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Abstract The plasticizer bisphenol-A (BPA) is common to municipal wastewaters and can exert toxicity to exposed organisms in the environment. Here BPA concentration at 5 sewage treatment works (STW) and distribution throughout a river catchment in South West UK were investigated. Sampling sites included influent and effluent wastewater (n = 5), river water (n = 7) and digested sludge (n = 2) which were monitored for 7 consecutive days. Findings revealed average BPA loads in influent wastewater at two STWs were 10–37 times greater than the other wastewaters monitored. Concentrations up to ~100 μg L−1 were measured considerably higher than previously reported for municipal wastewaters. Temporal variability throughout the week (i.e., highest concentrations during weekdays) suggests these high concentrations are linked with industrial activity. Despite ≥90% removal during wastewater treatment, notable concentrations remained in tested effluent (62–892 ng L−1). However, minimal impact on BPA concentrations in river water was observed for any of the effluents. The maximum BPA concentration found in river water was 117 ng L−1 which is considerably lower than the current predicted no effect concentration of 1.6 μg L−1. Nevertheless, analysis of digested sludge from sites which received these elevated BPA levels revealed average concentrations of 4.6 ± 0.3 and 38.7 ± 5.4 μg g−1. These sludge BPA concentrations are considerably greater than previously reported and are attributed to the high BPA loading in influent wastewater. A typical sludge application regime to agricultural land would result in a predicted BPA concentration of 297 ng g−1 in soil. Further studies are needed on the toxicological thresholds of exposed terrestrial organisms in amended soils to better assess the environmental risk here. Graphical abstract Unlabelled Image Highlights • Comprehensive study of BPA in the water cycle reported. • Industrial discharges of BPA in municipal wastewater identified through wastewater analysis. • Considerable temporal and spatial variability of BPA loads in wastewater. • Effluent discharges had little impact to river quality and levels below current PNEC. • High BPA concentrations (4.6 and 38.7 μg g−1) in digested sludge for land application. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol-A (BPA) possesses estrogenic properties both in vitro and in vivo as an endocrine disrupting chemical. Humans experience a long-term and cumulative exposure to BPA. BPA was detectable in 97.3% of 1904 urine specimens from Korean adults. We investigated urinary estrogen concentrations in subjects with low and high BPA concentrations and its possible association with estrogen metabolism. Urine samples were collected from a high BPA concentration group (BPA-H; n=100, 11.05±20.47μg/g creatinine) and a low BPA concentration group (BPA-L; n=100, 0.70±0.22μg/g creatinine) from Korea Biomonitoring Program of Hazardous Materials Survey 2009–2010. Urinary estrogens were enzymatically hydrolyzed, extracted, and then derivatized for quantitative analysis by gas chromatography–mass spectrometry. Estrogen levels were higher in the BPA-H group than in the BPA-L group. Concentrations of estrone, 17β-estradiol, and their hydroxylated metabolites in both men and women were significantly higher in the BPA-H group than in the BPA-L group (p<0.04). Furthermore, in the BPA-H group, estrogen metabolism to 4-hydroxy-estrone and 4-hydroxy-17β-estradiol was more active than that to 2-hydroxy-estrone and 2-hydroxy-17β-estradiol. Although single measurement and/or single spot urine samples limit the measurement of long-term exposure to BPA, we found significant differences of estrogen metabolism in the BPA-H and the BPA-L groups. The increase of hydroxyestrogens, especially 4-hydroxyestrogens, can be an important factor resulting negative effects of prolonged exposure to BPA. [Copyright &y& Elsevier]

Abstract: Occurrence and methods for the removal of nonylphenolic compounds in drinking water have been gaining increased attention due to their widespread presence in natural water and the potential health risks from the consumptions of drinking water. The purpose of this study was to assess the occurrence of nonylphenol (NP), octylphenol (OP), and bisphenol-A (BPA) in water sources and treated water in Taiwan, to evaluate the treatment efficiencies of these compounds in both the conventional (coagulation, sedimentation, filtration and chlorination) and advanced treatment processes. The treatment efficiencies of these chemicals were assessed based on their concentrations in water sources, and the results were verified with laboratory simulated treatment processes. A survey of NP, OP, and BPA in 11 Taiwanese water sources showed that all of them could be identified in most of the sampled sources, and that higher concentrations of NP were found when the raw water was contaminated by domestic wastewater. However, higher treatment efficiency could be observed when the NP concentration in water source is high. Laboratory simulation studies of conventional treatment processes showed that chlorination played an important role in the degradation of NP in raw water. Treatment efficiencies of 60%–90% were achieved for NP removal when sufficient chlorine dosages were applied to satisfy chlorine demands. However, results also showed that conventional coagulation and rapid filtration processes were less effective in the reduction of phenolic compounds in water. [Copyright &y& Elsevier]

