Matrix solid phase dispersion for the extraction of selected endocrine disrupting chemicals from human placental tissue prior to UHPLC-MS/MS analysis

Prenatal exposure to low doses of benzophenone-3 elicits disruption of cortical vasculature in fetuses through perturbations in Wnt/β-catenin signaling correlating with depression-like behavior in offspring mice

Benzophenone-3 (BP-3), commonly used in personal care products, is routinely detected in environmental and human matrices. Evidence delineates a correlation between gestational BP-3 exposure and emotional and social disorders in children and adolescents. However, sensitive target cells and the mode of action underlying the early responses to environmentally relevant level of BP-3 exposure remain unclear. In this study, 0.3 and 3 mg/kg of BP-3 were administered to pregnant mice. Compared with the control group, the cortical blood vessel development process manifested the highest susceptibility to BP-3 exposure using transcriptomic sequencing at embryonic day 14 (E14). Notably, the diminution in vascular density and tight junction proteins presence was observed in the fetal cortex at E14, concomitant with the suppressed transcriptional activity of genes essential to angiogenesis and barrier formation. Strikingly, the investigation revealed that BP-3 exposure impeded vascular sprouting in aortic ring explants and neuroendothelial migration, implicating the Wnt/β-catenin signaling pathway. Moreover, BP-3 exposure compromised perivascular neural stem cell differentiation. Cortical vascular injury correlated with the exhibition of depression-like behavior in four-week postnatal progeny. These insights underscore the cerebrovasculature as an early sensitive target for low doses of BP-3 exposure, fostering the development of biomarkers and the establishment of the adverse outcome pathway framework for BP-3 hazard evaluation.

Bisphenol S and Its Chlorinated Derivatives in Indoor Dust and Human Exposure

Bisphenol S (BPS), an environmental endocrine disruptor, has been identified in global environmental matrices. Nevertheless, limited studies have investigated the presence of chlorinated analogues of BPS (Clx-BPSs) with potential estrogenic activities in environmental matrices. In this study, the occurrence of BPS and five types of Clx-BPSs was characterized in indoor dust (n = 178) from Hangzhou City. BPS was measurable in 94% of indoor dust samples, with an average level of 0.63 μg/g ( Collapse

Key Words

• BPS
• chlorinated BPS
• human intake
• indoor dust
• inhalation exposure

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MESH Headings Collapse

Grants

• LY21B070006 Natural Science Foundation of Zhejiang Province
• LR23D030001 Natural Science Foundation of Zhejiang Province

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Affiliation(s)

Yi Qian Department of Environmental Engineering, Taizhou University, Taizhou 318000, China
Jianqiang Zhu Department of Environmental Engineering, Taizhou University, Taizhou 318000, China
Ruyue Guo Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
Hangbiao Jin Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, China

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Formation of halogenated forms of bisphenol A (BPA) in water: Resolving isomers with ion mobility - mass spectrometry and the role of halogenation position in cellular toxicity

Halogenated BPA (XBPA) forms resulting from water chlorination can lead to increased toxicity and different biological effects. While previous studies have reported the occurrence of different XBPAs, analytical limitation have hindered the analysis and differentiation of the many potential isomeric forms. Using online solid-phase extraction - liquid chromatography - ion-mobility - high-resolution mass spectrometry (OSPE-LC-IM-HRMS), we demonstrated a rapid analysis method for the analysis of XBPA forms after water chlorination, with a total analysis time of less than 10 min including extraction and concentration and low detection limits (∼5-80 ng/L range). A multi in-vitro bioassay testing approach for the identified products revealed that cytotoxicity and bioenergetics impacts were largely associated with the presence of halogen atoms at positions 2 or 2' and the overall number of halogens incorporated into the BPA molecule. Different XBPA also showed distinct impacts on oxidative stress, peroxisome proliferator-activated receptor gamma - PPARγ, and inflammatory response. While increased DNA damage was observed for chlorinated water samples (4.14 ± 1.21-fold change), the additive effect of the selected 20 XBPA studied could not explain the increased DNA damage observed, indicating that additional species or synergistic effects might be at play.

