Suchergebnisse

Progressive expansion of nanomaterials in our everyday life raises concerns about their safety for human health. Although kidneys are the primary organs of xenobiotic elimination, little attention has been paid to the kidneys in terms of nanotoxicological studies up to now. Here we investigate the cytotoxic and genotoxic potential of four solid-core uncoated inorganic nanoparticles (TiO2NPs, SiO2NPs, Fe3O4NPs and AuNPs) using the human renal proximal tubule epithelial TH1 cells. To mimic the in vivo conditions more realistic, TH1 cells were exposed in vitro to inorganic NPs under static as well as dynamic conditions for 3 h and 24 h. The medium throughput alkaline comet assay (12 minigels per slide) was employed to evaluate the impact of these NPs on genome integrity and their capacity to produce oxidative lesions to DNA. The accumulation and localization of studied inorganic NPs inside the cells was monitored by transmission electron microscopy (TEM) and the efficacy of internalization of particular NPs was determined by atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). From all the tested NPs, only Fe3O4NPs induced a slight cytotoxicity in TH1 cells exposed to high concentrations (>700 μg/ml) for 24 h. On the other hand, the inorganic NPs did not increase significantly the level of DNA strand breaks or oxidative DNA damage regardless of the treatment mode (static vs. dynamic conditions). Interestingly, substantial differences were observed in the internalized amount of inorganic NPs in TH1 cells exposed to equivalent (2.2 μg/ml) concentration. Fe3O4NPs were most efficiently taken up while the lowest quantity of particles was determined in TiO2NPs-treated cells. As the particle size and shape of individual inorganic NPs in culture medium was nearly identical, it is reasonable to suppose that the chemical composition may contribute to the differences in the efficacy of NPs uptake. ; This article was created by the realization of the H2020 project HISENTS No. 685817, COST Action CA15132, VEGA grant 2/0056/17, project "Center of excellence of environmental health", ITMS No. 26240120033, based on the support of operational Research and development program financed from the European Regional Development Fund; and the EEA projectSK0020. Filip Razga received support within the SASPRO Programme (Project No. 0057/01/02) co-funded by the European Union and the Slovak Academy of Sciences. ; Peer reviewed

Despite the obvious advantages of gold nanoparticles for biomedical applications, controversial and incomplete toxicological data hamper their widespread use. Here, we present the results from an in vivo toxicity study using gold nanoparticles coated with polyethylene glycol (PEG-AuNPs). The pharmacokinetics and biodistribution of PEG-AuNPs were examined in the rat's liver, lung, spleen, and kidney after a single i.v. injection (0.7 mg/kg) at different time intervals. PEG-AuNPs had a relatively long blood circulation time and accumulated primarily in the liver and spleen, where they remained for up to 28 days after administration. Increased cytoplasmic vacuolation in hepatocytes 24 h and 7 days after PEG-AuNPs exposure and apoptotic-like cells in white splenic pulp 24 h after administration has been detected, however, 28 days post-exposure were no longer observed. In contrast, at this time point, we identified significant changes in lipid metabolism, altered levels of liver injury markers, and elevated monocyte count, but without marked biological relevance. In blood cells, no DNA damage was present in any of the studied time intervals, with the exception of DNA breakage transiently detected in primary kidney cells 4 h post-injection. Our results indicate that the tissue accumulation of PEG-AuNPs might result in late toxic effects. ; This paper is supported by European Union's Horizon 2020 research and innovation program under grant agreement No. 857381, project VISION (Strategies to strengthen scientific excellence and innovation capacity for early diagnosis of gastrointestinal cancers), project HISENTS No. 685817, VEGA grants 2/0055/20, 2/0121/21.

Abstract
The food enzyme α‐amylase (4‐α‐d‐glucan glucanohydrolase i.e. EC 3.2.1.1) is produced with the non‐genetically modified Cellulosimicrobium funkei strain AE‐AMT by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that the food enzyme did not give rise to safety concerns when used in seven food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of ten food manufacturing processes. As the food enzyme‐total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme‐TOS was estimated only for the remaining nine processes. The dietary exposure was calculated to be up to 0.049 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (230 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 4694. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Abstract
The food enzyme glucan 1,4‐α‐maltohydrolase (4‐α‐d‐glucan α‐maltohydrolase; EC 3.2.1.133) is produced with the genetically modified Saccharomyces cerevisiae strain LALL‐MA+ by Danstar Ferment AG. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for production of baked products. Dietary exposure was estimated to be up to 0.014 mg TOS/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and four matches were found, three with respiratory allergens and one with an allergen from mosquito (injected). The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Abstract
The food enzyme β‐galactosidase (β‐d‐galactoside galactohydrolase; EC 3.2.1.23) is produced with the genetically modified Bacillus licheniformis strain DSM 34099 by Kerry Group Services International, Ltd. (KGSI). The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. The production strain met the requirements for the qualified presumption of safety (QPS) approach. The food enzyme is intended to be used in two food manufacturing processes. Dietary exposure was estimated to be up to 7.263 mg total organic solids/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests, other than an assessment of allergenicity, were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and one match with a food allergen from kiwi fruit was found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to kiwi fruit, cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.