Search Results (67)

Background: Bisphenol A (BPA) release from resin-based dental materials is a growing concern due to its potential endocrine-disrupting effects, particularly in pediatric patients. This in vitro study evaluated cumulative BPA release and elution kinetics from commonly used pediatric resin-based materials, due to the limited evidence available. Methods: Three restorative materials (Clearfil Majesty ES-2, Estelite Sigma Quick, and Stela Automix) and one orthodontic material (Transbond XT) were investigated. Eighteen disk-shaped specimens (5.5 mm in diameter and 2 mm in thickness) were prepared for each material and immersed in artificial saliva (pH 6.8) at 37 °C for 1, 7, and 28 days. BPA concentrations were quantified using liquid chromatography–tandem mass spectrometry (LC–MS/MS). BPA release kinetics were evaluated during the early (1–7 days) and late (7–28 days) release phases. Results: All investigated materials released measurable BPA concentrations, with cumulative BPA release progressively increasing up to 28 days. Clearfil Majesty ES-2 and Estelite Sigma Quick exhibited the highest cumulative BPA concentrations, whereas Stela Automix showed markedly lower values. Transbond XT also demonstrated measurable BPA release. For all materials, BPA release kinetics were significantly higher during the early phase than during the late phase (p < 0.001), indicating a non-linear release behavior over time. Conclusions: BPA release from pediatric restorative and orthodontic resin-based materials is material-dependent and characterized by progressive cumulative accumulation associated with significantly higher early-phase release rates. These findings highlight the importance of assessing the safety of resin-based materials used in pediatric dentistry. Full article

BisphenolA (BPA) is a common endocrine disruptor that impairs male fertility through oxidative stress and alterations in membrane lipids. This study evaluated the protective effects of Myrtus communis L. essential oil (EOMC) on BPA-induced sperm toxicity in Wistar rats in vitro. BPA significantly decreased sperm motility and viability. It also increased lipid peroxidation, depleted thiols, and reduced the activity of antioxidant enzymes (SOD, CAT-like and GPx-like). Concomitant treatment with low and intermediate doses of EOMC (0.5–1 µL/mL) restored sperm function, reduced oxidative stress, and preserved membrane phospholipids. However, the highest dose (5 µL/mL) further impaired sperm function and disrupted membrane phospholipids. BPA also altered amino acid profiles and accumulated intracellularly, effects partially reversed by EOMC, which redistributed free BPA into the culture medium. Bioavailability analysis revealed selective absorption of α-pinene, while d-limonene and 1,8-cineole were undetectable. Molecular modeling indicated strong binding of BPA to antioxidant enzymes, potentially disrupting their structure and activity. Overall, these results show that EOMC protects sperm from BPA-induced damage in a dose-dependent manner through antioxidant, membrane-stabilizing, and redistribution mechanisms. This highlights its potential application in phytotherapy for male reproductive health. Full article

Resin-based dental composites are widely used in restorative dentistry; however, concerns persist regarding their potential release of Bisphenol-A (BPA), a compound with recognized endocrine-disrupting activity. This in vitro study evaluated the time-dependent release of BPA from four contemporary resin-based dental filling composites immersed in artificial saliva under different thermal conditions. Disk-shaped specimens (5.5 mm diameter and 2 mm thickness) of Estelite Sigma Quick, Clearfil Majesty ES-2, Omnichroma Flow, and Luna 2 were incubated in artificial saliva at physiological pH (6.8) at 37 °C and 44 °C. BPA concentrations were quantified after 1, 7, and 28 days using a validated UHPLC–MS/MS method. BPA release was observed for all materials except Luna 2, for which it remained below the limit of quantification (LOQ) at all time points and temperatures. Across all BPA-releasing composites, the highest concentrations were observed after 1 day of immersion, particularly at 44 °C. Estelite Sigma Quick exhibited the highest BPA release, followed by Clearfil Majesty ES-2 and Omnichroma Flow. BPA release decreased progressively over time for all materials. Statistical analysis confirmed significant effects of material type, temperature, and exposure duration on BPA release (p < 0.001). Within the limitations of this in vitro study, BPA release appears to be material-dependent and influenced by thermal conditions and immersion time. Although absolute BPA concentrations were low, these findings highlight the importance of material-specific evaluation and continued monitoring of potential sources of cumulative BPA exposure from restorative dental materials. Full article

