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18,774 result(s) for "Bisphenol A"
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Ten bisphenol analogues in Chinese fresh dairy milk: high contribution ratios of conjugated form, importance of enzyme hydrolysis and risk evaluation
This study investigated concentration levels of ten bisphenols (BPs) in 13 Chinese commercial fresh low temperature dairy milk samples (fresh milk) of main local and national brands with or without enzyme hydrolysis. The results showed that at least two BPs were detected in each fresh milk sample without enzyme hydrolysis and the respective mean concentrations of bisphenol AF (BPAF), bisphenol B (BPB), bisphenol C (BPC), bisphenol F (BPF), bisphenol A (BPA), bisphenol S (BPS), bisphenol AP (BPAP), bisphenol PP (BPP), bisphenol Z (BPZ), and bisphenol E (BPE) were 0.73, 0.61, 1.86, 0.87, 0.42, 0.11, 1.06, 1.42, 1.5, and 0.04 ng/mL, while their respective detection frequencies ranged from 23.1–92.3%. These results indicated the frequent detection of BPs in fresh milk samples. With enzyme hydrolysis, the respective mean concentrations of BPAF, BPA, BPB, BPC, BPF, BPS, and BPAP were increased 7.1–107.1%, indicating the long-ignored importance of enzyme hydrolysis. The respective average estimated daily intakes (EDIs) of BPA by adult and children in China via fresh milk were 32.5 and 37.5 ng/kg bw/d, indicating that BPA in fresh milk was a crucial source to human. Six out of nine other BPs had higher average EDIs than that of BPA, among which the EDI of BPAP was almost three times that of BPA, suggesting the widespread contamination of other BPs in Chinese fresh milk.
Removal of Bisphenol A and Its Potential Substitutes by Biodegradation
The possibility of removing bisphenol A and its five potential substitutes (bisphenols S, F, AF, E, and B) was tested using microorganism consortia from river water and activated sludge from municipal and rural wastewater treatment plants. For most bisphenols, biodegradation with activated sludge was faster than with river water and a greater extent of biodegradation was also achieved. However, only bisphenol A and bisphenol F underwent 100% primary biodegradation while other bisphenols degraded no more than about 50% which has some important implications in case of their increased usage. Metabolic activity in biodegradation liquors was also tested and it showed higher activity in the tests with activated sludge than with river water. However, there was no clear connection between the decline of metabolic activity and the extent of biodegradation as decreased activity was observed for two easily degrading bisphenols and two others with little biodegradability. It can be assumed that two different phenomena are involved in this process including depletion of nutrients for easily degradable bisphenol A and absence of nutrients for bacteria incapable of primary degradation of bisphenol AF and bisphenol S.
Human exposure of bisphenol A and its analogues: understandings from human urinary excretion data and wastewater-based epidemiology
This work evaluated human exposure to bisphenol A (BPA) and its analogues based on human urinary excretion data and wastewater-based epidemiology (WBE). The results showed that the world’s average human daily intake ranked from high to low is in order of bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), bisphenol P (BPP), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol Z (BPZ), and bisphenol AF (BPAF), and their corresponding human daily intakes are 2.53, 0.68, 0.60, 0.41, 0.36, 0.29, 0.24, and 0.06 μg/p/day, respectively. BPA is clearly the dominant bisphenol for human exposure. However, the results also showed that humans have been widely exposed to BPA analogues as well. Many BPA analogues showed similar estrogenic activities to those of BPA; therefore, the adverse effects of BPA and its analogues on humans should be comprehensively evaluated. The nominal exposure levels obtained based on wastewater-based epidemiology ranked high to low are in order of BPA (513.73 μg/p/day), BPF (10.20 μg/p/day), BPS (5.21 μg/p/day), BPP (1.15 μg/p/day), BPZ (0.66 μg/p/day), BPB (0.61 μg/p/day), BPAF (0.58 μg/p/day), and BPAP (0.35 μg/p/day). The world’s human average daily intakes of BPA and its analogues are only 0.5–47.9% of the intakes of their corresponding human nominal exposures. This study suggests that other sources rather human excretions are important origins in municipal wastewater, which indicates that the WBE method based on parent compounds is inappropriate for evaluations of human daily intakes of BPA and its analogues, neither for other industrial compounds that have multiple important sources. Three main important sources of BPA and its analogues in municipal wastewater are likely effluents of industrial wastewater, discharges of hospital wastewater, and landfill leachates. To decrease discharges of BPA and its analogues to the natural environment, any mixing of industrial and hospital wastewater as well as landfill leachates in municipal wastewater is not favorable.
