The new generation PFAS C6O4 does not produce adverse effects on thyroid cells in vitro.

PURPOSE: Per- and poly-fluoroalkyl-substances (PFASs) are synthetic compounds that raised concern due to their potential adverse effects on human health. Long-chain PFAS were banned by government rules in many states, and thus, new emerging PFAS were recently introduced as substitutes. Among these, Perfluoro{acetic acid, 2-[(5-methoxy-1,3-dioxolan-4-yl)oxy]}, ammonium salt (C6O4) was recently introduced to produce a range of food contact articles and literature data about this compound are scanty. The aim of this study was to evaluate the in vitro effects of exposure to C6O4, compared with PFOA and PFOS on thyroid cells. METHODS: FRTL5 rat-thyroid cell lines and normal human thyroid cells (NHT) were incubated with increasing concentrations of C6O4 for 24, 48, 72, and 144 h to assess cell viability by WST-1. Cell viability was confirmed by AnnexinV/PI staining. Long-chain PFAS (PFOA and PFOS) were used at same concentrations as positive controls. The proliferation of cells exposed to C6O4, PFOA, and PFOS was measured by staining with crystal violet and evaluation of optical density after incubation with SDS. Changes in ROS production by FRTL5 and NHT after exposure to C6O4 at short (10, 20, and 30 min) and long-time points (24 h) were evaluated by cytofluorimetry. RESULTS: C6O4 exposure did not modify FRTL5 and NHT cell viability at any concentration and/or time points with no induction of necrosis/apoptosis. At difference, PFOS exposure reduced cell viability of FRTL5 while and NHT, while PFOA only in FRTL5. FRTL5 and NHT cell proliferation was reduced by incubation with by PFOA and PFOS, but not with C6O4. ROS production by NHT and FRTL5 cells was not modified after C6O4 exposure, at any time/concentration tested. CONCLUSIONS: The present in vitro study constitutes the first evaluation of the potential adverse effects of the new emerging PFAS C6O4 in cultured rat and human thyroid cells, suggesting its safety for thyroid cells in vitro.

Succinic anhydride-based chemical modification making laccase@Cu3(PO4)2 hybrid nanoflowers robust in removing bisphenol A in wastewater.

To prepare a robust biocatalyst and enhance the removal of bisphenol A in wastewater, succinic anhydride was reacted with laccase to obtain succinic anhydride-modified laccase (SA-laccase) and then co-crystallized with Cu3(PO4)2 to form SA-laccase@Cu3(PO4)2 hybrid nanoflowers (hNFs). The activity of SA-laccase@Cu3(PO4)2 reached 5.27 U/mg, 1.86-, 2.88- and 2.15-fold those of bare laccase@Cu3(PO4)2, laccase@Ca3(PO4)2 and laccase@epoxy resin, respectively. Compared with free laccase, the obtained hNFs present enhanced activity and tolerance to pH and high temperature in the removal of BPA. Under the optimum conditions of pH 6.0 and 35 °C, BPA removal reached 93.2% using SA-laccase@Cu3(PO4)2 hNFs, which was 1.21-fold of that using free laccase. In addition, the obtained SA-laccase@Cu3(PO4)2 hNFs retained nearly 90% of their initial catalytic activity for BPA removal after 8 consecutive batch cycles. This efficient method for preparing immobilized laccase can also be further developed and improved to acquire green biocatalysts for removing persistent organic pollutants in wastewater.

Highly sensitive determination of endocrine disrupting chemicals in foodstuffs through magnetic solid-phase extraction followed by high-performance liquid chromatography-tandem mass spectrometry.

BACKGROUND: Endocrine disrupting chemicals (EDCs), proved to be potential carcinogenic threats to human health, have received great concerns in food field. It was essential to develop effective methods to detect EDCs in food samples. The present study proposed an efficient method to determine trace EDCs including estrone (E1), 17ß-estradiol (E2), estriol (E3) and bisphenol A (BPA) based on magnetic solid-phase extraction (MSPE) coupled high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in meat samples. RESULTS: Fe3 O4 @COF(TpBD)/TiO2 nanocomposites were synthesized via functionalization of magnetic covalent organic frameworks (COFs) with titanium dioxide (TiO2 ) nanoparticles, and used as absorbents of MSPE to enrich EDCs. The efficient EDCs enrichment relies on π-π stacking interaction, hydrogen bonding, and the interaction between titanium ions (IV, Ti4+ ) and hydroxyl groups in EDCs, which improves the selectivity and sensitivity. Under the optimized conditions, target EDCs were rapidly extracted through MSPE with 5 min. Combining Fe3 O4 @COF(TpBD)/TiO2 based MSPE and HPLC-MS/MS to determine EDCs, good linearities were observed with correlation coefficient (R2 ) ≥ 0.9989. The limits of detection (LODs) and limits of quantification (LOQs) were 0.13-0.41 µg kg-1 and 0.66-1.49 µg kg-1 , respectively. Moreover, the proposed method was successfully applied to real samples analysis. CONCLUSIONS: The established MSPE-HPLC-MS/MS method was successfully applied to determine EDCs in meat samples with rapidness, improved selectivity and sensitivity. It shows great prospects for EDCs detection in other complicated matrices. © 2020 Society of Chemical Industry.