Optimized extraction and analysis methods using liquid chromatography-tandem mass spectrometry for zearalenone and metabolites in human placental tissue

Zearalenone and its metabolites, a group of endocrine disrupting mycotoxins, have been linked to adverse reproductive health effects. They cross the placental barrier, potentially reaching the fetus. In this study, we adapted and optimized our protocol previously used for urine, to measure these mycotoxins in human placentas. We combined a supported liquid extraction step using Chem Elut cartridges with solid phase extraction on Discovery® DSC-NH2 tubes. The optimized extraction efficiencies were between 68 and 80% for all metabolites. Analysis was performed by UHPLC-HRMS using a Betasil™ Phenyl-Hexyl column eluted with a gradient of acetonitrile-methanol-water. The chromatography method separated all analytes in under 15 min. Validation experiments confirmed the method's sensitivity, with LODs ranging from 0.0055 to 0.011 pg/mg tissue. The method was linear over a range of 0.0025-1.5 pg/mg tissue with R2 values ≥ 0.994. Precision and accuracy calculations ranged from 4.7-7.9% and 0.6-6.7% respectively. The method was then successfully applied to a subset of placenta samples (n = 25) collected from an ongoing prospective birth cohort. Interestingly, 92% of the samples contained at least one measurable zearalenone metabolite, providing initial indication of potentially widespread exposure during pregnancy.

Assessment of human exposure to benzophenone-type UV filters: A review

To avoid the harmful effects of UV radiation, benzophenone-type UV filters (BPs) are widely used in personal care products and other synthetic products. Biomonitoring studies have shown the presence of BPs in various human biological samples, raising health concerns. However, there is a paucity of data on the global human exposure to this group of contaminants. In this study, we compiled data on the body burden of BPs along with the possible exposure routes and biotransformation pathways. BPs can easily penetrate the skin barrier and thus, they can be absorbed through the skin. In the human body, BPs can undergo Phase I (mainly demethylation and hydroxylation) and Phase II (mainly glucuronidation and sulfation) biotransformations. From a total of 158 studies, most of the studies are related to urine (concentration up to 92.7 mg L^-1), followed by those reported in blood (up to 0.9 mg L^-1) and milk (up to 0.8 mg L^-1). Among BPs, benzophenone-1 and benzophenone-3 are the most commonly detected congeners. The body burden of BPs is associated with various factors, including the country of residence, lifestyle, income, education level, and ethnicity. The presence of BPs in maternal urine (up to 1.1 mg L^-1), placenta (up to 9.8 ng g^-1), and amniotic fluid (up to 15.7 μg L^-1) suggests potential risks of prenatal exposure. In addition, transplacental transfer of BPs is possible, as demonstrated by their presence in maternal serum and cord serum. The possible association of BPs exposure and health effects was discussed. Future human biomonitoring studies and studies on the potential health effects are warranted. Overall, this review provides a summary of the global human exposure to BPs and can serve as supporting evidence to guide usage in order to protect humans from being exposed to BPs.

C18-modified halloysite as a novel sorbent in matrix solid-phase dispersion for the extraction of bisphenol A and diethylstilbestrol from human placenta

In the current study, the C18-modified halloysite was fabricated via silylation reaction and subsequently used as sorbent in matrix solid-phase dispersion (MSPD) for the extraction of bisphenol A and diethylstilbestrol from human placenta, followed by high-performance liquid chromatography-tandem mass spectrometry analysis. The as-prepared sorbent was characterized by scanning electron microscopy, energy-dispersive spectrometry, Fourier transform infrared spectroscopy, X-ray diffraction, and thermo-gravimetric analysis. Varied parameters such as methanol concentration in wash solvent, pH and salt concentration in elution solvent, elution volume, and mass ratio of sample to sorbent were optimized. The adsorption capacities of bisphenol A and diethylstilbestrol on the developed C18-modified halloysite were 6.3 and 14.2 mg g^-1, respectively, higher than those on the commercial C18 silica gel. Under the optimal condition, the average recoveries of bisphenol A and diethylstilbestrol by MSPD varied from 91.0 to 106.0%, and the relative standard deviations were less than 10.6% for human placenta samples. The limits of detection in the human placenta were 0.2 μg kg^-1 for bisphenol A and diethylstilbestrol. The simple C18-modified halloysite-based MSPD method holds great potential for the determination of trace bisphenol A and diethylstilbestrol in the human placenta and other tissues of pregnant women with high sensitivity, accuracy, and reliability.

