Plastic Food Contact Materials Research Articles

Genotoxicity testing approaches for the safety assessment of substances used in food contact materials prior to their authorization in the European Union.

Food contact materials are all materials and articles intended to come directly or indirectly into contact with food. Before being included in the positive European "Union list" of authorized substances (monomers, other starting substances and additives) for plastic food contact materials, the European Food Safety Authority (EFSA) must assess their safety "in use". If relevant for risk, the safety of the main impurities, reaction and degradation products originating from the manufacturing process is also evaluated. Information on genotoxicity is always required irrespective of the extent of migration and the resulting human exposure, in view of the theoretical lack of threshold for genotoxic events. The 2008 EFSA approach, requiring the testing of food contact materials in three in vitro mutagenicity tests, though still acceptable, is now superseded by the 2011 EFSA Scientific Committee's recommendation for only two complementary tests including a bacterial gene mutation test and an in vitro micronucleus test, to detect two main genetic endpoints (i.e., gene mutations and chromosome aberrations). Follow-up of in vitro positive results depends on the type of genetic effect and on the substance's systemic availability. In this study, we provide an analysis of the data on genotoxicity testing gathered by EFSA on food contact materials for the period 1992-2015. We also illustrate practical examples of the approaches that EFSA took when evaluating "non standard" food contact chemicals (e.g., polymeric additives, oligomer or other reaction mixtures, and nanosubstances). Additionally, EFSA's experience gained from using non testing methods and/or future possibilities in this area are discussed. Environ. Mol. Mutagen. 58:361-374, 2017. © 2017 Wiley Periodicals, Inc.

Administrative Guidance for the preparation of applications for the safety assessment of substances to be used in plastic Food Contact Materials

Administrative Guidance for the preparation of applications for the safety assessment of substances to be used in plastic Food Contact Materials

Porous Aromatic Framework 48/Gel Hybrid Material Coated Solid-Phase Microextraction Fiber for the Determination of the Migration of Styrene from Polystyrene Food Contact Materials.

A novel solid-phase microextraction (SPME) fiber was fabricated by a porous aromatic framework 48 (PAF-48)/gel hybrid material through a sol-gel process. PAF-48 is a porous organic framework (POF) material that was polymerized from 1,3,5-triphenylbenzene. The uniform pore structure, high surface area, continuous conjugate network, and hydrophobicity make PAF-48 expected to have special abilities to absorb and extract styrene as well as some other harmful volatile aromatic compounds (VACs). The PAF-48/gel-coated fiber was explored for the extraction of styrene and six VACs (benzene, toluene, ethylbenzene, and xylenes) from aqueous food simulants followed by gas chromatography (GC) separation. The fiber was found to be very sensitive for the determination of the target molecules with wide linear ranges (0.1-200 or 500 μg·kg-1), low limits of detection (LODs, 0.003-0.060 μg·kg-1), acceptable precisions (intraday relative standard deviation, RSD < 5.9%, interday RSD < 7.3%), and long lifetime (>200 times). Particularly for styrene, the PAF-48/gel-coated fiber exhibited a much lower LOD (0.006 μg·kg-1) compared with most of the reported fibers. Moreover, the PAF-48/gel-coated fiber had a high extraction selectivity for styrene and VACs over alcohols, phenols, aromatic amines, and alkanes and show a molecular sieving effect for the different molecule sizes. Finally, the PAF-48/gel-coated SPME fiber was successfully applied in GC for the determination of the specific migrations of styrene and VACs from polystyrene (PS) plastic food contact materials (FCMs).