Potential use of two aryl sulfotransferase cell-surface display systems to detoxify the endocrine disruptor bisphenol A.

Bisphenol A (BPA) is one of the most common toxic endocrine disruptors in the environment. A fast, efficient and environmental-friendly method for BPA detoxification is urgently needed. In this study, we show that the enzymatic transformation of BPA into a non-estrogenic BPA sulfate can be performed by the aryl sulfotransferase (ASTB) from Desulfitobacterium hafniense. We developed and compared two Escherichia coli ASTB cell-surface displaying systems using the outer membrane porin F (OprF) and the lipoprotein outer membrane A (Lpp-OmpA) as carriers. The surface localization of both fusion proteins was confirmed by Western blot and flow cytometry analysis as well as the enzymatic activity assay of the outer membrane fractions. Unfortunately, Lpp-OmpA-ASTB cells had an adverse effect on cell growth. In contrast, the OprF-ASTB cell biocatalyst was stable, expressing 70% of enzyme activity for 7 days. It also efficiently sulfated 90% of 5 mM BPA (1 mg/mL) in wastewater within 6 h.

We are what we eat: Regulatory gaps in the United States that put our health at risk.

The American diet has changed dramatically since 1958, when Congress gave the United States Food and Drug Administration (FDA) the authority to ensure the safety of chemicals in food. Since then, thousands of chemicals have entered the food system. Yet their long-term, chronic effects have been woefully understudied, their health risks inadequately assessed. The FDA has been sluggish in considering scientific knowledge about the impact of exposures-particularly at low levels and during susceptible developmental stages. The agency's failure to adequately account for the risks of perchlorate-a well-characterized endocrine-disrupting chemical-to vulnerable populations is representative of systemic problems plaguing the regulation of chemicals in food. Today, we are faced with a regulatory system that, weakened by decades of limited resources, has fallen short of fully enforcing its mandates. The FDA's inability to effectively manage the safety of hundreds of chemicals is putting our children's health at risk.

Synthesis of magnetic metal organic framework/covalent organic framework hybrid materials as adsorbents for magnetic solid-phase extraction of four endocrine-disrupting chemicals from milk samples.

RATIONALE: Endocrine-disrupting chemicals (EDCs), widespread and easily ingested through the simple food chain, have been suggested to pose potential carcinogenic threats to human health. Considering food safety and public health, it is urgent to establish a sensitive and effective method to enrich and determine EDCs in food samples. METHODS: Novel hybrid nanocomposites Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti) were synthesized through the formation of amide bonds. The as-prepared Fe3 O4 were innovatively encapsulated with 4-aminobenzoic acid functionalized COF(A-TpBD) to generate bare carboxyl (-COOH), which formed amide bonds with the NH2 -MIL-125(Ti), generating well-defined and hierarchical hybrid materials. The Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti) materials were used as the adsorbents for magnetic solid-phase extraction (MSPE) coupled with high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) to enrich and determine EDCs (E1, E2, E3 and BPA) from milk samples. RESULTS: Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti) exhibited improved adsorption efficiency and selectivity based on π-π stacking interaction, hydrogen bonding, electrostatic interaction, and the interaction between the hydroxyl group in EDCs and titanium ions (IV, [Ti]4+ ). Under the optimized conditions, Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti)-based MSPE coupled with HPLC/MS/MS showed good linearity with correlation coefficient (R2 ) ≥0.9983 and high sensitivity with limits of detection (LODs) in the range of 0.37-0.85 µg/L. Moreover, the developed method was successfully employed to detect EDCs in milk samples. CONCLUSIONS: Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti) possess good adsorption capability and selectivity for EDCs. In addition, the proposed MSPE-HPLC/MS/MS method based on Fe3 O4 @A-TpBD@NH2 -MIL-125(Ti) is effective and sensitive for the determination of EDCs in real samples, which can be used as a robust alternative method to monitor EDCs in complex matrices.

