A fast method for bisphenol A and six analogues (S, F, Z, P, AF, AP) determination in urine samples based on dispersive liquid-liquid microextraction and liquid chromatography-tandem mass spectrometry

Cortisol and cortisone determination by disposable pipette extraction (DPX) and ultra-efficient liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) in urine and saliva samples from patients with Parkinson's disease

Higher serum cortisol levels appear to be associated with stress that can overlap or manifest anxiety, fatigue, depression, and sleep dysfunction. These are common and intrusive non-motor symptoms of Parkinson's disease (PD). Thus, stress has been proposed to mediate Parkinson's disease development, and cortisol has been suggested as a biomarker for the generation of stress-related symptoms in Parkinson's disease. This study describes sensitive and robust disposable pipette extraction (DPX) and ultra-efficient liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method to determine cortisol and cortisone (as potential endocrine biomarkers for Parkinson's disease) in 24-h urine and saliva samples obtained from Parkinson's disease patients. Important parameters on DPX extraction were optimized to achieve the best extraction recovery and cleanup efficiency. The proposed method was linear from 0.5 (lower limit of quantification) to 500 ng mL-1 for cortisol and from 3.0 (lower limit of quantification) to 500 ng mL-1 for cortisone. To determine whether urinary cortisol and urinary cortisone are adequate as biomarkers to evaluate the level of anxiety in patients suffering from Parkinson's disease, twenty-nine Parkinson's disease patients (18 with anxiety and 11 without anxiety) were selected for urine analysis. Based on the obtained results, 24-h urine samples obtained from Parkinson's disease patients with anxiety had higher cortisone levels than samples obtained from healthy controls. Receiving operating curves (ROC) analysis, which presented the area under the ROC curve (AUC = 0.733), showed that urinary cortisone levels (µg/24-h urine) were sensitive (56.3%) and specific (93.3%) for distinguishing Parkinson's disease patients with anxiety from healthy controls. In terms of salivary results, PD patients' samples taken 30 min after waking up had higher cortisol and cortisone levels than healthy controls, while their samples taken at night had lower cortisol and cortisone levels.

Developmental exposures to common environmental pollutants result in long-term Reprogramming of hypothalamic-pituitary axis in mice

Humans are exposed to a range of endocrine disrupting chemicals (EDCs). Many studies demonstrate that exposures to EDCs during critical windows of development can permanently affect endocrine health outcomes. Most experimental studies address changes in secretion of hormones produced by gonads, thyroid gland and adrenals, and little is known about the ability of EDCs to produce long-term changes in the hypothalamic-pituitary (HP) control axes. Here, we examined the long-term effects of three common EDCs on male mouse HP gene expression, following developmental exposures. Pregnant mice were exposed to 0.2 mg/ml solutions of bisphenol S (BPS), 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), or 3,3',5,5'-tetrabromobisphenol A (TBBPA) from pregnancy day 8 through lactation day 21 (weaning day). Male offspring were left untreated until postnatal day 140, where pituitaries and hypothalami were collected. Pituitaries were assed for gene expression via RNA sequencing, while specific genes were assessed for expression in hypothalami via RT-qPCR. Differential expression, as well as gene enrichment and pathway analysis, indicated that all three chemicals induced long-term changes, (mostly suppression) in pituitary genes involved in its endocrine function. BPS and BDE-47 produced effects overlapping significantly at the level of effected genes and pathways. All three chemicals altered pathways of gonad and liver HP axes, while BPS altered HP-adrenal and BDE-47 altered HP-thyroid pathways specifically. All three chemicals reduced expression of immune genes in the pituitaries. Targeted gene expression in the hypothalamus indicates down regulation of hypothalamic endocrine control genes by BPS and BDE-47 groups, concordant with changes in the pituitary, suggesting that these chemicals suppress overall HP endocrine function. Interestingly, all three chemicals altered pituitary genes of GPCR-mediated intracellular signaling molecules, key signalers common to many pituitary responses to hormones. The results of this study show that developmental exposures to common EDCs have long-term impacts on hormonal feedback control at the hypothalamic-pituitary level.

Development and application of bisphenol S electrochemical immunosensor and iridium oxide nanoparticle-based lateral flow immunoassay

Bisphenol S (BPS) is a common pollutant in the environment and has posed a potential threat to aquatic animals and human health. To accurately assess the pollution level and ecological risk of BPS, there is an urgent need to establish simple and sensitive detection methods for BPS. In this study, BPS complete antigen was successfully prepared by introducing methyl 4-bromobutyrate and coupling bovine serum albumin (BSA). The monoclonal antibody against BPS (anti-BPS mAb) with high affinity (1: 256,000) was developed based on the BPS complete antigen, which showed low cross-reactivity with BPS structural analogues. Then, an electrochemical immunosensor was constructed to detect BPS using multi-walled carbon nanotubes and gold nanoflower composites as signal amplification elements and using anti-BPS mAb as the probe. The electrochemical immunosensor had a linear range from 1 to 250 ng⋅mL-1 and a limit of detection (LOD) down to 0.6 ng⋅mL-1. Additionally, a more stable and sensitive lateral flow immunoassay (LFIA) for BPS was developed based on iridium oxide nanoparticles, with a visual detection limit of 1 ng⋅mL-1, which was 10 times lower than that of classical Au-NPs LFIA. After evaluation of their stability and specificity, the reliability of these two methods were further validated by measuring BPS concentrations in the water and fish tissues. Thus, this study provides sensitive, robust and rapid methods for the detection of BPS in the environment and organisms, which can provide a methodological reference for monitoring environmental contaminants.

Sample preparation for suspect screening of persistent, mobile and toxic substances and their phase II metabolites in human urine by mixed-mode liquid chromatography

Persistent, mobile and toxic substances have drawn attention nowadays due to their particular properties, but they are overlooked in human monitorization works, limiting the knowledge of the human exposome. In that sense, human urine is an interesting matrix since not only parent compounds are eliminated, but also their phase II metabolites that could act as biomarkers. In this work, 11 sample preparation procedures involving preconcentration were tested to ensure maximum analytical coverage in human urine using mixed-mode liquid chromatography coupled with high-resolution tandem mass spectrometry. The optimized procedure consisted of a combination of solid-phase extraction and salt-assisted liquid-liquid extraction and it was employed for suspect screening. Additionally, a non-discriminatory dilute-and-shoot approach was also evaluated. After evaluating the workflow in terms of limits of identification and type II errors (i.e., false negatives), a pooled urine sample was analysed. From a list of 1450 suspects and in-silico simulated 1568 phase II metabolites (i.e. sulphates, glucuronides, and glycines), 44 and 14 substances were annotated, respectively. Most of the screened suspects were diverse industrial chemicals, but biocides, natural products and pharmaceuticals were also detected. Lastly, the complementarity of the sample preparation procedures, columns, and analysis conditions was assessed. As a result, dilute-and-shoot and the Acclaim Trinity P1 column at pH = 3 (positive ionization) and pH = 7 (negative ionization) allowed the maximum coverage since almost 70 % of the total suspects could be screened using those conditions.