Determination of primary aromatic amines in cold water extract of coloured paper napkin samples by liquid chromatography-tandem mass spectrometry

ABSTRACTThe aim of this study was the optimisation of a multi-analyte method for the analysis of primary aromatic amines (PAAs) from napkins in order to support official controls and food safety. We developed a UHPLC-MS/MS method for the simultaneous determination of 36 toxicologically relevant PAAs for paper and board. Good regression coefficients of the calibration curves in a range of 0.992–0.999 and reproducibilities in a range of 2.3–15% were obtained. Limits of detections (LODs) were in the range of 0.03–1.4 µg l–1 and recoveries were in a range of 21–110% for all the amines. A total of 93 coloured paper napkin samples from different European countries were bought and extracted with water to determine the PAAs. The results showed that 42 of 93 samples contained at least one PAA. More than half of the detected PAAs are considered as toxic, carcinogenic or probably carcinogenic to humans by the International Agency for Research on Cancer (IARC), or are classified as such in the European Union legislation on chemicals. Summed concentrations of PAAs in seven samples were higher than 10 µg l–1, the limit of summed PAA in the European Union plastic food contact material regulation. Also, eight PAAs, classified as Category 1A and 1B carcinogen in the European Union legislation of chemicals, were detected at concentrations higher than 2 µg l–1, exceeding the limit proposed by the Federal Institute for Risk Assessment in Germany. Aniline (n = 14) was most frequently present in higher concentrations followed by o-toluidine, o-anisidine, 2,4-dimethylaniline and 4-aminoazobenzene. Red, orange, yellow and multicoloured paper napkins contained the highest concentrations of total PAAs (> 10 µg l–1). Although the European Union has not harmonised the legislation of paper and board materials and, thus, there is no specific migration limit for PAAs from paper napkins, the present study showed that coloured paper napkins can contain toxic and carcinogenic PAAs at concentrations that are relevant for monitoring.

Attenuated total reflectance-mid infrared spectroscopy (ATR-MIR) coupled with independent components analysis (ICA): A fast method to determine plasticizers in polylactide (PLA)

Compliance of plastic food contact materials (FCMs) with regulatory specifications in force, requires a better knowledge of their interaction phenomena with food or food simulants in contact. However these migration tests could be very complex, expensive and time-consuming. Therefore, alternative procedures were introduced based on the determination of potential migrants in the initial material, allowing the use of mathematical modeling, worst case scenarios and other alternative approaches, for simple and fast compliance testing. In this work, polylactide (PLA), plasticized with four different plasticizers, was considered as a model plastic formulation. An innovative analytical approach was developed, based on the extraction of qualitative and quantitative information from attenuated total reflectance (ATR) mid-infrared (MIR) spectral fingerprints, using independent components analysis (ICA). Two novel chemometric methods, Random_ICA and ICA_corr_y, were used to determine the optimal number of independent components (ICs). Both qualitative and quantitative information, related to the identity and the quantity of plasticizers in PLA, were retrieved through a direct and fast analytical method, without any prior sample preparations. Through a single qualitative model with 11 ICs, a clear and clean classification of PLA samples was obtained, according to the identity of plasticizers incorporated in their formulations. Moreover, a quantitative model was established for each formulation, correlating proportions estimated by ICA and known concentrations of plasticizers in PLA. High coefficients of determination (higher than 0.96) and recoveries (higher than 95%) proved the good predictability of the proposed models.

Identification of substances migrating from plastic baby bottles using a combination of low-resolution and high-resolution mass spectrometric analysers coupled to gas and liquid chromatography.

This work presents a strategy for elucidation of unknown migrants from plastic food contact materials (baby bottles) using a combination of analytical techniques in an untargeted approach. First, gas chromatography (GC) coupled to mass spectrometry (MS) in electron ionisation mode was used to identify migrants through spectral library matching. When no acceptable match was obtained, a second analysis by GC-(electron ionisation) high resolution mass spectrometry time of flight (TOF) was applied to obtain accurate mass fragmentation spectra and isotopic patterns. Databases were then searched to find a possible elemental composition for the unknown compounds. Finally, a GC hybrid quadrupole-TOF-MS with an atmospheric pressure chemical ionisation source was used to obtain the molecular ion or the protonated molecule. Accurate mass data also provided additional information on the fragmentation behaviour as two acquisition functions with different collision energies were available (MS(E) approach). In the low-energy function, limited fragmentation took place, whereas for the high-energy function, fragmentation was enhanced. For less volatile unknowns, ultra-high pressure liquid chromatography-quadrupole-TOF-MS was additionally applied. Using a home-made database containing common migrating compounds and plastic additives, tentative identification was made for several positive findings based on accurate mass of the (de)protonated molecule, product ion fragments and characteristic isotopic ions. Six illustrative examples are shown to demonstrate the modus operandi and the difficulties encountered during identification. The combination of these techniques was proven to be a powerful tool for the elucidation of unknown migrating compounds from plastic baby bottles.

