Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

Potential health risks related to environmental endocrine disruptors (EEDs) have aroused research hotspots at the forefront of water treatment technologies. Herein, nitrogen-doped titanium dioxide/schwertmannite nanocomposites (N-TiO2/SCH) have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes. Due to the sustainable Fe(III)/Fe(II) conversion induced by photoelectrons, as-prepared N-TiO2/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A (BPA; ca. 100% within 60 min under visible irradiation) in a wide pH range of 3.0-7.8, which is significantly higher than that of the pristine schwertmannite (ca. 74.5%) or N-TiO2 (ca. 10.8%). In this photo-Fenton system, the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical (•OH) and singlet oxygen (1O2). Moreover, the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses. This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts, but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

Tungsten-based nanocatalysts with different structures for visible light responsive photocatalytic degradation of bisphenol A

Environmental pollution, such as water contamination, is a critical issue that must be absolutely addressed. Here, three different morphologies of tungsten-based photocatalysts (WO3 nanorods, WO3/WS2 nanobricks, WO3/WS2 nanorods) are made using a simple hydrothermal method by changing the solvents (H2O, DMF, aqueous HCl solution). The as-prepared nanocatalysts have excellent thermal stability, large porosity, and high hydrophilicity. The results show all materials have good photocatalytic activity in aqueous media, with WO3/WS2 nanorods (NRs) having the best activity in the photodegradation of bisphenol A (BPA) under visible-light irradiation. This may originate from increased migration of charge carriers and effective prevention of electron‒hole recombination in WO3/WS2 NRs, whereby this photocatalyst is able to generate more reactive •OH and •O2- species, leading to greater photocatalytic activity. About 99.6% of BPA is photodegraded within 60 min when using 1.5 g/L WO3/WS2 NRs and 5.0 mg/L BPA at pH 7.0. Additionally, the optimal conditions (pH, catalyst dosage, initial BPA concentration) for WO3/WS2 NRs are also elaborately investigated. These rod-like heterostructures are expressed as potential catalysts with excellent photostability, efficient reusability, and highly active effectivity in different types of water. In particular, the removal efficiency of BPA by WO3/WS2 NRs reduces by only 1.5% after five recycling runs and even reaches 89.1% in contaminated lake water. This study provides promising insights for the nearly complete removal of BPA from wastewater or different water resources, which is advantageous to various applications in environmental remediation.

UV and pulsed electron beam radiation for effective bisphenol A degradation

The paper presents the results of studying the efficiency of the bisphenol A transformation in water exposed to ultraviolet radiation and a high-energy-pulse-electron beam (e-beam). It has been shown that in both cases, degradation of dissolved bisphenol A occurs, accompanied by an increase in the absorption coefficient in the wavelength region of more than 300 nm. After exposure, products were recorded that fluoresced in the region of more than λ = 400 nm. The fluorescent transformation product of bisphenol A in water (λ = 425 nm) was maximum formatted after an KrCl excilamp irradiated, and under the action of an e-beam, the accumulation of this product was minimal. Under e-beam radiation (170 keV) the efficiency of bisphenol A (1 mM) removal reached 97%. The data obtained allow us to develop ideas about photolysis and radiolysis in natural water systems when knowledge about targeted and optimal conditions for the degradation of bisphenol A is needed.

Photocatalytic and electrocatalytic degradation of bisphenol A in the presence of graphene/graphene oxide-based nanocatalysts: A review

Bisphenol A (BPA), a widely recognized endocrine disrupting compound, has been discovered in drinking water sources/finished water and domestic wastewater influent/effluent. Numerous studies have shown photocatalytic and electrocatalytic oxidation to be very effective for the removal of BPA, particularly in the addition of graphene/graphene oxide (GO)-based nanocatalysts. Nevertheless, the photocatalytic and electrocatalytic degradation of BPA in aqueous solutions has not been reviewed. Therefore, this review gives a comprehensive understanding of BPA degradation during photo-/electro-catalytic activity in the presence of graphene/GO-based nanocatalysts. Herein, this review evaluated the main photo-/electro-catalytic degradation mechanisms and pathways for BPA removal under various water quality/chemistry conditions (pH, background ions, natural organic matter, promotors, and scavengers), the physicochemical characteristics of various graphene/GO-based nanocatalysts, and various operating conditions (voltage and current). Additionally, the reusability/stability of graphene/GO-based nanocatalysts, hybrid systems combined with ozone/ultrasonic/Fenton oxidation, and prospective research areas are briefly described.

Optimization of a fast and sensitive method based on matrix solid-phase dispersion-LC-ms/ms for simultaneous determination of phthalates and bisphenols in mussel samples

Bisphenols and phthalates are wide classes of endocrine disrupting chemicals (EDCs) extensively used as additives in plastic products. In this study, a fast and reliable analytical method based on matrix solid-phase dispersion (MSPD) coupled with LC-MS/MS was developed and optimized for simultaneous determination of 8 bisphenols and 7 phthalates in raw mussel extract. The LC-MS/MS method was tested for linearity (R2), inter- and intra-day repeatability, limit of detection and quantification, both for matrix-free and matrix-matched solutions. The MSPD method was optimized in terms of ratio between sample and sorbent, and the type and quantity of the eluents in order to maximize the recoveries and to minimize matrix effects. The obtained recoveries (values between 75% and 113%), limits of detection (values between 0.048 and 0.36 µg kg-1), limits of quantification (values between 0.16 and 1.28 µg kg-1), repeatability (RSD% between 1.30% and 8.41%) and linearity (R2 > 0.998) were satisfactory and suitable for the determination of target micropollutants in food samples. In addition, the low solvent consumption and fast execution make this method ideal for routinely determinations of bisphenols and phthalates in mussels.

Tuning interfacial oxygen vacancy level of bismuth oxybromide to enhance photocatalytic degradation of bisphenol A

Oxygen vacancies (OVs) have garnered significant interest for their role as active sites, enhancing the catalytic efficiency of various catalysts. Despite their widespread application in environmental purification processes, the generation of OVs conventionally depends on high-temperature conditions and strong reducing agents for the extraction of surface partial oxygen atoms from catalysts. In this work, bismuth oxybromide (BiOBr) nanosheets with varying levels of OVs were synthesized via a simple and effective solvothermal method. This novel method affords precise control over the conduction band (CB) and valence band (VB) positions of BiOBr. The presence of different OVs exhibited varying photocatalytic efficiencies in the degradation of bisphenol A (BPA) under visible light irradiation, with higher levels of OVs resulting in superior photocatalytic performance. Furthermore, radical scavenger experiments demonstrated that superoxide oxides (O2•-) and holes (h+) were the primary reactive oxygen species for BPA degradation. Additionally, BiOBr-OVs exhibited excellent anti-interference and stability in water matrices containing diverse inorganic anions and organic compounds. This work provides a simple and effective approach for the fine-regulating of catalysts through interfacial defect engineering, paving the way for their practical application in environmental decontamination.

Simulated sunlight/periodate-triggered formation of toxic halogenated bisphenols in highly saline water

Periodate (PI)-based oxidation using the activators, such as metal ions and light irradiation, has emerged as a feasible treatment strategy for the effective remediation of contaminated water and wastewater. Given the pervasive nature of PI residues and solar exposure during application, the role of solar light in remediating the challenging highly saline water matrices needs to be elucidated. In this study, bisphenol A (BPA) was selected as the targeted micropollutant, which can be efficiently eliminated by the simulated sunlight (SSL)/PI system in the presence of high-level Cl- (up to 846.0 mM) at pH 7.0. The presence of different background constituents of water, such as halides, nitrate, and dissolved organic matter, had no effect, or even accelerated BPA abatement. Particularly, the ubiquitous Br- or I- appreciably enhanced the BPA transformation efficiency, which may be ascribed to the generation of high-selective reactive HOBr or HOI. The in silico predictions suggested that the transformation products generated by halide-mediated SSL/PI systems via halogen substitutions showed greater persistence, bioaccumulation, and aquatic toxicity than BPA itself. These findings highlighted a widespread phenomenon during PI-based oxidative treatment of highly saline water, which needs special attention under solar light illumination.

Catalytic activation of persulfate by nanoscale zero-valent iron-derived supported boron-doped porous carbon for bisphenol A degradation

In this study, boron-doped porous carbon materials (BCs) with high surface areas were synthesized employing coffee grounds as carbon source and sodium bicarbonate and boric acid as precursors; afterward, nanoscale zero-valent iron (nZVI) and BCs composites (denoted as nZVI@BCs) were further prepared through reduction of FeSO4 by NaBH4 along with stirring. The performance of the nZVI@BCs for activating persulfate (PS) was evaluated for the degradation of bisphenol A (BPA). In comparison with nZVI@Cs/PS, nZVI@BCs/PS could greatly promote the degradation and mineralization of BPA via both radical and non-radical pathways. On the one hand, electron spin resonance and radical quenching studies represented that •OH, SO4•-, and O2•- were mainly produced in the nZVI@BCs/PS system for BPA degradation. On the other hand, the open circuit voltages of nZVI@BCs and nZVI@Cs in different systems indicated that non-radical pathway still existed in our system. PS could grab the unstable unpaired electron on nZVI@BCs to form a carbon material surface-confined complex ([nZVI@BCs]*) with a high redox potential, then accelerate BPA removal efficiency via direct electron transfer. Furthermore, the performances and mechanisms for BPA degradation were examined by PS activation with nZVI@BC composites at various conditions including dosages of nZVI@BCs, BPA and PS, initially pH value, temperature, common anions, and humid acid. Therefore, this study provides a novel insight for development of high-performance carbon catalysts toward environmental remediation.