Effects of effluent organic matters on endocrine disrupting chemical removal by ultrafiltration and ozonation in synthetic secondary effluent.

Endocrine disrupting chemicals (EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration (UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters (EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt (NaAH), bovine serum albumin (BSA) and sodium alginate (NaAg); and the five EDCs were estrone, 17ß-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH>BSA>NaAg. The ultraviolet absorbance at 280nm (UVA280) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA280 exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH, BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg>NaAH>BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH>BSA>NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.

White rot fungi and advanced combined biotechnology with nanomaterials: promising tools for endocrine-disrupting compounds biotransformation.

Endocrine-disrupting compounds (EDCs) can interfere with endocrine systems and bio-accumulate through the food chain and even decrease biodiversity in contaminated areas. This review discusses a critical overview of recent research progress in the biotransformation of EDCs (including polychlorinated biphenyl and nonylphenol, and suspected EDCs such as heavy metals and sulfonamide antibiotics) by white rot fungi (WRF) based on techniques with an emphasis on summarizing and analyzing fungal molecular, metabolic and genetic mechanisms. Not only intracellular metabolism which seems to perform essential roles in the ability of WRF to transform EDCs, but also advanced applications are deeply discussed. This review mainly reveals the removal pathway of heavy metal and antibiotic pollutants because the single pollution almost did not exist in a real environment while the combined pollution has become more serious and close to people's life. The trends in WRF technology and its related advanced applications which use the combined technology, including biocatalysis of WRF and adsorption of nanomaterials, to degrade EDCs have also been introduced. Furthermore, challenges and future research needs EDCs biotransformation by WRF are also discussed. This research, referring to metabolic mechanisms and the combined technology of WRF with nanomaterials, undoubtedly contributes to the applications of biotechnology. This review will be of great benefit to an understanding of the trends in biotechnology for the removal of EDCs.

Extraction and detection of bisphenol A in human serum and urine by aptamer-functionalized magnetic nanoparticles.

A new type of magnetic nanoparticles (MNPs), as the absorbents of bisphenol A (BPA), was prepared by functionalization of Fe3O4@SiO2 with BPA-specific aptamer in this work. ssDNA aptamer was immobilized on the Fe3O4@SiO2 surface through biotin-avidin interactions, playing a role of the specific probe for BPA. The resultant materials (Apt-MNPs) exhibited outstanding magnetic responsibility and can be separated efficiently by the magnetic field. Experimental results also showed that Apt-MNPs had large adsorption capacity and high competitive selectivity for the targeted compound BPA. Furthermore, Apt-MNPs were adopted as the specific absorbents to extract and enrich BPA from human serum and urine samples. Therefore, an efficient detection method of BPA was developed in combination with high-performance liquid chromatography (HPLC). The linearity of the method was over a range of 5-10,000 ng mL-1 with a correlation coefficient of 0.99997, and the limit of detections (LODs) for serum and urine were 2.0 and 1.0 ng mL-1, respectively. The recoveries of BPA in the spiked human serum and urine samples were 90.8 ± 7.3% (RSD) and 92.3 ± 1.5%, respectively. Our results demonstrated that Apt-MNPs were high-performance adsorbents for extracting and enriching BPA, resulting in fast and efficient detection of BPA in serum and urine samples. Graphical abstract Aptamer-MNPs were effective for BPA separation from serum and urine.

Environmental mixture with estrogenic activity increases Hsd3b1 expression through estrogen receptors in immature rat granulosa cells.

Humans are exposed not only to single endocrine disruptors, but also to chemical mixtures that can adversely affect their reproductive health. Steroidogenesis in reproductive tissues is emerging as the key target of endocrine disruptor action. Here, we analyzed the effect of environmental chemical mixtures with estrogenic activity on steroidogenic processes in immature rat granulosa cells and whether the observed steroidogenic effects were mediated through estrogen receptors. Extracts from untreated wastewater were prepared by solid-phase extraction and silica gel fractionation. ER-CALUX assay showed that the polar fractions of wastewater exerted different levels of estrogenic activity. Exposure of immature granulosa cells to the polar fraction exerting 9 ng of 17ß-estradiol equivalents per liter of water of estrogenic activity increased mRNA expression of the key enzymes of progesterone biosynthetic pathway Star and Hsd3b1, but did not alter the level of Cyp19a1 and Lhr. Addition of estrogen receptor inhibitor ICI 182 780 prevented the estrogenic mixture-induced increase in Hsd3b1, but not Star mRNA level in immature granulosa cells. These results indicate that the environmental chemical mixtures with estrogenic activity exert endocrine disrupting effects by augmenting the progesterone biosynthetic pathway in immature rat granulosa cells, which is an effect achieved in part through activation of the estrogen receptors.