Food contact substances and chemicals of concern: a comparison of inventories

Food contact materials (FCMs) are intended to be in contact with food during production, handling or storage. They are one possible source of food contamination, because chemicals may migrate from the material into the food. More than 6000 FCM substances appear on regulatory or non-regulatory lists. Some of these substances have been linked to chronic diseases, whilst many others lack (sufficient) toxicological evaluation. The aim of this study was the identification of known FCM substances that are also considered to be chemicals of concern (COCs). The investigation was based on the following three FCM lists: (1) the 2013 Pew Charitable Trusts database of direct and indirect food additives legally used in the United States (or Pew for short), (2) the current European Union-wide positive list for plastic FCMs (or Union for short), and (3) the 2011 non-plastics FCM substances database published by EFSA (or ESCO for short). These three lists of food contact substances (Pew, Union, ESCO lists) were compared with the Substitute It Now! (SIN) list 2.1, which includes chemicals fulfilling the criteria listed in article 57 of Regulation (EC) No. 1907/2006 (REACH), and the TEDX database on endocrine-disrupting chemicals. A total of 175 chemicals used in FCMs were identified as COCs. Fifty-four substances present on the SIN list 2.1 were also found on the Union and/or ESCO lists. Twenty-one of those 54 substances are candidates for Substances of Very High Concern (SVHC), and six of these 21 are listed on Annex XIV and intended for phase-out under REACH. In conclusion, COCs used in FCMs were identified and information about their applications, regulatory status and potential hazards was included.

Scientific Opinion on the safety assessment of the active substances iron powder, activated carbon, calcined kaolin, sodium chloride, polyacrylic acid, sodium salt, crosslinked and calcium chloride, for use as active system in food contact materials

This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the active substances iron powder, activated carbon, calcined kaolin, sodium chloride, polyacrylic acid, sodium salt, crosslinked and calcium chloride, used in mixture which is packed into labels, for absorbing oxygen from the headspace surrounding packed food. All substances of this formulation have been evaluated and approved for use as additives in plastic food contact materials or as food supplements. Migration of substances from the labels and formation and release of volatile constituents are not expected under the intended conditions of use. The CEF Panel concluded that the use of substances iron powder, activated carbon, calcined kaolin, sodium chloride, polyacrylic acid, sodium salt, crosslinked and calcium chloride does not raise a safety concern when used in oxygen absorbers in labels, which prevent the physical release of their content into the food. When placed in the headspace of the packaging or when used in direct contact with foods, the labels should not intentionally or unintentionally come into direct contact with liquid foods or foods that have an external aqueous phase on the surface such as sliced fruits.

Scientific Opinion on the safety assessment of the active substances, sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulphate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water, for use as active system in food contact materials

This scientific opinion of EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the active substances sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulfate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water, used in mixture which is packed into sachets for absorbing oxygen/carbon dioxide emitting from/into the headspace surrounding packed food. All substances of this formulation have been evaluated and approved for use as additives in plastic food contact materials or as food additives. No migration of calcium, iron and sodium ions was detected. No volatile organic compounds other than carbon dioxide were detected at the limit of detection of 0.5 μg/l. The CEF Panel concluded that the use of the substances sodium erythorbate, sodium carbonate, sodium bicarbonate, iron sulfate, activated carbon, cellulose, calcium hydroxide, calcium chloride and water does not raise a safety concern when used in oxygen absorber/carbon dioxide emitter systems, in sachets that prevent the physical release of their contents into the food. The sachets are to be placed in the headspace of the packaging and as such may come into occasional contact with the food, e.g. during handling. The sachet should not come into direct contact with liquid foods or foods that have and external aqueous liquid phase on the surface (liquid or exudates).