Levels of organic pollutants and metals/metalloids in infant formula marketed in Brazil: Risks to early-life health

Infant formula intake is recommended to ensure comprehensive nutritional and caloric fulfillment when exclusive breastfeeding is not possible. However, similarly to breast milk, infant formulas may also contain pollutants capable of inducing endocrine-disrupting and neurotoxic effects. Thus, considering the sensitivity of their developing physiological systems and that infants have heightened susceptibility to environmental influences, this study was aimed at assessing the contents of essential elements, and inorganic and organic pollutants in infant formulas marketed in Brazil. Additionally, health risk assessments for selected contaminants were also performed. Measured contents of essential elements (Ca, Fe, Mg, Mn, Cu, Se, and Zn) were congruent with label information. Nevertheless, some toxic elements (Pb, Cd, As, Ni, and Al) were also detected. Notably, in the upper-bound scenario, Pb and Cd surpassed established threshold values when comparing the estimated daily intake (EDI) and tolerable daily intake (TDI - 3.57 and 0.36 μg/kg bw, respectively). Bisphenol P (BPP) and benzyl butyl phthalate (BBP) were frequently detected (84 % detection rate both) with elevated contents (BPP median = 4.28 ng/g and BBP median = 0.24 ng/g). Furthermore, a positive correlation (0.41) was observed between BPP and BBP, implying a potential co-occurrence within packaging materials. Methyl-paraben also correlated positively with BBP (0.57), showing a detection rate of 53 %. The cumulative PBDE contents ranged from 0.33 to 1.62 ng/g, with BDE-154 and BDE-47 the dominant congeners. When comparing EDI values with TDIs, all organic pollutants remained below the thresholds across all exposure scenarios. Moreover, non-carcinogenic risks were below the threshold (HQ > 1) when dividing the EDIs by the respective reference doses for chronic exposure. While the current findings may suggest that infant formula intake poses no immediate risk in terms of the evaluated chemicals, it remains imperative to conduct further research to safeguard the health of infants considering other chemicals, as well as their potential cumulative effects.

Comprehensive analysis of bisphenol analogues in complex water using a group-targeting aptamer engineered by base mutation

Bisphenol analogues (BPs) are typical environmental hormones with endocrine-disrupting effects and reproductive toxicity requiring analysis and monitoring in complex aquatic environments. However, the presence of various co-existing contaminants makes the accurate determination of total BPs difficult. To address this challenge, there is a strong need to obtain a group-targeting binder to specifically detect a class of BPs. In this work, for the first time we have identified the group-targeting BPs-aptamer with similar affinities for multiple structurally and qualitatively similar BPs. Base mutations were introduced into an aptamer specific to bisphenol A (BPA) and utilized molecular docking calculations to identify a group-targeting aptamer capable of binding BPs, including BPA, bisphenol B (BPB), bisphenol E (BPE) and bisphenol F (BPF) with binding constants in the range of 2.0 × 106 ∼ 2.7 × 106 / M. In addition, an electrochemical aptamer-based sensor (aptasensor) was constructed for highly sensitive and comprehensive analysis of a class of BPs. This aptasensor demonstrated remarkable anti-interference performance against co-existing contaminants at concentrations up to 100-fold and achieved an impressive detection limit of 6.7 pM. This innovative approach of engineering a group-targeting BPs-aptamer is important for the comprehensive analysis of BPs, providing insights into identification and monitoring a class of pollutants.

The role of sample preparation in suspect and non-target screening for exposome analysis using human urine

The use of suspect and non-target screening (SNTS) for the characterization of the chemical exposome employing human biofluids is gaining attention. Among the biofluids, urine is one of the preferred matrices since organic xenobiotics are excreted through it after metabolization. However, achieving a consensus between selectivity (i.e. preserving as many compounds as possible) and sensitivity (i.e. minimizing matrix effects by removing interferences) at the sample preparation step is challenging. Within this context, several sample preparation approaches, including solid-phase extraction (SPE), liquid-liquid extraction (LLE), salt-assisted LLE (SALLE) and dilute-and-shoot (DS) were tested to screen not only exogenous compounds in human urine but also their phase II metabolites using liquid-chromatography coupled to high-resolution tandem mass spectrometry (LC-HRMS/MS). Additionally, enzymatic hydrolysis of phase II metabolites was evaluated. Under optimal conditions, SPE resulted in the best sample preparation approach in terms of the number of detected xenobiotics and metabolites since 97.1% of the total annotated suspects were present in samples extracted by SPE. In LLE and SALLE, pure ethyl acetate turned out to be the best extractant but fewer suspects than with SPE (80.7%) were screened. Lastly, only 52.5% of the suspects were annotated in the DS approach, showing that it could only be used to detect compounds at high concentration levels. Using pure standards, the presence of diverse xenobiotics such as parabens, industrial chemicals (benzophenone-3, caprolactam and mono-2-ethyl-5-hydroxyhexyl phthalate) and chemicals related to daily habits (caffeine, cotinine or triclosan) was confirmed. Regarding enzymatic hydrolysis, only 10 parent compounds of the 44 glucuronides were successfully annotated in the hydrolysed samples. Therefore, the screening of metabolites in non-hydrolysed samples through SNTS is the most suitable approach for exposome characterization.

A protocol based on solid phase microextraction -gas chromatography-tandem mass spectrometry for the monitoring of parabens and bisphenols in human saliva

The herein presented work aims to the development of an easy method for the quantitative determination of parabens and bisphenols in human salivabased on the use of methyl chloroformate as a derivatizing agent, followed by solid-phase microextraction (SPME) and gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS) analysis with selected reaction monitoring (SRM). Using multivariate analysis, two derivatization strategies were compared and optimized, demonstrating that the use of methyl chloroformate led to better sensitivity than the classical derivatization by acetic anhydride. Good performance in the sorption process of the derivatized target analytes was obtained using the most recent commercialized overcoated fiber (PDMS/DVB/PDMS). The validation procedure of the final protocol led to satisfactory results in terms of linearity, limit of quantitation, accuracy, and precision. All parabens were quantified from 10 ng/L using the developed method, except for methylparaben, which was quantified from 100 ng/L along with all bisphenols. Intra- and inter-day accuracy and intra- and inter-day precision can be considered satisfactory for all analytes (values between 73% and 118%), except for the inter-day accuracy of BPF. Quite good results also in terms of matrix effect were obtained for the target compounds (range 71% to 118%, RSD% less than 13.6%), except for BPA at the middle concentration and MeP at the lowest concentration. The greenness of the method was evaluated and the results indicated that our approach is more eco-friendly than previously published methods. Based on its characteristics, the presented method can be considered a suitable approach to determine parabens and bisphenols in routine analysis for biomonitoring purposes.

Dilute-and-shoot coupled to mixed mode liquid chromatography-tandem mass spectrometry for the analysis of persistent and mobile organic compounds in human urine

In this work, a comprehensive method for the simultaneous determination of 33 diverse persistent and mobile organic compounds (PMOCs) in human urine was developed by dilute-and-shoot (DS) followed by mixed-mode liquid chromatography coupled with tandem mass spectrometry (MMLC-MS/MS). In the sample preparation step, DS was chosen since it allowed the quantification of all targets in comparison to lyophilization. For the chromatographic separation, Acclaim Trinity P1 and P2 trimodal columns provided greater capacity for retaining PMOCs than reverse phase and hydrophilic interaction liquid chromatography. Therefore, DS was validated at 5 and 50 ng/mL in urine with both mixed mode columns at pH = 3 and 7. Regarding figures of merit, linear calibration curves (r2 > 0.999) built between instrumental quantification limits (mostly below 5 ng/mL) and 500 ng/mL were achieved. Despite only 60% of the targets were recovered at 5 ng/mL because of the dilution, all PMOCs were quantified at 50 ng/mL. Using surrogate correction, apparent recoveries in the 70-130% range were obtained for 91% of the targets. To analyse human urine samples, the Acclaim Trinity P1 column at pH = 3 and 7 was selected as a consensus between analytical coverage (i.e. 94% of the targets) and chromatographic runs. In a pooled urine sample, industrial chemicals (acrylamide and bisphenol S), biocides and their metabolites (2-methyl-4-isothiazolin-3-one, dimethyl phosphate, 6-chloropyridine-3-carboxylic acid, and ammonium glufosinate) and an artificial sweetener (aspartame) were determined at ng/mL levels. The outcomes of this work showed that humans are also exposed to PMOCs due to their persistence and mobility, and therefore, further human risk assessment is needed.