In utero exposure to endocrine-disrupting chemicals, maternal factors and alterations in the epigenetic landscape underlying later-life health effects

Widespread persistence of endocrine-disrupting chemicals (EDCs) in the environment has mandated the need to study their potential effects on an individual's long-term health after both acute and chronic exposure periods. In this review article a particular focus is given on in utero exposure to EDCs in rodent models which resulted in altered epigenetic programming and transgenerational effects in the offspring causing disrupted reproductive and metabolic phenotypes. The literature to date establishes the impact of transgenerational effects of EDCs potentially associated with epigenetic mediated mechanisms. Therefore, this review aims to provide a comprehensive overview of epigenetic programming and it's regulation in mammals, primarily focusing on the epigenetic plasticity and susceptibility to exogenous hormone active chemicals during the early developmental period. Further, we have also in depth discussed the epigenetic alterations associated with the exposure to selected EDCs such as Bisphenol A (BPA), di-2-ethylhexyl phthalate (DEHP) and vinclozlin upon in utero exposure especially in rodent models.

Dietary exposure to parabens and body mass index in an adolescent Spanish population

Parabens are alkyl esters of p-hydroxybenzoic acid which are extensively used in cosmetics, pharmaceuticals and foodstuffs due to their antimicrobial properties. The most commonly used parabens are methyl-(MeP), ethyl-(EtP), propyl-(PrP) and butyl-(BuP) paraben. Most human exposure to parabens is achieved through the consumption of food or pharmaceutical products and the use of personal care products. However, studies on dietary parabens exposure and the associated factors are very scarce. The main aim of the present study was to explore factors associated with dietary exposure to parabens in Spanish adolescents according to gender. Dietary data and anthropometric measures were collected from 585 adolescents (53.4% boys) aged 12-16 years. Parabens exposure through diet was assessed using a food frequency questionnaire with food products providing more than 95% of energy and macronutrient intake being included in analysis. Stepwise regression was used to identify the foods that most contributed to parabens intake. Logistic regression was used to evaluate factors predicting higher dietary exposure to parabens. The main contributors to dietary MeP, EtP, PrP and BuP exposure in adolescent boys were eggs (41.9%), canned tuna (46.4%), bakery and baked goods products (57.3%) and pineapple (61.1%). In adolescent girls, the main contributors were apples and pears (35.3%), canned tuna (42.1%), bakery and baked goods products (55.1%) and olives (62.1%). Overweight/obese girls were more likely to belong to the highest tertile of overall parabens intake (odds ratio [OR]: 3.32; 95% confidence interval [95% CI]: 1.21-9.15) and MeP (OR: 3.05; 95% CI: 1.14-8.12) than those with a body mass index lower than 25 kg/m². These findings suggest a positive association between dietary exposure to parabens and overweight/obesity in adolescent girls.

An overview of the literature on emerging pollutants: Chlorinated derivatives of Bisphenol A (ClxBPA)

CONTEXT

Bisphenol A (BPA) is a ubiquitous contaminant with endocrine-disrupting effects in mammals. During chlorination treatment of drinking water, aqueous BPA can react with chlorine to form chlorinated derivatives of BPA (mono, di, tri and tetra-chlorinated derivatives) or Cl_xBPA.

OBJECTIVE

The aim of this study is to summarize and present the state of knowledge on human toxicological risk assessment of Cl_xBPA.

MATERIALS AND METHODS

A search on Cl_xBPA in the PubMed database was performed based on studies published between 2002 and 2021. Forty-nine studies on chlorinated derivatives of BPA were found. Available information on their sources and levels of exposure, their effects, their possible mechanisms of action and their toxicokinetics data was extracted and presented.

RESULTS

Cl_xBPA have been essentially detected in environmental aqueous media. There is evidence in toxicological and epidemiological studies that Cl_xBPA also have endocrine-disrupting capabilities. These emerging pollutants have been found in human urine, serum, breast milk, adipose and placental tissue and can constitute a risk to human health. However, in vitro and in vivo toxicokinetic data on Cl_xBPA are scarce and do not allow characterization of the disposition kinetics of these compounds.

CONCLUSION

More research to assess their health risks, specifically in vulnerable populations, is needed. Some water chlorination processes are particularly hazardous, and it is important to evaluate their chlorination by-products from a public health perspective.