Abstract: Bisphenol-A (BPA) is a commonly used color developer in thermal paper. In this application, BPA is present in its free, unbound form and can be readily released, making thermal paper a potential source for human exposure. In this study, BPA was determined in 44 thermal paper samples collected in Belgium. BPA was detected in all the samples; 73% of the samples had concentrations between 0.9% and 2.1% (between 9 and 21mg BPA/g paper), while the remaining 27% of the samples had concentrations below 0.01% (0.1mg BPA/g paper). The BPA concentrations measured in thermal paper were comparable with those reported in other international studies. Since thermal paper is a feedstock for paper recycling processes, contamination of other “BPA-free” papers can occur. An estimation of human exposure through thermal paper results in a median intake of 445ng BPA/day for the general population, which corresponds to an exposure of 6.4ng/kg bw/day for a person of 70kg. The exposure of those people who come occupationally in contact with thermal paper can be much higher. [Copyright &y& Elsevier]

A multilayered iron oxide/reduced graphene oxide (ION-RGO) nanocomposite electrode is reported for the voltammetric sensing of bisphenol-A (BPA). Structural characterizations reveal the nanocomposite features RGO sheets decorated with nanometric spherical ION in a mixture of maghemite and magnetite phases. ITO substrate modified with the ION-RGO multilayered film exhibits strong electrocatalytic effect toward BPA oxidation, which is made possible by Fe(III) catalysts generated at the ION's surface after scanning the electrode potential from below 0 V (vs Ag/AgCl) and followed by the RGO phase conducting the transferred electrons. Under optimized differential pulse voltammetry conditions, the proposed sensor shows three linear working ranges 0.09–1.17 (r2 = 0.999), 1.17–3.81 (r2 = 0.995) and 3.81–8.20 (r2 = 0.998), with the highest sensitivity equaling 7.76 μA cm−2/μmol L−1 and the lowest limit of detection of 15 nmol L−1. A single electrode can be used for at least twenty consecutive runs loosing less than 15% of sensitivity, whereas electrodes fabricated in different bacthes exhibit almost identical perfomances. Determination of BPA in a thermal paper sample shows no difference (at 95% confidence level) between the proposed sensor and HPLC/UV. The sensor is neither influenced by the matrix composition nor by other emerging contaminants. Unlabelled Image • ION-RGO electrode exhibiting electrocatalytic effect toward BPA oxidation • Detection is insensitive to the matrix composition and other emerging contaminants. • Electrode can be used for twenty consecutive runs without losing sensitivity. • Low-cost and reproducible electrode fabrication process • Analytical performance comparable to HPLC/UV [ABSTRACT FROM AUTHOR]

• BPA inhibited fatty acid uptake and oxidative decomposition in the liver. • BPA promoted fatty acid synthesis and aerobic glycolysis. • BPA blocked anaerobic glycolysis, gluconeogenesis and the TCA cycle. • BPA upregulated the liver nuclear receptor, LXR, in mice. • BPA induced hypoglycemia occurred through LXR-inhibited hepatic gluconeogenesis and inhibition of glycogen decomposition. Bisphenol-A (BPA) is a representative environmental endocrine disrupting chemical that is widely used in the production of polycarbonate plastics and epoxy resins. Many studies have confirmed BPA to be closely associated with metabolic diseases, reproductive system diseases, and sex hormone-dependent cancers. In this study, we aimed to systematically elucidate the molecular action of BPA on liver fatty acid and glucose metabolism and the reasons for BPA-induced hypoglycemia through a metabonomics approach. C57BL/6 mice were orally treated with BPA (1, 10, 50, 250 μg/kg) for 35 days and the liver metabonomics and histopathology, molecular docking, mRNA expression levels and activities of enzymes were analyzed. Based on the high-resolution mass spectrometry (MS) for metabonomics and on various software and bioinformatic analysis methods, we found that BPA could affect fatty acid and glucose metabolism, block the TCA cycle, and BPA also regulated the nuclear receptor LXR caused hypoglycemia, thereby affecting the normal metabolic functions of the liver. [ABSTRACT FROM AUTHOR]