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.
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•Sunlight-driven TiO2-BiVO4-PI photoelectrocatalyst was prepared and characterized.•BiVO4 and PI form a surface-to-surface contact Z-scheme.•The higher charge separation efficiency with a strong redox ability was confirmed.•Various BPs were efficiently degraded by TiO2-BiVO4-PI heterostructure.•The toxicity of the BPs and intermediates showed a decrease trend in this PEC system.
BACKGROUND: Experimental laboratory evidence suggests that bisphenol A (BPA), an endocrine disruptor, is a neurodevelopmental toxicant However) there have been limited and inconclusive results with ...respect to sex-specific BPA effects on child behavior. OBJECTIVE: We examined the association between prenatal BPA exposure and child behavior, adjusting for postnatal BPA exposure and hypothesizing sex-specific effects. METHODS: We followed African-American and Dominican women and their children from pregnancy to child's age 5 years, collecting spot urine samples from the mothers during pregnancy (34 weeks on average) and from children between 3 and 4 years of age to estimate BPA exposure. We assessed child behavior between 3 and 5 years of age using the Child Behavior Checklist (CBCL) and used generalized linear models to test the association between BPA exposure and child behavior, adjusting for potential confounders. RESULTS: The analysis was conducted on 198 children (87 boys and 111 girls). Among boys, high prenatal BPA exposure (highest quartile vs. the lowest three quartiles) was associated with significantly higher CBCL scores (more problems) on Emotionally Reactive 1.62 times greater; 95% confidence interval (CI): 1.13, 2.32 and Aggressive Behavior syndromes (1.29 times greater; 95% CI: 1.09,1.53). Among girls, higher exposure was associated with lower scores on all syndromes, reaching statistical significance for Anxious/Depressed (0.75 times as high; 95% CI: 0.57, 0.99) and Aggressive Behavior (0.82 times as high; 95% CI: 0.70, 0.97). CONCLUSION: These results suggest that prenatal exposure to BPA may affect child behavior, and differently among boys and girls.
Concentrations of eight bisphenol analogues (BPs) including BPA, BPS, and BPF were determined in surface waters collected from select rivers in Japan, Korea, China, and India. BPA was found at a ...concentration in the range of several tens to several hundreds of nanograms per liter in most of the rivers surveyed and some of the highest concentrations (54–1950ng/L) were found in rivers in Chennai, India. Concentrations of BPF were one to two orders of magnitude higher than those of BPA in river and sea waters collected from Japan, Korea and China, which suggested that BPF is a major contaminant in surface waters in several Southeast Asian countries. BPF concentrations as high as 2850ng/L were found in the Tamagawa River in Japan. The flux of BPs through riverine discharges into Tokyo Bay was calculated to be approximately 5.5t per year. Based on the flux estimates and the mass of BPF found in water column and sediment in Tokyo Bay, it was found that BPF degrades faster than BPA in the environment. Elevated concentrations of BPF found in surface waters suggest the need for further studies to determine the fate and toxicity of this compound.
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•BPA, BPS, and BPF were measured in surface waters in four Asian countries.•BPA was found at several tens to hundreds of ng/L concentrations.•BPF was the major bisphenol in rivers and the levels exceeded those of BPA.•The riverine flux of BPA, BPS, and BPF was calculated for Tokyo Bay.
Bisphenol a (BPA) is a high production volume chemical that is frequently used to manufacture epoxy resins and polycarbonate plastics. BPA-containing products are now pervasive, and as a result, ...biomonitoring studies report widespread exposure in > 90% of adults, adolescents, and children. Both epidemiological and experimental studies have reported associations between BPA exposure and adverse cardiovascular health outcomes. With increasing concerns regarding BPA exposure, a few structurally similar bisphenol chemicals have been introduced as replacements, including bisphenol s (BPS) and bisphenol f (BPF). In accordance with the recently established “
Key characteristics of cardiovascular toxicants
”, we reviewed the literature to highlight the immediate effects of bisphenol chemicals on (1) cardiac excitability, and (2) contractility and relaxation. BPA inhibits key cardiac ion channels, impairs cardiac excitability, and acts as a more potent inhibitor as compared to BPF and BPS. Through the inhibition of calcium current, some studies report that bisphenol chemicals can act as negative inotropic agents. Yet, others suggest that low dose exposures may increase contractility and precipitate triggered arrhythmias via the phosphorylation of key calcium handling proteins. Accordingly, we propose additional considerations for future work to comprehensively address the cardiac safety profile of BPA, as compared to replacement chemicals.