In silico binding of 4,4'-bisphenols predicts in vitro estrogenic and antiandrogenic activity.

Bisphenols, anthropogenic pollutants, leach from consumer products and have potential to be ingested and are excreted in waste. The endocrine disrupting effects of highly manufactured bisphenols (BPA, BPS, and BPF) are known, however the activities of others are not. Here, the estrogenic and androgenic activities of a series of 4,4'-bisphenols that vary at the inter-connecting bisphenol bridge were determined (BPA, BPB, BPBP, BPC2, BPE, BPF, BPS, and BPZ) and compared to in silico binding to estrogen receptor-alpha and the androgen receptor. Bioassay results showed the order of estrogenicity (BPC2 (strongest) > BPBP > BPB > BPZ > BPE > BPF > BPA > BPS, r2 = 0.995) and anti-androgenicity (BPC2 (strongest) > BPE, BPB, BPA, BPF, and BPS, r2 = 0.996) correlated to nuclear receptor binding affinities. Like testosterone and the anti-androgen hydroxyflutamide, bisphenol fit in the ligand-binding domain through hydrogen-bonding at residues Thr877 and Asn705, but also interacted at either Cys784/Ser778 or Gln711 through the other phenol ring. This suggests the 4,4'-bisphenols, like hydroxyflutamide, are androgen receptor antagonists. Hydrogen-bond trends between ERα and the 4,4'-bisphenols were limited to residue Glu353, which interacted with the -OH of one phenol and the -OH of the A ring of 17ß-estradiol; hydrogen-bonding varied at the -OH of ring D of 17ß-estradiol and the second phenol -OH group. While both estrogen and androgen bioassays correlated to in silico results, conservation of hydrogen-bonding residues in the androgen receptor provides a convincing picture of direct antagonist binding by 4,4'-bisphenols.

"Not tonight zebrafish": the effects of Ruta graveolens on reproduction.

CONTEXT: There is growing interest in the pharmacological evaluation of Rue due to its potential to treat a variety of clinical diseases. The plant seems to present potent endocrine disrupting effects, and its excretion and disposal are not a concern. OBJECTIVE: The effects of Ruta graveolens L. (Rutaceae) ethanol extract (RE) on reproductive behaviour, fertility, and steroid and thyroid hormone levels in zebrafish were investigated. MATERIAL AND METHODS: We exposed subjects to varying concentrations of RE, and one-tenth the LC50 concentration (2.37 ppm) was established as the sublethal dose. After 2 weeks exposure, reproductive behaviour, cumulative number of eggs laid, percentage of fertilized eggs, and whole body steroid and thyroid hormones were measured. RESULTS: Reproductive association behaviour did not differ between control and RE-exposed animals, but spawning attempts were reduced in RE exposed animals. Cumulative egg production between days 9 to 14, RE exposed fish laid 672 eggs while control fish laid 1242 eggs. Also, percentage of fertilized eggs was higher for the control than for the RE exposed fish. Estradiol-17ß (E2) levels were reduced in females exposed to RE and testosterone (T) was statistically lower in both males and females treated with RE. Furthermore, thyroid hormones (T3 and T4) declined in fish treated with RE. CONCLUSION: RE has endocrine disrupting potential in fish, which has important implications for studying the effects of unintentional pharmaceutical exposure. Moreover, the results demonstrate that drug exposure may affect more than just the overall level of behaviour, emphasizing the relevance of examining the effects of individual exposure. We reinforce the use of zebrafish as a model organism in physiology and behaviour, and raise concerns about the toxic effects of RE in non-target organisms such as aquatic vertebrates, which may ultimately affect human health.

Dispersive liquid-liquid microextraction of phenolic compounds from vegetable oils using a magnetic ionic liquid.

