Martine Kolf-Clauw

The food contaminant deoxynivalenol, decreases intestinal barrier permeability and reduces claudin expression

The gastrointestinal tract represents the first barrier against food contaminants as well as the first target for these toxicants. Deoxynivalenol (DON) is a mycotoxin that commonly contaminates cereals and causes various toxicological effects. Through consumption of contaminated cereals and cereal products, human and pigs are exposed to this mycotoxin. Using in vitro, ex vivo and in vivo approaches, we investigated the effects of DON on the intestinal epithelium. We demonstrated that, in intestinal epithelial cell lines from porcine (IPEC-1) or human (Caco-2) origin, DON decreases trans-epithelial electrical resistance (TEER) and increases in a time and dose-dependent manner the paracellular permeability to 4 kDa dextran and to pathogenic Escherichia coli across intestinal cell monolayers. In pig explants treated with DON, we also observed an increased permeability of intestinal tissue. These alterations of barrier function were associated with a specific reduction in the expression of claudins, which was also seen in vivo in the jejunum of piglets exposed to DON-contaminated feed. In conclusion, DON alters claudin expression and decreases the barrier function of the intestinal epithelium. Considering that high levels of DON may be present in food or feed, consumption of DON-contaminated food/feed may induce intestinal damage and has consequences for human and animal health.

Conclusions of the French Food Safety Agency on the toxicity of bisphenol A

Since more than 10 years, risk assessment of bisphenol A (BPA) is debated at the international level. In 2008, the U.S. National Toxicology Program (NTP) expressed some concern for adverse effects, at current level of exposure to BPA, on developmental toxicity. In this context, the French Food Safety Agency (AFSSA) decided to review the toxicity data on BPA with a special focus on this endpoint at doses below 5mg/kg bw/day (the no observed adverse effect level set by different regulatory bodies). This paper summarizes the conclusions of a collective assessment conducted by an expert Working Group from AFSSA. Studies were classified into 3 groups: (i) finding no toxicity, (ii) reporting results not considered to be of concern and (iii) indicating warning signals. The term warning signal means that no formal conclusion can be drawn regarding the establishment of a health based guidance value but the study raises some questions about the toxicity of BPA at low doses. It was concluded that studies are needed to ascertain the significance for human health of these warning signals and to be able to propose new methodologies for assessing the risks associated with low doses of BPA and more generally of endocrine disruptors.

Nivalenol has a greater impact than deoxynivalenol on pig jejunum mucosa in vitro on explants and in vivo on intestinal loops

The mycotoxins deoxynivalenol (DON) and nivalenol (NIV), worldwide cereal contaminants, raise concerns for animal and human gut health, following contaminated food or feed ingestion. The impact of DON and NIV on intestinal mucosa was investigated after acute exposure, in vitro and in vivo. The histological changes induced by DON and NIV were analyzed after four-hour exposure on pig jejunum explants and loops, two alternative models. On explants, dose-dependent increases in the histological changes were induced by DON and NIV, with a two-fold increase in lesion severity at 10 µM NIV. On loops, NIV had a greater impact on the mucosa than DON. The overall proliferative cells showed 30% and 13% decrease after NIV and DON exposure, respectively, and NIV increased the proliferative index of crypt enterocytes. NIV also increased apoptosis at the top of villi and reduced by almost half the proliferative/apoptotic cell ratio. Lamina propria cells (mainly immune cells) were more sensitive than enterocytes (epithelial cells) to apoptosis induced by NIV. Our results demonstrate a greater impact of NIV than DON on the intestinal mucosa, both in vitro and in vivo, and highlight the need of a specific hazard characterization for NIV risk assessment.

