Targeted extractables were chosen from the film’s extractable profile, as elucidated by a controlled extraction study. The total available pool of targeted extractables was ascertained via exhaustive sequential extraction of the film and the film layer responsible for the target extractables was established. This information, along with the film’s structure, was used to produce a mathematical migration model for each of these targets …
Migration of antimony from PET trays into food simulant and food: determination of Arrhenius parameters and comparison of predicted and measured migration data
Migration experiments with small sheets cut out from ovenable PET trays were performed in two-sided contact with 3% acetic acid as food simulant at various temperatures. The fraction of diffusible antimony (Sb) was estimated to be 62% in the PET sample under study. Apparent diffusion coefficients of Sb in PET trays were determined experimentally. Measurement of migration between 20 and 150°C yielded a linear Arrhenius plot over a wide temperature range from which the activation energy (Ea) of 188 ± 36 kJ mol-1and the pre-exponential factor (D0) of 3.6 x 1014 cm2s-1 were determined for diffusing Sb species …
Simulation of Deterrent Diffusion in Double Base Propellant Under Different Temperature Profiles
Propellants can burn so rapidly that the initial rise of pressure in weapons may be faster than desired. To avoid this unwanted effect, burning rate of the propellants is moderated by applying a surface coating. Coating agents are usually deterrents (moderants), substances that gelatinize or plasticise the nitrocellulose matrix of the propellants decreasing its initial burning rate, therefore, in turn, the rate of gaseous phase formation. The knowledge of the diffusion rate of deterrents helps therefore in developing propellants with superior ballistic performance …
Leitlinie zur mathematischen Abschätzung der Migration von Einzelstoffen aus organischen Materialien in das Trinkwasser
Die mathematische Abschätzung der Migration kann verwendet werden, um die Anforderungen der KTW-Leitlinie, Beschichtungsleitlinie oder der Schmierstoffleitlinie an die Migration von Einzelstoffen anstelle eines experimentellen Nachweises zu überprüfen. Organische Materialien – zum Beispiel Kunststoffe –, die Kontakt mit Trinkwasser haben, können Stoffe an das Wasser abgeben (Stoffübergang oder Migration). Dabei sinkt die Konzentration der Stoffe in dem organischen Material und nimmt im Wasser zu (Stofftransport) …
Food Contact Materials Compliance Database
Risk assessment and management tool
Guideline for the Mathematical Estimate of the Migration of Individual Substances from Organic Material in Drinking Water
The mathematical estimate of migration can be used in place of experimental proof to verify the requirements of KTW, Coating or Lubricant Guidelines for the migration of individual substances.
Organic material, such as plastics, which comes into contact with drinking water, can release substances into the water (mass transfer or migration). This lowers the concentration of substances in the organic material and increases it in water (mass transport). The stage that determines the speed of the mass transfer is the diffusion of the substance in organic material …
Diffusion Coefficients of Antimony Catalyst in Polyethylene Therephthalate (PET) materials
Antimony trioxide is extensively used by the polymer industry as a polycondensation catalyst in the production of PET. Consequently, contamination of food by antimony from PET packaging has raised concerns about consumer safety. Unfortunately the lack of data on diffusion characteristics of antimony compounds used in the production of PET makes the simulation of migration and the assessment of the risk difficult. A method to assess the migration from PET trays for heating of ready meals into food simulant (3% acetic acid) over a wide temperature range (45 to 150°C) is presented …
Application of Finite Element Analysis (FEA) for the simulation of release of additives from multilayer polymeric packaging structures
Computer programmes are available to predict, for consumer protection purposes, the migration of additives from a polymeric package during its contact with food. However most of these programs were developed to estimate migration only from single layer polymeric packaging under isothermal conditions. In this work a diffusion model was developed to simulate the migration from multilayer packaging and under non-isothermal temperature conditions, too. Finite Element Analysis (FEA) is used as a numerical approximation method to solve the diffusion equations describing such processes …