MOF-derived CeO2/Co3O4-Fe2O3@CC nanocomposites as highly sensitive electrochemical sensor for bisphenol a detection

A novel CeO₂/Co₃O₄-Fe₂O₃@CC electrode derived from CeCo-MOFs was developed for detecting the endocrine disruptor bisphenol A (BPA). Firstly, bimetallic CeCo-MOFs were prepared by hydrothermal method, and obtained material was calcined to form metal oxides after doping Fe element. The results suggested that hydrophilic carbon cloth (CC) modified with CeO₂/Co₃O₄-Fe₂O₃ had good conductivity and high electrocatalytic activity. By the analyses of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), the introduction of Fe increased the current response and conductivity of the sensor, greatly increasing the effective active area of the electrode. Significantly, electrochemical test proves that the prepared CeO₂/Co₃O₄-Fe₂O₃@CC had excellent electrochemical response to BPA with a low detection limit of 8.7 nM, an excellent sensitivity of 20.489 μA/μM·cm², a linear range of 0.5-30 μM, and strong selectivity. In addition, the CeO₂/Co₃O₄-Fe₂O₃@CC sensor had a high recovery rate for the detection of BPA in real tap water, lake water, soil eluent, seawater, and PET bottle samples, which showed its potential in practical applications. To sum up, the CeO₂/Co₃O₄-Fe₂O₃@CC sensor prepared in this work had excellent sensing performance, good stability and selectivity for BPA, which can be well used for the detection of BPA.

Challenges in the Analytical Preparation of a Biological Matrix in Analyses of Endocrine-Disrupting Bisphenols

Endocrine-disrupting chemicals (EDCs) are xenobiotics presented in a variety of everyday products that may disrupt the normal activity of hormones. Exposure to bisphenol A as EDC at trace and ultra-trace levels is associated with adverse health effects, and children are recognized as the most vulnerable group to EDCs exposure. In this review, a summary is presented of up-to-date sample preparation methods and instrumental techniques applied for the detection and quantification of bisphenol A and its structural analogues in various biological matrices. Biological matrices such as blood, cell-free blood products, urine, saliva, breast milk, cordial blood, amniotic and semen fluids, as well as sweat and hair, are very complex; therefore, the detection and later quantification of bisphenols at low levels present a real analytical challenge. The most popular analytical approaches include gas and liquid chromatography coupled with mass spectrometry, and their enhanced reliability and sensitivity finally allow the separation and detection of bisphenols in biological samples, even as ultra-traces. Liquid/liquid extraction (LLE) and solid-phase extraction (SPE) are still the most common methods for their extraction from biological matrices. However, many modern and environmentally safe microextraction techniques are currently under development. The complexity of biological matrices and low concentrations of analytes are the main issues for the limited identification, as well as understanding the adverse health effects caused by chronical and ubiquitous exposure to bisphenols and its analogues.

A Fast Method for Determination of Seven Bisphenols in Human Breast Milk Samples with the Use of HPLC-FLD

Plastic pollution, where bisphenol A (BPA) is widely used in its production, has gained popularity. BPA omnipresence and toxicity, especially for infants, has led food safety authorities to place restrictions on BPA usage. It has led to the introduction of the marked 'BPA-free'-labelled products, where BPA is often replaced by other bisphenols (BPs) which are suspected of being similar or even more toxic than BPA. Moreover, the free forms of BPs are more dangerous than their conjugated forms and the conjugation of BPs is less effective in infants than in adults. Considering that human breast milk is the main source of nutrition for infants, the constant biomonitoring not only of BPA, but the wider group of BPs in such crucial matrices seems to be vital. In this study, a fast, simple, 'green' and cost-effective DLLME-based extraction technique combined with HPLC-FLD was optimized for the determination of seven selected bisphenols simultaneously. The procedure has satisfactory recovery values of 67-110% with the most RSD% at 17%. The LODs and LOQs ranged from 0.5 ng/mL to 2.1 ng/mL and 1.4 ng/mL to 6.3 ng/mL, respectively. The procedure was successfully applied to the biomonitoring of free forms of BPs in 10 real human breast milk samples.

Detection of bisphenols in Indian surface water, tap water, and packaged drinking water using dispersive liquid-liquid microextraction: exposure assessment for health risk

The prevalence of bisphenols (BPs) has been well documented in the aquatic environment of many countries, but such studies from India are quite limited. The present work aimed to determine the occurrence of BPs in surface water (n = 96), tap water (n = 172), and packaged drinking water (n = 42) and estimate their exposure to humans. For this, a simple, sensitive, cost-effective, and green analytical chemistry method based on dispersive liquid-liquid microextraction (DLLME) was employed. Bisphenol A (BPA) was found as the most prevalent bisphenol (mean concentration range = 980-6470 ng/L) in all the water samples, with a % detection frequency of 17-39%. Bisphenol S (BPS) and bisphenol Z (BPZ) were also detected in all types of water samples. The mean estimated daily intake (EDI) for total BPs (tap water and packaged drinking water) was found to be 474.37 ng/kg b.w./day in adults and 665.65 ng/kg b.w./day in children, respectively. This indicated that the total exposure to all the detected BPs obtained for adults and children was lower than the temporary tolerable daily intake (t-TDI) recommended by the European Food Safety Authority (EFSA) (4 μg/kg b.w./day), thereby posing no substantial risks to humans from consuming water from the tap and/or packaged drinking water.

Aptamer-functionalised metal-organic frameworks as an 'on-off-on' fluorescent sensor for bisphenol S detection

Bisphenol S (BPS) is an industrial chemical that is widely used to manufacture daily items, such as plastic water bottles, milk bottles, water cups, and paper products. BPS is a biologically toxic environmental endocrine disruptor. Long-term exposure to BPS can disrupt the reproductive system, endanger health, and increase the risk of cancer. The metal-organic framework UiO-66 is characterised with high thermal and chemical stability, a simple synthetic route, and low preparation cost. In this study, we modified UiO-66 with nucleic acid aptamers to prepare an 'on-off-on' fluorescent sensor for the simple and rapid detection of BPS. The FAM-labelled aptamer was selected as the fluorescent probe (i.e. 'on'). In the presence of UiO-66, the FAM-labelled aptamer adsorbed onto the surface of the UiO-66 material, and the fluorescence of FAM was quenched by photoinduced electron transfer (i.e. 'off'). When BPS was introduced into the system, the configuration of the FAM-labelled aptamer changed after binding to BPS, and the adsorption of FAM on UiO-66 weakened, resulting in fluorescence recovery (i.e. 'on'). Based on this principle, the reaction system was optimised, and the BPS content was analysed according to the change in the fluorescence signal. The signals changed linearly in the BPS concentration range of 2.0 × 10^-4-4.0 × 10^-2 mmol L^-1, and the system had a detection limit of 1.84 × 10^-4 mmol L^-1. The sensor was successfully used to detect the BPS content in commercial plastic bottled water.

Contribution of Reliable Chromatographic Data in QSAR for Modelling Bisphenol Transport across the Human Placenta Barrier

Regulatory measures and public concerns regarding bisphenol A (BPA) have led to its replacement by structural analogues, such as BPAF, BPAP, BPB, BPF, BPP, BPS, and BPZ. However, these alternatives are under surveillance for potential endocrine disruption, particularly during the critical period of fetal development. Despite their structural analogies, these BPs differ greatly in their placental transport efficiency. For predicting the fetal exposure of this important class of emerging contaminants, quantitative structure-activity relationship (QSAR) studies were developed to model and predict the placental clearance indices (CI). The most usual input parameters were molecular descriptors obtained by modelling, but for bisphenols (BPs) with structural similarities or heteroatoms such as sulfur, these descriptors do not contrast greatly. This study evaluated and compared the capacity of QSAR models based either on molecular or chromatographic descriptors or a combination of both to predict the placental passage of BPs. These chromatographic descriptors include both the retention mechanism and the peak shape on columns that reflect specific molecular interactions between solute and stationary and mobile phases and are characteristic of the molecular structure of BPs. The chromatographic peak shape such as the asymmetry and tailing factors had more influence on predicting the placental passage than the usual retention parameters. Furthermore, the QSAR model, having the best prediction capacity, was obtained with the chromatographic descriptors alone and met the criteria of internal and cross validation. These QSAR models are crucial for predicting the fetal exposure of this important class of emerging contaminants.