Safety assessment of the active substances carboxymethylcellulose, acetylated distarch phosphate, bentonite, boric acid and aluminium sulfate, for use in active food contact materials

Abstract This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety evaluation of the active substances carboxymethylcellulose, acetylated distarch phosphate (FCM substance No 1071), bentonite, boric acid and aluminium sulfate (FCM substance No 1072). The mixture is intended to be used as a liquid absorber in the packaging of perishable foods to extend their shelf‐life. All substances have been evaluated and approved for use as additives in plastic food contact materials and/or as food additives. Migration of boron into foods was up to 0.7 mg/kg food. Migration of aluminium was not detected (limit of detection (LOD) of 0.001 mg/kg). The CEF Panel concludes that the substances carboxymethylcellulose, acetylated distarch phosphate, bentonite, boric acid and aluminium sulfate are not of safety concern for the consumer when used as active components in moisture and liquid absorbers. The absorbent pads must be used under conditions in which direct contact between the active mixture and the food is avoided and the fluid absorption capacity of the absorber is not exceeded.

Safety assessment of the substance poly((R)‐3‐hydroxybutyrate‐co‐(R)‐3‐hydroxyhexanoate) for use in food contact materials

Abstract This opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety assessment of poly((R)‐3‐hydroxybutyrate‐co‐(R)‐3‐hydroxyhexanoate), Chemical Abstracts Service (CAS) No 147398‐31‐0 and food contact material (FCM) substance No 1059, for contact with dry/solid food. This biodegradable (co)polymer is produced by fermentation of palm oil using a genetically modified microorganism (Cupriavidus necator). No migration of oligomers into food simulant E (10 days at 40 and 60°C) was found at a detection limit per single oligomer of 5 μg/kg food. Migration of the degradation product crotonic acid was 8 and 25 μg/kg at the two test temperatures, respectively. The other migrating substances detected, ■■■■■, likely originated from or are related to the authorised substance (FCM No. 9) ‘palm oil and/or palm fatty acid distillate’ used as carbon source for the fermentation. At the migration levels reported, these migrants do not give rise to safety concern. No genotoxicity data are required for poly((R)‐3‐hydroxybutyrate‐co‐(R)‐3‐hydroxyhexanoate) because of its high molecular weight. The fraction below 1,000 Da is 0.5%. The major monomeric unit in the copolymer, 3‐hydroxybutyric acid, is an intermediate in fatty acid metabolism. The minor monomeric unit, 3‐hydroxyhexanoic acid, tested negative for bacterial gene mutations. Degradation products, which may be present in the (co)polymer, are crotonic acid and (E)‐2‐hexenoic acid. Crotonic acid is authorised for use in FCM with a specific migration limit (SML) of 0.05 mg/kg food; for (E)‐2‐hexenoic acid, no indication for genotoxicity was identified by the EFSA CEF Panel in its 2010 group evaluation of flavouring substances in FGE.05Rev2. The CEF Panel concluded that the substance poly((R)‐3‐hydroxybutyrate‐co‐(R)‐3‐hydroxyhexanoate) is not of safety concern if used alone or in blends with other polymers for contact with dry/solid food. If the SML of crotonic acid is met, migration of (E)‐2‐hexenoic acid will also not exceed 0.05 mg/kg food.

Safety assessment of the substance 1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylic acid, dimethyl ester for use in food contact materials