Bisphenol-A (BPA) and butylparaben (BP) are recognized as emerging contaminants due to their extensive use in plastics and personal care products, posing significant risks to ecosystems and human health. Understanding their transport behavior is vital for predicting environmental fate and designing mitigation measures. This study quantifies the diffusion coefficients of BPA and BP under infinite dilution conditions to simulate realistic environmental scenarios. Laboratory experiments employed a UV-Visible spectrophotometer to monitor concentration changes over time at four initial BP concentrations (0.0005–0.0025 M) and at temperatures between 294.85 K and 304.15 K. Experimental data show that BP concentrations at lower initial values (0.0005 M and 0.00075 M) remained constant, indicating minimal diffusion. Theoretical estimations using the Stokes–Einstein equation yielded diffusion coefficients at 299.38 K of 1.51 × 10⁻¹³ m²/s for BP and 8.47 × 10⁻¹⁴ m²/s for BPA. The Wilke–Chang equation estimated higher values: 1.21 × 10⁻¹⁰ m²/s for BP and 1.18 × 10⁻¹⁰ m²/s for BPA at the same temperature. Results confirm that temperature increases enhance diffusion, while molecular size differences cause BP to diffuse faster than BPA. The robust experimental dataset produced here supports the refinement of predictive models for contaminant mobility. These insights are critical for risk assessment and for developing targeted strategies to minimize the persistence and spread of endocrine-disrupting chemicals in aquatic and terrestrial systems. Full article

Growing concerns over the toxicity and sustainability of dental materials have driven the search for alternatives to bisphenol A-glycidyl methacrylate (Bis-GMA), a widely used dental resin monomer associated with health risks. This study highlights the potential of less health-hazardous dental formulations by incorporating high-value materials derived from the glycolysis of poly(ethylene terephthalate) (PET). Dimethacrylated oligoesters (PET-GLY-DM), synthesized through the methacrylation of PET glycolysis products, were blended with Bis-GMA and triethylene glycol dimethacrylate (TEGDMA), toward the gradual replacement of Bis-GMA content. The innovative PET-GLY-DM-based resins exhibited a higher degree of conversion compared to traditional Bis-GMA/TEGDMA formulations, as measured by FTIR spectroscopy, accompanied by an increase in polymerization shrinkage, evaluated via a linear variable displacement transducer system. While the incorporation of PET-GLY-DM slightly reduced flexural strength and elastic modulus, it significantly decreased water sorption, resulting in a smaller reduction in mechanical properties after water immersion for 7 days at 37 °C and improved long-term performance. Furthermore, PET-GLY-DM resins exhibited low bisphenol-A (BPA) release measured with HPLC. It was thus confirmed that PET-GLY-DM resins derived from the glycolysis of PET wastes represent a promising alternative to conventional light-cured dental resins, offering reduced BPA release and improved water resistance. Full article

Gestational diabetes mellitus (GDM) requires lifestyle changes that may alter exposure to endocrine-disrupting chemicals (EDCs). This study aimed to assess maternal and fetal exposure to EDCs—including bisphenol-A (BPA), monoethyl phthalate (MEP), and perfluorooctanoic acid (PFOA)—during the COVID-19 pandemic and to evaluate their association with fetal birthweight. Maternal urine (second and third trimester) and paired cord blood samples were analyzed from 58 GDM and 118 non-GDM pregnancies using UPLC-MS/MS. Significant correlations were found between maternal urine and cord blood levels of BPA and MEP. Cord blood BPA levels were significantly lower in GDM mothers (0.35 vs. 0.72 μg/L, p < 0.05), suggesting reduced exposure due to dietary interventions. However, maternal urinary BPA levels in GDM pregnancies were positively associated with fetal birthweight (β = 2.69, p < 0.05), indicating increased susceptibility to obesogenic effects. PFOA was present in all cord blood but only 41% of maternal urine samples. These findings underscore the dual impact of GDM-related lifestyle changes: reduced EDC transfer to the fetus, yet persistent metabolic vulnerability. Full article