Maternal bisphenol urine concentrations, fetal growth and adverse birth outcomes: A population-based prospective cohort
Background Exposure to bisphenols may affect fetal growth and development. The trimester-specific effects of bisphenols on repeated measures of fetal growth remain unknown. Our objective was to assess the associations of maternal bisphenol urine concentrations with fetal growth measures and birth outcomes and identify potential critical exposure periods. Methods In a population-based prospective cohort study among 1379 pregnant women, we measured maternal bisphenol A, S and F urine concentrations in the first, second and third trimester. Fetal head circumference, length and weight were measured in the second and third trimester by ultrasound and at birth. Results An interquartile range increase in maternal pregnancy-averaged bisphenol S concentrations was associated with larger fetal head circumference (difference 0.18 (95% confidence interval (CI) 0.01 to 0.34) standard deviation scores (SDS), p -value< 0.05) across pregnancy. When focusing on specific critical exposure periods, any detection of first trimester bisphenol S was associated with larger second and third trimester fetal head circumference (difference 0.15 (95% CI 0.05 to 0.26) and 0.12 (95% CI 0.02 to 0.23) SDS, respectively) and fetal weight (difference 0.12 (95% CI 0.02 to 0.22) and 0.16 (95% CI 0.06 to 0.26) SDS, respectively). The other bisphenols were not consistently associated with fetal growth outcomes. Any detection of bisphenol S and bisphenol F in first trimester was also associated with a lower risk of being born small size for gestational age (Odds Ratio 0.56 (95% CI 0.38 to 0.74) and 0.55 (95% CI 0.36 to 0.85), respectively). Bisphenols were not associated with risk of preterm birth. Conclusions Higher maternal bisphenol S urine concentrations, especially in the first trimester, seem to be related with larger fetal head circumference, higher weight and a lower risk of being small size for gestational age at birth.
Bisphenol A substitutes and childhood obesity at 7 years: a cross-sectional study in Shandong, China
Bisphenol A (BPA) substitutes, such as bisphenol S (BPS) and bisphenol AF (BPAF), are increasingly used due to restrictions on BPA usage, a known endocrine disrupting chemical and putative obesogen. However, little is known about the obesogenic effects of exposure to BPA substitutes in children. A total of 426 children aged 7 years old originally recruited from Laizhou Wan Birth Cohort in Shandong, China, during 2010–2013 participated in the 2019–2020 survey. Urinary BPA and its substitutes including BPS, BPAF, bisphenol B (BPB), bisphenol AP (BPAP), bisphenol Z (BPZ), and bisphenol P (BPP) were determined. Anthropometric measures including height, weight, waist circumference, and body fat percentage were assessed, and overweight/obesity was defined as BMI z -score ≥ 85th percentile. Linear and logistic regressions were used on continuous and binary obesity measures, respectively, and weighted quantile sum (WQS) regression was further used to estimate the mixture effects of exposure to diverse bisphenols, and sex-stratified analysis was performed. BPA substitutes were widely detected (> 75%) in children’s urine samples. A positive association with obesity measures was consistently observed for urinary BPS and BPAF, i.e., BMI z -score, waist circumference, and overweight/obesity. Further analysis from the WQS regression model demonstrated a positive association between bisphenol mixtures and all measures of obesity, with BPAF contributing the greatest weighing to the observed associations. Sex difference might exist as the positive associations were only significant in boys. No significant association was found between obesity and BPA or other BPA substitutes. Our study adds to mounting evidence that BPA substitutes BPS and BPAF are linked to obesity in children, especially in boys. Further longitudinal studies with larger sample size with continued biomonitoring these chemicals and their obesogenic effects are necessary.
Toxicity and bioconcentration of bisphenol A alternatives in the freshwater pulmonate snail Planorbella pilsbryi
Bisphenol A (BPA) is an industrial chemical identified as a vertebrate endocrine disruptor. Numerous alternatives have been developed, for which toxicity data are lacking. The present study assessed the toxicity of BPA and its replacement products bisphenol F (BPF), bisphenol S (BPS), and bisphenol AF (BPAF) in freshwater snail ( Planorbella pilsbryi ) embryos and adults. The chronic toxicity of BPA and BPAF was further characterized in 28-day tests with adult snails, followed by 21-day assessments of hatching and survival of embryos produced at the end of the test (F1 generation). In acute tests, BPAF was the most toxic of the substances tested (maximum acceptable toxicant concentration [MATC], 136 µg/L), followed by BPA (MATC, 1404 µg/L), BPF (MATC, 1525 µg/L), and BPS (MATC > 8590 µg/L). In the chronic test with BPA, although we observed no significant effects on adult snails up to 479 µg/L, the hatching and survival of juveniles from the F1 generation decreased (MATC, 13 µg/L), and was delayed by 7.5 days, on average. In contrast, we did not observe any decrease in hatching or survival of juveniles from the F1 generation during exposure to BPAF. Effects were observed at concentrations above most reported environmental exposure concentrations, although there was an overlap between exposure and effect concentrations. Given that concentrations of alternative substances are expected to increase, and in the absence of data on potential effects of mixtures, further research is needed.