Application of High-Performance Liquid Chromatography Combined with Fluorescence Detector and Dispersive Liquid-Liquid Microextraction to Quantification of Selected Bisphenols in Human Amniotic Fluid Samples

Bisphenol A (BPA) is a widely produced chemical worldwide found in numerous everyday products. Its endocrine-disrupting properties and omnipresence have aroused concern and led to several restrictions on its use. These restrictions and growing public awareness about the toxicity of BPA have resulted in market products labeled "BPA-free", with BPAs often being replaced by other bisphenols. This is why constant biomonitoring of bisphenol levels in various body fluids and tissues is essential. In this study, we propose the use of simple, cost-effective high-performance liquid chromatography coupled with the fluorescence detector (HPLC-FLD) method for the determination of simultaneously selected bisphenols in amniotic fluid. For the sample preparation, a fast, simple, and "green" dispersive liquid-liquid microextraction (DLLME) method was used, achieving mean recovery values in the range of 80.9-115.9% with relative standard deviations below 12% for all analytes. Limits of quantification (LOQs) determined in the amniotic fluid matrix ranged from 6.17 to 22.72 ng/mL and were obtained from a calibration curve constructed using least-squares linear regression analysis for all cases. The presented sample preparation procedure can be easily adopted for LC-MS analysis.

Long-term exposure to bisphenol A and its analogues alters the behavior of marine medaka (Oryzias melastigma) and causes hepatic injury

Bisphenols (BPA, BPF, and BPAF) are widely present in the aquatic environment and have various adverse effects on aquatic organisms. However, their hepatic toxicity in marine fish is not fully understood. Hence, we examined the growth parameters, histological features, antioxidant defense mechanisms, and gene expression profiles in the livers of marine medaka after exposure to single and combined bisphenols for 70 days. The final body weight and final body length of males exposed to BPAF were significantly higher than those in the control group, and the survival rate was significantly lower. Bisphenol exposure led to vacuolization and local lesions in the liver, especially in the BPAF group, and altered antioxidant enzyme activity in the liver, leading to oxidative stress. In addition, after bisphenol exposure, marine medaka showed anxiolytic effects and a significant reduction in swimming distance compared with that in the control group. As determined by RNA-seq, bisphenol exposure altered multiple biological pathways in the liver, such as fatty acid biosynthesis, fatty acid metabolism, and ribosome biogenesis pathways, with significant changes in gene expression levels. In particular, chgs and vtgs were significantly up-regulated after BPAF exposure, suggesting an estrogenic effect. Overall, bisphenols can adversely affect the growth and metabolism of marine medaka. BPF and BPAF may not be ideal substitutes for BPA.

From target analysis to suspect and non-target screening of endocrine-disrupting compounds in human urine

In the present work, a target analysis method for simultaneously determining 24 diverse endocrine-disrupting compounds (EDCs) in urine (benzophenones, bisphenols, parabens, phthalates and antibacterials) was developed. The target analysis approach (including enzymatic hydrolysis, clean-up by solid-phase extraction and analysis by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS)) was optimized, validated and applied to volunteers’ samples, in which 67% of the target EDCs were quantified. For instance, benzophenone-3 (0.2–13 ng g⁻¹), bisphenol A (7.7–13.7 ng g⁻¹), methyl 3,5-dihydroxybenzoate (8–254 ng g⁻¹), mono butyl phthalate (2–17 ng g⁻¹) and triclosan (0.3–9 ng g⁻¹) were found at the highest concentrations, but the presence of other analogues was detected as well. The developed target method was further extended to suspect and non-target screening (SNTS) by means of LC coupled to high-resolution MS/MS. First, well-defined workflows for SNTS were validated by applying the previously developed method to an extended list of compounds (83), and then, to the same real urine samples. From a list of approximately 4000 suspects, 33 were annotated at levels from 1 to 3, with food additives/ingredients and personal care products being the most abundant ones. In the non-target approach, the search was limited to molecules containing S, Cl and/or Br atoms, annotating 4 pharmaceuticals. The results from this study showed that the combination of the lower limits of detection of MS/MS and the identification power of high-resolution MS/MS is still compulsory for a more accurate definition of human exposome in urine samples.

Urinary levels of monohydroxylated polycyclic aromatic hydrocarbons in Brazilian children and health risk assessment: a human biomonitoring-based study

Monitoring human exposure to polycyclic aromatic hydrocarbons (PAHs) is a public health concern. Children are a vulnerable subgroup of the population with limited human biomonitoring data worldwide. Thus, this study aimed to measure the levels of seven PAH metabolites in urine from Brazilian children and provide risk assessment values for this exposure. Our data show naphthalene was the major contributor to children's exposure to PAHs, with a 100% detection rate. Children in urban regions presented higher exposure to PAHs, with higher concentrations of 2-naphthol in the southeast (1.09 ng/mL, p < 0.05). Furthermore, the highest concentration of 2-naphthol was found in older children (p = 0.02), suggesting a possible difference in dietary habits. Exposure to the carbaryl insecticide is suggested based on the high concentrations of 1-naphthol (1.29 ng/mL) and considering the ratio 1-naphthol/2-naphthol (1.78). Moreover, the positive correlation between the metabolites of fluorine and pyrene also suggests exposure to PAHs by petrol combustion. The risk assessment of the PAH exposure was evaluated using the estimated daily intake (EDI) for two naphthalene metabolites in the study with a 100% detection rate. The EDI was 14.47 ng/kg BW/day. The risk assessment to the PAH exposure revealed a non-carcinogenic risk profile, with a hazard quotient of 0.71. To the best of our knowledge, this study is the first to provide levels of PAHs in Brazilian children.

Simple preparation of surface molecularly imprinted polymer based on silica particles for trace level assay of bisphenol F

A new electrochemical sensor based on molecularly imprinted tetraethyl orthosilicate (TEOS)-based porous interface was developed for selective recognition of bisphenol F (BPF) in this study. The sensor was prepared by depositing the solution containing TEOS and L-tryptophan (L-Trp) in the presence of cetyltrimethylammonium bromide (CTAB) as a pore-maker via hydrolysis/condensation reaction on the glassy carbon electrode (GCE). While the surface morphology and structure characterization were carried out using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), electrochemical characterization was performed through electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The resulted MIP(TEOS:L-Trp)@GCE achieved a wide linear range of 1 × 10^-15-1 × 10^-14 M for BPF detection with an excellent detection limit of 0.291 fM. Furthermore, the recovery of BPF from spiked bottled water and serum samples varied between 98.83 and 101.03%. These results demonstrate that MIP(TEOS:L-Trp)@GCE was found to be a simple, sensitive, and selective smart interface to detect trace pollution even from complicated samples.

Multiclass determination of endocrine disruptors in urine by hollow fiber microporous membrane and liquid chromatography

A simple and rapid methodology was developed using hollow fiber membrane microporous and a 96-well plate system for a high throughput multiclass determination of endocrine disruptors in human urine (diclofenac, diazepam, carbamazepine, ibuprofen, naproxen, carbofuran, methyl parathion, 17-α-ethynyl estradiol, bisphenol A and benzophenone). The quantification and detection of the chemicals were carried out by an HPLC-diode array detector. The fixed conditions for carrying out the method optimization were 1.5 mL of sample and 300 μL of solvent desorption. Multivariate and univariate models were applied to optimize the parameters of the method, achieving the following conditions: 20% diluted urine, 1-octanol of extraction solvent impregnated in the microporous membrane, 70 min extraction in pH 3.0 and 30 min with a mixture of 75% methanol and 25% acetonitrile (v/v) for the desorption. The R² were ≤ 0.9973 for ibuprofen. The LOD ranged from 3.3 to 16.7 ng mL^-1 and the LOQ from 10 to 50 ng mL^-1. Relative recoveries ranged from 71% to 126%. The repeatability (n = 3) ranged from 0.22% to 12.01%, and the intermediate precision (n = 9) ranged from 0.13% to 17.76%. The method presents a good alternative for the determination of different classes of compounds in human urine.