Recently, toxicological and epidemiological research has provided strong support for the unfavorable effects of bisphenol-A (BPA, 2,2′-bis(4-hydroxyphenyl) propane) on myogenesis and its underlying mechanisms. Researchers have therefore been looking for new strategies to prevent or mitigate these injurious effects of BPA on the human body. It has been found that plant extracts may act as potential therapeutic agents or functional foods, preventing human diseases caused by BPA. We previously reported that Ficus lindsayana (FL) extract exhibits anti-inflammation activity in macrophages via suppressing the expression of inflammation-related molecules and anti-insulin resistance in inflammation-treated adipocytes. In this study, we investigated whether Ficus lindsayana leaf extract (FLLE) protects C2C12 mouse myoblasts against the suppressive effects of BPA on myogenic differentiation. The viability of BPA-stimulated C2C12 myoblasts was significantly increased when co-treated with FLLE (200 µg/mL), suggesting that the extract may lessen the inhibitory effects of BPA on cell division. We also found that FLLE significantly increased neo-myotube formation by inducing the fusion of myoblasts into multinucleated myotubes when compared to the BPA-treated control cells, without impacting cell viability. In addition, the levels of myogenin and myocyte enhancer factor 2A (MEF2A), which are crucial markers and regulators of myogenesis, were markedly increased by the addition of FLLE (50 µg/mL) to the BPA-treated C2C12 cells. This finding suggests that FLLE effectively improved myogenic differentiation in BPA-exposed myoblasts. FLLE treatment (50 µg/mL) significantly raised total Akt protein levels in the BPA-treated C2C12 cells, enhancing protein phosphorylation. In addition, FLLE (50 µg/mL) obviously increased the phosphorylation levels of p70S6K and 4E-BP1, key downstream targets of the Akt/mTOR signaling cascade, by elevating total p70S6K and 4E-BP1 levels. These results suggest that FLLE diminishes the decline in myogenic differentiation induced by BPA via the regulation of the myocyte differentiation-related signaling pathway. The information obtained from this study demonstrates the health benefits of this plant, which warrants further investigation as an alternative medicine, functional ingredient, or food supplement that can prevent the negative health effects of BPA or other toxicants. Full article

The ubiquitous presence of plastics represents a global threat for all ecosystems and human health. In this study, we evaluated, in vitro and in vivo, the genotoxic potential of different concentrations of polystyrene microplastics (PS-MPs) and their possible synergistic interactions with bisphenol-A (BPA). For the in vitro and the in vivo assays, we used human lymphocytes and hemocytes from Lymnaea stagnalis, respectively. The genomic damage was evaluated by the micronucleus assay, and differences in eggs laid and growth of L. stagnalis were also evaluated. In human lymphocytes, PS-MPs alone at the concentration of 200 μg/mL and in association with BPA 0.100 µg/mL significantly increased the frequencies of micronuclei and nuclear buds, indicating a possible in vitro genotoxic additive action of these two compounds. Vice versa, PS-MPs did not result in genotoxicity in hemocytes. Our results indicated that PS-MPs have genotoxic properties only in vitro and at a concentration of 200 µg/mL; moreover, this compound could intensify the genomic damage when tested with BPA, indicating possible cumulative effects. Finally, PS significantly reduced the growth and the number of laid eggs in L. stagnalis. Full article

This study investigates the correlation between the interface structure and macroscopic dielectric properties of polymer-based nanocomposite materials. Utilizing bisphenol-A (BPA) epoxy resin (EP) as the polymer matrix and the commonly employed layered phyllosilicate montmorillonoid (MMT) as the nanometer-scale dispersive phase, nano-MMT/EP composites were synthesized using composite technology. The microstructure of the composite samples was characterized through XRD, FTIR, SEM, and TEM. Changes in the morphology of the nanocomposite interface were observed with varying MMT content, subsequently impacting dielectric polarization and loss. Experimental measurements of the dielectric spectrum of the nano-MMT/EP were conducted, and the influence of the material interface, at different nano-MMT contents, on the dielectric relaxation was analyzed. The study delves into the effect of the nanocomposite interface structure on ion dissociation and migration barriers, exploring the ionic conductivity of nano-MMT/EP. Lastly, an analysis of the impact of different nano-MMT contents on the dielectric conductivity is presented. From the experimental results, the arranging regularity of polymer molecules in the interface area raises. In the matrix, the ion migration barriers decrease significantly. The higher the MMT content in the interface, the lower the migration barrier is. Until the MMT content exceeds the threshold, the agglomerated micro-particles form, which decreases the polymers’ space distribution regularity, and the ions migration barrier raises. According to the changes in the rule of the ions migration barrier with the composite interface structure content, the reason for dielectric conductivity changes can be judged. Full article