Liquid chromatography–full scan-high resolution mass spectrometry-based method towards the comprehensive analysis of migration of primary aromatic amines from food packaging

European Union legislation has established that plastic food contact materials shall not release primary aromatic amines (PAAs), which are toxic compounds and suspected human carcinogens. As valid alternative to existing methods for PAA determination, which are based on spectrophotometric test or targeted liquid chromatography–tandem mass spectrometry (LC–MS/MS) approaches, in this study a LC-Orbitrap–full scan-high resolution mass spectrometry (HRMS) method was devised and validated for the determination of migration levels of 22 PAAs from food contact materials, thus exploiting the specificity of accurate mass measurement. Direct injection of the simulant (acetic acid 3%, w/v) into the LC–MS system after migration, without any pre-treatment step, makes the developed method of great value for rapid screening analysis of a large number of amines. A very fast and efficient separation (<11min) of PAAs was achieved. Detection limits in the 0.06–0.7μgkg−1 range were calculated for 17 out of 22 of the investigated PAAs, however obtaining values within 5.3μgkg−1 for the other 5 amines. Good dynamic linear ranges from two to four orders of magnitude (r2≥0.990) were obtained and satisfying results were achieved in terms of intra-day (RSDs<10%) and inter-day repeatability (RSDs<17%). Trueness values in the 70±1–131±5% range proved reliability of the developed method for PAAs quantification also at very low concentration levels. Finally, the method was successfully applied to a range of different real plastic multilayer food packaging materials, noticing in all cases levels below the established limits of detection.

A highly sensitive enzyme-linked immunosorbent assay for the detection of dipropyl phthalate in plastic food contact materials

A highly sensitive and specific direct competitive enzyme-linked immunosorbent assay has been developed for the detection of dipropyl phthalate (DPrP) based on antibody-coating format. The specific polyclonal antibodies against DPrP raised in rabbits. The conjugates of the antigen with horseradish peroxidase (HRP) were used as the detectable probe. Under the optimal conditions, the limit of detection of the method was 0.01 ng/mL, and a good quantitative working range of 0.01–16 ng/mL (R 2=0.995) was obtained. The cross-reactivities of four structurally related phthalate esters were below 12% and did not interfere significantly the analysis of DPrP. The accuracy of the immunoassay has been evaluated and validated by analyzing real and spiked leachate from plastic food contact materials. The recoveries of DPrP ranged from 85.9% to 109.4%. This developed dc-ELISA was reliable, accurate and highly sensitive.

Scientific Opinion on the safety evaluation of the active substances, iron, polyethyleneglycol, disodium pyrophosphate, monosodium phosphate and sodium chloride for use in food contact materials

This scientific opinion of EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of an iron based oxygen absorber, comprising polyethyleneglycol, disodium pyrophosphate, monosodium phosphate and sodium chloride. This mixture is incorporated in polyethylene (PE) or polypropylene (PP) articles intended to be in contact with foodstuffs for hot fill/pasteurisation and/or long term storage at room temperature. For dried and fatty foods, direct contact with the materials is envisaged whereas other food types will be separated from the active material by a layer that does not contain the active components. All the substances constituting the oxygen absorber system have been evaluated and authorised for use as plastic food contact materials, as food additives or as food supplements. Based on migration results, the specific migration limits for iron, polyethyleneglycol, pyrophosphoric acid salts, phosphoric acid salts and sodium chloride, and the tolerable intake of phosphorus (phosphate) are not expected to be exceeded when the oxygen absorber system is used under the intended conditions of use, notably behind a layer not containing the active substance for contact with aqueous or acidic foods. Therefore, the CEF Panel concluded that the use of the substances, iron, polyethyleneglycol, disodium pyrophosphate, monosodium phosphate and sodium chloride do not raise a safety concern when used as oxygen absorbers incorporated in polyethylene and in polypropylene articles used for long time storage and/or hot fill up to 95 °C for several minutes in i) direct contact with dry and fatty foods and ii) indirect contact with aqueous or acidic foods, separated from the active material by a layer of at least 10 µm polyethylene or polypropylene that does not contain the oxygen absorber formulation.

