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4-Borono-L-phenylalanine (BPA) is a key [.sup.10]B carrier used in boron neutron capture therapy (BNCT), while its PET tracer analogue, 4-borono-2-[.sup.18]F-fluoro-L-phenylalanine ([.sup.18]F-BPA), enables non-invasive visualization of tumour boron uptake. Since BNCT efficacy depends on precise tumour boron accumulation, we evaluated whether [.sup.18]F-BPA mirrors BPA's transport and biodistribution. In vitro, BPA exhibited a highly consistent uptake profile with its non-radioactive fluorinated analogue, 2-[.sup.19]F-4-borono-L-phenylalanine ([.sup.19]F-BPA), across nine cancer cell lines (r = 0.9455, P < 0.001) and tri-iodothyronine (T3)-mediated LAT-1 inhibition markedly reduced the uptake of both BPA and [.sup.19]F-BPA. In vivo, BPA and [.sup.18]F-BPA showed predominant accumulation in the kidneys and pancreas in Sprague-Dawley rats, with substantially lower levels detected in other organs. Importantly, in tumour-bearing mice, the time-concentration curve of BPA and the time-activity curve of [.sup.18]F-BPA in tumours were found to be highly consistent, and showed a corresponding relationship between BPA concentration and [.sup.18]F-BPA activity in terms of accumulation in tumour, blood, and muscle (r = 0.9623, P < 0.0001). Collectively, these findings confirm that BPA and [.sup.18]F-BPA not only share LAT-1-mediated transport mechanisms, but also exhibit similar pharmacokinetics and tumour-specific accumulation. This substantiates the use of [.sup.18]F-BPA as a reliable surrogate for visualizing BPA biodistribution and optimizing patient-specific BNCT treatment planning.

Dietary exposure was introduced as the primary way Bisphenol A (BPA) enters the human body. Although significant efforts have been made to analyze BPA's presence in different foodstuffs, less attention has been given to introducing the conditions that facilitate BPA release. This review aimed to mention possible factors affecting BPA release into foods and beverages. According to the results, the critical factors in BPA release are temperature, manufacturing process, food and packaging type, pH, mineral elements, repeated use, irradiation, washing, contact time, and using detergents. It showed that using PC containers, high temperature and pH, storage under solar irradiation, alkaline detergents, water hardness, and repeated use could increase the BPA release from containers into foodstuff. During various conditions, hydrolysis of the carbonate linkage and d‐spacing will increase. Considering these parameters and limiting the use of PC containers, the potential risk of BPA exposure could be eliminated. Repeated use, washing, and rinsing methods with boiling water, type of detergents, alkaline condition, type of food and packaging, manufacturing process, and irradiation could be effective in BPA leaching. It is recommended to substitute the PC with safer packaging, avoid storage of bottled water under solar irradiation and outdoors, and using boiled water in baby bottles. The manufacturer should state the cleaning and sterilization methods and discarding condition of products on the label of bottles or packaging.

This opinion describes the assessment of the risks to public health associated with bisphenol A (BPA) exposure. Exposure was assessed for various groups of the human population in three different ways: (1) external (by diet, drinking water, inhalation, and dermal contact to cosmetics and thermal paper); (2) internal exposure to total BPA (absorbed dose of BPA, sum of conjugated and unconjugated BPA); and (3) aggregated (from diet, dust, cosmetics and thermal paper), expressed as oral human equivalent dose (HED) referring to unconjugated BPA only. The estimated BPA dietary intake was highest in infants and toddlers (up to 0.875 µg/kg bw per day). Women of childbearing age had dietary exposures comparable to men of the same age (up to 0.388 µg/kg bw per day). The highest aggregated exposure of 1.449 µg/kg bw per day was estimated for adolescents. Biomonitoring data were in line with estimated internal exposure to total BPA from all sources. BPA toxicity was evaluated by a weight of evidence approach. “Likely” adverse effects in animals on kidney and mammary gland underwent benchmark dose (BMDL10) response modelling. A BMDL10 of 8 960 µg/kg bw per day was calculated for changes in the mean relative kidney weight in a two generation toxicity study in mice. No BMDL10 could be calculated for mammary gland effects. Using data on toxicokinetics, this BMDL10 was converted to an HED of 609 µg/kg bw per day. The CEF Panel applied a total uncertainty factor of 150 (for inter‐ and intra‐species differences and uncertainty in mammary gland, reproductive, neurobehavioural, immune and metabolic system effects) to establish a temporary Tolerable Daily Intake (t‐TDI) of 4 µg/kg bw per day. By comparing this t‐TDI with the exposure estimates, the CEF Panel concluded that there is no health concern for any age group from dietary exposure and low health concern from aggregated exposure. The CEF Panel noted considerable uncertainty in the exposure estimates for non‐dietary sources, whilst the uncertainty around dietary estimates was relatively low.

