Bisphenol AF (BPAF) is a fluorinated analog of bisphenol A (BPA), and it is a more potent estrogen receptor (ER) agonist. BPAF is mainly metabolized to BPAF-glucuronide (BPAF-G), which has been ...reported to lack ER agonist activity and is believed to be biologically inactive. The main goal of the current study was to examine the influence of the metabolism of BPAF via glucuronidation on its ER activity and adipogenesis. Also, as metabolites can have different biological activities, the effects of BPAF-G on other nuclear receptors were evaluated. First, in-vitro BPAF glucuronidation was investigated using recombinant human enzymes. Specific reporter-gene assays were used to determine BPAF and BPAF-G effects on estrogen, androgen, glucocorticoid, and thyroid receptor pathways, and on PXR, FXR, and PPARγ pathways. Their effects on lipid accumulation and differentiation were determined in murine 3T3L1 preadipocytes using Nile Red, with mRNA expression analysis of the adipogenic markers adiponectin, Fabp4, Cebpα, and PPARγ. BPAF showed strong agonistic activity for hERα and moderate antagonistic activities for androgen and thyroid receptors, and for PXR. BPAF-G was antagonistic for PXR and PPARγ. BPAF (0.1 μM) and BPAF-G (1.0 μM) induced lipid accumulation and increased expression of key adipogenic markers in murine preadipocytes. BPAF-G is therefore not an inactive metabolite of BPAF. Further toxicological and epidemiological investigations of BPAF effects on human health are warranted, to provide better understanding of the metabolic end-elimination of BPAF.
•Influence of metabolism on BPAF endocrine activity and adipogenesis was studied.•BPAF is agonist on estrogen and antagonist on androgen, thyroid and PXR receptors.•BPAF glucuronide induced lipid accumulation and expression of adipogenic markers.•Glucuronidation of BPAF results in formation of biologically active metabolite.•Understanding metabolism of BPAF is important for risk assessment of BPAF.
Bisphenol A (BPA) is a ubiquitous chemical compound constantly being released into the environment, making it one of the most persistent endocrine-disrupting chemical (EDC) in nature. This EDC has ...already been associated with developing various pathologies, such as diabetes, obesity, and cardiovascular, renal, and behavioral complications, among others. Therefore, over the years, BPA has been replaced, gradually, by its analog compounds. However, these compounds are structurally similar to BPA, so, in recent years, questions have been raised concerning their safety for human health. Numerous investigations have been performed to determine the effects BPA substitutes may cause, particularly during pregnancy and prenatal life. On the other hand, studies investigating the association of these compounds with the development of cardiovascular diseases (CVD) have been developed. In this sense, this review summarizes the existing literature on the transgenerational transfer of BPA substitutes and the consequent effects on maternal and offspring health following prenatal exposure. In addition, these compounds' effects on the cardiovascular system and the susceptibility to develop CVD will be presented. Therefore, this review aims to highlight the need to investigate further the safety and benefits, or hazards, associated with replacing BPA with its analogs.
•Amount of BpA in its analogues can be determined by THz spectral processing method.•SVR is used to extract obscure properties from THz spectra of complex mixtures.•SVR in combination with THz-TDS ...can predict sample concentrations with R2 = 0.98.•Machine learning method is a forecast strategy for THz spectroscopic analysis.
Quantitative analysis of complex mixtures is a great challenge for spectral analysis. Bisphenol A (BpA) is a chemical predominantly used in manufacturing and is being replaced by other analogs due to its potential toxicity. Reliability methods is hence crucial for identification and quantification of bisphenol mixtures. In this study we present an attractive strategy for composition determination of BpA incorporated in its analogue mixtures. Terahertz spectra of four bisphenol components are analyzed using machine learning method (SVR) to learn the underlying model of the frequency against the target concentration of BpA in mixtures. The learned mode predicts the concentrations of the unknown samples with decision coefficient R2 = 0.98. Absorption spectra for bisphenols mixtures were successfully reconstructed by a hold-out validation scheme. The results indicate the terahertz spectroscopy in combination with SVR is robust and accurate in mixture quantitative analysis and should play a significant role for industrial applications in the future.