Determination of bisphenols, parabens, and benzophenones in placenta by dispersive liquid-liquid microextraction and gas chromatography-tandem mass spectrometry

Human exposure to endocrine disrupting chemicals (EDCs) is of particular concern during development. Bisphenols, parabens, and benzophenones are EDCs widely used in the manufacture of numerous goods, personal care products, and cosmetics. The aim of this study was to develop a new and practical method for determining three bisphenols, four parabens, and five benzophenones in placenta samples. It uses dispersive liquid-liquid microextraction (DLLME) in combination with gas chromatography-tandem mass spectrometry (GC-MS/MS). Several chemometric approaches were employed to optimize the experimental parameters. Limits of detection ranged from 0.04 to 0.08 ng g^-1 and inter-day variabilities (evaluated as relative standard deviation) from 4.2% to 13.4%. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery percentages ranged from 87.1% to 113.2%. Finally, the method was used to measure target compounds in 20 placental tissue samples from voluntary donors. This analytical procedure can provide information on the exposure of the fetus to non-persistent EDCs.

Highly Sensitive Determination of Bisphenol A in Bottled Water Samples by HPLC after Its Extraction by a Novel Th-MOF Pipette-Tip Micro-SPE

In this study, a novel thorium metal organic framework was synthesized, characterized and used as a sorbent for very efficient pipette tip micro solid-phase extraction of bisphenol A in bottled drinking water samples using high-performance liquid chromatography as detecting instrument. Parameters which influence extraction efficiency such as pH, sample volume, amount of sorbent, type and volume of eluent, number of aspirating and dispensing cycles for extraction and elution, and volume of the sample solution were studied and optimized. A linear calibration curve was obtained in the range of 0.002–0.456 ng mL−1 (r2 = 0.996) with a detection limit of 0.0010 ng mL−1. Repeatability of batch-to-batch extraction was better than 5.0% and a reproducibility of 3.2% for real samples obtained.

Simultaneous determination of parabens, bisphenols and alkylphenols in human placenta by ultra-high performance liquid chromatography-tandem mass spectrometry

This study presents de development and validation of an ultra- high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous determination of four parabens (methyl-, ethyl-, propyl-, and butyl-paraben (MeP, EtP, PrP, BuP), four bisphenols (BP) (BPA, BPB, BPF, and BPS) and two alkylphenols (nonyl phenol (NP) and tert-octylphenol (OP) in human placenta samples. After a short sample preparation time the extracts are analysed by UHPLC-MS/MS using negative electrospray ionization. Labeled internal standards and matrix-matched calibration are used for quantification of the compounds. The method was validated according FDA guideline for bio analytical methods using spiked samples at three concentration levels (0.5-5 and 25 ng g^-1). The parameters accuracy and precision fulfill the criteria. Calibration curves are linear between 0.5 and 50 ng ^-1. The limits of detection and quantification are in the range of 0.1-0.3 ng g^-1 and 0.2-0.7 ng g^-1, respectively. The applicability of the method was demonstrated on 71 human placenta samples from a Belgian cohort. The detection frequency was highest for OP (95%), EtP (86%), BPA (49%) and BPS (44%). Among the quantified compounds the highest quantification frequency was observed for OP (85%), EtP (65%) and BPA (25%). The concentrations of parabens ranged from 0.5 to 7.1 ng g^-1 for MeP, from 0.5 to 4.5 ng g^-1 for EtP and from 0.5 to 9.1 ng g^-1 for PrP. The levels of bisphenols ranged from 0.5 to 3.9 ng g^-1 for BPA, from 0.6 to 2.1 ng g^-1 for BPF and from 0.8 to 1.3 ng g^-1 for BPS. BPB and NP were not detected and OP levels ranged from 0.5 to 3.7 ng g g^-1. The results demonstrate that the developed analytical method is very sensitive and that levels of several compounds with known /suspected endocrine disrupting properties could be detected or quantified in human placenta samples. The results therefore suggest that fetal exposure to these compounds occurs. The method will be useful for studies to evaluate the health effects associated with this prenatal exposure.