Bisphenols are important environmental pollutants that are extensively studied due to different detrimental effects, while the molecular mechanisms behind these effects are less well understood. Like other environmental pollutants, bisphenols are being tested in various experimental models, creating large expression datasets found in open access storage. The meta-analysis of such datasets is, however, very complicated for various reasons. Here, we developed an integrating statistical and machine-learning model approach for the meta-analysis of bisphenol A (BPA) exposure datasets from different mouse tissues. We constructed three joint datasets following three different strategies for dataset integration: in particular, using all common genes from the datasets, uncorrelated, and not co-expressed genes, respectively. By applying machine learning methods to these datasets, we identified genes whose expression was significantly affected in all of the BPA microanalysis data tested; those involved in the regulation of cell survival include: Tnfr2, Hgf-Met, Agtr1a, Bdkrb2; signaling through Mapk8 (Jnk1)); DNA repair (Hgf-Met, Mgmt); apoptosis (Tmbim6, Bcl2, Apaf1); and cellular junctions (F11r, Cldnd1, Ctnd1 and Yes1). Our results highlight the benefit of combining existing datasets for the integrated analysis of a specific topic when individual datasets are limited in size.

In 2015, EFSA established a temporary tolerable daily intake (t‐TDI) for BPA of 4 μg/kg body weight (bw) per day. In 2016, the European Commission mandated EFSA to re‐evaluate the risks to public health from the presence of BPA in foodstuffs and to establish a tolerable daily intake (TDI). For this re‐evaluation, a pre‐established protocol was used that had undergone public consultation. The CEP Panel concluded that it is Unlikely to Very Unlikely that BPA presents a genotoxic hazard through a direct mechanism. Taking into consideration the evidence from animal data and support from human observational studies, the immune system was identified as most sensitive to BPA exposure. An effect on Th17 cells in mice was identified as the critical effect; these cells are pivotal in cellular immune mechanisms and involved in the development of inflammatory conditions, including autoimmunity and lung inflammation. A reference point (RP) of 8.2 ng/kg bw per day, expressed as human equivalent dose, was identified for the critical effect. Uncertainty analysis assessed a probability of 57–73% that the lowest estimated Benchmark Dose (BMD) for other health effects was below the RP based on Th17 cells. In view of this, the CEP Panel judged that an additional uncertainty factor (UF) of 2 was needed for establishing the TDI. Applying an overall UF of 50 to the RP, a TDI of 0.2 ng BPA/kg bw per day was established. Comparison of this TDI with the dietary exposure estimates from the 2015 EFSA opinion showed that both the mean and the 95th percentile dietary exposures in all age groups exceeded the TDI by two to three orders of magnitude. Even considering the uncertainty in the exposure assessment, the exceedance being so large, the CEP Panel concluded that there is a health concern from dietary BPA exposure. This publication is linked to the following EFSA Journal article: http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2023.p210401/full

Bisphenol A (BPA) is a widespread organic micro-pollutant, found in most environments, including alpine and Arctic regions, and several matrices such as waters and aerosols. Polar regions are characterized by periods of intense irradiation with no sunset due to the continuous sunlight, while alpine areas, despite following the day-night cycle of mid-latitudes, also undergo strong irradiation. For such conditions, it is possible that a fraction of the BPA present in snow may degrade through direct photolysis, producing other unknown species with different environmental mobility and possible ecotoxic effects. Furthermore, the snowpack is rich in species (known as photosensitizers) that facilitate indirect photodegradation processes through reactions involving hydroxyl radicals  , singlet oxygen ( O ), excited triplet states of the organic fraction ( CDOM*), and nitrite/nitrate. In this study, we investigated both direct and indirect photodegradation of BPA in the presence of specific photosensitizers producing  , O , CDOM*, and NO to specifically explore the products of the reaction. The study was conducted in both liquid water and ice, under light and dark conditions. Results, obtained by HPLC-HRMS, revealed that the matrix in which the reaction takes place, in addition to the photosensitizer used, may influence the degradation by-products. This allows for the possibility of distinguishing the reaction environment based on the identified product.