Structural insight into the mechanisms and interacting features of endocrine disruptor Bisphenol A and its analogs with human estrogen-related receptor gamma

Bisphenol A (BPA) is a very important chemical from the commercial perspective. Many useful products are made from it, so its production is increasing day by day. It is widely known that Bisphenol A (BPA) and its analogs are present in the environment and that they enter our body through various routes on a daily basis as we use things made of this chemical in our daily lives. BPA has already been reported to be an endocrine disruptor. Studies have shown that BPA binds strongly to the human estrogen-related receptor gamma (ERRγ) and is an important target of it. This study seeks to understand how it interacts with ERRγ. Molecular docking of BPA and its analogs with ERRγ was performed, and estradiol was taken as a reference. Then, physico-chemical and toxicological analysis of BPA compounds was performed. Subsequently, the dynamic behavior of ERRγ and ERRγ-BPA compound complexes was studied by molecular dynamics simulations over 500 ns, and using this simulated data, their binding energies were again calculated using the MM-PBSA method. We observed that the binding affinity of BPA and its analogs was much higher than that of estradiol, and apart from being toxic, they can be easily absorbed in our body as their physicochemical properties are similar to those of oral medicines. Therefore, this study facilitates the understanding of the structure-activity relationship of ERRγ and BPA compounds and provides information about the key amino acid residues of ERRγ that interact with BPA compounds, which can be helpful to design competitive inhibitors so that we can interrupt the interaction of BPA with ERRγ. In addition, it provides information on BPA and its analogs and will also be helpful in developing new therapeutics.

Enhanced inhibition of human and rat aromatase activity by benzene ring substitutions in bisphenol A: QSAR structure-activity relationship and in silico docking analysis

Bisphenol A (BPA) is a widely used plastic material, but its potential endocrine disrupting effect has restricted its use. The BPA alternatives have raised concerns. This study aimed to compare inhibitory potencies of 11 BPA analogues on human and rat placental aromatase (CYP19A1). The inhibitory potency on human CYP19A1 ranged from bisphenol H (IC50, 0.93 μM) to tetramethyl BPA and tetrabromobisphenol S (ineffective at 100 μM) when compared to BPA (IC50, 73.48 μM). Most of them were mixed/competitive inhibitors and inhibited estradiol production in human BeWo cells. Molecular docking analysis showed all BPA analogues bind to steroid active site or in between steroid and heme of CYP19A1 and form a hydrogen bond with catalytic residue Met374. Pharmacophore analysis showed that there were 4 hydrophobic regions for BPA analogues, with bisphenol H occupying 4 regions. Bivariate correlation analysis showed that LogP (lipophilicity) and LogS (water solubility) of BPA analogues were correlated with their IC50 values. Computerized drug metabolism and pharmacokinetics analysis showed that bisphenol H, tetrabromobisphenol A, and tetrachlorobisphenol A had low solubility, which might explain their weaker inhibition on estradiol production on BeWo cells. In conclusion, BPA analogues mostly can inhibit CYP19A1 and the lipophilicity determines their inhibitory strength.

A novel pencil graphite electrode modified with an iron-based conductive metal-organic framework exhibited good ability in simultaneous sensing bisphenol A and bisphenol S

Bisphenol A (BPA) and its substitute bisphenol S (BPS) are desirable materials widely used in manufacturing plastic products but can pose carcinogenic risks to humans. A new conductive iron-based metal-organic framework (Fe-HHTP)-modified pencil graphite electrode (PGE) for electrochemically sensing BPA and BPS was prepared and fully characterized by SEM, TEM, FT-IR, XRD, and XPS. Results showed that the optimal conditions for preparing Fe-HHTP/PGE were a pH of 6.5, a Fe-HHTP concentration of 2 mg·mL-1, a deposition potential of 0 V, and a deposition time of 100 s. The Fe-HHTP/PGE prepared under such conditions harbored a significant electrocatalytic activity with a detection limit of 0.8 nM for BPA and 1.7 nM for BPS (S/N = 3). Correspondingly, the electrochemical response current was linearly correlated to BPA and BPS, ranging from 0.01 to 100 μM. Fe-HHTP/PGE also obtained satisfactory recoveries by 93.8-102.1% and 96.0-101.3% for detecting BPA and BPS in plastic food packaging samples. Our work has provided a novel electrochemical tool to simultaneously detect BPA and BPS in food packaging samples and environmental matrixes.

Surface-surface contacted direct Z-scheme TiO2-BiVO4-PI heterostructure for enhanced photoelectrocatalytic degradation of bisphenols under solar driven

Bisphenols (BPs) are a series of widely used endocrine disruptors, which potentially harm the environment and human health. In this work, a novel Z-scheme TiO2-BiVO4-PI heterostructure was synthesized, characterized, and used for the simulated sunlight-driven photoelectrocatalytic degradation of BPs. Due to the existence of surface-surface contacted direct Z-scheme between BiVO4 and PI, holes were concentrated on the valence band of BiVO4 and electrons were concentrated on the conduction band of PI, resulting in a stronger redox activity. All six BPs exhibited appreciable degradation following the order of bisphenol A (BPA, 93.5%) > bisphenol B (BPB, 92.7%) > bisphenol AP (BPAP, 85.6%) > bisphenol F (BPF, 75.9%) > bisphenol AF (BPAF, 69.8%) > bisphenol S (BPS, 39.2%), within 120 min under the optimal condition. In the process of degradation, superoxide radicals (·O2-) and hydroxyl radicals (·OH) played dominant roles, and the intermediates of BPs degradation were mainly formed via the substituent shedding or C-C bond breaking of phenol ring, hydroxylation, and ring opening of phenol ring. The ECOSAR program was used to analyze the changes in the toxicity of the intermediates, and it was proved that the toxicity showed a decrease trend during the degradation process. This study provides a Z-scheme mechanism for TiO2-BiVO4-PI, which can degrade BPs and reduce their toxicity effectively.

Hormone effects of eighteen bisphenol analogues and their effects on cellular homeostasis and the typical signal pathways

Through the transfer chain of surroundings from feed to the farmed-animals and ultimately the corresponding livestock and poultry products, people are exposed to large amounts of bisphenol analogues (BPs), such as rational emissions from manufacturing plants, feed packaging bags and food packaging contact. Some BPs have been reported to show certain toxicological effects, especially, estrogen and endocrine disrupting effect. With the increasing application of BPs, the problem is becoming more and more serious. We systematically studied the hormonal effects of 18 BPs and their effects on cell homeostasis and classical signaling pathways by using classical E-SCREEN assay, fluorescent probes and western blotting. The results confirmed the estrogen-like effect of 13 BPs and 6 BPs obtained high docking scores (Scores < -9.0) for the three receptors simultaneously with the main interactions of hydrophobic, hydrogen and π-stacking of T-type bonds. BPAP regulates cells via apoptosis and steroid signaling pathway by intracellular ROS and mitochondrial followed the caspase pathway. BPE and BPS were involved in the classical NF-κB and Hippo signaling pathways. All data provides scientific basis for the safety risk assessment of endocrine disrupting and cellular homeostasis evaluation of BPs as chronic environmental pollution.

Congener-specific uptake and accumulation of bisphenols in edible plants: Binding to prediction of bioaccumulation by attention mechanism multi-layer perceptron machine learning model

Plant accumulation of phenolic contaminants from agricultural soils can cause human health risks via the food chain. However, experimental and predictive information for plant uptake and accumulation of bisphenol congeners is lacking. In this study, the uptake, translocation, and accumulation of five bisphenols (BPs) in carrot and lettuce plants were investigated through hydroponic culture (duration of 168 h) and soil culture (duration of 42 days) systems. The results suggested a higher bioconcentration factor (BCF) of bisphenol AF (BPAF) in plants than that of the other four BPs. A positive correlation was found between the log BCF and the log Kow of BPs (R2carrot = 0.987, R2lettuce = 0.801, P < 0.05), while the log (translocation factor) exhibited a negative correlation with the log Kow (R2carrot = 0.957, R2lettuce = 0.960, P < 0.05). The results of molecular docking revealed that the lower binding energy of BPAF with glycosyltransferase, glutathione S-transferase, and cytochrome P450 (-4.34, -4.05, and -3.52 kcal/mol) would be responsible for its higher accumulation in plants. Based on the experimental data, an attention mechanism multi-layer perceptron (AM-MLP) model was developed to predict the BCF of eight untested BPs by machine learning, suggesting the relatively high BCF of bisphenol BP, bisphenol PH, and bisphenol TMC (BCFcarrot = 1.37, 1.50, 1.03; BCFlettuce = 1.02, 0.98, 0.67). The prediction of BCF for ever-increasing varieties of BPs by machine learning would reduce repetitive experimental tests and save resources, providing scientific guidance for the production and application of BPs from the perspective of priority pollutants.

