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1.
EFSA J ; 21(7): e08100, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37476081

RESUMO

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of poly(2-hydroxypropanoic acid), n-octyl/n-decyl esters (OLA8), which is intended to be used as a plasticiser into polylactic acid (PLA) in contact with non-fatty foods. OLA8 is intended to be used at up to 5% and 15% w/w with or without starch, respectively (or with other additives with similar function). The migration for 10 days at 40°C from the film without starch was 0.16 mg/kg in 10% ethanol and 0.01 mg/kg in 3% acetic acid, while from the film with the starch it was well above 0.05 mg/kg food in all simulants. Some of the testing conditions were inconsistently reported. The substance did not induce gene mutations in bacterial cells and did not induce structural chromosomal aberrations or polyploidy in mammalian cells, thus, does not raise concern for genotoxicity. Instead of providing a 90-day oral toxicity study, a hydrolysis study in ■■■■■ was submitted to read-across from the authorised starting substances, ■■■■■ and the ■■■■■. However, the data provided did not allow to perform the read-across, thus no appropriate toxicological data were provided to support migration above 0.05 mg/kg food (including for contact with 10% ethanol and use in combination with starch). The Panel concluded that OLA8 does not raise a safety concern for the consumer if it is used as an additive at up to 15% w/w in the manufacture of PLA articles that do not contain starch (and other additives with similar function), that are intended to be in contact for 10 days at 40°C with foods simulated by 3% acetic acid and from which the migration does not exceed 0.05 mg/kg food.

2.
EFSA J ; 21(2): e07761, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36743686

RESUMO

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP Panel) assessed the safety of the 'waxes, paraffinic, refined, derived from petroleum-based or synthetic hydrocarbon feedstock, low viscosity' (FCM No. 93), for which the uses were requested to be extended for articles in contact with fatty foods. Migration from low-density polyethylene samples containing 1% w/w of a representative wax was tested in food simulants. In fatty food simulants, the migration of mineral oil saturated hydrocarbons (MOSH) ≤ C35 was 142 mg/kg food, exceeding the overall migration limit for plastic FCM. Mineral oil aromatic hydrocarbons (MOAH) with at least two rings are largely removed during the manufacturing process. Based on various lines of evidence, the Panel concluded that any concern for the potential presence of MOAH with two or more conjugated aromatic rings can be ruled out. Based on the genotoxicity studies and on the content of polycyclic aromatic hydrocarbons (PAHs), the substance does not raise a concern for genotoxicity. Available toxicokinetic data showed a limited accumulation of MOSH. No adverse effects were observed up to the highest tested dose of 9 g/kg body weight per day in a 90-day repeated oral toxicity study in Sprague-Dawley rats. The available results showed that FCM No. 93 is devoid of endocrine activity. The provided information on chronic toxicity and carcinogenicity was limited and inadequate to reach conclusions on these endpoints. Therefore, the CEP Panel concluded that under the intended and tested conditions of uses, the substance does not raise safety concern for the consumer if used to a level ensuring that its migration into food is no more than 5 mg/kg.

3.
EFSA J ; 20(3): e07171, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35281648

RESUMO

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids assessed the safety of the substance bleached cellulose pulp, consisting of cellulose fibres (70-92%) and hemicellulose (8-30%) obtained from pine and spruce wood. The substance is intended to be used ■■■■■ in polyethylene and polypropylene food contact materials. The final articles are intended to be used for all food types and for long-term storage at room temperature, with or without a short time at higher temperature, including hot-fill. Low-density polyethylene samples containing ■■■■■ of the substance were subjected to a broad set of migration tests with food simulants and extraction tests with dichloromethane. The limits of detection ranged from ■■■■■ (when specified). The Panel noted that they do not ensure the detection of genotoxic substances at a concentration leading to a human exposure above the Threshold of Toxicological Concern. Moreover, not all possibly migrating substances were identified or amenable to the analytical methods applied. No toxicological data were provided for the substance itself, as its migration into food is not expected. The safety of the potentially migrating substances of low molecular mass detected was addressed individually and was considered adequate. However, the Panel considered this approach insufficient owing to a substantial fraction of unidentified components. The Panel concluded that the information provided by the applicant does not allow the safety assessment of the substances below 1,000 Da from bleached cellulose pulp from pine and spruce wood used in plastic food contact materials potentially migrating into food. Therefore, the Panel could not conclude on the safety of the use of bleached cellulose pulp from pine and spruce wood as a plastic additive.