A magnetic cellulose-based carbon fiber hybrid as a dispersive solid-phase extraction material for the simultaneous detection of six bisphenol analogs from environmental samples

A hollow porous NiMn2O4 nanosphere-decorated cellulose-based carbon fiber (CCF, using recyclable cotton wool as the carbon fiber source) hybrid was fabricated via a relatively green and eco-friendly hydrothermal synthetic route, followed by calcination treatment. The in situ growth of hollow porous NiMn2O4 on the CCFs led to it being decorated over the CCF surface uniformly. The NiMn2O4/CCFs hybrid displayed excellent extraction capabilities and magnetic reusability. Benefiting from its high porosity, large specific surface area, and superior chemical affinities to bisphenol analogs (BPs), and the synergistic effect between NiMn2O4 and CCFs, NiMn2O4/CCFs as an adsorbent was applied to the extraction of low concentrations of BP compounds, displaying excellent extraction capabilities. A magnetic dispersive solid phase extraction (MDSPE) method combined with HPLC was developed for detecting six BPs in real environmental samples. Under optimal conditions, the detection limits and recoveries were 0.56-0.83 ng mL-1 and 84.3-103.5% (RSD ≤ 4.5%). It was confirmed that NiMn2O4/CCFs was a type of rapid and high efficiency MDSPE material for the analysis of multiple BP compounds in environmental samples.

A fast and simple air-assisted liquid-liquid microextraction procedure for the simultaneous determination of bisphenols, parabens, benzophenones, triclosan, and triclocarban in human urine by liquid chromatography-tandem mass spectrometry

The increasing awareness and public concern with hazard exposure to endocrine-disrupting chemicals calls for methods capable to handle numerous samples in short analysis time. In this present study, a novel method combining air-assisted liquid-liquid microextraction and liquid chromatography coupled to mass spectrometry was developed and validated for the extraction, preconcentration, and determination of 7 bisphenols (bisphenol A, bisphenol S, bisphenol AP, bisphenol P, bisphenol F, bisphenol AF, bisphenol Z), 7 parabens (methyl-, ethyl-, propyl-, butyl-, benzyl-paraben, methyl-protocatechuic acid, and ethyl-protocatechuic acid), 5 benzophenones (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-8, and 4-hydroxybenzophenone), and two antimicrobials (triclosan and triclocarban) in human urine samples. Type and volume of solvent, extraction time (cycles), pH sample, ionic strength, agitation, and needle dimensions were evaluated. The matrix-matched calibration curves of all analytes were linear with correlation coefficients higher than 0.99 in the range level of 1.0-20.0 ng mL^-1. The relative standard deviation, precision, at three concentrations (1.0, 10.0 and 20.0 ng mL^-1) was lower than 15% with accuracy ranging from 90% to 114%. The biomonitoring capability of the new proposed method was confirmed with the analysis of 50 human urine samples randomly collected from Brazilian children. High urinary concentrations of several EDCs associated with usage of personal care products were found.

Assessment of parabens and ultraviolet filters in human placenta tissue by ultrasound-assisted extraction and ultra-high performance liquid chromatography-tandem mass spectrometry

Increasing concerns have been raised over recent decades about human exposure to Endocrine Disrupting Chemicals (EDCs), especially about their possible effects on embryo, foetus, newborn, and child. Parabens (PBs) and ultraviolet filters (UV-filters) are prevalent EDCs widely used as additives in cosmetics and personal care products (PCPs). The objective of this study was to determine the presence of four PBs and ten UV-filters in placental tissue samples using a novel analytical method based on ultrasound-assisted extraction (UAE) and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Multivariate optimization strategies were used to accurately optimize extraction and clean-up parameters. Limits of quantification ranged from 0.15 to 0.5μgkg^-1, and inter-day variability (evaluated as relative standard deviation) ranged from 3.6% to 14%. The method was validated using matrix-matched standard calibration followed by a recovery assay with spiked samples. Recovery percents ranged from 94.5% to 112%. The method was satisfactorily applied for the determination of the target compounds in human placental tissue samples collected at delivery from 15 randomly selected women. This new analytical procedure can provide information on foetal exposure to compounds, which has been little studied.