Bisphenols and perfluoroalkyls alter human stem cells integrity: A possible link with infertility

Bisphenols and Perfluoroalkyls are chemical compounds widely used in industry known to be endocrine disruptors (EDs). Once ingested through contaminated aliments, they mimic the activity of endogenous hormones leading to a broad spectrum of diseases. Due to the extensive use of plastic in human life, particular attention should be paid to antenatal exposure to Bisphenols and Perfluoroalkyls since they cross the placental barrier and accumulates in developing embryo. Here we investigated the effects of Bisphenol-A (BPA), Bisphenol-S (BPS), perfluorooctane-sulfonate (PFOS) and perfluorooctanoic-acid (PFOA), alone or combined, on human-induced pluripotent stem cells (hiPSCs) that share several biological features with the stem cells of blastocysts. Our data show that these EDs affect hiPSC inducing a great mitotoxicity and dramatic changes in genes involved in the maintenance of pluripotency, germline specification, and epigenetic regulation. We also evidenced that these chemicals, when combined, may have additive, synergistic but also negative effects. All these data suggest that antenatal exposure to these EDs may affect the integrity of stem cells in the developing embryos, interfering with critical stages of early human development that might be determinant for fertility. The observation that the effects of exposure to a combination of these chemicals are not easily foreseeable further highlights the need for wider awareness of the complexity of the EDs effects on human health and of the social and economic burden attributable to these compounds.

Melatonin and Vitamins as Protectors against the Reproductive Toxicity of Bisphenols: Which Is the Most Effective? A Systematic Review and Meta-Analysis

Bisphenols such as bisphenol A (BPA), S (BPS), C (BPC), F (BPF), AF (BPAF), tetrabromobisphenol, nonylphenol, and octylphenol are plasticizers used worldwide to manufacture daily-use articles. Exposure to these compounds is related to many pathologies of public health importance, such as infertility. Using a protector compound against the reproductive toxicological effects of bisphenols is of scientific interest. Melatonin and vitamins have been tested, but the results are not conclusive. To this end, this systematic review and meta-analysis compared the response of reproductive variables to melatonin and vitamin administration as protectors against damage caused by bisphenols. We search for controlled studies of male rats exposed to bisphenols to induce alterations in reproduction, with at least one intervention group receiving melatonin or vitamins (B, C, or E). Also, molecular docking simulations were performed between the androgen (AR) and estrogen receptors (ER), melatonin, and vitamins. About 1234 records were initially found; finally, 13 studies were qualified for review and meta-analysis. Melatonin plus bisphenol improves sperm concentration and viability of sperm and increases testosterone serum levels compared with control groups; however, groups receiving vitamins plus bisphenols had lower sperm concentration, total testis weight, and testosterone serum levels than the control. In the docking analysis, vitamin E had the highest negative MolDock score, representing the best binding affinity with AR and ER, compared with other vitamins and melatonin in the docking. Our findings suggest that vitamins could act as an endocrine disruptor, and melatonin is most effective in protecting against the toxic effects of bisphenols.

Effective immobilization of bisphenol A utilizing activated biochar incorporated into soil: combined with batch adsorption and fixed-bed column studies

This study presented the mixture of biochar and soil for removal of bisphenol A (BPA) to assess environmental remediation ability. Using phoenix tree leaves as biomass and phosphoric acid as activator, after one-step hydrothermal and short-term activation, the eventual solid product was phosphoric acid hydrothermal activated carbon (HPC). The characterizations showed that HPC had the high specific surface (994.21 m2·g-1), and large unsaturated esters and hydroxyl groups. The saturated adsorption capacities of batch and column adsorption for the addition of 0.5% HPC to soil were 0.790 mg·g-1 and 67.23 mg·kg-1, while to the natural soil were 0.236 mg·g-1 and 8.75 mg·kg-1, respectively. The adsorption kinetics and thermodynamic analysis indicated that the adsorption process utilizing HPC incorporated into soil was a chemical reaction rate-controlled, physical-dominated multilayer adsorption, and spontaneous endothermic. Also, batch adsorption experiments and analysis were performed under different pH levels, HPC contents, organic acid concentrations, and cationic strengths. Successively, fixed-bed column experiments were carried out with and without the HPC; the results showed that the wide mass transfer zone led to the effective fixation of BPA, and the organic acid had no obvious effect on the fixation of BPA when the 1.0% HPC mixed with soil. Finally, through characterizations and data analysis, the enhanced adsorption of BPA by HPC mixed with soil mainly relied on π-π interaction, hydrogen bonding, followed by electrostatic attraction and pore filling.

Twelve natural estrogens and ten bisphenol analogues in eight drinking water treatment plants: Analytical method, their occurrence and risk evaluation

Bisphenol analogues (BPs) and natural estrogens (NEs) as two important groups of endocrine-disrupting compounds (EDCs) in drinking water treatment plants (DWTPs) have been hardly investigated except bisphenol A (BPA) and three major NEs including estrone (E1), 17β-estradiol (E2) and estriol (E3). In this study, a GC-MS analytical method was firstly established and validated for trace simultaneous determination of ten BPs and twelve NEs in drinking water, which included BPA, bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bsiphenol F (BPF), bsiphenol P (BPP), bisphenol S (BPS), bisphenol Z (BPZ), bisphenol AF (BPAF), bisphenol AP (BPAP), E1, E2, E3, 17α-estradiol (17α-E2), 2-hydroestrone (2OHE1), 16hydroxyestrone (16α-OHE1), 4-hydroestrone (4OHE1), 2-hydroxyesstradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 17-epiestriol (17epiE3), 16-epiestriol (16epiE3) and 16keto-estraiol (16ketoE2). This investigation showed that eighteen out of twenty-two targeted compounds were detected in drinking source waters of eight DWTPs with concentrations ranging from not detected to 142.8 ng/L. Although the conventional treatment process of DWTP could efficiently remove both BPs and NEs with respective removal efficiencies of 74.1%-90.9% and 74.5%-100%, BPA, BPS, BPE, BPZ, E1, 2OHE1, and 2OHE2 were found in the finished drinking waters. Chlorination could remove part of BPs and NEs, but the efficiency varied greatly with DWTP and the reason was unknown. In the finished drinking waters of eight DWTPs, the highest chemically calculated estrogen equivalence (EEQ) derived from BPs and NEs was up to 6.11 ngE2/L, which was over 22 times that could do harm to zebrafish, indicating a potential risk to human health. Given the fact that many chlorination products of BPs and NEs likely have higher estrogenic activities, the estrogenic effect of BPs and NEs in finished drinking water should be accurately examined urgently with the inclusion of BPs, NEs as well as their main chlorinated by-products. This study shed new light on the occurrence, removal, and potential estrogenic effects of BPs and NEs in DWTPs.

Comparison of effects of multiple oxidants with an ultrasonic system under unified system conditions for bisphenol A degradation

Bisphenol A (BPA) as a trace contaminant has been reported, due to widespread use in the plastics industry. This study applied the 35 kHz ultrasound (US) to activate four different common oxidants (H₂O₂, HSO₅^-, S₂O₈^2-, and IO₄^-) for BPA degradation. With increasing initial concentration of oxidants, the degradation rate of BPA increased. The synergy index confirmed that a synergistic relationship between US and oxidants. This study also examined the impact of pH and temperature. The results showed that the kinetic constants of US, US-H₂O₂, US-HSO₅^- and US-IO₄^-decreased when the pH increased from 6 to 11. The optimal pH for US-S₂O₈^2- was 8. Notably, increasing temperature decreased the performance of US, US-H₂O₂, and US-IO₄^- systems, while it could increase the degradation of BPA in US-S₂O₈^2- and US-HSO₅^-. The activation energy for BPA decomposition using the US-IO₄^- system was the lowest, at 0.453nullkJnullmol^-1, and the synergy index was the highest at 2.22. Additionally, the ΔG# value was found to be 2.11 + 0.29T when the temperature ranged from 25 °C to 45 °C. The main oxidation contribution is achieved by hydroxyl radicals in scavenger test. The mechanism of activation of US-oxidant is heat and electron transfer. In the case of the US-IO₄^- system, the economic analysis yielded 271 kwh m^-3, which was approximately 2.4 times lower than that of the US process.

Mn(III)-mediated bisphenol a degradation: Mechanisms and products

Bisphenol A (BPA) is a high production volume chemical with potential estrogenic effects susceptible to abiotic degradation by MnO₂. BPA transformation products and reaction mechanisms with MnO₂ have been investigated, but detailed process understanding of Mn(III)-mediated degradation has not been attained. Rapid consumption of BPA occurred in batch reaction vessels with 1 mM Mn(III) and 63.9 ± 0.7% of 1.76 ± 0.02 μmol BPA was degraded in 1 hour at circumneutral pH. BPA was consumed at 1.86 ± 0.09-fold higher rates in vessels with synthetic MnO₂ comprising approximately 13 mol% surface-associated Mn(III) versus surface-Mn(III)-free MnO₂, and 10-35% of BPA transformation could be attributed to Mn(III) during the initial 10-min reaction phase. High-resolution tandem mass spectrometry (HRMS/MS) analysis detected eight transformation intermediates in reactions with Mn(III), and quantum calculations proposed 14 BPA degradation products, nine of which had not been observed during MnO₂-mediated BPA degradation, suggesting mechanistic differences between Mn(III)- versus MnO₂-mediated BPA degradation. The findings demonstrate that both Mn(III) and Mn(IV) can effectively degrade BPA and indicate that surface-associated Mn(III) increases the reactivity of synthetic MnO₂, offering opportunities for engineering more reactive oxidized Mn species for BPA removal.