Bisphenols (BPs) are among emerging pollutants that have been frequently detected in different compartments of marine ecosystems and elicited great concern due to their potential toxicity to marine ...organisms. This work aimed to investigate the toxicity of bisphenol A (BPA) and bisphenol S (BPS) on oxidative stress markers, neurotoxicity and histopathological alterations in sea cucumbers (Holothuria poli). The results showed that exposure to 200 μg/L of BPA and BPS produced oxidative stress, neurotoxicity in the digestive tract and respiratory tree, and several types of histopathological lesions in tissues of the respiratory tree of the sea cucumber, posing a health hazard to this aquatic organism. In addition, BPA has greater effects than BPS on the generation of oxidative stress marked by the inductions of catalase (CAT), glutathione S-transferase (GST) and malondialdehyde (MDA) levels and neurotoxicity shown by the decrease in acetylcholinesterase activity (AChE). The respiratory tree of sea cucumbers might be an appropriate tissue for assessing CAT, MDA and AChE activity levels, which are reliable biomarkers that may be useful in marine biomonitoring studies. Evaluation of histopathological lesions of the respiratory tree suggests that BPA and BPS and their mixture cause various tissue alterations that may be associated with oxidative stress damage and neurotoxicity. In conclusion, this study showed that oxidative stress (CAT and MDA) and neurotoxicity (AChE) markers, as well as respiratory tree lesions, are sensitive biomarkers for the assessment of BPA and BPS toxicity in sea cucumbers.
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•Combined effects of BPA and BPS on biochemical responses of Holothuria poli were investigated.•BPA and BPS induced oxidative stress in exposed Holothuria poli.•BPA, BPS and BPA/BPS mixture altered the respiratory tree histological structure.•BPA/BPS mixture produced more pronounced effects than BPA and BPS alone.
Recent studies have reported that permanganate (Mn(VII)) shows a good performance in treatment of phenolic compounds, and the presence of iodide (I−) may display a great impact on Mn(VII) oxidation ...with the formation of toxic iodinated aromatic products. In this work, transformation of bisphenol AF (BPAF) and bisphenol S (BPS) by Mn(VII) in the absence or presence of I− was studied. Mn(VII) showed considerable reactivity towards BPAF with apparent second-order rate constants (0.09–1.65 M−1s−1) higher than those of Mn(VII) with BPS (0.02–0.12 M−1s−1) reported in literature over the pH range of 5–9. The presence of I− apparently accelerated the transformation rates of BPAF and BPS by Mn(VII), and these results could be explained by the contribution of hypoiodous acid (HOI) in situ formed from Mn(VII) oxidation of I−. A kinetic model involving the competitive reactions (i.e., Mn(VII) with I− and bisphenols, HOI with Mn(VII) and bisphenols) well simulated BPAF/BPS transformation by Mn(VII) in the presence of I− under various conditions. Hydroxylated, bond-cleavage, and polymeric products were identified from BPAF/BPS oxidation by Mn(VII), and iodinated aromatic products (e.g., mono- and multi-iodinated BPAF/BPS) were additionally detected in the presence of I−. Reaction pathways involving Mn(VII) one-electron oxidation as well as HOI substitution of BPAF/BPS were proposed. Eco-toxicity analysis by ECOSAR showed that the toxicity of these products generally followed the order of polymeric and iodinated aromatic products > parent BPAF/BPS > hydroxylated products > bond-cleavage products.
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•Mn(VII) displayed considerable reactivity towards BPAF and BPS.•The presence of I− apparently accelerated BPAF/BPS transformation by Mn(VII).•Mn(VII) oxidation of BPAF/BPS generated hydroxylated, bond-cleavage, and polymeric products.•Iodinated aromatic products were generated from BPAF/BPS oxidation by Mn(VII)/I− system.•Polymeric and iodinated aromatic products were more toxic than parent BPAF/BPS.
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► Synthesis of 3D BiOI/BiOCl microspheres by a one-pot template-free solvothermal method. ► Photocatalyst is BiOI/BiOCl composites. ► BiOI/BiOCl composites have enhanced visible-light ...photocatalytic ability to bisphenol-A. ► A simple and direct photodegradation pathway of bisphenol-A is proposed.