New bisphenol A and bisphenol S analogs: Evaluation of their hERα agonistic and antagonistic activities using the OECD 455 in-vitro assay and molecular modeling

Bisphenol A (BPA) and bisphenol S (BPS) are agonists of hERα receptors and due to BPA regulations in many countries, several substitutes that are close analogs to BPA and BPS were developed. In the presented study, we have determined human estrogen receptor (hER)α agonist and antagonist activities with the validated OECD assay with the hERα-Hela9903 cell line for five different chemical classes of BPA and BPS analogs. This study also defined clear structure-activity relationships for agonist and antagonist activities of the 12 bisphenols on hERα, which are supported by molecular docking studies. These data show that classical analogs of BPA (e.g., bisphenols B, C, AP, E) have comparable or superior estrogenic agonist potencies compared to BPA and BPS. The most potent of these hERα agonists were even more potent than BPA, as bisphenol B and C, with IC50 values of 0.31 μM and 0.48 μM, respectively. Among these selected bisphenols, 4-4'-methylenebis (oxyethylenethio)diphenol was the most potent hERα antagonist, with an IC50 of 0.39 μM. The estrogenic agonist and antagonist potencies of these different chemical classes of BPA and BPS analogs are mutually comparable and can be used as a basis for further structure-activity relationships studies and human risk assessment.

Recent advances in analysis of bisphenols and their derivatives in biological matrices

Biomonitoring is a very useful tool to evaluate human exposure to endocrine-disrupting compounds (EDCs), like bisphenols (BPs), which are widely used in the manufacture of plastics. The development of reliable analytical methods is key in the field of public health surveillance to obtain biomonitoring data to determine what BPs are reaching people's bodies. This review discusses recent methods for the quantitative measurement of bisphenols and their derivatives in biological samples like urine, blood, breast milk, saliva, and hair, among others. We also discuss the different procedures commonly used for sample treatment, which includes extraction and clean-up, and instrumental techniques currently used to determine these compounds. Sample preparation techniques continue to play an important role in the analysis of complex matrices, for liquid matrices the most commonly employed is solid-phase extraction, although microextraction techniques are gaining importance in this field, and for solid samples ultrasound-assisted extraction. The main instrumental techniques used are liquid and gas chromatography coupled with mass spectrometry. Finally, we present data on the main parameters obtained in the validation of the revised methods. This review focuses on various methods developed and applied for trace analysis of bisphenols, their conjugates, halogenated derivatives, and diglycidyl ethers in biological samples to enable the required selectivity and sensitivity. For this purpose, a review is carried out of the most recent relevant publications from 2016 up to present.

A fast and direct determination of bisphenol S in thermal paper samples using paper spray ionization mass spectrometry

Concerns about human health regarding the large use of bisphenol A in thermal papers have led to its replacement by bisphenol S. Analyses of bisphenols require several sample pretreatment steps, which are laborious, expensive, and time-consuming. A paper spray ionization mass spectrometry (PSI-MS) was developed to detect and quantify bisphenol S in three different brands of thermal papers commercially available. Parameters such as paper size, and paper position relative to the mass spectrometer inlet were evaluated. The analyses were performed in selected ion monitoring mode on a linear ion trap mass spectrometer. The developed method presented absolute recovery values ranging from 92.2 to 109.04%, accuracy values from -1.2 to 9.0%, and inter assay precision from 1.8 to 5.6% and enabled LOD as low as 5 ng g^-1. The concentration of bisphenol S in all of the three brands of BPA-free thermal papers evaluated ranged from 1.36 to 6.77 μg g^-1, and the concentrarion of BPA ranged from 6.56 to 16.4 μg g^-1 in all samples of thermal paper evaluated. The PSI-MS method described here was comparable to the conventional ones, such as liquid chromatography coupled with mass spectrometry and gas chromatography coupled with mass spectrometry described in the literature. The present study proved to be practical, fast, and efficient for the direct determination of bisphenol S in thermal papers. Furthermore, the methodology here described showed to be a promising alternative to replace the classical methods for determination of bisphenol S, due to its simplicity, and no needing of any sample pretreatment.

Development and validation of an ultra performance liquid chromatography-tandem mass spectrometry method for twelve bisphenol compounds in animal feed

Bisphenol compounds (BPs) are a group of environmental contaminants with endocrine-disrupting effects both for humans and animals. The present work developed a sensitive analytical method for the detection of multiple BPs in the animal feed based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with post-column ammonium hydroxide (NH₄OH) infusion. A modified QuEChERS method was incorporated into the extraction and purification processes. The limit of detection (LODs) and quantification (LOQs) for the target BPs were in the ranges of 0.02-0.75 μg kg^-1 and 0.04-0.95 μg kg^-1, respectively. Average recoveries were ranged between 82.6% and 112%. The proposed method was successfully applied to determine the concentrations of BPs in 20 actual feed samples, and the preliminary profiles of BPs in products from local feed factories were obtained. Each sample was simultaneously contaminated with at least 2 to 4 BPs, and bisphenol A (BPA) was the dominant analog of BPs found in animal feed.

Rapid exposure monitoring of six bisphenols and diethylstilbestrol in human urine using fabric phase sorptive extraction followed by high performance liquid chromatography - photodiode array analysis

A novel fabric phase sorptive extraction protocol is developed for rapid exposure monitoring of six bisphenol analogues, including bisphenol A, bisphenol S, bisphenol F, bisphenol E, bisphenol B, bisphenol C, and diethylstilbestrol (DES) from human urine prior to high-performance liquid chromatography-photodiode array analysis. FPSE sample pretreatment protocol ensures the harmonization of the proposed method with the principles of Green Analytical Chemistry (GAC). Among eighteen evaluated FPSE membranes, sol-gel poly (ethylene glycol) (PEG) coated cellulose FPSE membrane resulted in the most efficient extraction. This polar FPSE membrane effectively exploits a number of advantageous features inherent to FPSE including sponge-like porous architecture of the sol-gel sorbent coating, favorable surface chemistry, flexibility and built-in permeability of cellulose fabric substrate, high primary contact surface area for rapid sorbent-analyte interaction, expanded pH, solvent and thermal stability as well as reusability of the FPSE membrane. Optimization was centered on the evaluation of critical parameters, namely the size of the FPSE membrane, the elution solvent mixture, the volume of the sample, the extraction time, the elution time, the kind of the external agitation mechanical stimulus, the ionic strength and the pH of the sample. The chromatographic separation was achieved on a Spherisorb C18 column and a gradient elution program with mobile phase consisted of 0.05 ammonium acetate solution and acetonitrile. The total analysis time was 17.4 min. The developed method was validated in terms of linearity, sensitivity, selectivity, precision, accuracy, stability, and ruggedness. The limits of detection and quantification varied from 0.26-0.62 ng/mL and 0.8-1.9 ng/mL, respectively. The relative recoveries were calculated between 90.6 and 108.8%, while the RSD values were <10% in all cases. The effectiveness of the proposed method was confirmed by its successful implementation in the bioanalysis of real urine samples.

Quality Control of Protein Supplements: A Review

The growing consumer awareness regarding health and fitness has been leading to a huge rise in the consumption of nutritional supplements and, consequently, to an increase in concerns about their quality. In this sense, one of the most consumed products is protein supplements and, despite being safer than other types of supplements, there are several studies showing incompatibilities between what is present on the labels and their actual content. Therefore, this review is focused on gathering information about the problems arising from poor manufacturing practices and inadequate quality control of sport protein supplements. These issues are mainly related to three aspects: reduction of the supplements’ nutritional value, the presence of pharmacological substances, and contamination with microorganisms or toxic metals. Regarding the first aspect, reports about the “classic” addition of nitrogen-rich compounds to mask the protein content measured by the Kjeldahl method were discussed, as well as recent topics such as the addition of cheaper proteins to produce an “undetectable” adulteration in whey protein supplements. With respect to the presence of pharmacological compounds, it is a finding that is not very common in protein supplements; however, even trace amounts of foreign substances in this type of product may cause adverse effects to consumers, and, in the case of an elite athlete, may result in doping. Finally, we discuss about the contamination with microorganisms and toxic metals, this latter being a subject that should be further explored due to few studies in the literature.