Analysis of four toxic metals in a single rice seed by matrix solid phase dispersion -inductively coupled plasma mass spectrometry

Toxic metals in rice pose great risks to human health. Metal bioaccumulation in rice grains is a criterion of breeding. Rice breeding requires a sensitive method to determine metal content in single rice grains to assist the variety selection. In the present study, four toxic metals of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) in a single rice grain were determined by a simple and rapid method. The developed method is based on matrix solid phase dispersion using multi-wall carbon nanotubes (MWCNTs) as dispersing agent and analyzed by inductively coupled plasma mass spectrometry. The experimental parameters were systematically investigated. The limits of detection (LOD) were 5.0, 0.6, 10 and 2.1 ng g⁻¹ for As, Cd, Cr, and Pb, respectively, with relative standard deviations (n = 6) of <7.7%, demonstrating the good sensitivity and precision of the method. The results of 30 real world rice samples analyzed by this method agreed well with those obtained by the standard microwave digestion. The amount of sample required was reduced approximately 100 fold in comparison with the microwave digestion. The method has a high application potential for other sample matrices and elements with high sensitivity and sample throughput.

Determination of parabens and benzophenone-type UV filters in human placenta. First description of the existence of benzyl paraben and benzophenone-4

UV filters and parabens (PBs) are chemicals used in daily personal care and hygiene products to protect materials and humans from the adverse effects of UV radiation and to preserve the integrity of the formulation, respectively. Several studies highlight their widespread environmental occurrence and endocrine disrupting effects. However, little is known about human exposure to these compounds. The objective of this study was to investigate the exposure of human embryos and foetuses to endocrine disrupting UV filters and PBs. Placentas from volunteer mothers in Barcelona were collected at delivery after informed, written consent by the pregnant women. UV filters and parabens were analysed by liquid chromatography-tandem mass spectrometry. The excellent performance of the method allowed measuring the target compounds in human placental tissue at low ng/g fresh weight level. The detection frequency of the selected compounds was in the range 17-100%. Benzophenone-1, methyl paraben, butyl paraben and benzyl paraben were detected in all samples. The highest measured concentration corresponded to methyl paraben, 11.77ng/g fresh weight. Reported concentrations of benzophenone-4 and benzyl paraben constitute the first evidence about their accumulation in placenta. The results obtained corroborate that foetuses are exposed to a wide diversity of UV filters and PBs via the placenta.

Vortex-homogenized matrix solid-phase dispersion coupled with gas chromatography – electron-capture negative-ion mass spectrometry to determine halogenated phenolic compounds in seafood

This work represents the development of vortex-homogenized matrix solid-phase dispersion (VH-MSPD) as an effective and simple method to rapidly extract halogenated phenolic compounds in marketed seafood samples.

Validated method for the determination of perfluorinated compounds in placental tissue samples based on a simple extraction procedure followed by ultra-high performance liquid chromatography-tandem mass spectrometry analysis

Xenobiotic exposure during pregnancy is inevitable. Determination of perfluorinated compounds (PFCs), chemicals described as environmental contaminants by Public Health Authorities due to their persistence, bioaccumulation and toxicity, is a challenge. In the present work, a method based on a simplified sample treatment involving freeze-drying, solvent extraction and dispersive clean-up of the extracts using C18 sorbents followed by an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis was developed and validated for the determination of five perfluorinated carboxylic acids (C4-C8) and perfluorooctane sulfonate (PFOS) in placental tissue samples. The most influential parameters affecting the extraction method and clean-up were optimized using Design of Experiments (DOE). The method was validated using matrix-matched calibration. Found limits of detection (LODs) ranged from 0.03 to 2 ng g(-1) and limits of quantification (LOQs) from 0.08 to 6 ng g(-1), while inter- and intra-day variability was under 14% in all cases. Recovery rates for spiked samples ranged from 94% to 113%. The method was satisfactorily applied for the determination of compounds in human placental tissue samples collected at delivery from 25 randomly selected women.

Biomonitoring of human exposures to chlorinated derivatives and structural analogs of bisphenol A