4.
EFSA J ; 18(10): e06247, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33133270

RESUMO

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) was requested by the European Commission to re-evaluate the safety of styrene (FCM No 193) for use in plastic food contact materials (FCM) following the classification by the International Agency for Research on Cancer (IARC) as 'probably carcinogenic to humans'. The IARC Monograph pertains to hazard identification, based on studies on high-dose occupational exposures by inhalation and animal studies, also mainly by inhalation. The Panel considered that the IARC conclusions cannot be directly applied to the evaluation of risks for consumers from the oral exposure to styrene, but also concluded that, based on the data provided in the IARC Monograph and by the industry, a concern for genotoxicity associated with oral exposure to styrene cannot be excluded. The migration of styrene into foods packed in styrenic plastics is below 10 µg/kg for the majority of the foods, but up to 230 µg/kg was reported. Migration tends to be high for contact with fatty foods, and/or with high surface to volume ratios of the FCM. Dietary exposure of the consumers to styrene migrating from styrenic plastics was estimated in the order of 0.1 µg/kg body weight (bw) per day. It is in the same range as exposure from styrene present in foods as such. The dietary exposure (food component plus migration from styrenic plastics) is similar or lower than that by inhalation in the general population. Taking the human exposure data into account, the Panel concluded that a systematic review of genotoxicity and mechanistic data, comparative toxicokinetics and analysis of species differences is required for assessing the safety of styrene for its use in FCM.

5.
EFSA J ; 18(6): e06124, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32874315

RESUMO

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) was requested by the European Commission to review the substances for which a Specific Migration Limit (SML) is not assigned in Regulation (EU) No 10/2011. These substances had been covered by the Generic SML of 60 mg/kg food, but with Regulation (EU) 2016/1416 it was removed, necessitating their re-examination. EFSA was requested to identify those substances requiring an SML to ensure the authorisation is sufficiently protective to health, grouping them in high, medium and low priority to serve as the basis for future re-evaluations of individual substances. The CEP Panel established a stepwise procedure. This took into account existing hazard assessments for each substance on carcinogenicity/mutagenicity/reprotoxicity (CMR), bioaccumulation and endocrine disruptor (ED) properties along with the use of in silico generated predictions on genotoxicity. Molecular weights and boiling points were considered with regard to their effect on potential consumer exposure. This prioritisation procedure was applied to a total of 451 substances, from which 78 substances were eliminated at the outset, as they had previously been evaluated by EFSA as food contact substances. For 89 substances, the Panel concluded that a migration limit should not be needed. These are in the lists 0 and 1 of the Scientific Committee for Food (SCF), defined as substances for which an Acceptable Daily Intake (ADI) does not need to be established, along with substances that are controlled by existing restrictions and/or generic limits. Of the remaining 284 substances, 179 were placed into the low priority group, 102 were placed into the medium priority group and 3 were placed into the high priority group, i.e. salicylic acid (FCM No 121), styrene (FCM No 193) and lauric acid, vinyl ester (FCM No 436).

6.
Crit Rev Toxicol ; 49(9): 742-789, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31939687

RESUMO

For a few years, mineral oils and their potential adverse health effects have been a constant issue of concern in many regulatory areas such as food, cosmetics, other consumer products, and industrial chemicals. Analytically, two fractions can be distinguished: mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). This paper aims at assessing the bioaccumulative potential and associated histopathological effects of MOSH as well as the carcinogenic potential of MOAH for consumer-relevant mineral oils. It also covers the absorption, distribution, metabolism, and excretion of MOSH and MOAH upon oral and dermal exposures. The use and occurrence of consumer-relevant, highly refined mineral oils in food, cosmetics and medicinal products are summarized, and estimates for the exposure of consumers are provided. Also addressed are the challenges in characterizing the substance identity of mineral oil products under REACH. Evidence from more recent autopsy and biopsy studies, along with information on decreasing food contamination levels, indicates a low risk for adverse hepatic lesions that may arise from the retention of MOSH in the liver. With respect to MOAH, at present there is no indication of any carcinogenic effects in animals dermally or orally exposed to highly refined mineral oils and waxes. Such products are used not only in cosmetics but also in medicinal products and as additives in food contact materials. The safety of these mineral oil-containing products is thus indirectly documented by their prevalent and long-term use, with a simultaneous lack of clinical and epidemiological evidence for adverse health effects.


Assuntos
Cosméticos , Contaminação de Alimentos , Óleo Mineral , Animais , Exposição Ambiental/estatística & dados numéricos , Humanos , Hidrocarbonetos/análise , Hidrocarbonetos Aromáticos/análise
7.
PLoS One ; 7(6): e40000, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22768194

RESUMO

Protein kinase C iota is required for various cell biological processes including epithelial tissue polarity and organ morphogenesis. To gain mechanistic insight into different roles of this kinase, it is essential to identify specific substrate proteins in their cellular context. The analog-sensitive kinase method provides a powerful tool for the identification of kinase substrates under in vivo conditions. However, it has remained a major challenge to establish screens based on this method in multicellular model organisms. Here, we report the methodology for in vivo conditions using the analog-sensitive kinase method in a genetically-tractable vertebrate model organism, the zebrafish. With this approach, kinase substrates can uniquely be labeled in the developing zebrafish embryo using bulky ATPγS analogs which results in the thiophosphorylation of substrates. The labeling of kinase substrates with a thiophosphoester epitope differs from phosphoesters that are generated by all other kinases and allows for an enrichment of thiophosphopeptides by immunoaffinity purification. This study provides the foundation for using the analog-sensitive kinase method in the context of complex vertebrate development, physiology, or disease.