Bisphenol A and S in the Urine of Newborns: Plastic for Non-Food Use Still without Rules

Simple Summary

The aim of our study was to assess the effects of Bisphenols exposure on pregnancy and neonatal life. In this optic, we have: (a) determined Bisphenols concentration levels (Bisphenol A and Bisphenol S) in a group of newborns and their mothers, (b) identified factors, habits and devices possibly responsible for Bisphenols uptake, and (c) determined some possible health effect of Bipshenols exposure. The statistical analyses showed no significant correlations between maternal and neonatal Bisphenols concentration levels. In newborns, on the contrary, a positive correlation between pacifier use and Bisphenol S total and free concentration was detected. Beside, a significant correlation was also found between oral glucose administration and concentration levels of free Bisphenols A. Our study points to a central role of lifestyle, hospital procedures and neonatal devices in inducing Bisphenols exposure during perinatal period. This is the first report of Bisphenols contamination in newborns due to widely non-alimentary products destined for newborn care (glucose solution containers for Bisphenol A and the pacifiers for the Bisphenol S). Further studies are advocated to clarify both the impact of such other Bisphenols forms on human health and the potential Bisphenol A exposure sources during neonatal and childhood life.

Abstract

The aim of the present study was to assess the effects of bisphenol (BP) exposure on pregnancy and neonatal life. We have (a) determined BP (BPA and BPS) concentration levels in a group of newborns and their mothers; (b) identified factors, habits, and devices possibly responsible for BP uptake; and (c) determined the effect of BP exposure. No significant correlations were detected between maternal and neonatal BP concentration levels. In newborns, positive correlations between pacifier use and BPS total (p = 0.04) and free BPS (p = 0.03) concentrations were detected. A significant correlation was also found between oral glucose administration and concentration levels of free BPA (p < 0.05). Our study points to a central role of lifestyle, hospital procedures, and neonatal devices in inducing BP exposure, especially during the perinatal period. This is the first report of BP contamination in newborns due to widely non-alimentary products designed for newborn care, such as glucose-solution containers for BPA and pacifiers for BPS. Further studies are advocated in order to clarify both the impact of other BP forms on human health and development, as well as potential BPA exposure sources during neonatal and childhood life.

[Research progress of microextraction by packed sorbent and its application in microvolume sample extraction]

Microextraction is a rapidly developing sample preparation technology in the field of analytical chemistry, which is seeing widespread application. Accurate sample preparation can not only save time but also improve the efficiency of analysis, determination, and data quality. At present, sample pretreatment methods must be rapid, allow for miniaturization, automation, and convenient online connection with analytical instruments. To meet the requirements of green analytical methods and improve the extraction efficiency, microextraction techniques have been introduced as suitable replacements to conventional sample preparation and extraction methods. Microextraction using a packed sorbent (MEPS) is a new type of sample preparation technology. The MEPS equipment was prepared using microsyringe with a volume of 50-500 μL, including MEPS syringes and MEPS adsorption beds (barrel insert and needle, BIN), which is essentially similar to a miniaturized solid phase extraction device. The BIN contains the adsorbent and is built into the syringe needle. A typical MEPS extraction procedure involves repeatedly pumping the sample solution in two directions (up and down) through the adsorbent multiple times in the MEPS syringe. The specific operation course of MEPS includes conditioning, loading, washing, elution, and introduction into the analysis instrument. The conditioning process is adopted to infiltrate the dry sorbent and remove bubbles between the filler particles. The adsorption process is accomplished by pulling the liquid plunger of the syringe so that the sample flows through the adsorbent in both directions multiple times. The washing process involves rinsing the sorbent to remove unwanted components after the analyte is retained. The elution process involves the use of an eluent to ensure that the sample flows through the adsorbent in both directions multiple times, so that elution can be realized by the pumping-pushing action. The target analyte is eluted with the eluent, which can be directly used for chromatographic analysis. However, when processing complex biological matrix samples by MEPS, pretreatment steps such as dilution of the sample and removal of proteins are commonly required. At present, the operation modes of the MEPS equipment are classified into three types: manual, semi-automated, and fully automated. This increase in the degree of automation is highly conducive to processing extremely low or extremely high sample volumes. Critical factors affecting the MEPS performance have been investigated in this study. The conditions for MEPS optimization are the operating process parameters, including sample flow rate, sample volume, number of sample extraction cycles, type and volume of the adsorbent, and elution solvents. It is also necessary to consider the effect of the sample matrix on the performance of MEPS. The MEPS sorbent should be cleaned by a solvent to eliminate carryover and reuse. The sorbent is a core aspect of MEPS. Several types of commercial and non-commercial sorbents have been used in MEPS. Commercial sorbents include silica-based sorbents such as unmodified silica (SIL), C2, C8, and C18. Unmodified silicon-based silica is a normal phase adsorption material, which is highly polar and can be used to retain polar analytes. C18, C8, and C2 materials are suitable for reversed-phase adsorption, while SCX, SAX, APS, and M1 (C8+SCX) adsorbents are suitable for the mixed-mode and ion-exchange modes. Noncommercial sorbents include molecularly imprinted materials, restricted-access molecularly imprinted materials, graphitized carbon, conductive polymer materials, modified silicon materials, and covalent-organic framework materials. The performance of MEPS has recently been illustrated by online with LC-MS and GC-MS assays for the analysis of biological matrices, environmental samples, and food samples. Pretreatment in MEPS protocols includes dilution, protein precipitation, and centrifugation in biological fluid matrices. Because of the small sample size, fast operation, etc., MEPS is expected to be more widely used in the analysis of bio-matrix samples. MEPS devices could also play an important role in field pretreatment and analysis.

Occurrence of Bisphenols and Benzophenone UV Filters in White-Tailed Eagles (Haliaeetus albicilla) from Smøla, Norway

There is a growing concern about the occurrence of bisphenols and benzophenone UV filters in natural ecosystems, while data are limited regarding their actual occurrence in wildlife species, especially in raptors. In this study, concentrations of bisphenol and benzophenone UV filter analogues were determined in liver tissue samples (n = 38) from white-tailed eagles (Haliaeetus albicilla) that were found dead in Smøla (2006-2018), which is a Norwegian municipality that holds one of the densest breeding populations of white-tailed eagles in Europe. Bisphenol AF (BPAF; a fluorinated analogue) was the most ubiquitous contaminant since it was detected in 32 liver samples at concentrations ranging from 1.08 to 6.68 ng/g wet weight (w.w.), followed by bisphenol A (BPA, mean 10.4 ng/g w.w.), benzophenone-1 (BzP-1, mean 3.24 ng/g w.w.), and 4-hydroxybenzophenone (4-OH-BzP, mean 0.62 ng/g w.w.). The concentrations found in livers suggested that white-tailed eagles potentially accumulate bisphenols and benzophenone UV filters, which raises concern, as these plastic and personal care product-related emerging contaminants can show endocrine-disrupting properties. The high detection frequency of the fluorinated BPAF warrants further attention as other fluorinated compounds have proven to be extremely persistent and potentially harmful to wildlife.