Optimized fabrication of Cu-doped ZnO/calcined CoFe‒LDH composite for efficient degradation of bisphenol a through synergistic visible-light photocatalysis and persulfate activation: Performance and mechanisms

A novel magnetically separable Cu/ZnO/CoFe‒CLDH composite, whose synthesis was optimized using the Taguchi approach, was optimally synthesized by hydrothermally coupling Cu-doped ZnO and calcined CoFe-LDH. The synthesized Cu/ZnO/CoFe‒CLDH was applied to construct a synergistic process of integrating visible-light photocatalysis (VPC) with persulfate activation (PSA) and to degrade bisphenol A (BPA). Various characterizations proved that Cu/ZnO/CoFe‒CLDH possessed excellent physicochemical, optoelectronic and magnetic properties, thereby enhancing the catalytic performance. The Cu/ZnO/CoFe‒CLDH composite achieved highly efficient BPA degradation during the synergistic VPC‒PSA process, and its reaction rate constant (0.74 h^-1) was 6.17-, 4.11-, and 2.85-fold higher than that of Cu/ZnO, CoFe‒CLDH, and Cu/ZnO/CoFe‒CLDH (VPC only), respectively. Moreover, the effects of the catalyst dosage, initial pollutant concentration, solution pH, persulfate dosage and coexisting ions on BPA degradation were comprehensively investigated. Radical-trapping experiments revealed that the contributions of ·OH, SO₄·^‒, ·O₂^-, and ¹O₂ involved in BPA degradation. Based on the intermediates identified by LC/MS, the main BPA degradation pathways were determined, the overall trend of which reflects a decreasing ecotoxicity. This study verified the effectiveness of the synergistic VPC‒PSA process with Cu/ZnO/CoFe‒CLDH, which could be used as a new reference for removing organic micropollutants from water.

Risk assessment of bisphenol related compounds in canned convenience foods, olives, olive oil, and canned soft drinks in Turkey

The presence of Bisphenol A (BPA), Bisphenol A Diglycidyl Ether (BADGE), and their derivatives in seventy-nine samples of food products available in Turkish stores was determined using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Among Bisphenol A and its analogues, BPA was the most detected migrant with 56.97%. Fish products had the highest level of BPA with 0.102 mg/kg although only three fish samples exceeded the Specific Migration Limit (SML) for BPA of 0.05 mg/kg of food. The BPF, BPS, and BPB in all analyzed foods ranged between 0-0.021, 0-0.036, and 0.072 mg/kg, respectively. BADGE derivates, BADGE·2H₂O and cyclo-di-BADGE (CdB) were present in 57 and 52 samples with concentrations ranging between 0-0.354, and 0-1.056 mg/kg, respectively. All the analyzed traditional Turkish ready-to-eat meals and fish products were contaminated with BADGE·2H₂O and CdB. The overall levels of BADGE and the derivates were below the specific migration limit. CdB was found at higher concentrations in traditional Turkish ready-to-eat meals, up to 1.056 mg/kg. The CdB concentration in most of the samples was above the highest figure with 0.05 mg/kg authorized by the German Federal Institute for Risk Assessment. The predominant chlorinated derivative was BADGE·H₂O·HCl which was found in thirty-seven samples in the range of 0.007-0.061 mg/kg.

Early-life bisphenol AP exposure impacted neurobehaviors in adulthood through microglial activation in mice

Bisphenol AP (BPAP), a structural analog of bisphenol A (BPA), has been widely detected in environment and biota. BPAP was reported to interfere with hormone and metabolism, while limited data were available about its effects on neurobehavior, especially exposure to it during early-life time. A mouse model of early-life BPAP exposure was established to evaluate the long-term neurobehaviors in offspring. Collectively, early-life BPAP exposure caused anxiety-like behaviors and impaired learning and memory in adult offspring. Through brain bulk RNA-sequencing (RNA-seq), we found differential expressed genes were enriched in pathways related to behaviors and neurodevelopment, which were consistent with the observed phenotype. Besides, single-nucleus RNA-sequencing (snRNA-seq) showed BPAP exposure altered the transcriptome of microglia in hippocampus. Mechanistically, BPAP exposure induced inflammations in hippocampus through upregulating Iba-1 and activating the microglia. In addition, we observed that BPAP exposure could activate peripheral immunity and promote proportion of macrophages and activation of dendritic cells in the offspring. In conclusion, early-life exposure to BPAP impaired neurobehaviors in adult offspring accompanied with excessive activation of hippocampal microglia. Our findings provide new clues to the underlying mechanisms of BPAP's neurotoxic effects and therefore more cautions should be taken about BPAP.

Removal of bisphenol A and methylene blue through persulfate activation by calcinated α-MnO2 nanorods: effect of ultrasonic assistance and toxicity assessment

This work investigates the efficacy of α-MnO₂ nanorods for persulfate-mediated degradation of bisphenol A (BPA) and methylene blue (MB), in silent and ultrasonic-assisted systems. The conversion of α-MnO₂ nanoparticle flakes to nanorods occurs upon calcination at a temperature of 400 °C for 3 h under the ramping conditions. The comparative characterization of nanomaterials pre- and post-calcination reveals better physical, chemical, and thermal properties of α-MnO₂ nanorods. The impact of various operational parameters such as pH, dosage of nanorods, persulfate dose, selected contaminant concentration, ultrasound frequency and power, scavengers, and landfill leachate medium on the degradation of pollutants is also assessed. The ultrasonic assistance yields higher removal for both BPA and MB than the silent system. This may be attributed to the generation of more radicals as ultrasound activates persulfate. This can be due to acoustic cavitation, which leads to better solute dissociation and excited state. The results obtained through scavenger tests reveal that both OH^• and SO₄^•- can contribute to degradation, but the role of SO₄^•- is found dominant. Significant removal of BPA and MB ((BPA)_silent, 87.12%; (MB)_silent, 96.54%; (BPA)_ultrasonic, 88.75%; (MB)_ultrasonic, 93.86%)) is observed in landfill leachate medium. The degradation pathway for pollutants is also proposed. The toxicity of pollutants and their degradation intermediates are evaluated using Ecological Structure Activity Relationships (ECOSAR) program. The results indicate reduced toxicity of BPA intermediates, while most MB degradation intermediates show higher toxicity. Therefore, it can be affirmed that removing pollutants does not ensure a completely non-toxic process. However, the study proposes a comprehensive toxicity evaluation and eliminating toxic intermediates for completely harmless wastewater treatment.

Bisphenol A and its substitutes in the aquatic environment: Occurrence and toxicity assessment

Bisphenol A is classified as a high production volume chemical commonly used in the manufacture of polycarbonate plastics, epoxy resins and thermal paper. The endocrine disrupting properties of this xenobiotic have led to the restriction and prohibition of its use in many consumer products. To date, many chemical compounds with a chemical structure similar to bisphenol A have been used in consumer products as its replacement. The ubiquitous occurrence of bisphenol A and its substitutes in the environment and their endocrine activity as well as adverse effects on aquatic organisms is a global concern, especially because many available literature reports show that many substitutes (e.g. bisphenol AF, bisphenol AP, bisphenol B, bisphenol C, bisphenol F, bisphenol G, bisphenol FL, tetrabromobisphenol A) exert adverse effects on aquatic organisms, similar to, or even stronger than bisphenol A. Therefore, the objective of this paper is to provide a comprehensive overview of the production, sources, occurrence and associated toxicity, as well as the endocrine activity of bisphenol A and its substitutes on aquatic species. The environmental levels and ecotoxicological data presented in this review allowed for a preliminary assessment and prediction of the risk of bisphenol A and its substitutes for aquatic organisms. Furthermore, the data collected in this paper highlight that several compounds applied in bisphenol A-free products are not safe alternatives and regulations regarding their use should be introduced.

System-wide health risk prediction for 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene(MBP), a major active metabolite of environmental pollutant and food contaminant - Bisphenol A

Human exposure to plastic contaminated foods and environmental micro/nano plastic derived chemicals necessitates system-wide health risk assessment. Hence, current study intend to explore the mode of action (MoA) based adverse outcome pathways of 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), the major active metabolite of bisphenol A (BPA). The computational study employed broad range of target prediction, systems biology tools and molecular docking protocols. Further, validation of MBP targets was done using protein-ligand fluorescence quenching assay, endothelial cell culture and chicken embryo vascular angiogenesis models. Interestingly, the current results illustrate that various physiological signaling pathways (MAPK and VEGF related angiogenesis signaling) and disease progression pathways (hypertension, cancer and endocrine disorders) were enriched as potential targets of MBP. Further, docking studies highlights the possible binding mechanism of MBP with important targets including endothelial nitric oxide synthase (eNOS) and serum albumin (BSA). In addition, the validation studies on MBP-BSA interaction (fluorescence quenching), eNOS derived nitric oxide (NOx) generation in endothelial cells and chicken embryo angiogenesis support the system-wide impacts of MBP with highlights on cardiovascular pathogenesis. Thus, the current observation provides novel insights into the system wide impacts of MBP for the futuristic health risk assessment of plastic derived chemicals.