Bisphenol-A (BPA), a synthetic compound ubiquitously present in the environment, can act as an endocrine disruptor by binding to both canonical and non-canonical estrogen receptors (ERs). Exposure to BPA has been linked to various cancers, in particular, those arising in hormone-targeted tissues such as the breast. In this study, we evaluated the effect of BPA intake through drinking water on ErbB2/neu-driven cancerogenesis in BALB–neuT mice, transgenic for a mutated ErbB2/neu receptor gene, which reproducibly develop carcinomas in all mammary glands. In this model, BPA accelerated mammary cancerogenesis with an increase in the number of tumors per mouse and a concurrent decrease in tumor-free and overall survival. As assessed by immunohistochemistry, BALB–neuT tumors were ER-negative but expressed high levels of the alternative estrogen receptor GPR30, regardless of BPA exposure. On the other hand, BPA exposure resulted in a marked upregulation of progesterone receptors in preinvasive tumors and of Ki67, CD31, and phosphorylated Akt in invasive tumors. Moreover, based on several infiltration markers of immune cells, BPA favored an immunosuppressive tumor microenvironment. Finally, in vitro cell survival studies performed on a cell line established from a BALB–neuT breast carcinoma confirmed that BPA’s impact on cancer progression can be particularly relevant after chronic, low-dose exposure. Full article

Bisphenol-A (BPA) is a xenoestrogen widely used as a synthetic precursor of resin monomers. There is arise need to acquire BPA-free resin-matrix composites to prevent the health effects of BPA. Six composites with distinctive manufacturer specifications were considered to evaluate the degree of release of BPA and bisphenol A-Diglycidyl Methacrylate (Bis-GMA) in a dental composite. The light-cured resin-matrix specimens (n = 5 for each composite type) were incubated at 37 °C in 1 mL of a 75% ethanol–water solution in a sealed amber glass vial for 7 days. The 75% ethanol–water solution was replaced daily and immediately frozen (−20 °C) until liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. BPA was not detected in any studied resin-based materials. However, Bis-GMA was detected in almost all the studied samples during the experiment, except AF and BF. The highest Bis-GMA concentration was released from ED at 67.43 ng/mL, followed by BE, FS, and NC with 40.75 ng/mL, 8.30 ng/mL, and 0.94 ng/mL, respectively. There is a clear need for more precise and standardized analytical methods to assess the short- and long-term release of resin-based materials. Furthermore, manufacturers should be obliged to provide complete details of the chemical composition of dental products and to promote the development of materials without estrogenic potential. Full article

In this work, the implementation of an electrochromic device (10 cm × 10 cm in size) for energy saving applications has been presented. As electrochromic system has been used with an electrochromic solution (ECsol) made by ethyl viologen diperchlorate [EV(ClO₄)₂], 1,1′-diethyl ferrocene (DEFc) and propylene carbonate (PC), as solvent. The final system has been obtained by mixing the ECsol, described above, with a polymeric system made by Bisphenol-A glycerolate (1 glycerol/phenol) diacrylate (BPA) and 2,2-Dimethoxy-2-phenylacetophenone (Irgacure 651) in a weight percentage equal to 60:40% w/w, respectively. Lithography has been used to make a spacer pattern with a thickness of about 15–20 µm between the two substrates. Micro-Raman spectroscopy confirmed the presence of the EV^•+ as justified by the blue color of the electrochromic device in the ON state. Electrochemical and optical properties of the electrochromic device have been studied. The device shows reversible electrochromic behavior as confirmed by cyclic color variation due to the reduction and oxidation process of the EV²⁺/EV^•+ couple. The electrochromic device shows a variation of the % transmittance in the visible region at 400 nm of 59.6% in the OFF state and 0.48% at 3.0 V. At 606 nm the transmittance in the bleached state is 84.58% in the OFF state and then decreases to 1.01% when it is fully colored at 3.0 V. In the NIR region at 890 nm, the device shows a transmittance of 74.3% in the OFF state and 23.7% at 3.0 V while at 1165 nm the values of the transmittance changed from 83.21% in the OFF state to 1.58% in the ON state at 3.0 V. The electrochromic device shows high values of CCR% and exhibits excellent values of CE in both visible and near-infrared regions when switched between OFF/ON states. In the NIR region at 890 nm, electrochromic devices can be used for the energy-saving of buildings with a promising CE of 120.9 cm²/C and 420.1 cm²/C at 1165 nm. Full article