Latest Advances in Determination of Bisphenols with Nanomaterials, Molecularly Imprinted Polymers and Aptamer Based Electrochemical Sensors

Contamination of environmental sources such as soils, sediments and rivers and human exposure caused by several endocrine disrupting compounds (EDCs) are considered as the most challenging issues of today's world. EDCs cover a wide variety of compounds ranging from phthalates to parabens and bisphenols (BPs) are the leading group among them. BPs are widely used during the production of different plastic materials such as food and beverage containers, toys, medical equipment and baby bottles that we use in every aspect of our lives. BPs may migrate from those products to different media under certain conditions and this situation causes chronic exposure for humans and other creatures in the environment. Especially bisphenol A (BPA) and its other analogues such as bisphenol F, bisphenol S and tetrabromobisphenol that have similar structures and are preferred as alternatives to BPA cause harmful adverse effects such as endocrine disruption, neurotoxicity, genotoxicity and cytotoxicity. There are legal restrictions and prohibitions by the European Union (EU) in order to prevent possible harmful effects. Therefore, it is important to develop highly sensitive, fast, easy to use and cheap sensors for the determination of BPs in biological, environmental and commercial samples. Electrochemical sensors, which are one of the most widely, used analytical techniques, provide these conditions. Additionally, it is possible to enhance the performance of electrochemical sensors with nanomaterials, molecularly imprinted polymers or aptamer based technologies. This review aims to give comprehensive information about BPs with summarizing most recent applications of electrochemical sensors for their determination in different samples.

Development and Validation of an Analytical Method for Quantitation of Bisphenol S in Rodent Plasma, Amniotic Fluid and Fetuses by UPLC-MS-MS

Bisphenol S (BPS) has been detected in personal care products, water, food and indoor house dust, demonstrating the potential for human exposure. Due to limited data to characterize the hazard of BPS, the National Toxicology Program (NTP) is investigating the toxicity of BPS in rodent models. Generating systemic exposure data is integral to putting toxicological findings into context. The objective of this work was to develop and validate a method to quantitate free (unconjugated parent) and total (free and all conjugated forms of) BPS in rodent plasma, amniotic fluid and fetal homogenate in support of NTP studies. The method used incubation with (total BPS) and without (free BPS) deconjugating enzyme and then protein precipitation followed by ultra-performance liquid chromatography-tandem mass spectrometry. In Sprague Dawley rat plasma, the method was linear (r ≥ 0.99) over the range 5-1,000 ng/mL, accurate (mean relative error (RE) ≤ ±10.5%) and precise (relative standard deviation (RSD) ≤ 7.7%). Mean recoveries were ≥93.1% for both free and total analyses. The limits of detection were 1.15 ng/mL (free) and 0.862 ng/mL (total) in plasma. The method was evaluated in the following study matrices: (i) male Hsd:Sprague Dawley®SD® (HSD) rat plasma, (ii) female HSD rat plasma, (iii) male B6C3F1 mouse plasma, (iv) female B6C3F1 mouse plasma, (v) HSD rat gestational day (GD) 18 dam plasma, (vi) HSD rat GD 18 amniotic fluid, (vii) HSD rat GD 18 fetal homogenate and (viii) HSD rat postnatal day 4 pup plasma (mean %RE ≤ ±8.2 and %RSD ≤ 8.7). Stability of BPS in extracted samples was demonstrated for up to 7 days at various temperatures, and freeze-thaw stability was demonstrated after three cycles over 7 days. BPS in various matrices stored at -80°C for at least 60 days was within 92.1-115% of Day 0 concentrations, demonstrating its stability in these matrices. These data demonstrate that this simple method is suitable for determination of free and total BPS in plasma, amniotic fluid and fetuses following exposure of rodents to BPS.

Biomarkers, matrices and analytical methods targeting human exposure to chemicals selected for a European human biomonitoring initiative

The major purpose of human biomonitoring is the mapping and assessment of human exposure to chemicals. The European initiative HBM4EU has prioritized seven substance groups and two metals relevant for human exposure: Phthalates and substitutes (1,2-cyclohexane dicarboxylic acid diisononyl ester, DINCH), bisphenols, per- and polyfluoroalkyl substances (PFASs), halogenated and organophosphorous flame retardants (HFRs and OPFRs), polycyclic aromatic hydrocarbons (PAHs), arylamines, cadmium and chromium. As a first step towards comparable European-wide data, the most suitable biomarkers, human matrices and analytical methods for each substance group or metal were selected from the scientific literature, based on a set of selection criteria. The biomarkers included parent compounds of PFASs and HFRs in serum, of bisphenols and arylamines in urine, metabolites of phthalates, DINCH, OPFRs and PAHs in urine as well as metals in blood and urine, with a preference to measure Cr in erythrocytes representing Cr (VI) exposure. High performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) was the method of choice for bisphenols, PFASs, the HFR hexabromocyclododecane (HBCDD), phenolic HFRs as well as the metabolites of phthalates, DINCH, OPFRs and PAHs in urine. Gas chromatographic (GC) methods were selected for the remaining compounds, e.g. GC-low resolution MS with electron capture negative ionization (ECNI) for HFRs. Both GC-MS and LC-MS/MS were suitable for arylamines. New developments towards increased applications of GC-MS/MS may offer alternatives to GC-MS or LC-MS/MS approaches, e.g. for bisphenols. The metals were best determined by inductively coupled plasma (ICP)-MS, with the particular challenge of avoiding interferences in the Cd determination in urine. The evaluation process revealed research needs towards higher sensitivity and non-invasive sampling as well as a need for more stringent quality assurance/quality control applications and assessments.

Tetrachlorobisphenol A induced immunosuppression and uterine injury in mice

Tetrachlorobisphenol A (TCBPA) is used as flame retardant, and it has been widely detected in the environmental and human samples. TCBPA is an endocrine disrupting chemical, but its effects on the immune system remains poorly understood. Here the effects of TCBPA on immune system were studied using combined in vivo and in vitro assays. Results showed that TCBPA could suppress the immune response in BALB/c mice via reducing the ratio of CD3⁺ T lymphocytes to regulatory T cells. Moreover, TCBPA exposure significantly induced the increasing secretion of four pro-inflammatory cytokines (IL-2, IL-12, IFN-γ, and TNF-α) and four anti-inflammatory cytokines (IL-4, IL-5, IL-10, GM-CSF) in mice serum. Interestingly, uterine edema was observed in over 80% TCBPA-treated mice after 14- day exposure. TCBPA was detected in 18.6% serum samples of 150 female volunteers in this study. Therefore, our findings provided evidence that TCBPA exposure may cause adverse outcomes on immune system and uterus, suggesting that environmental exposure of TCBPA, as well as its adverse effects on human health should be of concern.

Application of microextraction techniques in alternative biological matrices with focus on forensic toxicology: a review

The interest in alternative biological matrices (e.g., hair and saliva) for forensic toxicology analysis has increased, and recent developments in sample preparation have targeted rapid, cheap, efficient and eco-friendly methods, including microextraction techniques. For this review, we have gathered information about these two hot topics. We discuss the composition, incorporation of analytes and advantages and disadvantages of different biological matrices, and also present the operation principles of the most reported microextraction procedures and their application in forensic toxicology. The outcome of this review may encourage future forensic researches into alternative samples and microextraction techniques.

In Situ Laser-Induced Fabrication of a Ruthenium-Based Microelectrode for Non-Enzymatic Dopamine Sensing

In this paper, we propose a fast and simple approach for the fabrication of the electrocatalytically active ruthenium-containing microstructures using a laser-induced metal deposition technique. The results of scanning electron microscopy and electrical impedance spectroscopy (EIS) demonstrate that the fabricated ruthenium-based microelectrode had a highly developed surface composed of 10 μm pores and 10 nm zigzag cracks. The fabricated material exhibited excellent electrochemical properties toward non-enzymatic dopamine sensing, including high sensitivity (858.5 and 509.1 μA mM⁻¹ cm⁻²), a low detection limit (0.13 and 0.15 μM), as well as good selectivity and stability.