Abstract This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing aids (CEF Panel) deals with the safety assessment of 1,2,3,4‐tetrahydronaphthalene‐2,6‐dicarboxylic acid, dimethyl ester (TDCM) for use as a co‐monomer to manufacture polyester layers. The polyester layer is not intended to be in direct contact with food. The finished multilayer articles are intended for packaging aqueous, acidic and low alcoholic foodstuffs. Contact conditions include sterilisation followed by long‐term storage at room temperature. No thermal degradation of TDCM is expected during the manufacture of the middle polyester layer and of the multilayer articles. Total mass transfer of the substance from a polyester monolayer was calculated to be up to 0.032 mg/kg food. Based on three in vitro genotoxicity tests, the CEF Panel considered that the substance does not raise concern for genotoxicity. When tested behind a polypropylene layer, migrating TDCM‐related oligomers, their oxidation products and other related reaction products were identified. The major components were TDCM dimers. When tested behind a cyclo‐olefin polymer layer, none of the TDCM‐related substances were found to migrate. Based on the lack of genotoxicity of the co‐monomer, the ester nature of the oligomers and on (quantitative) structure–activity relationship ((Q)SAR) analysis, the CEF Panel considered that there is no indication of genotoxicity for the oligomers, their oxidation products and other TDCM‐related reaction products. The CEF Panel concluded that the substance is not of safety concern for the consumer if used as a co‐monomer for the manufacture of a polyester layer intended to be used as an inner (non‐food contact) layer of a multilayer material for contact with foods simulated by simulants A, B, C, D1 (as set in Regulation (EU) 10/2011). The migration of the sum of the substance and the dimers (cyclic and open chain) should not exceed 0.05 mg/kg food.

Safety assessment of the substance [3‐(2,3‐epoxypropoxy)propyl]trimethoxy silane, for use in food contact materials

Abstract This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety evaluation of [3‐(2,3‐epoxypropoxy)propyl]trimethoxy silane as a component for sizing glass fibres used for manufacturing glass‐fibre‐reinforced plastics. The substance is typically applied at up to around 0.2% related to the final plastic. The resulting food contact materials are intended for various scenarios of use, i.e. long‐term contact at ambient temperature (e.g. storage tanks) or short‐term contact at elevated temperatures (e.g. kitchen utensils). In extracts of treated fibres, neither the substance was detectable at 10 μg/kg fibre nor its hydrolysis product and oligomers at 60 μg/kg fibre. Based on the detection limits, modelling for the plastics and scenarios of intended use resulted in maximum migrations of 0.05 μg/kg food for the substance and 0.15 μg/kg food for the sum of the reaction products. The Panel concludes that the substance has a genotoxic potential. This may also apply to some of its reaction products which contain the epoxy function. However, due to the very low exposure, if any, [3‐(2,3‐epoxypropoxy)propyl]trimethoxy silane does not raise safety concern if used as a component of sizing agents to treat glass fibres imbedded into low diffusivity plastics (polyethylene terephthalate, polycarbonate, polybutylene terephthalate, thermoset polyesters and epoxy bisphenol vinylester) in contact with all foodstuffs. In addition, the residues in the treated glass fibres must not be detectable at 10 μg/kg for the substance and 60 μg/kg for each of the reaction products (hydrolysed monomers and epoxy‐containing cyclic dimer, trimer and tetramer).

Safety assessment of the substance phosphorous acid, mixed 2,4‐bis(1,1‐dimethylpropyl)phenyl and 4‐(1,1‐dimethylpropyl)phenyl triesters for use in food contact materials

Abstract This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety assessment of the substance phosphorous acid, mixed 2,4‐bis(1,1‐dimethylpropyl)phenyl and 4‐(1,1‐dimethylpropyl)phenyl triesters. The substance was evaluated by the CEF Panel in 2011 and 2,4‐di‐tert‐amylphenol, an impurity and hydrolysis product was re‐evaluated by the CEF Panel in 2015. In this application, the applicant requested an increase of the specific migration limit of the substance, currently established at 5 mg/kg food, to 10 mg/kg food, and provided new toxicological studies. Findings from three new in vitro mutagenicity assays on the oxidation products support the conclusion from 2011 that the substance and its oxidation products are not genotoxic. A new toxicokinetic study on the substance supports the consideration from the evaluation in 2011 that the substance does not raise concern for accumulation. The outcome of a new delayed neurotoxicity study on a structurally related substance, phosphorous acid, tris (2,4‐di‐tert‐butylphenyl) ester, which was considered not to cause neurotoxicity in hens, strengthens the conclusion of the Panel in 2011 that the substance does not represent a concern for neurotoxicity. From a new two‐generation reproduction toxicity study and a prenatal developmental toxicity study on the substance, a new subchronic toxicity study on its oxidation products that completes the one submitted in 2011 on the substance itself, and a 2‐year oral toxicity study on the structurally related substance, the lowest NOAEL was 58–147 mg/kg bw per day (from the 2‐year oral toxicity study). Compared to the requested increase of the migration limit, this gives an acceptable margin of safety of 348. Therefore, the CEF Panel concluded that an increase of the specific migration limit of the substance from 5 to 10 mg/kg food is not a safety concern for the consumer.