The widely used plasticizer bisphenol-A (BPA) is well-known for producing neurodegeneration and cognitive disorders, following acute and long-term exposure. Although some of the BPA actions involved in these effects have been unraveled, they are still incompletely known. Basal forebrain cholinergic neurons (BFCN) regulate memory and learning processes and their selective loss, as observed in Alzheimer’s disease and other neurodegenerative diseases, leads to cognitive decline. In order to study the BPA neurotoxic effects on BFCN and the mechanisms through which they are induced, 60-day old Wistar rats were used, and a neuroblastoma cholinergic cell line from the basal forebrain (SN56) was used as a basal forebrain cholinergic neuron model. Acute treatment of rats with BPA (40 µg/kg) induced a more pronounced basal forebrain cholinergic neuronal loss. Exposure to BPA, following 1- or 14-days, produced postsynaptic-density-protein-95 (PSD95), synaptophysin, spinophilin, and N-methyl-D-aspartate-receptor-subunit-1 (NMDAR1) synaptic proteins downregulation, an increase in glutamate content through an increase in glutaminase activity, a downregulation in the vesicular-glutamate-transporter-2 (VGLUT2) and in the WNT/β-Catenin pathway, and cell death in SN56 cells. These toxic effects observed in SN56 cells were mediated by overexpression of histone-deacetylase-2 (HDAC2). These results may help to explain the synaptic plasticity, cognitive dysfunction, and neurodegeneration induced by the plasticizer BPA, which could contribute to their prevention. Full article

Catalytic ozonation for the total mineralization of bisphenol-A (BPA) from aqueous solution was investigated in the presence of various silica-based catalysts such as mesoporous silica, acid-activated bentonite (HMt) and montmorillonite-rich materials (Mt) ion-exchanged with Na⁺ and Fe²⁺ cations (NaMt and Fe(II)Mt). The effects of the catalyst surface were studied by correlating the hydrophilic character and catalyst dispersion in the aqueous media to the silica content and BPA conversion. To the best of our knowledge, this approach has barely been tackled so far. Acid-activated and iron-free clay catalysts produced complete BPA degradation in short ozonation times. The catalytic activity was found to strongly depend on the hydrophilic character, which, in turn, depends on the Si content. Catalyst interactions with water and BPA appear to promote hydrophobic adsorption in high Si catalysts. These findings are of great importance because they allow tailoring silica-containing catalyst properties for specific features of the waters to be treated. Full article

The neuropeptide neurotensin (NTS) is involved in regulating the reproductive axis and is expressed at each level of this axis (hypothalamus–pituitary–gonads). This dependence on estrogen levels has been widely demonstrated in the hypothalamus and pituitary. We focused on confirming the relationship of NTS with estrogens and the gonadal axis, using a particularly important environmental estrogenic molecule, bisphenol-A (BPA). Based on the experimental models or in vitro cell studies, it has been shown that BPA can negatively affect reproductive function. We studied for the first time the action of an exogenous estrogenic substance on the expression of NTS and estrogen receptors in the pituitary-gonadal axis during prolonged in vivo exposure. The exposure to BPA at 0.5 and 2 mg/kg body weight per day during gestation and lactation was monitored through indirect immunohistochemical procedures applied to the pituitary and ovary sections. Our results demonstrate that BPA induces alterations in the reproductive axis of the offspring, mainly after the first postnatal week. The rat pups exposed to BPA exhibited accelerated sexual maturation to puberty. There was no effect on the number of rats born per litter, although the fewer primordial follicles suggest a shorter fertile life. Full article