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Bisphenol A and its analogues belong to the class of endocrine disrupting chemicals, massively employed by industries to produce polycarbonate and epoxy resins, designed to be in direct contact with foodstuffs. Their leaching from the canned packaging into its content results in food contamination. This review aims at offering a country-specific overview of the occurrence of bisphenols in six main categories of foodstuff marketed in the EU, based on monitoring studies performed in the 27 EU countries for which data are available and prevalently published in the last five years. The general overview of the literature data shows that concentration values of BPs detected into foodstuff is lower in Northern Europe than Southern Europe. A probable daily intake was hypothesized for some countries to provide an EU population exposure assessment. The consumption of canned meat and vegetables is responsible of PDI values higher than those of other food categories. These data emphasize that food and beverage monitoring should deserve greater attention especially by European countries for which no studies are available and especially with regards to bisphenols other than BPA whose limits are not set by the European regulations and whose toxicity has not been fully established.

Bisphenol A (BPA) is a xenobiotic endocrine-disrupting chemical.In vitroandin vivostudies have indicated that BPA alters endocrine-metabolic pathways in adipose tissue, which increases the risk of metabolic disorders and obesity. BPA can affect adipose tissue and increase fat cell numbers or sizes by regulating the expression of the genes that are directly involved in metabolic homeostasis and obesity. Several studies performed in animal models have accounted for an obesogen role of BPA, but its effects on human adipocytes – especially in children – have been poorly investigated. The aim of this study is to understand the molecular mechanisms by which environmentally relevant doses of BPA can interfere with the canonical endocrine function that regulates metabolism in mature human adipocytes from prepubertal, non-obese children. BPA can act as an estrogen agonist or antagonist depending on the physiological context. To identify the molecular signatures associated with metabolism, transcriptional modifications of mature adipocytes from prepubertal children exposed to estrogen were evaluated by means of microarray analysis. The analysis of deregulated genes associated with metabolic disorders allowed us to identify a small group of genes that are expressed in an opposite manner from that of adipocytes treated with BPA. In particular, we found that BPA increases the expression of pro-inflammatory cytokines and the expression ofFABP4andCD36, two genes involved in lipid metabolism. In addition, BPA decreases the expression ofPCSK1, a gene involved in insulin production. These results indicate that exposure to BPA may be an important risk factor for developing metabolic disorders that are involved in childhood metabolism dysregulation.

A fluidized bed reactor, filled with laccase-based beads, has been employed to bioremediate aqueous solutions polluted by endocrine disruptors belonging to the alkylphenols (APs) class. In particular Octylphenol and Nonylphenol have been studied. The catalytic activity of free and immobilized laccase from Trametes versicolor has been characterized as a function of pH, temperature and substrate concentration in the reaction medium. In view of practical applications for each substrate concentration the removal efficiency (RE), the time to halve the initial concentration (tau(50)), and the t(c-0), i.e. the time to reach complete pollutant removal, have been calculated. The immobilized laccase exhibited a lower affinity for octylphenol (K-m = 1.11 mM) than for Nonylphenol (K-m = 0.72 mM), but all the other parameters of applicative interest resulted more significant for octylphenol. For example, the times to reach the complete removal of octylphenol compared to those for nonylphenol at the same concentration is shorter of about 15% (at low concentrations) up to 40% (at high concentrations). The study of cell proliferation with MPP89 cells, a human mesothelioma cell line, and the assay with the YES test indicated the loss of estrogenic activity of the APs solutions after laccase treatment. (C) 2013 Elsevier B.V. All rights reserved.

Pregnant adult Balb-C mice were exposed daily to two different doses of Bisphenol A (BPA) by subcutaneous injection beginning on gestational day 1 through the seventh day after delivery. The mothers were sacrificed on postpartum day 21, and the offspring were sacrificed at 3 months of age. Control mice were subjected to the same experimental protocol but received saline injections. The liver, muscles, hindbrain and forebrain of the offspring were dissected and processed using HPLC to assess the level of BPA in the tissues and to determine its dependence on the exposure dose and gender. For comparison, the same tissues were dissected from the mothers and analysed. We report the following results: (1) the level of BPA that accumulated in a given tissue was dependent on the exposure dose; (2) the rank order of BPA accumulation in the various tissues was dependent on the gender of the offspring; (3) the average BPA concentrations in the liver and muscle of the female offspring were higher than in the males; and (4) the average BPA concentration in the central nervous system (i.e., the hindbrain and forebrain) of the male offspring was higher than in the females. (C) 2011 Elsevier B.V. All rights reserved.

The oxidative biodegradation of 2- and 4-chlorophenol (CPs) catalyzed by immobilized laccase from Trametes versicolor was conducted in a bed reactor. The effects of reaction conditions (reaction time, dosage of immobilized enzyme, flow rate, pH value and temperature, initial concentration) on CPs removal efficiency (RE) were investigated. By using in the immobilization solution an enzyme dosage of 2.5 mg free enz g carrier − 1 , the maximum ratio of laccase to PAN-beads is resulted 0.25 mg imm enz g carrier − 1 . RE values greater than 70% were obtained when 40 mL of 1 mM substrate solution were circulated for 90 min at 75 mL min−1 in the bed reactor filled with 12 g of laccase-PAN beads. The optimal pH for CPs biodegradation was 5 and it was not related to substituent position on aromatic ring. Experiments with immobilized laccase demonstrated good removal at high initial substrate concentrations and high thermal stability. The affinity of 2-CP was higher than that of 4-CP. Finally, the 2-CP was also biodegraded as tertiary mixtures with 2,3,4,5-tetrachlorophenol (TCP) and pentachlorophenol (PCP). The presence of TCP and PCP decreased the removal efficiency of 2-CP. The order of the relative degrading capacity becomes TCP > PCP > 2-CP.