Potential toxicity of bisphenol A to α-chymotrypsin and the corresponding mechanisms of their binding

Bisphenol A (BPA) is an endocrine disruptor widely existing in plastics and resins, which can accumulate in animals and human bodies, posing a potential threat to the physiological and biochemical reactions of human beings or other organisms. α-Chymotrypsin is a kind of proteolytic enzyme existing in humans and animals, which can cause diseases when its activity is excessive. However, there is a lack of research on the mechanism of endocrine disruptors affecting α-chymotrypsin activity. In this study, the interaction between BPA and α-chymotrypsin was proved via multiple spectroscopic approaches, enzyme activity change, isothermal titration calorimetry and molecular docking. Results showed that α-chymotrypsin's polypeptide chains were unfolded, and protein skeletons were loosened with the exposure to BPA. α-Helix content increased and β-sheet content was decreased. The particle size of the BPA-α-chymotrypsin complex became smaller. Fluorescence sensitization may also be explained by a perturbation of the chromophore Trp 141. The thermodynamic parameters of the binding reaction were measured by isothermal titration calorimetry (ITC), which showed that there was hydrophobic interaction between BPA and α-chymotrypsin, which was consistent with the results of molecular docking. Moreover, BPA may stop near the active center of α-chymotrypsin and interact with the key residues His 57 and Ser 195. The above phenomenon explained the result that the activity of α-chymotrypsin increased to 139% when exposed to high dose BPA (40 μM). Taken together, the effects of BPA on the structure and function of α-chymotrypsin were clarified at the molecular level, which made up the gap in the mechanism of BPA on the proteolytic enzyme, and provided a reliable basis for disease avoidance and prevention.

Bisphenol A removal in treated wastewater matrix at neutral pH using magnetic graphite intercalation compounds as persulfate activators

Effluents of municipal wastewater treatment plants (WWTPs) are major sources for releasing contaminants of emerging concern (CECs) into the aquatic environment, which can result in negative effects on aquatic ecosystems and, as a consequence, on humans. Herein, the graphite intercalation concept was used to synthesize heterogeneous catalysts to degrade bisphenol A (BPA) as a model CEC in municipal WWTP effluents at neutral pH. The catalyst was synthesized using the simple molten salt method and showed several benefits, such as iron leaching prevention and stability in environmental matrices. Different methods were applied to describe the catalyst's structural characteristics. The proposed system removed 99.3% of BPA in 75 min using 2 g/L of the synthesized catalyst and 1.19 g/L (5 mM) persulfate at neutral pH. Quenching experiments showed that catalytic activities and BPA removals were significantly aided by both radical and non-radical pathways through the generation of free radicals and singlet oxygen (¹ O₂ ). Furthermore, the reuse of recycled synthesized catalyst was investigated on treated urban wastewater, and the results showed that the catalyst could degrade BPA from the wastewater in consecutive cycles, demonstrating its applicability under real conditions. PRACTITIONER POINTS: BPA was effectively removed from the effluents of municipal WWTPs at neutral pH. A new catalyst (magnetic GIC) was fabricated for heterogeneous catalytic systems. The catalyst activates persulfate to generate free radicals and ¹ O₂ , indicating that radical and non-radical pathways contribute to BPA degradation. The catalyst showed the ability to remove BPA even in the sixth cycle of use, demonstrating its stability and reusability.

The Association between the Bisphenols Residues in Amniotic Fluid and Fetal Abnormalities in Polish Pregnant Women-Its Potential Clinical Application

The present study aimed to investigate the relationship between the concentrations of bisphenols residues in the amniotic fluid (AF) samples collected during amniocentesis and fetal chromosomal abnormalities in pregnant women. A total of 33 pregnant Polish women aged between 24 and 44 years, and screened to detect high risk for chromosomal defects in the first trimester, were included in this study. Samples were collected from these patients during routine diagnostic and treatment procedures at mid-gestation. The concentrations of various bisphenols residues in the samples were determined by liquid chromatography coupled with triple quadrupole tandem mass spectrometry (LC-ESI-QqQ-MS/MS). Residues of eight analytes (BPS, BPF, BPA, BPAF, BADGE, BADGE•2H₂O, BADGE•H₂O•HCl and BADGE•2HCl) were detected in amniotic fluid samples in the range 0.69 ng/mL to 3.38 ng/mL. Fetuses with chromosomal abnormalities showed a slightly higher frequency of occurrence of selected bisphenols residues in the AF samples collected between 15-26 weeks of pregnancies. Finally, the proposed method was applied in the simultaneous determination of several endocrine-disrupting chemicals from bisphenol group in 33 human AF samples. BADGE•H2O•HCl has been identified in the AF samples taken from women older than average in the examined group. The number of detected compounds has been significant for the following analytes: BPS, BPAF, BADGE•H₂O•HCl and BADGE. The proposed method may be an attractive alternative for application in large-scale human biomonitoring studies.

Adverse (geno)toxic effects of bisphenol A and its analogues in hepatic 3D cell model

Bisphenol A (BPA) is one of the most widely used and versatile chemical compounds in polymer additives and epoxy resins for manufacturing a range of products for human applications. It is known as endocrine disruptor, however, there is growing evidence that it is genotoxic. Because of its adverse effects, the European Union has restricted its use to protect human health and the environment. As a result, the industry has begun developing BPA analogues, but there are not yet sufficient toxicity data to claim that they are safe. We investigated the adverse toxic effects of BPA and its analogues (BPS, BPAP, BPAF, BPFL, and BPC) with emphasis on their cytotoxic and genotoxic activities after short (24-h) and prolonged (96-h) exposure in in vitro hepatic three-dimensional cell model developed from HepG2 cells. The results showed that BPFL and BPC (formed by an additional ring system) were the most cytotoxic analogues that affected cell viability, spheroid surface area and morphology, cell proliferation, and apoptotic cell death. BPA, BPAP, and BPAF induced DNA double-strand break formation (γH2AX assay), whereas BPAF and BPC increased the percentage of p-H3-positive cells, indicating their aneugenic activity. All BPs induced DNA single-strand break formation (comet assay), with BPAP (≥0.1 μM) being the most effective and BPA and BPC the least effective (≥1 μM) under conditions applied. The results indicate that not all of the analogues studied are safer alternatives to BPA and thus more in-depth research is urgently needed to adequately evaluate the risks of BPA analogues and assess their safety for humans.

Human dietary exposure to bisphenol-diglycidyl ethers in China: Comprehensive assessment through a total diet study

Despite the widespread use of bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) in various consumer products as protective plasticizer, studies on human dietary exposure to these compounds are scare. In this study, nine bisphenol diglycidyl ethers (BDGEs) including BADGE, BFDGE, and seven of their derivatives were determined in the Chinese adult population based on composite dietary samples collected from the sixth (2016-2019) China total diet study (TDS). Contamination level of nine BDGEs was determined in 288 composite dietary samples from 24 provinces in China. BADGE·2H₂O and BADGE are the most frequently detected and BADGE·2H₂O presented the highest mean concentration (2.402 μg/kg). The most contaminated food composite is meats, with a mean ∑₉BDGEs of 8.203 μg/kg, followed by aquatic products (4.255 μg/kg), eggs (4.045 μg/kg), and dairy products (3.256 μg/kg). The estimated daily intake (EDI) of ∑₉BDGEs based on the mean and 95th percentile concentrations are 121.27 ng/kg bw/day and 249.71 ng/kg bw/day. Meats, eggs, and aquatic products are the main source of dietary exposure. Notably, beverages and water, alcohols were the main contributors of dietary exposure to BADGE and BADGE·2H₂O, followed by animal-derived foods. Dietary exposure assessment demonstrated that human dietary BDGEs do not pose risks to general population based on the mean and 95th percentile hazard index with < 1. This is the first comprehensive national dietary exposure assessment of BDGEs in Chinese general population.

Hydrogen sulfite promoted the activation of persulfate by μM Fe2+ for bisphenol A degradation

This study evaluated the improvement of bisphenol A (BPA) elimination through hydrogen sulfite (HS) coupling with persulfate (PS) activated by low amounts of Fe²⁺. Under the optimum condition (10 μM Fe²⁺, 0.6 mM HS, 0.8 mM PS, pH = 4.0), 100% BPA (5 μM) was removed within 15 min. Sulfate radical (SO₄^•-) and singlet oxygen (¹O₂) were confirmed as the primary active species for BPA degradation in the Fe²⁺/HS/PS system, and the steady-state concentration of SO₄^•- and ¹O₂ was 2.43 × 10^-9 M and 1.67 × 10^-9 M, respectively. Besides, FeHSO₃⁺ and FeOHSO₃H⁺ were the main iron species in the Fe²⁺/HS/PS system. The removal potency of BPA depended on the operation parameters, such as chemical reagent dosages, reaction temperature, and the solution initial pH. The impact of NO₃^-, SO₄^2-, and humic acid (HA) on BPA removal was negligible, whereas Cl^-, HCO₃^-, and HPO₄^2- restrained BPA decomposition. Two injections of HS could improve the limitation of BPA degradation efficiency due to the rapid consumption of HS in the reaction process. The lower removal efficiency of BPA was observed in real water matrices than that in ultrapure water. Whatever, up to 58.1%, 66.3%, 68.1%, and 88.1% of BPA were removed from domestic wastewater, lake water, river water, and tap water within 10 min, respectively. In addition, the BPA degradation process was characterized by the 3D fluorescence spectra technique, which indicated the BPA oxidation intermediates also have fluorescence characteristics. Moreover, 6 intermediate products were identified, and the possible degradation pathways of BPA were proposed. Additionally, the Fe²⁺/HS/PS system also exerted an excellent performance for the removal of other representative organic contaminants including enrofloxacin, acid orange 7, acetaminophen, and phenol. All results indicated that the Fe²⁺/HS/PS system could be a promising method for organic pollutant removal.