Bisphenol A (BPA) is a well-known endocrine disruptor that imperfectly mimics the effects of physiologic estrogens via membrane-bound estrogen receptors (mERα, mERβ, and GPER/GPR30), thereby ...initiating nongenomic signaling. Bisphenol S (BPS) is an alternative to BPA in plastic consumer products and thermal paper.
To characterize the nongenomic activities of BPS, we examined signaling pathways it evoked in GH3/B6/F10 rat pituitary cells alone and together with the physiologic estrogen estradiol (E2). Extracellular signal-regulated kinase (ERK)- and c-Jun-N-terminal kinase (JNK)-specific phosphorylations were examined for their correlation to three functional responses: proliferation, caspase activation, and prolactin (PRL) release.
We detected ERK and JNK phosphorylations by fixed-cell immunoassays, identified the predominant mER initiating the signaling with selective inhibitors, estimated cell numbers by crystal violet assays, measured caspase activity by cleavage of fluorescent caspase substrates, and measured PRL release by radioimmunoassay.
BPS phosphoactivated ERK within 2.5 min in a nonmonotonic dose-dependent manner (10-15 to 10-7 M). When combined with 10-9 M E2, the physiologic estrogen's ERK response was attenuated. BPS could not activate JNK, but it greatly enhanced E2-induced JNK activity. BPS induced cell proliferation at low concentrations (femtomolar to nanomolar), similar to E2. Combinations of both estrogens reduced cell numbers below those of the vehicle control and also activated caspases. Earlier activation of caspase 8 versus caspase 9 demonstrated that BPS initiates apoptosis via the extrinsic pathway, consistent with activation via a membrane receptor. BPS also inhibited rapid (≤ 1 min) E2-induced PRL release.
BPS, once considered a safe substitute for BPA, disrupts membrane-initiated E2-induced cell signaling, leading to altered cell proliferation, cell death, and PRL release.
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•Amorphous boron exhibited outstanding catalytic activity and superior stability for peroxymonosulfate activation.•Effective degradation of bisphenol S was achieved in the amorphous ...boron/peroxymonosulfate oxidative system.•The corresponding catalytic oxidation mechanism was elucidated.
Recently, tremendous efforts have been devoted to developing carbon-based metal-free catalysts as an alternative to metal-based catalysts for remediation of emerging contaminants. However, further investigations have demonstrated that the durability of carbocatalysts is poor. Therefore, it is extremely desirable to seek a novel metal-free catalyst with high efficiency and superb stability. Herein, we first discovered that amorphous boron (A-boron) can be used as a metal-free catalyst for peroxymonosulfate (PMS) activation to produce free radicals for effective degradation of bisphenol S (BPS), which is a newly-occurring estrogenic endocrine-disrupting chemical. It exhibited outstanding catalytic activity and superior stability as comparing to metal-based and metal-free carbon-based catalysts. Moreover, many other typical organic pollutants in water such as bisphenol F, sulfamethoxazole, rhodamine B and methyl orange can also be effectively decomposed in A-boron/PMS oxidative system. The effects of reaction parameters on BPS degradation were systematically investigated. The catalytic oxidation mechanism was proposed. The intriguing catalytic feature of A-boron discovered in this study will provide new opportunities for the future development of A-boron based materials with promising applications in water remediation.
In order to understand the negative effects of bisphenol A (BPA) alternatives comprehensively, zebrafish embryos were used to assess the lethality, developmental effects, and estrogenic activity of ...bisphenol analogues. The in silico estrogenic activities of bisphenol analogues were assayed by binding simulation. According to our results, the lethality of bisphenol analogues decreased in order of bisphenol AF (BPAF) > BPA > bisphenol F (BPF) > bisphenol S (BPS). BPAF and BPF induced significant effects on zebrafish embryos, including decreased heart rate, hatching inhibition, and teratogenic effects. The binding potentials of bisphenol analogues toward zebrafish ERs (zfERS) decreased in the following order: BPAF > BPA > BPF > BPS. Among the three subtypes of zfERs, zfERβ2 showed the highest binding activity toward the bisphenols, followed by zfERα and zfERβ1. In vivo estrogenic activity tests showed that BPAF, BPA, and BPF significantly enhanced the protein levels of ERα along with the mRNA levels of esr1, esr2a, esr2b, and vtg1 in zebrafish embryos. Esr2b showed the strongest response to BPAF and BPA exposure among the three esrs. In contrast, BPS did not significantly regulate ER protein level or ER transcription. In conclusion, BPAF showed the highest lethality, developmental effects, and estrogenic activity (both in silico and in vivo) followed by BPA and BPF. BPS showed the weakest toxicity and estrogenic activity. zfERβ2 might act as the main target among the three ER subtypes of zebrafish after exposure to BPAF and BPA.