Safety assessment of the mixture of methyl-branched and linear C14–C18 alkanamides, derived from fatty acids, for use in food contact materials

Abstract This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety assessment of the mixture of methyl‐branched and linear C14–C18 alkanamides, derived from fatty acids, for use in food contact materials as a slip or release agent at up to 1% w/w in polyolefins. The final materials are intended for contact with foodstuffs other than fatty foods for long‐term storage at room temperature including short heating. No thermal degradation of the substance is expected under manufacturing process conditions of polyolefins. Specific migration from low‐density polyethylene (LDPE) made with 0.37% of the substance into 3% acetic acid and 10% ethanol was up to 0.68 mg/kg. Based on negative results in a bacterial mutation test and in an in vivo micronucleus test, there was no evidence of a genotoxic potential of the substance. Impurities were determined and the main ones were tested in a bacterial mutation test giving negative results. Along with the negative results from the in vivo micronucleus test on the substance containing the impurities, there was no evidence of a genotoxic potential of the impurities. Based on a 28‐day study on the substance, the Panel noted that there is sufficient margin of safety between the no observed adverse effect level (NOAEL) and the maximum exposure of consumers that could occur at a migration level of 5 mg/kg food, to cover uncertainties about toxic effects due to potential accumulation of slowly hydrolysed branched amide species of the substance during chronic exposure. The CEF Panel concluded that the substance is not of safety concern for consumers if it is used in the manufacture of polyolefin articles intended for contact with all foodstuffs other than fatty foods and the migration does not exceed 5 mg/kg food. The 5 mg/kg food migration should not apply to n‐stearamide.

Safety assessment of the substance ‘Tungsten Oxide’ for use in food contact materials

Abstract This scientific opinion of EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the risk assessment of the additive tungsten oxide, CAS No 39318‐18‐8 and FCM No 1064, for use in food contact materials as a reheat agent in polyethylene terephthalate (PET) at a maximum use level of 75 ppm (75 mg/kg PET). The substance is a mixture of tungsten oxides with tungsten at different oxidative levels. The average oxidation level of tungsten in the oxides is 2.86 corresponding to 19.93% oxygen content. Detailed information on impurities is provided as confidential. Specific migration from PET plaques with the substance at 150 mg/kg (double the maximum intended use level of 75 mg/kg) was determined into 95% ethanol, as a worst‐case simulant for PET due to its swelling effect. Under these test conditions, the specific migration, measured as tungsten using ICP‐MS, was at the level of 1 μg/kg. The Panel considered that due to the insolubility of the substance, this low migration will be typical for any foreseeable use as a reheat additive in PET. Two in vitro genotoxicity studies, a bacterial gene mutation test and an in vitro micronucleus assay, performed in accordance with the OECD Guidelines and in compliance with GLP, were provided by the applicant for the substance tungsten oxide and were considered negative by the CEF Panel. According to a scientific opinion on strategy for genotoxicity testing (EFSA, 2011), the three genotoxic endpoints, gene mutation, chromosomal and numerical aberrations, are covered by these two tests. The CEF Panel concluded that the substance tungsten oxide is not of safety concern for the consumer if the additive is used as a reheat agent in PET. For other technical functions or for use in other polymers, the migration should not exceed 50 μg/kg (expressed as tungsten).