Three-dimensional (3D) BiOI/BiOCl composite microspheres with enhanced visible-light photodegradation activity of bisphenol-A (BPA) are synthesized by a simple, one-pot, template-free, solvothermal method using BiI3 and BiCl3 as precursors. These 3D hierarchical microspheres with heterojunction structures are composed of 2D nanosheets and have composition-dependent absorption properties in the ultraviolet and visible light regions. The photocatalytic oxidation of BPA over BiOI/BiOCl composites followed pseudo first-order kinetics according to the Langmuir–Hinshelwood model. The highest photodegradation efficiency of BPA, i.e., nearly 100%, was observed with the BiOI/BiOCl composite (containing 90% BiOI) using a catalyst dosage of 1gL−1 in the BPA solution (C0=20mgL−1, pH=7.0) under visible light irradiation for 60min. Under these conditions, the reaction rate constant was more than 4 and 20 times greater than that of pure BiOI and the commercially available Degussa P25, respectively. The superior photocatalytic activity of this composite catalyst is attributed to the suitable band gap energies and the low recombination rate of the photogenerated electron–hole pairs due to the presence of BiOI/BiOCl heterostructures. Only one intermediate at m/z 151 was observed in the photodegradation process of BPA by liquid chromatography combined with mass spectrometry (LC–MS) analysis, and a simple and hole-predominated photodegradation pathway of BPA was subsequently proposed. Furthermore, this photocatalyst exhibited a high mineralization ratio, high stability and easy separation for recycling use, suggesting that it is a promising photocatalyst for the removal of BPA pollutants.
Bisphenol-S (BPS) is a current substitute for Bisphenol-A (BPA) in various commercial products (paper, plastics, protective can-coatings, etc.) used by all age groups globally. The current literature ...indicates that a drastic surge in pro-oxidants, pro-apoptotic, and pro-inflammatory biomarkers in combination with diminished mitochondrial activity can potentially decrease hepatic function leading to morbidity and mortality. Consequently, there are increasing public health concerns that substantial Bisphenol-mediated effects may impact hepatocellular functions, particularly in newborns exposed to BPA and BPS postnatally. However, the acute postnatal impact of BPA and BPS and the molecular mechanisms affecting hepatocellular functions are unknown. Therefore, the current study investigated the acute postnatal effect of BPA and BPS on the biomarkers of hepatocellular functions, including oxidative stress, inflammation, apoptosis, and mitochondrial activity in male Long-Evans rats. BPA and BPS (5 and 20 microgram/Liter (μg/L) of drinking water) were administered to 21-day-old male rats for 14 days. BPS had no significant effect on apoptosis, inflammation, and mitochondrial function but significantly reduced the reactive oxygen species (51–60 %, **p < 0.01) and nitrite content (36 %, *p < 0.05), exhibiting hepatoprotective effects. As expected, based on the current scientific literature, BPA induced significant hepatoxicity, as seen by significant glutathione depletion (50 %, *p < 0.05). The in-silico analysis indicated that BPS is effectively absorbed in the gastrointestinal tract without crossing the blood-brain barrier (whereas BPA crosses the blood-brain barrier) and is not a substrate of p-Glycoprotein and Cytochrome P450 enzymes. Thus, the current in-silico and in vivo findings revealed that acute postnatal exposure to BPS had no significant hepatotoxicity.
This feature article presents many experimental results in order to explain and advance our understanding on crazing during tensile deformation of glassy polymers. Ample data are presented to show ...that crazing is an activated process and therefore takes time to emerge. For example, ductile polymers can also show crazing prior to yielding as demonstrated with bisphenol A polycarbonate and PMMA at elevated temperatures. As an integral part of the investigation, we show that crazing can emerge in absence of any ongoing deformation, i.e., taking place not during extension but after termination of the extension. More remarkably, glassy polymers such as polystyrene and amorphous poly(lactic acid) (PLA) can undergo macroscopic fracture without any ongoing extension after a rapid step extension that first results in massive crazing. Moreover, we investigate several ways to either suppress or promote craze formation. Specifically, it is shown that a craze-free ductile PLA turns brittle and develops crazing upon physical aging or the incorporation of “solvent”. Conversely, adequate pre-melt-stretching is found to prevent physical aging from causing crazing and brittle fracture. Crazing perhaps reveals the existence of structural and dynamic heterogeneity that can be more severe in one glassy polymer than another. For example, PMMA hardly shows crazing before brittle fracture at room temperature in contrast to PS. At the present, no theoretical description is available to predict which polymer is more prone to crazing since all glassy polymers of linear flexible chains show comparable characteristics in terms of the underlying chain network structure.
