Search

The aim of this risk assessment study was to estimate the dietary acrylamide (AA) intake of the population in Cyprus, to carry out the necessary risk characterization and to calculate the contribution rate of the major food groups to the AA exposure. Exposure assessment was performed using the EU MENU Food Consumption data and the risk assessment model ImproRisk©. The mean and 95th percentile dietary intake values, based on mean AA concentrations, were 0.66 and 1.84 μg/kg b.w. per day, respectively. The estimated levels of dietary exposure to AA are not of concern with respect to neurotoxicity. However the margins of exposure (MOEs) indicate a concern for carcinogenicity. Fried potatoes (32.9%), rusks and crispbread (18%), potato chips (9.2%) and biscuits (8.8%) contributed the most to overall AA exposure. Finally, the uncertainties affecting the above exposure assessment were identified and assessed., CY; doc; efsafocalpoint@sgl.moh.gov.cy

The aim of this study was to estimate the dietary Aflatoxin B1 (AFB1) intake of the adolescent population in Cyprus at EFSA FoodEx1(1) Level 3 and Level 2, to compare these exposure estimates with the BMDL10 intake value of 0.17 μg/kg b.w. per day for carcinogenicity in animals and to calculate the contribution rate of the major food groups to the AFB1 exposure. AFB1 occurrence data in food (n=1231) for 2005-2013 were used. The consumption data were obtained from the Child Health Database for adolescents 11-15 years of age, which was created in 2003 in Cyprus. The ImproRisk model has been upgraded for refinement purposes: ImproRisk version 1.4 BETA calculates the exposure using occurrence data at FoodEx Level 2. The upgraded v. 1.4.1 BETA estimates the intake at Level 3. This study presents the refined estimation of the exposure of Aflatoxin B1 (AFB1) , at FoodEx Level 3. The mean and 95th percentile dietary intake values, based on mean AFB1 concentrations, were 0.001 & 0.002 μg/kg b.w. per day for FoodEx Level 2, and 0.0007 & 0.0013 μg/kg b.w. per day for FoodEx Level 3, respectively. These values are much lower than the BMDL10 value. At the same time, the MOE values are much less than 10000, even if we take into account the BMDL10 of 0.87 μg/kg b.w per day for carcinogenicity in humans, so the current levels of exposure are of public health concern. Nevertheless, MOE is just an indicative measure of risk and it does not substitute the ALARA (As Low As Reasonably Achievable) principle. The exposure at FoodEx Level 3 resulted in a more accurate picture in relation to the contribution of food groups to the total AFB1 intake. Specifically, the highest exposure was estimated for grains and grain-based products (50%), especially rice, followed by spices (chilli, pepper, etc.) (40%)., CY; en; efsafocalpoint@sgl.moh.gov.cy

Glycerol (G, a triol) and sebacic acid (S, an α,ω-dicarboxylic acid) were condensed in the bulk to obtain poly(glycerol sebacate) (PGS) cross-linked elastomers which were characterized in terms of their swelling, thermal, and mechanical properties. The soluble precursors to the elastomers were characterized in terms of their size, size distribution, and composition. In particular, G-S mixtures of five different compositions (molar G:S ratio = 2:1, 2:2, 2:3, 2:4, and 2:5) were copolymerized in the bulk at 120 C in a three-step strategy (first step under inert gas atmosphere, followed by two steps in vacuo). When the G:S molar ratio was equal to (2:3) or close to (2:4), the stoichiometrically matched, network formation took place from the second condensation step, whereas three reaction steps were necessary for network formation far from stoichiometry, at G:S molar ratios equal to 2:2 and 2:5 at a G:S molar ratio of 2:1, no network formation was observed at all. Network composition also proved to be an important structural property, directly influencing the swelling and thermomechanical behavior of the elastomers. In particular, at the stoichiometrically matched G:S ratio of 2:3, corresponding to the cross-linking density maximum, the sol fraction extracted from the elastomers and the elastomer degree of swelling in aqueous media and in organic solvents presented a minimum, whereas the storage moduli of PGS elastomeric membranes in the dry state, measured within the temperature range between 35 and 140 C, exhibited a maximum. The molecular weights of all soluble network precursors were found to be below 5000 g mol-1 (gel permeation chromatography), containing but traces of ring oligomers (electron-spray ionization mass spectrometry). 1H NMR spectroscopy indicated that the precursor composition was close to that expected on the basis of the G:S feed ratio and that monomer-to-polymer conversion increased from the first to the second condensation step. © 2013 American Chemical Society. 46 3 622 630 Cited By :14