The high reactivity of bisphenol A (BPA) with disinfectant chlorine is evident in the instantaneous formation of chlorinated BPA derivatives (ClxBPA) in various environmental media that show increased estrogen-activity when compared with that of BPA. The documented health risks associated with BPA exposures have led to the gradual market entry of BPA structural analogs, such as bisphenol S (BPS), bisphenol F (BPF), bisphenol B (BPB), etc. A suite of exposure sources to ClxBPA and BPA analogs in the domestic environment is anticipated to drive the nature and range of halogenated BPA derivatives that can form when residual BPA comes in contact with disinfectant in tap water and/or consumer products. The primary objective of this review was to survey all available studies reporting biomonitoring protocols of ClxBPA and structural BPA analogs (BPS, BPF, BPB, etc.) in human matrices. Focus was paid on describing the analytical methodologies practiced for the analysis of ClxBPA and BPA analogs using hyphenated chromatography and mass spectrometry techniques, because current methodologies for human matrices are complex. During the last decade, an increasing number of ecotoxicological, cell-culture and animal-based and human studies dealing with ClxBPA exposure sources and routes of exposure, metabolism and toxicity have been published. Up to date findings indicated the association of ClxBPA with metabolic conditions, such as obesity, lipid accumulation, and type 2 diabetes mellitus, particularly in in-vitro and in-vivo studies. We critically discuss the limitations, research needs and future opportunities linked with the inclusion of ClxBPA and BPA analogs into exposure assessment protocols of relevant epidemiological studies.

Selective extraction and determination of fluoroquinolones in bovine milk samples with montmorillonite magnetic molecularly imprinted polymers and capillary electrophoresis

A sensitive and selective method for separating fluoroquinolones (FQs) from bovine milk samples was successfully developed using montmorillonite magnetic molecularly imprinted polymers (MMMIPs) as adsorbents. MMMIPs were prepared using montmorillonite as carrier, fleroxacin (FLE) as template molecule, and Fe3O4 magnetite as magnetic component. MMMIPs possessed high adsorption capacity of 46.3 mg g(-1) for FLE. A rapid and convenient magnetic solid-phase extraction procedure coupled with capillary electrophoresis was established with MMMIPs as adsorbents for simultaneous and selective extraction of four FQs in bovine milk samples. Limits of detection ranged between 12.9 and 18.8 μg L(-1), and the RSDs were between 1.8% and 8.6%. The proposed method was successfully applied to spike bovine milk samples with recoveries of 92.7%-108.6%.

Determination of four paraben-type preservatives and three benzophenone-type ultraviolet light filters in seafoods by LC-QqLIT-MS/MS

For the first time, an efficient and sensitive analytical method based on liquid chromatography-quadrupole linear ion trap-tandem mass spectrometry (LC-QqLIT-MS/MS) was developed for the simultaneous determination of four paraben-type preservatives and three benzophenone-type ultraviolet light filters in both plant (Sargassum fusiforme, porphyra, kelp) and animal (hairtail, yellow croaker, shrimp) seafood. The samples were extracted in methanol by pressurized liquid extraction (PLE), and the extracts were then cleaned up by mixed-mode cationic exchange (MCX) solid-phase extraction cartridges. Both isotope-labeled internal standards and matrix-matched calibration standards were used to alleviate and correct for the matrix effects, and the limits of quantification (LOQs) were 10.0μg kg(-1) for all target compounds. The average recoveries were in the range of 80.6-107.8% at three spiked concentration levels (10, 50 and 100μgkg(-1)) with relative standard deviations (RSDs) below 8.5%. The results suggest that very limited contamination of these seven emerging contaminants, mainly associated with PCPs, occurred in these common seafoods.

Global Assessment of Bisphenol A in the Environment: Review and Analysis of Its Occurrence and Bioaccumulation

Because bisphenol A (BPA) is a high production volume chemical, we examined over 500 peer-reviewed studies to understand its global distribution in effluent discharges, surface waters, sewage sludge, biosolids, sediments, soils, air, wildlife, and humans. Bisphenol A was largely reported from urban ecosystems in Asia, Europe, and North America; unfortunately, information was lacking from large geographic areas, megacities, and developing countries. When sufficient data were available, probabilistic hazard assessments were performed to understand global environmental quality concerns. Exceedances of Canadian Predicted No Effect Concentrations for aquatic life were >50% for effluents in Asia, Europe, and North America but as high as 80% for surface water reports from Asia. Similarly, maximum concentrations of BPA in sediments from Asia were higher than Europe. Concentrations of BPA in wildlife, mostly for fish, ranged from 0.2 to 13 000 ng/g. We observed 60% and 40% exceedences of median levels by the US Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey in Europe and Asia, respectively. These findings highlight the utility of coordinating global sensing of environmental contaminants efforts through integration of environmental monitoring and specimen banking to identify regions for implementation of more robust environmental assessment and management programs.