Immobilized BiOCl0.75I0.25/g-C3N4 nanocomposites for photocatalytic degradation of bisphenol A in the presence of effluent organic matter

The BiOCl_0.75I_0.25/g-C₃N₄ nanosheet (BCI-CN) was successfully immobilized on polyolefin polyester fiber (PPF) through the hydrothermal method. The novel immobilized BiOCl_0.75I_0.25/g-C₃N₄ nanocomposites (BCI-CN-PPF) were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy EDS, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) to confirm that BCI-CN was successfully immobilized on PPF with abundant oxygen vacancies reserved. Under simulated solar light irradiation, 100 % of bisphenol A (BPA) with an initial concentration of 10 mg·L^-1 was degraded by BCI-CN-PPF (0.2 g·L^-1 of BCI-CN immobilized) after 60 min. A similar photocatalytic efficiency of BPA was obtained in the presence of effluent organic matter (EfOM). The photocatalytic degradation of BPA was not affected by EfOM <5 mg-C/L. In comparison, the photocatalytic performance was considerably inhibited by EfOM with a concentration of 10 mg-C/L. Furthermore, photogenerated holes and superoxide radicals predominated in the photocatalytic degradation processes of BPA. The total organic carbon (TOC) removal efficiencies of BPA and EfOM were 75.2 % and 50 % in the BCI-CN-PPF catalytic system. The BPA removal efficiency of 94.9 % was still achieved in the eighth cycle of repeated use. This study provides a promising immobilized nanocomposite with high photocatalytic activity and excellent recyclability and reusability for practical application in wastewater treatment.

Mn2O3/Mn3O4-Cu1.5Mn1.5O4 spinel as an efficient Fenton-like catalyst activating persulfate for the degradation of bisphenol A: Superoxide radicals dominate the reaction

In this work, a Mn₂O₃/Mn₃O₄-Cu_1.5Mn_1.5O₄ spinel was fabricated and utilised as a catalyst to activate peroxydisulfate (PDS) leading to degradation of bisphenol A (BPA). The results showed that the system exhibited an excellent turnover frequency (TOF) of 2.7 × 10^-3 s^-1 and high stability. The amount of ion leaching was small and the degree of mineralisation was up to 66.2%. Superoxide radicals (O₂^-) were determined to be the dominant active species in the system. ≡Mn(II) and oxygen vacancies (V_o) were found to be the main active sites at the catalyst surface. The activation of PDS by the spinel catalyst and the reduction of dissolved oxygen both contributed to the production of O₂^- species. The synergistic effect of ≡Cu(I)/≡Cu(II) and ≡Mn(II)/≡Mn(III) redox pairs enabled the reaction to occur continuously. These results suggest the promise of this novel spinel catalyst in the removal of refractory organic compounds due to its excellent performance and stability. The catalyst may thus have great utility for environmental remediation.

Rapid and reagent-free bioassay using autobioluminescent yeasts to detect agonistic and antagonistic activities of bisphenols against rat androgen receptor and progesterone receptor

Bisphenol A (BPA) and its analogues have been classified as endocrine disruptors via binding to nuclear receptors. Two novel bioassays, BLYrARS and BLYrPRS, were developed for rapid detection of agonistic and antagonistic activities of BPA and five of its analogues binding rat androgen receptor (rAR) and rat progesterone receptor (rPR). The reporter bioassay was based on two autonomously bioluminescent strains of the yeast Saccharomyces cerevisiae, recombined with a bacterial luciferase reporter gene cassette (lux) that can produce autofluorescence, regulated by the corresponding hormone response element acting as the responsive promoter. The bioluminescent signal is autonomous and continuous without cell lysis or addition of exogenous reagents. The AR agonist R1881 could be detected at 4 h with a half-maximal effective concentration (EC₅₀) of ~9.4 nM. The PR agonist progesterone could be determined at 4 h with an EC₅₀ of ~2.74 nM. None of the sixteen bisphenols presented agonistic activities against rAR and rPR. However, thirteen BPs were rAR antagonists and eleven BPs acted as rPR antagonists with different potency. The BLYrARS and BLYrPRS bioassay characterized by automated signal acquisition without additional manipulations or cost can be applied for simple and rapid detection of agonistic and antagonistic activities of BPs and other compounds acting as agonists or antagonists of rAR and rPR. Based on data derived by use of this bioassay endocrine-disrupting activities of some BPA analogues are more potent than BPA.

New insights into humic acid-boosted conversion of bisphenol A by laccase-activated co-polyreaction: Kinetics, products, and phytotoxicity

How humic acid (HA) modifies bisphenol A (BPA) conversion in exoenzyme-activated polyreaction is poorly understood. Herein, the influencing mechanism of HA on laccase-induced BPA self-polymerization was investigated, and the phytotoxicity of the produced BPA self/co-polymers was assessed for the first time. HA prominently boosted BPA elimination, and the rate constants of BPA conversion augmented from 0.61 to 1.43 h^-1 as HA level raised from 0 to 50 mg·L^-1. It is because the generated BPA-HA co-polymers promptly lowered the yields of long-chain BPA self-oligomers, consequently maintaining laccase activity through opening enzymatic substrate-binding pockets. Notably, a few BPA monomers were re-released from the loosely bound self-polymers and co-polymers, and the releasing amounts respectively were 13.9 - 22.4% and 0.3 - 0.5% at pH 2 - 11. Formation of self/co-polymers was greatly conducive to avoiding BPA biotoxicity. Compared with BPA self-polymers, the phytotoxicity of BPA co-polymers to germinated radish (Raphanus sativus L.) seeds was lower due to these covalently bound products were more complex and stable. It follows that laccase-mediated co-polymerization played a significant role in BPA conversion, contaminant detoxification, and carbon sequestration. These findings are not only beneficial to clarifying exoenzyme-activated the generation mechanism of BPA co-polymers in water, but to reusing these supramolecular aggregates in crop growth.

Association of serum bisphenol AF concentration with depressive symptoms in adolescents: A nested case-control study in China

BACKGROUND

As an important alternative to bisphenol A (BPA), bisphenol AF (BPAF) is widely used and can be detected in multiple human biological samples. However, there are few studies on neurotoxicity of BPAF at present. In particular, no epidemiological studies have investigated BPAF in relation to depressive symptoms in adolescents. Here, our study aimed to evaluate the associations between serum BPAF concentrations and depressive symptoms in adolescents.

METHODS

A nested case-control study within an ongoing longitudinal prospective adolescent cohort that was established in Huaibei, China was conducted. A total of 175 participants who had new-onset depressive symptoms (cases) and 175 participants without depressive symptoms (controls) were included. Serum BPAF concentrations was measured using ultra-high-performance liquid chromatography-tandem mass spectrometry. The associations between BPAF exposure and the risk of depressive symptoms in adolescents were assessed using conditional logistic regression. The dose-response relationship between BPAF level and depressive symptoms was estimated using restricted cubic spline analyses.

RESULTS

In this study, the detection rate of serum BPAF was 100%, and the median (interquartile range, IQR) serum BPAF concentration was 5.24 (4.41-6.11) pg/mL in the case group and 4.86 (4.02-5.77) pg/mL in the control group (P = 0.009). Serum BPAF exposure was a risk factor for depressive symptoms (odds ratio (OR)= 1.132, 95% confidence interval (CI):1.013-1.264). After adjustment for all for confounders, compared with the low-exposure group, the high-exposure group had a 2.806-fold increased risk of depressive symptoms (OR=2.806, 95% CI: 1.188-6.626). Stratified analysis by sex revealed that males were more vulnerable to BPAF exposure than females. After adjustment for all confounders, compared with the low-exposure group, the relative risk of depressive symptoms in the high-exposure group was 3.858 (95% CI: 1.118-12.535) for males, however, no significant association between BPAF exposure and depressive symptoms was found in females. In addition, there was a marked linear association between BPAF exposure and the risk of depressive symptoms in the total population and in males.

CONCLUSIONS

The adolescents in this study were widely exposed to low levels of BPAF. A significant positive association was found between serum BPAF levels and the risk of depressive symptoms. The association was significantly modified by sex, and males were more vulnerable to BPAF exposure than females.

