Materials and articles intended to come into contact with food must be shown to be safe because they might interact with food during processing, storage and the transportation of foodstuffs. Framework Directive 89/109/EEC and its related specific Directives provide this safety basis for the protection of the consumer against inadmissible chemical contamination from food-contact materials. Recently, the European Commission charged an international group of experts to demonstrate that migration modelling can be regarded as a valid and reliable tool to calculate ‘reasonable worst-case’ migration rates from the most important food-contact plastics into the European Union official food simulants. The paper summarizes the main steps followed to build up and validate a migration estimation model that can be used, for a series of plastic food-contact materials and migrants, for regulatory purposes. Analytical solutions of the diffusion equation in conjunction with an ‘upper limit’ equation for the migrant diffusion coefficient, DP, and the use of ‘worst case’ partitioning coefficients KP,F were used in the migration model. The results obtained were then validated, at a confidence level of 95%, by comparison with the available experimental evidence. The successful accomplishment of the goals of this project is reflected by the fact that in Directive 2002/72/EC, the European Commission included the mathematical modelling as an alternative tool to determine migration rates for compliance purposes.
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
19 November 2018 in Food Additives & Contaminants: Part A
Microplastics have been ubiquitously found and identified in aquatic and terrestrial environments for several years. Due to their occurrence in the oceans, microplastics were also found and characterised in seafood products and in other foods and beverages such as beer, honey and table salt. Very recently, microplastic particles were also determined in bottled mineral water. The objective of this publication is to present and discuss a compilation of the currently available literature data on microplastics in bottled mineral water. The related oral exposure of the consumer from substances present in microplastics and from the plastics particles themselves is estimated and toxicological arguments for and considerations on risk assessment from the consumption of bottled mineral water containing microplastics are presented. Exposure estimations based on the reported microplastic amounts found in mineral water and the assumption of total mass transfer of small molecules like additives and oligomers present in the plastic would not raise a safety concern. Available toxicokinetic data suggests that marginal fraction of the ingested low amount of microplastics can be absorbed, if at all, the conclusion is very likely that the reported amounts present in bottled mineral water do not raise a safety concern for the consumer. Considering the use of plastic materials in our daily life, occurrence of microplastics in beverages is likely a minor exposure pathway for plastic particles. Due to recent progress in analytical methods and the public discussion on plastics marine litter, public concern about eating and drinking microplastics with food, and related safety issues was raised. However, a better data basis for exposure estimates and risk assessment would be very helpful to better accommodate consumer concerns. The intention of this paper is to deliver a contribution to this topic taking the bottled mineral water as a case example.
1 April 2016 in Trends in Food Science & Technology
A model for estimating the migration of organic substances from plastic materials into foodstuffs has been previously developed. The use of this model allows a shift away from expensive and time consuming migration analysis in foods to much simpler and more economic compositional analysis in the material. Starting with toxicologically‐based specific migration values, like the over 400 specific migration limit values for organic substances listed in the European Union's Synoptic Document No. 7, the corresponding allowable maximum quantity limits of these substances in the plastic were calculated. The amount of migration that can occur depends on many different factors such as the natures of the plastic, substance and food, contact time and temperature conditions, material thickness and number of uses. These factors can result in a variety of situations which must be taken into account in the estimation of migration. The handling of the migration estimation model is demonstrated for several practical migration scenarios using a series of case studies.
21 December 2010 in Food Additives & Contaminants: Part A
Plastics bottles made from polyethylene terephthalate (PET) are increasingly used for soft drinks, mineral water, juices and beer. In this study a literature review is presented concerning antimony levels found both in PET materials as well as in foods and food simulants. On the other hand, 67 PET samples from the European bottle market were investigated for their residual antimony concentrations. A mean value of 224 ± 32 mg kg−1 was found, the median was 220 mg kg−1. Diffusion coefficients for antimony in PET bottle materials were experimentally determined at different temperature between 105 and 150°C. From these data, the activation energy of diffusion for antimony species from the PET bottle wall into beverages and food simulants was calculated. The obtained value of 189 kJ mol−1 was found to be in good agreement with published data on PET microwave trays (184 kJ mol−1). Based on these results, the migration of antimony into beverages was predicted by mathematical migration modelling for different surface/volume ratios and antimony bottle wall concentrations. The results were compared with literature data as well as international legal limits and guidelines values for drinking water and the migration limit set from food packaging legislation. It was concluded that antimony levels in beverages due to migration from PET bottles manufactured according to the state of the art can never reach or exceed the European-specific migration limit of 40 µg kg−1. Maximum migration levels caused by room-temperature storage even after 3 years will never be essentially higher than 2.5 µg kg−1 and in any case will be below the European limit of 5 µg kg−1 for drinking water. The results of this study confirm that the exposure of the consumer by antimony migration from PET bottles into beverages and even into edible oils reaches approximately 1% of the current tolerable daily intake (TDI) established by World Health Organisation (WHO). Having substantiated such low antimony levels in PET-bottled beverages, the often addressed question on oestrogenic effects caused by antimony from PET bottles appears to be groundless.