The aim of this risk assessment study was to estimate the dietary acrylamide (AA) intake of the adolescent population in Cyprus, to carry out the necessary risk assessment and to calculate the contribution rate of the major food groups to the AA exposure. AA is considered to be neurotoxic in humans and is classified as a probable human carcinogen. Exposure assessment was performed using ImproRisk©. The mean and 95th percentile dietary intake values, based on mean AA concentrations, were 0.8 and 1.8 μg/kg b.w. per day, respectively. The estimated levels of dietary exposure to AA are not of concern with respect to neurotoxicity. However the margins of exposure (MOEs) indicate a concern for carcinogenicity. Potato fried products (45%), fine bakery ware (biscuits, rusks, crackers, pastries and cakes) (21%) and potato chips (14%) contributed the most to overall AA exposure. Finally, the uncertainties affecting the above exposure assessment were identified and assessed., CY; en; efsafocalpoint@sgl.moh.gov.cy

Semisegmented amphiphilic polymer conetworks (APCNs) based on the hydrophilic monomer 2-(dimethylamino)ethyl methacrylate (DMAEMA), the hydrophobic monomer methyl methacrylate (MMA), and the hydrophobic cross-linker ethylene glycol dimethacrylate (EGDMA) were prepared using group transfer polymerization in a two-step procedure that involved the synthesis of linear polyDMAEMA or polyMMA arms, followed by their cross-linking using a mixture of EGDMA with either MMA or DMAEMA, respectively. Four semisegmented APCNs with polyMMA arms with degrees of polymerization (DPs) of 10, 20, 30, and 40 and three with polyDMAEMA arms with DPs of 10, 20, and 30 were prepared. The sol fraction extracted from the APCNs, the percentage of linear polymer in the sol fraction, and the molecular weights of the branched fraction of the extractables increased as the DP of the arms increased. The degrees of swelling (DSs) in water of all semisegmented APCNs increased with decreasing pH and increasing percentage of DMAEMA hydrophilic units. Despite the rather imperfect, semisegmented placement of the dissimilar units, extensive small-angle neutron scattering (SANS) experiments in D2O indicated that nanophase organization did take place within these APCNs and persisted, in many cases, even at full ionization of the hydrophilic monomer repeating units. The SANS profiles were also used to calculate the spacings between the scattering centers, which were found to increase with the content in the DMAEMA units and their degree of ionization. © 2009 American Chemical Society. 42 8 2972 2980 Cited By :24

A hydrolyzable dimethacrylate cross-linker, 2-methyl-2,4-pentanediol dimethacrylate (MPDMA), was synhesized by the reaction of 2-methyl-2,4-pentanediol and methacryloyl chloride in the presence of triethylamine. This cross-linker was used to prepare a neat cross-linker network and three cross-linked star polymer model networks (CSPMNs) of methyl methacrylate (MMA), as well as star-shaped polymers of MMA, by group transfer polymerization (GTP). Gel permeation chromatography (GPC) in tetrahydrofuran (THF) confirmed the narrow molecular weight distributions (MWDs) of the linear polymer precursors, and demonstrated the increase in molecular weight (MW) on each successive addition of cross-linker or monomer. Characterization of the star polymers by static light scattering (SLS) in THF showed that star polymers with MPDMA cores bear a relatively small number of arms, between 7 and 35. All star polymers and polymer networks containing the MPDMA cross-linker were hydrolyzed at room temperature in neat trifluoroacetic acid to yield lower-MW products. © 2006 American Chemical Society. 18 1 85 93 Cited By :33

The aim was to estimate the dietary aflatoxin B1 (AFB1) intake of the adolescent population in Cyprus, to compare this exposure estimate with the BMDL10 intake value of 0.17 μg/kg b.w. per day for carcinogenicity in animals and to calculate the contribution rate of the major food groups to the AFB1 exposure. AFB1 occurrence data in food (n=1231) for 2005-2013 were used. The mean and 95th percentile dietary intake values, based on mean AFB1 concentrations, were 0.001 and 0.002 μg/kg b.w. per day, respectively. These values are much lower than the BMDL10 value. At the same time, the MOE values are much less than 10000, even if we take into account the BMDL10 of 0.87 μg/kg b.w per day for carcinogenicity in humans, so the current levels of exposure are of public health concern. Nevertheless, MOE is just an indicative measure of risk and it does not substitute the ALARA (As Low As Reasonably Achievable) principle. The food group “Legumes bean dried”, which includes peanuts, contributed 33.8% to overall AFB1 exposure, followed by grain products (28.6%) and spices (26.1%)., CY; el; efsafocalpoint@sgl.moh.gov.cy