Removal effects and potential mechanisms of bisphenol A and 17α-ethynylestradiol by Biogenic Mn oxides generated by Bacillus sp. WH4

Endocrine disrupting compounds (EDCs), such as bisphenol A (BPA) and 17α-ethynylestradiol (EE2), have increasingly negative effects on human and wildlife health. In this study, the biogenic Mn oxides (BMOs) generated by Bacillus sp. WH4 were characterized, and the removal effects and reaction kinetics of BPA and EE2 by BMOs under different pH values, initial organic concentrations, and dosages of BMOs were discussed. The results showed that the formation of BMOs was extracellular process, and Mn(II) was oxidized to Mn(III) and Mn(IV) with 23.56% and 76.44%, respectively. The degradation processes of BPA and EE2 by BMOs followed first-order reaction kinetics, and the removal effect decreased with increasing initial BPA/EE2 concentrations and increased with increasing dosages of BMOs. However, the removal effect of BPA by BMOs decreased and then increased with increasing pH, while the removal effect of EE2 by BMOs decreased with increasing pH. Under optimal conditions, the removal efficiency of BPA and EE2 exceeded 98.2% and 94.3%, respectively. Additionally, this study showed that BMOs degraded BPA by coupling, oxidative condensation, substitution, and elimination reactions to obtain sixteen intermediate products and EE2 by substitution and elimination reactions to obtain seven intermediate products.

Generality and diversity on the kinetics, toxicity and DFT studies of sulfate radical-induced transformation of BPA and its analogues

The international campaign to ban bisphenol A (BPA) has resulted in increasing application of BPA substitutes. However, investigations have mainly been confined to the removal of single contaminant from the water, resulting in an inefficient burden. Furthermore, systematic study and synthetical discussion of bisphenol analogues (BPs) kinetics and transformation pathways were largely underemphasized. Chemical oxidation of BPA and four typical alternatives (i.e., bisphenol AF, bisphenol E, bisphenol F and bisphenol S) in a UV-activated persulfate system was examined in this study. The effects of persulfate (PS) dosage, pH and water matrix constituents (i.e., bicarbonate, chloride and natural organic matter) were comprehensively examined using a combination of laboratory experiments and mathematical modeling. According to our findings, the removal characteristics of different BPs employing SO₄•^--induced removal technology, including degradation mechanisms and influencing trends by water matrix, revealed similarly. The second order-rate constants of SO₄•^- reacting with BPs served as the main variables mediating the variation in degradation kinetics. Frontier molecular orbital theory and density functional theory suggested BPs molecules possessed the same susceptible positions to free radicals. In the UV-activated PS process, transformation pathways included hydroxylation, electron-transfer, substitution, and rearrangement triggered by ortho-cleavage, with certain intermediates exhibiting higher toxicity than the parent chemicals. The findings of this study provided valuable information to estimate potential environmental risks of using BPA alternatives.

Bisphenol analogues induced metabolic effects through eliciting intestinal cell heterogeneous response

The metabolic effects of endocrine-disrupting chemicals, such as bisphenol analogues, have drawn increasing attention. Bisphenol A (BPA) usage is associated with the occurrence of many metabolic diseases. With the restricted use of BPA, alternatives like bisphenol F (BPF) and bisphenol AF (BPAF) have been greatly introduced for industrial manufacture, and brings new hazard to public health. To understand how bisphenol analogues induced metabolic effects, zebrafish are continuous exposed to environmental level (0.5 μg/L) of BPA, BPF and BPAF since embryonic stage, and identified hepatic steatosis and insulin resistance at 60-day post fertilization. Hepatic transcriptional profile indicated that pancreatic disease pathways were activated by BPA, but were inhibited by BPF. At the same time, increased lipid secretion and gluconeogenesis pathways in zebrafish liver was found post BPAF exposure. Significant inflammatory response, histological injury and increased mucus secretion was detected in zebrafish intestine post exposure of three bisphenol analogues. Single-cell RNA sequencing of zebrafish intestinal cells revealed activation of lipid uptake and absorption pathways in enterocyte lineages, which well explained the hepatic steatosis induced by BPA and BPF. Besides, genes related to carbohydrate metabolism, diabetes and insulin resistance were activated in intestinal immune cell types by three bisphenol analogues. These findings indicated that BPA and its alternatives could lead to abnormal lipid and carbohydrate metabolism of zebrafish through inducing cell heterogeneous changes in gut, and revealed both molecular and cellular mechanism in mediating this effect.

Self-regeneration hybrid hydrogel for bisphenol a adsorption in water

Hybrid hydrogel was synthesized by immobilizing TiO₂ in polyethylene glycol diacrylate (TiO₂@PEGDA) as an efficient adsorbent with photocatalysis property for bisphenol A (BPA) elimination. TiO₂@PEGDA exhibited spherical and rough structure with limited crystallinity and abundant functional groups. The contact angle increased to 61.96° (TiO₂@PEGDA) from 46.73° (pristine PEGDA), indicating that hydrogel hydrophilicity decreased due to the presence of TiO₂. The swelling capacity of TiO₂@PEGDA (9.0%) was decreased compared with pristine PEGDA (15.6%). Adsorption results demonstrated that the maximum adsorption capacity of TiO₂@PEGDA (101.4 mg/g) for BPA was slightly higher than that of pristine PEGDA (97.68 mg/g). The adsorption capacity was independent with pH below 8 and decreased obviously when the value of pH was higher than 8. The adsorption behavior was fitted well with the pseudo-second-order kinetic and the Langmuir isotherm model. Both ΔG₀ and ΔH₀ were negative, indicating that BPA adsorbed on TiO₂@PEGDA was an exothermic and spontaneous process. Regeneration study was performed by photocatalysis, and the adsorption capacity was 85.6% compared with the initial capacity after four-cycle use, indicating that TiO₂@PEGDA could be recycled without significant adsorption capacity loss. Consequently, TiO₂@PEGDA can serve as an eco-friendly and promising material for efficiently adsorbing BPA with self-clean property.

Systems toxicology approach explores target-pathway relationship and adverse health impacts of ubiquitous environmental pollutant bisphenol A

The effects of environmental chemicals on health outcomes may be underestimated due to deficiency of knowledge regarding the actions of compounds on toxico-pathogenic mechanisms underlying biological systems outcomes. In this regard, the current study aimed to explore the potential target-pathway-disease relationship attributed to bisphenol A (BPA) responses in target tissues. Computational methods including reverse pharmacophore mapping approach, structural similarity based search and kinome wide interaction profiling were employed with molecular docking validation. Gene ontology (GO) enrichment analysis and protein-protein interaction (PPI) network based illustrations were utilized to prioritize target-pathway and disease relationships. Data illustrated that BPA possessed multi-target nature since this chemical potentially interacted with various protein targets where many of these were validated through docking. Potential BPA targets were significantly enriched to various cellular signaling pathways including steroid biosynthesis, peroxisome proliferator-activated receptor gamma (PPARℽ) and cancer. Further, hypertension was prioritized as disease target. In addition, BPA targeted 17 cell signaling kinases encompassed in the human kinome. In addition, inflammatory (5-LO) and apoptosis regulators (Bcl-X and Bcl-2) were also explored as novel targets. Evidence indicates that the multi-target nature and plausible mechanisms underlying BPA actions in a system wide manner aids toward understanding of adverse effects. This observation may lead us to more precise method to elucidate the toxico-pathogenic mechanisms of BPA with an environmental health perspective.

Bisphenol-A analogs induce lower urinary tract dysfunction in male mice

Bisphenol-A (BPA), an estrogenic endocrine disrupting chemical, significantly impacts numerous diseases and abnormalities in mammals. Estrogens are known to play an important role in the biology of the prostate; however, little is known about the role of bisphenols in the etiology of prostate pathologies, including benign prostate hyperplasia (BPH) and associated lower urinary tract dysfunction (LUTD). Bisphenol-F (BPF) and bisphenol-S (BPS) are analogs often used as substitutes for BPA; they are both reported to have in vitro and in vivo estrogenic effects similar to or more potent than BPA. The objective of this study was to assess the role of these bisphenols in the development of LUTD in adult male mice. In adult mice exposed to BPA, BPS or BPF, we examined urinary tract histopathology and physiological events associated with urinary dysfunction. Mice treated with bisphenols displayed increased bladder (p < 0.005) and prostate (p < 0.0001) mass, and there was an increased number of prostatic ducts in the prostatic urethra (p < 0.05) and decreased size of the urethra lumen (p < 0.05) compared to negative controls. After two months of bisphenol exposure, mice displayed notable differences in cystometric tracings compared to controls, consistent with LUTD. Treatment of male mice with all bisphenols also induced voiding dysfunction manifested by detrusor instability and histologic changes in the prostatic urethra of male rodents, consistent with LUTD. Our results implicate BPA and its replacements in the development and progression LUTD in mice and provide insights into the development and progression of BPH/LUTS in men.