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•The article describes nearly all aspects of crazing in tensile drawing of glassy polymers in terms of the latest chain-level understanding of yielding and brittle fracture behavior.•Crazing as an activated process involves localized failure of chain network and has been observed in ductile polymers as well as during stress relaxation of brittle polymers.•Pre-melt stretching is an effective method to turn brittle polymers ductile and delay the onset of crazing.
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•Mn3O4 nanocatalyst showed excellent mineralization of BPA.•1O2 was the dominant reactive oxygen species in BPA degradation.•Oxygen vacancy played a vital role in generation of ...1O2.•β-scission reaction was the main transformation pathway for the degradation of BPA.•13 transformation products were decreased while 4 were increased.
In recent years, activation of persulfate via Mn-based composites has gained interest due to extraordinary kinetics and performance for the degradation of organic contaminants. However, the potential of pristine manganese oxides (Mn3O4) in removing organic compounds and its mechanism has not been comprehensively explored yet. This study systemically investigated the Mn3O4 based peroxymonsulfate (PMS) activation to effectively mitigate bisphenol A (BPA) in different real water matrixes. Substantial mineralization (75.9%) with efficient removal of BPA (96.7%) has been achieved at optimum conditions in 60 min. A long-term performance, eight cycles of reusability, has shown merely an 11% reduction in BPA removal, highlighted the higher stability of Mn3O4. The oxidizing contributions of reactive oxygen species (ROS) were in the order of 1O2 > O2•- > SO4•- >•OH. The different water matrixes have influenced BPA degradation by<10%. Linear changes in BPA aromatic contents were recorded using log-transformed ultraviolet (UV) spectra and fluorescence excitation-emission matrix (EEM). Total 17 transformation products (TPs) were detected in Mn3O4/PMS/BPA system, with 13 decreasing concentrations and 4 TPs in increasing concentration with the β-scission reaction as the main pathway for the degradation of BPA. The toxicity of BPA after degradation was also significantly suppressed measured by the activated sludge inhibition method.
An analytical method was developed for the simultaneous determination of bisphenol A (BPA), bisphenol A diglycidyl ether (BADGE) and their derivatives, BADGE·2H
2
O, BADGE·H
2
O, BADGE·HCl·H
2
O, ...BADGE·2HCl and BADGE·HCl, in canned animal food commodities using reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection. The samples were cleaned up using solid-phase extraction (SPE) with hydrophobic polystyrene–divinylbenzene (PS/DVB) copolymer sorbent. The performance characteristics confirmed that the method used was in accordance with the EU validation criteria. The recovery values ranged from 62 to 97%. The repeatability (CV
r
) and within-laboratory reproducibility (CV
W
) values ranged from 2.3 to 9.7% and from 2.8 to 10.8%, respectively, while the limit of detection (LOD) and the limit of quantification (LOQ) values ranged from 5 to 10 µg/kg and from 5 to 15 µg/kg, respectively. The method was successfully used to evaluate the levels of 7 bisphenols in 24 of the canned dog foods retailed on the Slovenian market. BADGE·2H
2
O was found in all the samples tested, with values ranging from 16 to 540 µg/kg, while BPA was found in 96% of the samples tested and ranged from <5 to 208 µg/kg. The contribution of BADGE·H
2
O and BADGE·HCl·H
2
O was minor, while no traces of BADGE, BADGE·2HCl or BADGE·HCl were detected. Epoxy phenolic coatings were identified in the cans tested by the Fourier transform infrared spectroscopy (FTIR) analysis. Given the temporary human tolerable daily intake (TDI) value of 4 µg/kg b.w./day recently laid down by the European Food Safety Authority (EFSA), these results, especially those for the BPA in canned dog foods, merit further attention and investigation.
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