Concerns about the effects of bisphenol A (BPA) on human brain and behavior are not novel; however, Grohs and colleagues have contributed groundbreaking data on this topic in a recent issue of Environmental Health . For the first time, associations were reported between prenatal BPA exposure and differences in children’s brain microstructure, which appeared to mediate the association between this exposure and children’s behavioral symptoms. Findings in numerous previous mother-child cohorts have pointed in a similar worrying direction, linking higher BPA exposure during pregnancy to more behavioral problems throughout childhood as assessed by neuropsychological questionnaires. Notwithstanding, this body of work has not been adequately considered in risk assessment. From a toxicological perspective, results are now available from the CLARITY-BPA consortium, designed to reconcile academic and regulatory toxicology findings. In fact, the brain has consistently emerged as one of the most sensitive organs disrupted by BPA, even at doses below those considered safe by regulatory agencies such as the European Food Safety Authority (EFSA). In this Commentary, we contextualize the results of Grohs et al. within the setting of previous epidemiologic and CLARITY-BPA data and express our disquiet about the “all-or-nothing” criterion adopted to select human data in a recent EFSA report on the appraisal methodology for their upcoming BPA risk assessment. We discuss the most relevant human studies, identify emerging patterns, and highlight the need for adequate assessment and interpretation of the increasing epidemiologic literature in this field in order to support decision-making. With the aim of avoiding a myopic or biased selection of a few studies in traditional risk assessment procedures, we propose a future reevaluation of BPA focused on neurotoxicity and based on a systematic and comprehensive integration of available mechanistic, animal, and human data. Taken together, the experimental and epidemiologic evidence converge in the same direction: BPA is a probable developmental neurotoxicant at low doses. Accordingly, the precautionary principle should be followed, progressively implementing stringent preventive policies worldwide, including the banning of BPA in food contact materials and thermal receipts, with a focus on the utilization of safer substitutes.

Boron neutron capture therapy (BNCT) is a binary targeted radiotherapy that uses boron agents to treat refractory malignancies. This study developed a novel boronophenylalanine (BPA)-loaded liposome doped with o-carborane (CB) for BNCT. We applied response surface methodology (RSM) to identify factors affecting BPA loading and optimized encapsulation efficiency (EE) to minimize BPA loss. In in vitro experiments, these liposomes demonstrated promising characteristics for BNCT. The nanoparticle properties of CB-BPA-Lips remain stable for at least 48 h, and CB-BPA-Lips can effectively reduce the release of the agents loaded within them. Both cell viability assays and apoptosis assays have shown that CB-BPA-Lips have good biocompatibility and a lower inhibitory effect on cell viability than BPA. Cellular boron uptake peaked at 47.3642 ng B/10 cells in A549 lung cancer cells and peaked at 38.8875 ng B/10 cells in Bronchial Epithelium transformed with Ad12-SV40 2B (BEAS-2B) human normal bronchial epithelial cells at 24 h post-treatment, with both exceeding uptake in the BPA control group. Overall, this work presents an optimized liposomal formulation that enhances boron delivery to cancer cells and provides a potential candidate boron agent for BNCT pending in-depth in vivo studies.

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.

Bisphenol A (BPA), an endocrine-disrupting chemical, is used to produce a wide variety of plastic and common house-hold items. Therefore, there is potential continual exposure to this compound. BPA exposure has been linked to certain placenta-associated obstetric complications such as preeclampsia, fetal growth restriction, miscarriage, and preterm birth. However, how BPA exposure results in these disorders remains uncertain. Hence, we have herein summarized the reported impacts of BPA on the morphology and metabolic state of the placenta and have proposed mechanisms by which BPA affects placentation, potentially leading to obstetric complications. Current findings suggest that BPA induces pathological changes in the placenta and disrupts its metabolic activities. Based on exposure concentrations, BPA can elicit apoptotic or anti-apoptotic signals in the trophoblasts, and can exaggerate trophoblast fusion while inhibiting trophoblast migration and invasion to affect pregnancy. Accordingly, the usage of BPA products by pregnant women should be minimized and less harmful alternative chemicals should be explored and employed where possible. Summary Sentence This review provides insight into the mechanisms by which bisphenol A, an endocrine-disrupting chemical that is used in plastic found in common household items, affects placental development, potentially leading to pregnancy complications. Graphical Abstract