Exposure to Bisphenol A Substitutes, Bisphenol S and Bisphenol F, and Its Association with Developing Obesity and Diabetes Mellitus: A Narrative Review
Bisphenol A, a well-known endocrine-disrupting chemical, has been replaced with its analogs bisphenol S (BPS) and bisphenol F (BPF) over the last decade due to health concerns. BPS and BPF are present in relatively high concentrations in different products, such as food products, personal care products, and sales receipts. Both BPS and BPF have similar structural and chemical properties to BPA; therefore, considerable scientific efforts have investigated the safety of their exposure. In this review, we summarize the findings of relevant epidemiological studies investigating the association between urinary concentrations of BPS and/or BPF with the incidence of obesity or diabetes. The results showed that BPS and BPF were detected in many urinary samples at median concentrations ranging from 0.03 to 0.4 µg·L−1. At this exposure level, BPS median urinary concentrations (0.4 µg·L−1) were associated with the development of obesity. At a lower exposure level (0.1–0.03 µg·L−1), two studies showed an association with developing diabetes. For BPF exposure, only one study showed an association with obesity. However, most of the reported studies only assessed BPS exposure levels. Furthermore, we also summarize the findings of experimental studies in vivo and in vitro regarding our aim; results support the possible obesogenic effects/metabolic disorders mediated by BPS and/or BPF exposure. Unexpectedly, BPS may promote worse obesogenic effects than BPA. In addition, the possible mode of action underlying the obesogenic effects of BPS might be attributed to various pathophysiological mechanisms, including estrogenic or androgenic activities, alterations in the gene expression of critical adipogenesis-related markers, and induction of oxidative stress and an inflammatory state. Furthermore, susceptibility to the adverse effects of BPS may be altered by sex differences according to the results of both epidemiological and experimental studies. However, the possible mode of action underlying these sex differences is still unclear. In conclusion, exposure to BPS or BPF may promote the development of obesity and diabetes. Future approaches are highly needed to assess the safety of BPS and BPF regarding their potential effects in promoting metabolic disturbances. Other studies in different populations and settings are highly suggested.
Multi-residue Determination of Bisphenol Compounds in Feed Using Ultrasound-Assisted Extraction and Dispersive Solid-Phase Extract Followed by High-Performance Liquid Chromatography with Fluorescence Detector
Monitoring of bisphenols (BPs) in feed is a necessary process for the security of food of animal origin. In this study, a method was established to simultaneously detect bisphenol A (BPA), bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bisphenol F (BPF), bisphenol AP (BPAP), bisphenol Z (BPZ), bisphenol P (BPP) and bisphenol PH (BPPH) in feed. A simple and rapid pretreatment procedure was developed using ultrasound-assisted extraction (UAE) and dispersive solid-phase extraction (DSPE), and then the prepared sample was analysed by high-performance liquid chromatographic (HPLC) with fluorescence detector (FLD). Finally, the operating conditions of UAE, DSPE, and HPLC were all optimised to increase the sample throughput and sensitivity. Under the optimized conditions, good linearities were obtained for nine BPs with the correlation coefficients (R2) above 0.995; the recoveries of nine BPs in spiked feed samples were in the range of 82.56–103.87% and relative standard deviations (RSDs) were in the range of 2.4–13.40%; the limits of detections (LODs) and quantitations (LOQs) were in the range of 1.0–5.0 and 3.3–16.6 μg kg − 1, respectively. The results clearly demonstrated the developed method provided the reliable screening and quantification of nine BPs in feed and possessed the advantages including low cost, quick, and simple.Graphic abstract
Quasilinear Evolution Equations in L.sup.P.sub.mu-Spaces with Lower Regular Initial Data
We study the Cauchy problem of the quasilinear evolution equations in [L.sup.P.sub.[mu]]-spaces. Based on the theories of maximal [L.sup.p]-regularity of sectorial operators, interpolation spaces, and time-weighted [L.sup.p]-spaces, we establish the local posedness for a class of abstract quasilinear evolution equations with lower regular initial data. To illustrate our results, we also deal with the second-order parabolic equations and the Navier-Stokes equations in [L.sup.p,q]-spaces with temporal weights.