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  • Migration of two antioxidants from packaging into a solid food and into Tenax
    Publication . Reinas, I.; Oliveira, J.; Pereira, J.; Machado, P.; Poças, M. F.
    The migration of chemicals from packaging materials into foods is an important issue in food safety and quality. European legislation sets specific migration limits which compliance must be assessed, surveyed and controlled by industry and authorities. Recently, the new Regulation UE 10/2011 included a new simulant - the Modified Polyphenylene Oxide (Tenax ) for solid dry foods. The objective of this work was to compare the migration kinetics of two antioxidants into Tenax as compared to rice at 3 temperatures: 23, 40 and 70 C. The application of two different solutions of the 2nd Fick’s law to describe and simulate the migration of the migrants to the present systems was studied. Diffusion coefficients ranged between 4.80E-13 and 2.84E-11 cm2/s for the migration into Tenax and between 6.90E-18 and 4.33E-17 cm2/s for the migration into rice. The partition coefficients ranged between 6 and 29 for Tenax and were over 1000 for rice. The activation energy for the migration into rice was half of that for Tenax . The models described relatively well the experimental data (ε < 12% and < 30% for rice and Tenax , respectively). Results indicate that the food simulant tends to overestimate migration values and thus can be safely used to assess materials compliance when materials are intended to contact with rice. However, results also indicate that Tenax is a much more severe simulant in representing rice.
  • Photoinitiators use in printed baby bibs and their migration into Tenax® by gas chromatography–mass spectrometry
    Publication . Galbiati, Edoardo; Pereira, Joel; Selbourne, Maria do Céu; Poças, Fátima
    A simple and accessible gas chromatography–mass spectrometry method was developed to determine photoinitiators (PIs) in plastics for food contact and their migration into Tenax®. The method showed analytical performance suitable for compliance assessment. The limit of detection values found were as follows: for benzophenone and 4‐(4‐morpholinyl)benzaldehyde ~3 μg kg−1 food (6 dm2 kg−1 food), for 4‐methylbenzophenone and ethyl‐4‐(dimethylamino)‐benzoate ~1.5 μg kg−1 food and for 2‐ethylhexyl 4‐(dimethylamino)benzoate ~43 μg kg−1 food. For all the other PIs studied, limits of detection lower than 1 μg kg−1 food were found. The method was applied to analyse samples of plastic baby bibs collected in European market. Results indicate that several unauthorised PIs are in use to print bibs. The most commonly detected PIs were benzophenone detected in nearly all samples and isopropylthioxanthone quantified in 12 out of 22 samples. Several non‐evaluated PIs were detected: triphenyl phosphate, 2‐ethylanthraquinone, 2,2‐dimethoxy‐2‐phenylacetophenone, 4‐(4‐methylphenyltio)benzophenone, 1‐hydroxycyclohexyl phenyl ketone and 4,4′‐bis(diethylamino)‐benzophenone. These two latter PIs were found at the highest concentration (more than 100 μgg−1). Testing a selection of samples for migration into Tenax® gave results exceeding the applicable migration limit for 1‐hydroxycyclohexyl phenyl ketone with 0.532 mg kg−1 (specific migration limit = 0.01 mg kg−1) and for methyl 2‐benzoylbenzoate with 0.182 mg kg−1 (specific migration limit = 0.05 mg kg−1). Although the results may be affected by a certain overestimation degree given the experimental conditions, they certainly flag an area of potential interest for surveillance and more detailed risk evaluation, particularly because bibs are often not seen by industry as food contact materials, and surveillance actions are not systematically acted.
  • Consumer exposure to phthalates from paper packaging: an integrated approach
    Publication . Poças, M.F.; Oliveira, J.C.; Pereira, J.R; Hogg, T.
    This paper presents an integrated approach to estimate the exposure of the Portuguese population to phthalates as a contaminant originating from paperboard packaging. The approach combined data of migrant concentration in the foods resulting from a stochastic simulation with consumption data of food packaged in paperboard. The results from the exposure model were validated with experimental values actually found in the food. A short surveillance exercise was conducted with samples collection from market shelves to identify and quantify the phthalates present in both the packages and the food. The distribution of values for the di-butyl phthalate concentration in the packages was used as the input of the initial concentration in the Weibull model to estimate the concentration of this phthalate in the foods. This distribution of occurrence data was then combined with the packaging usage data in a probabilistic simulation with a Monte Carlo sampling method. Exposure values ranged between zero and 8.95 mg day 1 kgbw, a value close to the tolerable daily intake established by the European Food Safety Authority (EFSA) – 10 mg day 1 kgbw. However, the 97.5th percentile and the average were 1.82 and 0.44 day 1 kgbw, respectively, indicating that further refinement of the estimates is not necessary. Other phthalates were also detected in the packaging samples: di-isobutyl phthalate and di-ethylhexyl phthalate. The latter was present in all packaging samples collected and was detected in a few food samples at values requiring further investigation.