Uterotrophic and Hershberger Assays for Endocrine Disruption Properties of Plastic Food Contact Materials Polypropylene (PP) and Polyethylene Terephthalate (PET)

Plasticizers or plastic materials such as phthalates, bisphenol-A (BPA), and styrene are widely used in the plastic industry and are suspected endocrine-disrupting chemicals (EDC). Although plastic materials such as polypropylene (PP) and polyethylene terephthalate (PET) are not EDC and are considered to be safe, their potential properties as EDC have not been fully investigated. In this study, plastic samples eluted from plastic food containers (PP or PET) were investigated in Sprague-Dawley rats using Hershberger and uterotrophic assays. In the Hershberger assay, 6-wk-old castrated male rats were orally treated for 10 consecutive days with plastic effluent at 3 different doses (5 ml/kg) or vehicle control (corn oil, 1 ml/100 g) to determine the presence of both anti-androgenic and androgenic effects. Testosterone (0.4 mg/ml/kg) was subcutaneously administered for androgenic evaluation as a positive control, whereas testosterone (0.4 mg/ml/kg) and flutamide (3 mg/kg/day) were administered to a positive control group for anti-androgenic evaluation. The presence of any anti-androgenic or androgenic activities of plastic effluent was not detected. Sex accessory tissues such as ventral prostate or seminal vesicle showed no significant differences in weight between treated and control groups. For the uterotrophic assay, immature female rats were treated with plastic effluent at three different doses (5 ml/kg), with vehicle control (corn oil, 1 ml/100 g), or with ethinyl estradiol (3 μg/kg/d) for 3 d. There were no significant differences between test and control groups in vagina or uterine weight. Data suggest that effluents from plastic food containers do not appear to produce significant adverse effects according to Hershberger and uterotrophic assays.

Analysis of 16 phthalic acid esters in food simulants from plastic food contact materials by LC‐ESI‐MS/MS

An RP LC-ESI-MS/MS method for the determination of the migration of 16 primary phthalic acid esters from plastic samples has been developed using distilled water, 3% acetic acid, 10% alcohol, and olive oil as food simulants. Detection limits were 1.6-18.5 μg/kg in distilled water, 1.4-17.3 μg/kg in 3% acetic acid, 1.4-19.2 μg/kg in 10% alcohol, and 31.9-390.8 μg/kg in olive oil. The RSDs were in the range of 0.07-11.28%. The real plastic products inspection showed that only few analyzed samples were phthalates contaminated. Bis-2-ethylhexyl ester and dibutyl phthalate were the common items migrated from the plastic products into food and feeds, but the migration concentrations were far below the limits set by European Union (1.5 mg/kg for bis-2-ethylhexyl ester and 0.3 mg/kg for dibutyl phthalate).

Determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography with fluorescence detector

A method for the determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography (HPLC) with fluorescence detector was developed. The samples were extracted with trichloromethane by sonication for 30 min at 40 degrees C. The HPLC method was performed on a column of Eclipse XDB-C18 (250 mm x 4.6 mm, 5 microm) by gradient elution using 5 mmol/L ammonium acetate and acetonitrile as the mobile phases, and detected by the fluorescence detector at an excitation wavelength of 350 nm and an emission wavelength of 430 nm. The experimental results indicated that the four fluorescent whitening agents were separated well. The limits of detection (LOD) (S/N = 3) were 0.3, 0.1, 0.05, 0.14 mg/L, and the limits of quantification (LOQ) (S/N = 10) were 1.0, 0.4, 0.2, 0.5 mg/L for 1,4-bis (4-cyanostyryl) benzene (C. I. 199), 1,4-bis (2-benzoxazolyl) naphthalene (C. I. 367), 4,4'-bis(2-methoxystyryl) biphenyl (C. I. 378) and 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) (C. I. 184), respectively. Good linearities with correlation coefficients (r2) not less than 0.991 were obtained. The proposed method is simple, accurate, sensitive and can meet the requirements of the routine determination of fluorescent whitening agents in entry-exit products.

Scientific Opinion on the safety evaluation of the active substances, terephthalic acid, dimethyl ester, polymer with 1,4‐butanediol, cyclized, polymers with glycidyl methacrylate, hydroxyl‐terminated polybutadiene, methyl methacrylate and styrene, and cobalt stearate for use in food contact materials

This scientific opinion of EFSA deals with the safety evaluation of the oxygen absorber (terephthalic acid, dimethyl ester, polymer with 1,4-butanediol, cyclized, polymers with glycidyl methacrylate, hydroxyl-terminated polybutadiene, methyl methacrylate and styrene) copolymer (CAS No 1223402-34-3, FCM substance No 1005) and the oxidation catalyst cobalt stearate (CAS No 1002-88-6 and FCM Substance No 1004), intended to be used up to a maximum percentage of 1% in polyethylene terephtalate (PET) for absorbing oxygen from the food environment. All starting substances of the oxygen absorber formulation and cobalt stearate have been evaluated and approved for use as additives in plastic food contact materials. Methyl methacrylate, glycidyl methacrylate and cobalt stearate were not detected at the detection limits of 0.6, 0.006 and 0.0005 mg/kg food simulant, respectively. Butadiene was not detected in the PET bottles at a detection limit of 0.33 mg/kg plastic. For PET formulated with the maximum 1% of the active copoymer, the migration of the low molecular weight fraction (LMWF) of the copolymer was estimated to be less than 35 µg/kg food. The CEF Panel concluded that the use of the copolymer up to 1% w/w in PET for contact with all types of foods at temperature up to 95°C and the use of cobalt stearate as oxidation catalyst in PET, is not of safety concern for the consumer.

Scientific Opinion on the safety evaluation of the active substance iron (II) modified bentonite as oxygen absorber for use in active food contact materials

This scientific opinion of EFSA deals with the safety evaluation of the active substance iron (II) modified bentonite (FCM Substance No 1003) intended to be incorporated in monolayer or multilayer packages or in sachets for absorbing oxygen from the food environment. All starting substances of the oxygen absorber have been evaluated and approved for use as additives in plastic food contact materials or as food additives. From a toxicological point of view, migration of iron (incorporated) and aluminium (naturally present) ions from bentonite is of interest. Iron can be estimated to migrate up to 4.5 mg/kg acidic food, which is well below the SML value of 48 mg/kg food set in Regulation EU No 10/2011 based on the PMTDI of 0.8 mg/kg bw established by the Joint FAO/WHO Expert Committee on Food Additives in 1983) and the SCF in 1990. The iron (II) modified bentonite is intended and expected to be present in the final article as non-nanoform. However, the formation of nanoparticles due to exfoliation cannot be excluded if the substance is incorporated in unpolar polymers with compatibilisers or without such additives in polar polymers. Aluminium can be estimated to migrate up to 0.3 mg /kg acidic food. This value corresponds to 3.5 % of the TWI set in 2008 by the EFSA AFC Panel. Therefore, under the intended conditions of use, the oxygen absorber formulation was considered toxicologically acceptable. The CEF Panel concluded that the substance iron (II) modified bentonite does not raise a safety concern for the consumer when used as oxygen absorber incorporated without compatibilisers in polyolefin layers of food packages at levels up to 15% w/w. The substance equally does not raise a safety concern when it is used in sachets, placed in the headspace of the packaging, that prevent the physical release of their contents into the food and are not in direct contact with liquid foods, exudates, or foods with external aqueous liquid phase.