Background: Bisphenol A (BPA) is the principal constituent of baby bottles, reusable water bottles, metal cans, and plastic food containers. BPA exerts estrogen-like activity by interacting with the ...classical estrogen receptors (ERα and ERß) and through the G protein-coupled receptor (GPR30/GPER). In this regard, recent studies have shown that GPER was involved in the proliferative effects induced by BPA in both normal and tumor cells. Objectives: We studied the transduction signaling pathways through which BPA influences cell proliferation and migration in human breast cancer cells and cancer-associated fibroblasts (CAFs). Methods and results: We used as a model system SKBR3 breast cancer cells and CAFs that lack the classical ERs. Specific pharmacological inhibitors and gene-silencing procedures were used to show that BPA induces the expression of the GPER target genes c-FOS, EGR-1, and CTGF through the GPER/EGFR/ERK transduction pathway in SKBR3 breast cancer cells and CAFs. Moreover, we observed that GPER is required for growth effects and migration stimulated by BPA in both cell types. Conclusions: Results indicate that GPER is involved in the biological action elicited by BPA in breast cancer cells and CAFs. Hence, GPER-mediated signaling should be included among the transduction mechanisms through which BPA may stimulate cancer progression.
The present work deals with the development of bisphenol‐BA based benzoxazines and to study their behavior toward utilization for thermal, high‐dielectric, low‐dielectric, and anti‐corrosion ...applications. A new type of bifunctional benzoxazine resins were synthesized using bisphenol‐BA with different types of amines and characterized using FTIR, 1H‐NMR spectra, DSC, and TGA techniques. In the present study, thermally stable bisphenol‐BA with trifluoromethylaniline benzoxazine (BBA‐tfma) and bisphenol‐BA with furfurylamine benzoxazine (BBA–ffa) were selected as matrices for the preparation of composites with SBA‐15, bio‐silica (from Bermuda grass) and reduced graphene oxide. The results indicated that the poly(BBA‐tfma) with 5 wt% SBA‐15 composites and poly(BBA‐ffa) with 10 wt% bio‐silica composites showed the lowest dielectric constant value of 1.71 and 1.87, respectively. While in contrast, the 5 wt% of reduced graphene oxide (rGO) reinforced poly(BBA‐tfma) exhibits highest value of dielectric constant (k = 8.49). Results from corrosion studies ascertain that the bisphenol‐BA with aminoethoxyethanol benzoxazine, that is, poly(BBA‐aee) possess better mild steel corrosion protection behavior than that of other benzoxazines. Data resulting from different studies indicate that the bisphenol‐BA‐based benzoxazines and their composites can be effectively used for different industrial applications.
Development of new bisphenol‐BA‐based polybenzoxazine composites and to study their behavior toward utilization of thermal, high‐dielectric, low‐dielectric, and anti‐corrosion applications.
Bisphenols, estrogenic endocrine-disrupting chemicals, disrupt at least one of three endocrine pathways (estrogen, androgen, and thyroid). 17β-Hydroxysteroid dehydrogenase 1 (17β-HSD1) is a ...steroidogenic enzyme that catalyzes the activation of estradiol from estrone in human placenta and rat ovary. However, whether bisphenols inhibit 17β-HSD1 and the mode of action remains unclear. This study we screened 17 bisphenols for inhibiting human 17β-HSD1 in placental microsomes and rat 17β-HSD1 in ovarian microsomes and determined 3D-quantitative structure-activity relationship (3D-QSAR) and mode of action. We observed some bisphenols with substituents were found to significantly inhibit both human and rat 17β-HSD1 with the most potent inhibition on human enzyme by bisphenol H (IC50 = 0.90 μM) when compared to bisphenol A (IC50 = 113.38 μM). Rat enzyme was less sensitive to the inhibition of bisphenols than human enzyme with bisphenol H (IC50 = 32.94 μM) for rat enzyme. We observed an inverse correlation between IC50 and hydrophobicity (expressed as Log P). Docking analysis showed that they bound steroid-binding site of 17β-HSD1. The 3D-QSAR models demonstrated that hydrophobic region, hydrophobic aromatic, ring aromatic, and hydrogen bond acceptor are key factors for the inhibition of steroid synthesis activity of 17β-HSD1.
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•BPA analogues have been widely used but disrupt at least one of three endocrine pathways.•Bisphenols inhibit both human and rat 17β-HSD1. Rat enzyme was less sensitive than human enzyme.•Docking analysis showed that they bound steroid-binding site of 17β-HSD1.•3D-QSAR models demonstrated HBA, HY, RA, HYA are key factors.•An inverse correlation between IC50 and hydrophobicity (expressed as Log P).
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