  • Assessment of baby Bibs. GC-MS screening, migration into saliva and insight of toxicity with QSAR tools
    Publication . Rajbux, Chandisree; Pereira, Joel; Selbourne, Maria do Céu; Costa-Pinto, Ana Rita; Poças, Fátima
    Plastic baby Bibs are, according to the European legislation, food contact materials. Therefore, compositional and migration limits applicable to plastics should be observed. This work aimed at identifying potential migrants in Bibs from European market and determining the migration into artificial saliva. Bibs were subjected to screening analyses (GC-MS). Thirty substances non-authorised in European or Swiss legislation were detected: phthalates, light stabilizers, flame retardants and photoinitiators. Irgacure 184, Cyclohexanone, Tinuvin 770, Isophorone and 9-Octadecenamide, (Z)- were detected in saliva after contact with selected Bibs. The migration values render two samples noncompliant although results should be interpreted with caution given the experimental conditions. In order to gain insight on the toxicity of migrants, QSAR tools were applied. Substances non-evaluated or not-listed were analysed with free software regarding their Cramer class (ToxTree and their predicted mutagenicity, carcinogenicity and developmental toxicity (VEGA). Results indicate that surveillance is required: monitoring Bibs'compliance, application of GMPs and traceability.
  • Modelling migration from paper into a food simulant
    Publication . Poças, Maria de Fátima; Oliveira, Jorge C.; Pereira, Joel R.; Brandsch, Rainer; Hogg, Tim
    The migration of components from paper into Tenax (R) was studied to determine the influence of molecular size and chemical character of the migrant and the influence of paper characteristics in the migration process The Weibull model was applied because Fick s 2nd law of diffusion gave poor fits in some cases The migration pattern depended on the migrants molecular size and was independent of temperature in the studied range The migration rate decreased with the migrant molecular size The influence of the migrants character (polarity and vapour pressure) on the migration behaviour was also studied nonpolar migrants with high vapour pressure presented low relative migration values and polar migrants presented high values of relative migration Results indicated that the apparent partition coefficient between paper and the simulant Tenax (R) increased with the migrant vapour pressure and with both the paper grammage and the recycled pulp content
  • Characterization of patterns of food packaging usage in portuguese homes
    Publication . Poças, M. F. F.; Oliveira, J. C.; Pinto, H. J.; Zacarias, M. E.; Hogg, T.
    This study aimed to further refine the exposure assessment of migrants from food-contact materials by characterizing, at the household level, food packaging usage (amount and type) in Portuguese urban families. Packages from domestic use were collected from a sample of 105 consumers from 34 households over a 30-day period. Collected packages (more than 6000 items) were characterized in the laboratory and data were used to estimate: (i) global packaging usage and food intake; (ii) the consumption factors (CF) that describe the fraction of the daily diet expected to be in contact with specific packaging materials and (iii) the food-type factors (FTF) that reflect the fraction of all food contacting each material which differ in nature according to six major types: aqueous, acidic, alcoholic, milky, fatty and dry. The daily intake of packaged food and beverages consumed at home ranged from 5–50 g kg 1 bw. Considering all materials, total package usage ranged from 0.1 to 0.6dm2 day 1 kg 1 bw. The ratio between package surface area in contact and the quantity of food was determined for all packaging items collected and an average value of 25 dm2 kg 1 food was recorded. Data were gathered and presented in a manner compatible with current probabilistic approaches to exposure assessment. In this way, relevant consumption patterns from this type of population can be best represented in exposure assessments and subsequent risk assessments.
  • Feasibility study on the use of probabilistic migration modeling in support of exposure assessment from food contact materials
    Publication . Poças, Maria F.; Oliveira, Jorge C.; Brandsch, Rainer; Hogg, Tim
    The use of probabilistic approaches in exposure assessments of contaminants migrating from food packages is of increasing interest but the lack of concentration or migration data is often referred as a limitation. Data accounting for the variability and uncertainty that can be expected in migration, for example, due to heterogeneity in the packaging system, variation of the temperature along the distribution chain, and different time of consumption of each individual package, are required for probabilistic analysis. The objective of this work was to characterize quantitatively the uncertainty and variability in estimates of migration. AMonte Carlo simulation was applied to a typical solution of the Fick’s law with given variability in the input parameters. The analysis was performed based on experimental data of a model system (migration of Irgafos 168 from polyethylene into isooctane) and illustrates how important sources of variability and uncertainty can be identified in order to refine analyses. For long migration times and controlled conditions of temperature the affinity of the migrant to the food can be the major factor determining the variability in the migration values (more than 70% of variance). In situations where both the time of consumption and temperature can vary, these factors can be responsible, respectively, for more than 60% and 20% of the variance in the migration estimates. The approach presented can be used with databases from consumption surveys to yield a true probabilistic estimate of exposure.