This study uses standard synthetic methodologies to produce tissue-mimicking materials that match the morphology and emulate the in vivo murine and human cardiac mechanical and imaging characteristics, with dynamic mechanical analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM) and magnetic resonance imaging. In accordance with such aims, poly(glycerol sebacate) (PGS) elastomeric materials were synthesized (at two different glycerol (G)-sebacic (S) acid molar ratios the first was synthesized using a G:S molar ratio of 2:2, while the second from a 2:5 G:S molar ratio, resulting in PGS2:2 and PGS2:5 elastomers, respectively). Unlike the synthesized PGS2:2 elastomers, the PGS2:5 materials were characterized by an overall mechanical instability in their loading behavior under the three successive loading conditions tested. An oscillatory response in the mechanical properties of the synthesized elastomers was observed throughout the loading cycles, with measured increased storage modulus values at the first loading cycle, stabilizing to lower values at subsequent cycles. These elastomers were characterized at 4°C and were found to have storage modulus values of 850 and 1430 kPa at the third loading cycle, respectively, in agreement with previously reported values of the rat and human myocardium. SEM of surface topology indicated minor degradation of synthesized materials at 10 and 20 d post-immersion in the PBS buffer solution, with a noted cluster formation on the PGS2:5 elastomers. AFM nanoindentation experiments were also conducted for the measurement of the Young modulus of the sample surface (no bulk contribution). Correspondingly, the PGS2:2 elastomer indicated significantly decreased surface Young's modulus values 20 d post-PBS immersion, compared to dry conditions (Young's modulus = 1160 ± 290 kPa (dry) and 200 ± 120 kPa (20 d)). In addition to the two-dimensional (2D) elastomers, an integrative platform for accurate construction of three-dimensional tissue-mimicking models of cardiac anatomy from 2D MR images using rapid prototyping manufacturing processes was developed. For synthesized elastomers, doping strategies with two different concentrations of the MRI contrast agent Dotarem allowed independent and concurrent control of the imaging characteristics (contrast and relaxivity) during the synthetic process for increased contrast agent absorption, with tremendous potential for non-destructive in vivo use and applications to cardiovascular and cerebrovascular diseases. © 2012 IOP Publishing Ltd. 7 3 Cited By :5

Five linear amphiphilic multiblock copolymers based on 2-(dimethylamino) ethyl methacrylate ("D") and methyl methacrylate ("M"), bearing from two to six blocks, were synthesized using sequential group transfer polymerization. All copolymers were obtained from the same polymerization flask (by the withdrawal of a sufficient amount of sample and appropriate adjustment of subsequent monomer loadings) to ensure better comparison between the various multiblocks. A theoretical degree of polymerization (DPth) of 20 was targeted for all D blocks, whereas a DPth of 10 was aimed for the M blocks. Upon characterization using gel permeation chromatography and H NMR spectroscopy, the copolymers were confirmed to have the expected values of molecular weights and compositions. Subsequently, the aqueous micellization behavior of these copolymers was probed using dye solubilization, dynamic light scattering, and small-angle neutron scattering. Dye solubilization experiments indicated that micelles readily formed at low copolymer concentrations equal to or less than 0.03% w/w. The scattering measurements revealed that despite the differences in their overall DPth values, the triblock, the tetrablock, and the pentablock copolymers selfassembled in water to form micelles with radii of gyration and hydrodynamic radii very similar to each other, suggesting chain looping and the formation of flowerlike micelles, which is in agreement with recent Monte Carlo simulations. © 2009 American Chemical Society. 42 15 5492 5498 Cited By :28

Large-core star polymers (LCSPs) and polymer networks were prepared using sequential group transfer polymerization (GTP) for the synthesis of linear poly(methyl methacrylate) (polyMMA) arms, followed by their cross-linking using a mixture of MMA monomer and ethylene glycol dimethacrylate (EGDMA) cross-linker. High monomer/cross-linker molar ratios and short arms favored the formation of polymer networks, whereas the opposite conditions favored the formation of LCSPs. LCSPs presented two populations: star polymers and covalently linked star polymer aggregates. The size of the non-aggregated star polymers, and the size and fraction of the star polymer aggregates passed through a maximum as the amount of the monomer in the cross-linking mixture increased. The degrees of swelling in tetrahydrofuran (THF) of the networks, the sol fraction extracted from them, and the percentage of linear polymer in the sol fraction increased as the degree of polymerization of the arms increased. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA,. 210 5 367 376 Cited By :6

Group transfer polymerization was used to prepare hydrophilic, cationic large-core star polymers (LCSPs) and networks of 2-(dimethylamino)ethyl methacrylate (DMAEMA) and ethylene glycol dimethacrylate (EGDMA) in a two-step procedure involving the synthesis of linear DMAEMA arms, followed by their crosslinking using a mixture of DMAEMA monomer and EGDMA crosslinker. The degree of polymerization of the linear chains prepared in the first step was kept constant, while the composition of the crosslinking mixture was varied systematically at a constant amount of crosslinker. The monomer/crosslinker molar ratio determined whether LCSPs or polymer networks would be produced. In particular, a high monomer/crosslinker molar ratio led to the formation of networks, whereas LCSPs were formed when a low monomer/crosslinker molar ratio was used. The absolute weight-average molecular weight of the LCSPs was determined using static light scattering, whereas their hydrodynamic radii and radii of gyration were determined using dynamic light scattering and small-angle neutron scattering, respectively. The sol fraction extracted from the networks decreased as the monomer/crosslinker molar ratio increased. The degrees of swelling of all of the networks were measured as a function of pH and were found to increase below pH 7. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3958–3969, 2008