A novel method was developed for the determination of two endocrine-disrupting chemicals, bisphenol A and 4-nonylphenol, in vegetable oil by dispersive liquid-liquid microextraction followed by ultra high performance liquid chromatography with tandem mass spectrometry. Using a magnetic liquid as the microextraction solvent, several key parameters were optimized, including the type and volume of the magnetic liquid, extraction time, amount of dispersant, and the type of reverse extractant. The detection limits for bisphenol A and 4-nonylphenol were 0.1 and 0.06 µg/kg, respectively. The recoveries were 70.4-112.3%, and the relative standard deviations were less than 4.2%. The method is simple for the extraction of bisphenol A and 4-nonylphenol from vegetable oil and suitable for routine analysis.

Magnetic porous carbon derived from Co-doped metal-organic frameworks for the magnetic solid-phase extraction of endocrine disrupting chemicals.

Metal-organic frameworks-5 (MOF-5) was explored as a template to prepare porous carbon due to its high surface area, large pore volume, and permanent nanoscale porosity. Magnetic porous carbon, Co@MOF-5-C, was fabricated by the one-step direct carbonization of Co-doped MOF-5. After carbonization, the magnetic cobalt nanoparticles are well dispersed in the porous carbon matrix, and Co@MOF-5-C displays strong magnetism (with the saturation magnetization intensity of 70.17emu/g), high-specific surface area, and large pore volume. To evaluate its extraction performance, the Co@MOF-5-C was applied as an adsorbent for the magnetic solid-phase extraction of endocrine disrupting chemicals, followed by their analysis with high-performance liquid chromatography. The developed method exhibits a good linear response in the range of 0.5-100 ng/mL for pond water and 1.0-100 ng/mL for juice samples. The limits of detection (S/N = 3) for the analytes were in the range of 0.1-0.2 ng/mL.

Photochemical Elimination of Endocrine Disrupting Chemical (EDC) by ZnO Nanoparticles, Synthesized by Gel Combustion.

Zinc Oxide (ZnO) nanoparticles prepared by gel combustion synthesis using cassava pearl starch have been characterized by various microscopy and spectroscopy techniques. The particle size averaged around 45 nm, revealed zincite structure, hexagonal, agglomerated morphology and possessed an excellent photocatalytic activity in sunlight. Contrary to the existing literature survey, this photocatalyst possessed a band gap of 2.7 eV, causing an extended absorption towards broader range of the solar spectrum, thus making it an excellent visible light-activated photocatalyst. Photocatalytic activity was investigated on one of the highly resistant, most-focused endocrine disrupting chemical (EDC) benzophenone-3 (BP-3), which is used in personnel care products. The observations reveal a near complete photooxidative degradation of BP-3. A reaction mechanism for the photooxidative pathway was proposed based on the isolated intermediates.

Online preconcentration by electrokinetic supercharging for separation of endocrine disrupting chemical and phenolic pollutants in water samples.

Online preconcentration using electrokinetic supercharging (EKS) was proposed to enhance the sensitivity of separation for endocrine disrupting chemical (methylparaben (MP)) and phenolic pollutants (2-nitrophenol (NP) and 4-chlorophenol (CP)) in water sample. Important EKS and separation conditions such as the concentration of BGE; the choice of terminating electrolyte (TE); and the injection time of leading electrolyte (LE), sample, and TE were optimized. The optimum EKS-CE conditions were as follows: BGE comprising of 12 mM sodium tetraborate pH 10.1, 100 mM sodium chloride as LE hydrodynamically injected at 50 mbar for 30 s, electrokinetic injection (EKI) of sample at -3 kV for 200 s, and 100 mM CHES as TE hydrodynamically injected at 50 mbar for 40 s. The separation was conducted at negative polarity mode and UV detection at 214 nm. Under these conditions, the sensitivity of analytes was enhanced from 100- to 737-fold as compared to normal CZE with hydrodynamic injection, giving LOD of 4.89, 5.29, and 53 µg/L for MP, NP and CP, respectively. The LODs were adequate for the analysis of NP and CP in environmental water sample having concentration at or lower than their maximum admissible concentration limit (240 and 2000 µg/L for NP and CP). The LOD of MP can be suitable for the analysis of MP exists at mid-microgram per liter level, even though the LOD was slightly higher than the concentration usually found in water samples (from ng/L to 1 µg/L). The method repeatabilities (%RSD) were in the range of 1.07-2.39% (migration time) and 8.28-14.0% (peak area).

Bioaugmentation Mitigates the Impact of Estrogen on Coliform-Grazing Protozoa in Slow Sand Filters.