Scientific Opinion on the safety evaluation of the active substances, activated carbon, water, iron powder, kaolin calcined, sulphur and sodium chloride for use as active component in food contact materials

This scientific opinion of EFSA deals with the risk assessment of the active substances activated carbon (CAS No 7440-44-0, FCM Substance No 984), water (CAS No 7732-18-5, FCM Substance No 515), iron powder (CAS No 7439-89-6, FCM Substance No 983), kaolin calcined (CAS No 92704-41-1, FCM Substance No 753), sulphur (CAS No 7704-34-9, FCM Substance No 514), sodium chloride (CAS No 7647-14-5, FCM Substance No 985), used in mixtures which are packed into sachets for absorbing oxygen from the food environment. All substances of the oxygen absorber formulations have been evaluated and approved for use as additives in plastic food contact materials and/or as food supplements (sodium chloride). The CEF Panel concluded that the use of the substances activated carbon, water, iron powder, kaolin calcined, sulphur and sodium chloride, do not raise a safety concern when used in oxygen absorbers in sachets which would prevent the physical release of their contents into the food and placed in the headspace of the packaging or when used in direct contact with dry foods. The sachet should not intentionally or unintentionally come into direct contact with liquid foods or foods that have an external aqueous liquid phase on the surface such as sliced fruits and fresh meat. Activated carbon should in addition comply with the same purity requirements as for Vegetable Carbon (E 153) set out by Commission Directive 95/45/EC with exception of ash content which can be up to 10 % (w/w).

Threshold of toxicological concern approach for the risk assessment of substances used for the manufacture of plastic food contact materials

The objective of this work was to investigate whether the Threshold of Toxicological Concern (TTC) approach could be applied to the evaluation of substances used to manufacture plastic food contact materials (FCM). For this purpose, a new dataset of 232 substances used in FCM, fully evaluated on the basis of oral animal studies, was compared with the original Munro dataset. The extended dataset supports the differentiation between Cramer classes I and III, as the substances with the lowest no-observed-effect-levels are in class III both for the Munro et al. and the FCM datasets. The applicability of the TTC approach was also verified substance by substance, by comparing their TTC value with their tolerable intakes calculated from their no-observed-effect-level. The TTC approach, as proposed by Munro et al. in 1996, appears to be more conservative (more protective for consumers) than the complete individual risk assessment for 96% of the 845 compounds included in the investigation. For most of the substances, functional groups known to represent causes of non-applicability of the TTC approach have been identified. These figures suggest that the TTC approach can be a useful tool for prioritization of evaluations of lists of substances for which no toxicity data are available.

Effect of Migrant Size on Diffusion in Dry and Hydrated Polyamide 6

Food safety authorities have already allowed the use of mathematical models to predict diffusion from plastic food contact materials. These models use the molecular weight of the migrant as a cornerstone parameter that describes the contribution of the migrant to the diffusion process. In this work, the dependence of the diffusion coefficient on the migrant size was examined through fluorescence recovery after photobleaching (FRAP). A model migrant series of fluorescent probes was used, covering a wide molecular weight range. The advantage and originality of the tested migrant series are associated with the fact that the same shape and chemical functionality are maintained regardless of the molecular weight of the migrants. In this way the dependence of the acquired data on parameters other than size is excluded. The same experiments were carried out in dry and hydrated polyamide 6 to evaluate the effect of polymer matrix mobility in the "diffusion-migrant size" relationship. The experimental data were compared to well-known mathematical or semiempirical approaches, verifying that there is a relationship between the diffusion coefficient and the size of the migrant. However, it is demonstrated that this relationship is also affected by the mobility of the polymer matrix, becoming more pronounced as the mobility of the matrix decreases.