Assuntos
Ensaios Enzimáticos/métodos , Isoenzimas/metabolismo , Proteína Quinase C/metabolismo , Peixe-Zebra/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Embrião não Mamífero/enzimologia , Isoenzimas/química , Dados de Sequência Molecular , Proteínas Mutantes/química , Fosforilação , Proteína Quinase C/química , Especificidade por Substrato , Compostos de Sulfidrila/metabolismo , Peixe-Zebra/embriologia
8.
J Cell Sci ; 121(Pt 15): 2503-10, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18628301

RESUMO

The zebrafish MAGUK protein Nagie oko is a member of the evolutionarily conserved Crumbs protein complex and functions as a scaffolding protein involved in the stabilization of multi-protein assemblies at the tight junction. During zebrafish embryogenesis, mutations in nagie oko cause defects in both epithelial polarity and cardiac morphogenesis. We used deletion constructs of Nagie oko in functional rescue experiments to define domains essential for cell polarity, maintenance of epithelial integrity and cardiac morphogenesis. Inability of Nagie oko to interact with Crumbs proteins upon deletion of the PDZ domain recreates all aspects of the nagie oko mutant phenotype. Consistent with this observation, apical localization of Nagie oko within the myocardium and neural tube is dependent on Oko meduzy/Crumbs2a. Disruption of direct interactions with Patj or Lin-7, two other members of the Crumbs protein complex, via the bipartite L27 domains produces only partial nagie oko mutant phenotypes and does not impair correct junctional localization of the truncated Nagie oko deletion protein within myocardial cells. Similarly, loss of the evolutionarily conserved region 1 domain, which mediates binding to Par6, causes only a subset of the nagie oko mutant epithelial phenotypes. Finally, deletion of the C-terminus, including the entire guanylate kinase and the SH3 domains, renders the truncated Nagie oko protein inactive and recreates all features of the nagie oko mutant phenotype when tested in functional complementation assays. Our observations reveal a previously unknown diversity of alternative multi-protein assembly compositions of the Crumbs-Nagie-oko and Par6-aPKC protein complexes that are highly dependent on the developmental context.


Assuntos
Polaridade Celular/fisiologia , Células Epiteliais/metabolismo , Guanilato Ciclase/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Sítios de Ligação , Células Epiteliais/citologia , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Modelos Biológicos , Complexos Multiproteicos/metabolismo , Tubo Neural/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/análise
9.
J Vasc Res ; 45(2): 153-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17962719

RESUMO

Endothelial cell survival is indispensable to maintain endothelial integrity and initiate new vessel formation. We investigated the role of SHP-2 in endothelial cell survival and angiogenesis in vitro as well as in vivo. SHP-2 function in cultured human umbilical vein and human dermal microvascular endothelial cells was inhibited by either silencing the protein expression with antisense-oligodesoxynucleotides or treatment with a pharmacological inhibitor (PtpI IV). SHP-2 inhibition impaired capillary-like structure formation (p < 0.01; n = 8) in vitro as well as new vessel growth ex vivo(p < 0.05; n = 10) and in vivo in the chicken chorioallantoic membrane (p < 0.01, n = 4). Additionally, SHP-2 knock-down abrogated fibroblast growth factor 2 (FGF-2)-dependent endothelial proliferation measured by MTT reduction (p < 0.01; n = 12). The inhibitory effect of SHP-2 knock-down on vessel growth was mediated by increased endothelial apoptosis (annexin V staining, p < 0.05, n = 9), which was associated with reduced FGF-2-induced phosphorylation of phosphatidylinositol 3-kinase (PI3-K), Akt and extracellular regulated kinase 1/2 (ERK1/2) and involved diminished ERK1/2 phosphorylation after PI3-K inhibition (n = 3). These results suggest that SHP-2 regulates endothelial cell survival through PI3-K-Akt and mitogen-activated protein kinase pathways thereby strongly affecting new vessel formation. Thus, SHP-2 exhibits a pivotal role in angiogenesis and may represent an interesting target for therapeutic approaches controlling vessel growth.


Assuntos
Inibidores da Angiogênese/farmacologia , Membrana Corioalantoide/irrigação sanguínea , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Oligonucleotídeos Antissenso/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Células Endoteliais/enzimologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Técnicas de Cultura de Tecidos , Transfecção
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