The dynamic interplay between AMPK/NFκB signaling and NLRP3 is a new therapeutic target in inflammation: Emerging role of dapagliflozin in overcoming lipopolysaccharide-mediated lung injury

Acute lung injury (ALI) is one the most common causes of morbidity and mortality in critically ill patients. In this study, we examined for first time the role of dapagliflozin (DPGZ) in lipopolysaccharide (LPS)-induced ALI in rats and determined the underlying molecular mechanisms by evaluating the effects of DPGZ on adenosine monophosphate kinase (AMPK), nuclear transcription factor kappa B, nucleotide-binding and oligomerization domain-like receptor 3 inflammasome activation. Treatment of acute lung injured rats with either low dose (5 mg/kg) or high dose (10 mg/kg) DPGZ significantly decreased oxidative stress by decreasing malondialdehyde and nitric oxide tissue levels with a significant increase in spectrophotometric measurements of superoxide dismutase, catalase, and reduced glutathione levels. DPGZ treatment resulted in a significant anti-inflammatory effect as indicated by suppression in myeloperoxidase activity, MCP-1, IL-1β, IL-18, and TNF-α levels. DPGZ treatment also increased p-AMPK/t-AMPK with a significant reduction in NF-kB P65 binding activity and NFĸB p65 (pSer536) levels. These effects of DPGZ were accompanied by a significant reduction in NLRP3 levels and NLRP3 gene expression and a significant decrease in caspase-1 activity, which were also confirmed by histopathological examinations. We conclude that DPGZ antioxidant and anti-inflammatory activity may occur through regulation of AMPK/NFĸB pathway and inhibition of NLRP3 activation. These results suggest that DPGZ represents a promising intervention for the treatment of ALI, particularly in patients with type 2 diabetes.

Ratiometric electrochemical sensor for bisphenol A detection using a glassy carbon electrode modified with a poly(toluidine blue)/gold nanoparticle composite

A ratiometric electrochemical sensor for bisphenol A (BPA) detection is developed using a glassy carbon electrode modified with a poly(toluidine blue)/gold nanoparticle composite (PTB/AuNP/GCE). The ratiometric signal, namely, the oxidation peak current ratio of BPA to PTB, increases linearly with BPA concentration in the 0.2-5.0 μM range, with a detection limit of 0.15 μM. The electrochemical mechanism of BPA is studied at the PTB/AuNP/GCE, and the results show that BPA undergoes an electrooxidation process of two electrons and two protons at the PTB/AuNP/GCE. The proposed sensor has high sensitivity, high stability and good selectivity. The application of BPA in water samples is successfully verified using the proposed ratiometric electrochemical sensor.

Bisphenol A derivatives act as novel coactivator-binding inhibitors for estrogen receptor β

Bisphenol A and its derivatives are recognized as endocrine disruptors based on their complex effects on estrogen receptor (ER) signaling. While the effects of bisphenol derivatives on ERα have been thoroughly evaluated, how these chemicals affect ERβ signaling is less well understood. Herein, we sought to identify novel ERβ ligands using a radioligand competitive binding assay to screen a chemical library of bisphenol derivatives. Many of the compounds identified showed intriguing dual activities as both ERα agonists and ERβ antagonists. Docking simulations of these compounds and ERβ suggested that they bound not only to the canonical binding site of ERβ but also to the coactivator binding site located on the surface of the receptor, suggesting that they act as coactivator-binding inhibitors (CBIs). Receptor-ligand binding experiments using WT and mutated ERβ support the presence of a second ligand-interaction position at the coactivator-binding site in ERβ, and direct binding experiments of ERβ and a coactivator peptide confirmed that these compounds act as CBIs. Our study is the first to propose that bisphenol derivatives act as CBIs, presenting critical insight for the future development of ER signaling-based drugs and their potential to function as endocrine disruptors.

Environmental obesogens (bisphenols, phthalates and parabens) and their impacts on adipogenic transcription factors in the absence of dexamethasone in 3T3-L1 cells

Endocrine-disrupting chemicals (EDCs) are exogenous compounds that are capable of blocking or mimicking the action of bioidentical hormones. Obesogenic EDCs, commonly called obesogens, play an important role in adipogenesis. This study was carried out to determine the effects of select obesogens and their alternatives on adipogenesis in 3T3-L1 cells under dexamethasone (DEX)-free conditions. Preadipocytes were treated with a cocktail of 3-isobutyl-1-methylxanthine (IBMX) and insulin to which an obesogen (viz., bisphenol A (BPA) or its analogs BPS and BPF; dioctyl terephthalate; tris (2-ethylhexyl) trimellitate; or various parabens) had been added. A mixture containing IBMX, insulin, and DEX, which constitute the typical hormonal cocktail required for adipocyte differentiation, was used as the control against which the other groups were measured. The obesogens and the PBA analogs all had evident adipogenic effects under DEX-free conditions, as was determined by estimating the lipid accumulation levels in the cells using Oil Red O staining. Furthermore, the expression of adipogenic transcription factors (CCAAT/enhancer-binding protein-alpha, peroxisome proliferator-activated receptor-gamma, and adipocyte protein 2) was induced by 20 μM of BPA, BPS, or BPF at both the mRNA and protein levels, as determined through reverse transcription-polymerase chain reaction and western blot assays. Taken together, the results reveal that adipocyte differentiation can be induced by obesogens and their alternatives in the absence of DEX.

Bisphenol A Removal by the Fungus Myrothecium roridumIM 6482-Analysis of the Cellular and Subcellular Level

Bisphenol (BPA) is a key ingredient in the production of epoxy resins and some types of plastics, which can be released into the environment and alter the endocrine systems of wildlife and humans. In this study, the ability of the fungus M. roridumIM 6482 to BPA elimination was investigated. LC-MS/MS analysis showed almost complete removal of BPA from the growth medium within 72 h of culturing. Products of BPA biotransformation were identified, and their estrogenic activity was found to be lower than that of the parent compound. Extracellular laccase activity was identified as the main mechanism of BPA elimination. It was observed that BPA induced oxidative stress in fungal cells manifested as the enhancement in ROS production, membranes permeability and lipids peroxidation. These oxidative stress markers were reduced after BPA biodegradation (72 h of culturing). Intracellular proteome analyses performed using 2-D electrophoresis and MALDI-TOF/TOF technique allowed identifying 69 proteins in a sample obtained from the BPA containing culture. There were mainly structural and regulator proteins but also oxidoreductive and antioxidative agents, such as superoxide dismutase and catalase. The obtained results broaden the knowledge on BPA elimination by microscopic fungi and may contribute to the development of BPA biodegradation methods.

Chitosan nanoparticles alleviated endocrine disruption, oxidative damage, and genotoxicity of Bisphenol-A- intoxicated female African catfish

Bisphenol-A (BPA) is widely used in production of plastic products. It can reach the ecosystems affecting aquatic organisms most likely fishes. The purpose of this study was to study the toxic effects of BPA on the biochemical variables and oxidative stress in female African catfish, Clarias gariepinus and to estimate the protective role of chitosan nanoparticles (CSNPs) against BPA toxicity. Five groups in triplicates of fish were divided as follows: group I was control, group II was treated with CSNPs (0.66 ml/L), group III was exposed to BPA (1.43 μg/L), group IV was treated with BPA (1.43 μg/L) plus CSNPs (0.33 ml/L), and group V was treated with BPA (1.43 μg/L) plus CSNPs (0.66 ml/L) for 30 days. Blood and liver tissue samples were collected at the end of experiment for the biochemical and oxidative stress biomarkers analyses. Results exhibited that serum Follicle Stimulating Hormone (FSH) and 17-β Estradiol (E2) were significantly decreased in female catfish. While, serum Testosterone (T.) and Luteinizing Hormone (LH) were increased after exposure to BPA. Marked increment in superoxide dismutase (SOD) and malondialdehyde (MDA) levels of hepatic tissue of catfish exposed to BPA. Furthermore, significant reduction in hepatic catalase (CAT), glutathione peroxidase (GSH-px), total antioxidant capacity (TAC), reduced glutathione (GSH), and glutathione S-transferase (GST) levels were decreased significantly in BPA-exposed catfish compared to the control group. However, administration of female C. gariepinus with the low and high doses (0.33 ml/L and 0.66 ml/L) of CNPs restored the biochemical parameters to be close to the normal values of the control group and also, reduced oxidative stress induced by BPA toxicity. This improvement was evident in fish administrated with the high CSNPs dose (0.66 ml/L) compared to catfish exposed to BPA in group (III). Furthermore, the percentage of hepatic DNA damage was detected in group III exposed to BPA alone. However, it was declined after co- administration with both the low and high doses of CSNPs. The study has revealed that treatment with CSNPs has antagonistic functions against the toxicity of BPA in female African catfish.

In Vitro Screening of 21 Bisphenol A Replacement Alternatives: Compared with Bisphenol A, the Majority of Alternatives Are More Cytotoxic and Dysregulate More Genes in Avian Hepatocytes

An avian in vitro screening approach was used to determine the effects of 21 bisphenol A (BPA) alternatives. Cytotoxicity and dysregulation of genes associated with estrogen response and other toxicologically relevant pathways evoked by these alternatives were compared with BPA. Most of the BPA alternatives (15/21) were equally or more cytotoxic than BPA in chicken embryonic hepatocytes; variability in cell viability was associated with chemical structure and the log octanol-water partition coefficient (logP) values. A negative linear relationship (r ²  = 0.745; p = 0.49^-07 ; n = 18) was observed between logP and the log median lethal concentration (logLC50) values. The least cytotoxic BPA alternatives elicited the greatest gene dysregulation and, overall, most of the alternatives altered more genes than BPA (measured with a custom polymerase chain reaction array). This overall approach shows promise for use as a screen for hazard-based prioritization of BPA replacement alternatives and to ideally identify those that may be less harmful and/or require additional toxicity testing. Environ Toxicol Chem 2021;40:2026-2033. © 2021 Her Majesty the Queen in Right of Canada Environmental Toxicology and Chemistry © 2021 SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.