A fast-multiclass method for the determination of 21 endocrine disruptors in human urine by using vortex-assisted dispersive liquid-liquid microextraction (VADLLME) and LC-MS/MS

Simplicity, speed, and reduced cost are essential demands for routine analysis in human biomonitoring studies. Moreover, the availability of higher volumes of human specimens is becoming more restrictive due to ethical controls and to the costs associated with sample transportation and storage. Thus, analytical methods requiring much lower sample volumes associated with simultaneous detection capability (multiclass analysis) are with a very high claim. In this sense, the present approach aimed at the development of a method for preconcentration and simultaneous determination of four classes of endocrine disruptors (seven bisphenols, seven parabens, five benzophenones, and two antimicrobials) in the urine. The approach is based on vortex-assisted dispersive liquid-liquid microextraction (VADLLME) and high-performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). After optimization of the significant parameters of VADLLME extraction, the proposed procedure showed to be simple, fast, sensitive, requiring only 1.0 mL of urine, 400 μL of organic solvents with a total stirring time of 20 s. Moreover, a variation of inter-day and between-day runs were lower than 10.0% and 11.0%, respectively. Finally, the proposed method was successfully applied to the analysis of 50 urine samples of Brazilian pregnant women to establish reference ranges.

Biomonitoring of bisphenols A and S and phthalate metabolites in hair from pregnant women in Crete

Phthalates, bisphenols A and S (BPA, BPS) are used as plasticizers and many of them are documented or suspected of being endocrine disruptors. Several studies indicate that exposure during pregnancy may affect the newborn's health and development. The aim of this cross-sectional study is the biomonitoring of seven phthalate metabolites, BPA and BPS in hair from 100 pregnant women in Crete. The most frequently detected compounds were monoethylhexyl phthalate (mEHP) (68%), mono isobutyl phthalate (miBP) (40%), BPA (37%), BPS (34%) and mono-n-butyl phthalate (mnBP) (28%). Phthalate metabolites were detected at medians from 19.5 to 44.4 pg/mg, BPA at 69.9 pg/mg and BPS at 3.5 pg/mg. Significant positive correlations between phthalate metabolites were found which indicated their common sources of exposure. The frequent use of plastics for food storage was strongly associated with mEHP (p = .013) and a weaker association was found for miBP (p = .063). The frequent use of cosmetics during or before pregnancy was associated with levels of phthalate metabolites in hair. More specifically, the use of hair spray before pregnancy was significantly correlated with monobenzyl phthalate (mBzP) (p = .041) and a trend was found for miBP (p = .066). The use of makeup products during pregnancy was strongly associated with miBP (p = .015) and the use of deodorant during pregnancy was inversely associated with mEHP (p = .021). Strong associations came up between mEHP and lower birth weight (Spearman correlation coefficient, r = -0.302, p = .021) and exposure to BPS was associated with increased body mass index of the participants (p = .036). Although data in literature on biomonitoring of the compounds in hair are limited, the findings of this study are promising and in agreement with existing data in hair or urine.

In vitro estrogenic activity of binary and multicomponent mixtures with bisphenol A

Bisphenol A and its analogs are environmental contaminants with well known estrogenic and anti-androgenic activities. In studies of human biomonitoring, simultaneous exposure to multiple bisphenols was shown in different biological samples, at picomolar to low nanomolar concentrations. Evaluation of their combined toxicities will therefore be a more realistic and reliable predictor for estimation of health risks than evaluation of only the single chemicals. In the present study, estrogenic activities of individual bisphenols were evaluated, along with their binary and multicomponent mixtures including three- and four-component mixtures, using the Organisation for Economic Co-operation and Development validated transactivation assay with the hERα-Hela9903 cell line. Concentration-dependent estrogenic activity was confirmed for all of the tested bisphenols, in the nanomolar to micromolar range. Estrogenic activities of binary and multicomponent mixtures followed a concentration addition model. Although exposure to individual bisphenols remains below their effective doses, we demonstrate that as a mixture, they can contribute additively to toxicity. This study thus emphasizes the importance of mixture toxicity evaluation for risk assessment of compounds that act like the bisphenols.

Rapid, sensitive and simultaneous determination of 16 endocrine-disrupting chemicals (parabens, benzophenones, bisphenols, and triclocarban) in human urine based on microextraction by packed sorbent combined with liquid chromatography tandem mass spectrometry (MEPS-LC-MS/MS)

A high demand exists in human biomonitoring studies for reliable and straightforward methods that generate data faster and simultaneously. Thus, the present study combines microextraction by packed sorbent (MEPS) and liquid chromatography coupled to mass spectrometry (LC-MS/MS) for simultaneous extraction and determination of various classes of endocrine-disrupting chemicals (EDCs), including parabens, benzophenones, bisphenols, and the antimicrobial, triclocarban in human urine samples. Optimized MEPS conditions were: i) MEPS sorbent (C18), ii) pH of sample (3), iii) volume of sample (250 μL), iv) number of draws-eject cycles (5) and (vi) desorption solvent conditions (100 μL of CH₃OH:H₂O 80:20 v/v). The calibration curves were linear over the selected ranges for all studied compound, with correlation coefficients higher than 0.99. The variation coefficient for precision was lower than 20% at lower concentrations and lower than 15% at the higher concentrations studied. The accuracy ranged from 90% to 118%. The proposed strategy affords several advantages over currently published approaches, including simplicity of operation and reduction of sample and solvent volumes and time for matrix clean-up. Moreover, the analytical performance of each MEPS cartridge remained stable over the analysis of at least 70 samples (RSD < 10%). Thus, the current procedure may be an interesting high-throughput alternative for large routine human biomonitoring studies. Urinary geometric mean concentrations of EDCs obtained in this study were close than those previously reported for Brazilian children.

Bisphenol AF compromises blood-testis barrier integrity and sperm quality in mice

The profound influence of environmental chemicals on human health including inducing life-threatening gene mutation has been publicly recognized. Being a substitute for the extensively used endocrine-disrupting chemical BPA, Bisphenol AF (BPAF) has been known as teratogen with developmental toxicities and therefore potentially putting human into the risk of biological hazards. Herein, we deciphered the detrimental effects of BPAF on spermatogenesis and spermiotiliosis in sexual maturity of mice exposing to BPAF (5, 20, 50 mg/kg/d) for consecutive 28 days. BPAF exposure significantly compromises blood-testis barrier integrity and sperm quantity and quality in a dose-dependent manner. Sperms from BPAF exposure mice are featured by severe DNA damage, altered SUMOylation and ubiquitination dynamics and interfered epigenetic inheritance with hypermethylation of H3K27me3 presumably due to the aggregation of cellular reactive oxygen species (ROS). Furthermore, BPAF treatment (50 μM for 24 h) compromises cytoskeleton architecture and tight junction permeability in primary cultured Sertoli cells evidenced by dysfunction of actin regulatory proteins (e.g. Arp3 and Palladin) via activation of ERK signaling, thereby perturbing the privilege microenvironment created by Sertoli cells for spermatogenesis. Overall, our study determines BPAF is deleterious for male fertility, leading to a better appreciation of its toxicological features in our life.

An overview of the current progress, challenges, and prospects of human biomonitoring and exposome studies

Human Biomonitoring (HB), the process for determining whether and to what extent chemical substances penetrated our bodies, serves as a useful tool to quantify human exposure to pollutants. In cases of nutrition and physiologic status, HB plays a critical role in the identification of excess or deficiency of essential nutrients. In pollutant HB studies, levels of substances measured in body fluids (blood, urine, and breast milk) or tissues (hair, nails or teeth) aid in the identification of potential health risks or associated adverse effects. However, even as a widespread practice in several countries, most HB studies reflect exposure to a single compound or mixtures which are measured at a single time point in lifecycle. On the other hand, throughout an individual's lifespan, the contact with different physical, chemical, and social stressors occurs at varying intensities, differing times and durations. Further, the interaction between stressors and body receptors leads to dynamic responses of the entire biological system including proteome, metabolome, transcriptome, and adductome. Bearing this in mind, a relatively new vision in exposure science, defined as the exposome, is postulated to expand the traditional practice of measuring a single exposure to one or few chemicals at one-time point to an approach that addresses measures of exposure to multiple stressors throughout the lifespan. With the exposome concept, the science of exposure advances to an Environment-Wide Association Perspective, which might exhibit a stronger relationship with good health or disease conditions for an individual (phenotype). Thus, this critical review focused on the current progress of HB and exposome investigations, anticipating some challenges, strategies, and future needs to be taken into account for designing future surveys.