Exposure to endocrine-disrupting chemicals (EDCs), such as estrogens, is a growing issue for human and animal health as they have been shown to cause reproductive and developmental abnormalities in wildlife and plants and have been linked to male infertility disorders in humans. Intensive farming and weather events, such as storms, flash flooding, and landslides, contribute estrogen to waterways used to supply drinking water. This paper explores the impact of estrogen exposure on the performance of slow sand filters (SSFs) used for water treatment. The feasibility and efficacy of SSF bioaugmentation with estrogen-degrading bacteria was also investigated, to determine whether removal of natural estrogens (estrone, estradiol, and estriol) and overall SSF performance for drinking water treatment could be improved. Strains for SSF augmentation were isolated from full-scale, municipal SSFs so as to optimize survival in the laboratory-scale SSFs used. Concentrations of the natural estrogens, determined by gas chromatography coupled with mass spectrometry (GC-MS), revealed augmented SSFs reduced the overall estrogenic potency of the supplied water by 25% on average and removed significantly more estrone and estradiol than nonaugmented filters. A negative correlation was found between coliform removal and estrogen concentration in nonaugmented filters. This was due to the toxic inhibition of protozoa, indicating that high estrogen concentrations can have functional implications for SSFs (such as impairing coliform removal). Consequently, we suggest that high estrogen concentrations could impact significantly on water quality production and, in particular, on pathogen removal in biological water filters.

Enantioselective separation of defined endocrine-disrupting nonylphenol isomers.

Nonylphenol is in the focus of worldwide endocrine-disrupter research and accounted for as a priority hazardous substance of the Water Framework Directive of the European Union. Technical nonylphenol consists of a very complex mixture of isomers and enantiomers. As estrogenic effect and degradation behavior in environmental processes of single nonylphenols are heavily dependent on the structure of the nonyl side chain, it is absolutely necessary to consider the nonylphenol problem from an isomer and enantiomer-specific viewpoint. In this study, an enantiomer-specific separation of eight defined synthesized nonylphenol isomers by five different special chiral cyclodextrin columns was performed underivatized and after methylation, silylation, and acylation. This work demonstrates that three columns out of the investigated five show an excellent separation behavior for the studied different nonylphenol isomers and can be used for the enantiomer-specific determination of nonylphenols in food, other biological matrices, and environmental samples in the future. Graphical abstract Enantiomeric pair of 4-NP170 (4-[1-ethyl-1,3,3-trimethylbutyl]phenol).

Recent advances and progress in the detection of bisphenol A.

Bisphenol A (BPA) is an important industrial chemical used as a plasticizer in polycarbonate and epoxy resins in the plastic and paper industries. Because of its estrogenic properties, BPA has attracted increasing attention from many researchers. This review focuses primarily on analytical methods for BPA detection that have emerged in recent years. We present and discuss the advantages and disadvantages of sample preparation techniques (e.g., solvent extraction, solid-phase extraction, molecularly imprinted polymer solid-phase extraction, and micro-extraction techniques) and analytical methods (e.g., liquid chromatography, liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry, capillary electrophoresis, immunoassay, and several novel sensors). We also discuss expected future developments for the detection of BPA. Graphical Abstract This review focuses primarily on the recent development in the detection of bisphenol A including sample pre-treatment and analytical methods.

Polypyrrole-coated alginate/magnetite nanoparticles composite sorbent for the extraction of endocrine-disrupting compounds.

Magnetite nanoparticles incorporated into alginate beads and coated with a polypyrrole adsorbent were prepared (polypyrrole/Fe3 O4 /alginate bead) and used as an effective magnetic solid-phase extraction sorbent for the extraction and enrichment of endocrine-disrupting compounds (estriol, ß-estradiol and bisphenol A) in water samples. The determination of the extracted endocrine-disrupting compounds was performed using high-performance liquid chromatography with a fluorescence detector. The effect of various parameters on the extraction efficiency of endocrine disrupting compounds were investigated and optimized including the type and amount of sorbent, sample pH, extraction time, stirring speed, and desorption conditions. Under optimum conditions, the calibration curves were linear in the concentration range of 0.5-100.0 µg/L, and the limit of detection was 0.5 µg/L. The developed method showed a high extraction efficiency, the recoveries were in the range of 90.5 ± 4.1 to 98.2 ± 5.5%. The developed sorbent was easy to prepare, was cost-effective, robust, and provided a good reproducibility (RSDs < 5%), and could be reused 16 times. The developed method was successfully applied for the determination of endocrine-disrupting compounds in water samples.