Vesicular coacervative extraction of bisphenols and their diglycidyl ethers from sewage and river water

Exploring BPA alternatives - Environmental levels and toxicity review

Bisphenol A alternatives are manufactured as potentially less harmful substitutes of bisphenol A (BPA) that offer similar functionality. These alternatives are already in the market, entering the environment and thus raising ecological concerns. However, it can be expected that levels of BPA alternatives will dominate in the future, they are limited information on their environmental safety. The EU PARC project highlights BPA alternatives as priority chemicals and consolidates information on BPA alternatives, with a focus on environmental relevance and on the identification of the research gaps. The review highlighted aspects and future perspectives. In brief, an extension of environmental monitoring is crucial, extending it to cover BPA alternatives to track their levels and facilitate the timely implementation of mitigation measures. The biological activity has been studied for BPA alternatives, but in a non-systematic way and prioritized a limited number of chemicals. For several BPA alternatives, the data has already provided substantial evidence regarding their potential harm to the environment. We stress the importance of conducting more comprehensive assessments that go beyond the traditional reproductive studies and focus on overlooked relevant endpoints. Future research should also consider mixture effects, realistic environmental concentrations, and the long-term consequences on biota and ecosystems.

Supramolecular solvent extraction and ambient mass spectrometry for the determination of organic contaminants in food packaging material

A rapid method based on a fast sample treatment with supramolecular solvents (SUPRASs) and ambient mass spectrometry (AMS) analysis was developed for the screening and quantification of organic contaminants in food packaging materials (FCMs). The suitability of SUPRASs made up of medium chain alcohols in ethanol:water mixtures was investigated, given their low toxicity, proven capacity for multi-residue analysis (since they provide a wide variety of interactions and multiple binding sites) and restricted access properties for simultaneous sample extraction and clean-up. Two families of emerging organic pollutants, bisphenols and organophosphate flame retardants, were targeted as representative compounds. The methodology was applied to 40 FCMs. Target compounds were quantitated using ASAP (atmospheric solids analysis probe)-low resolution MS and a broad-spectrum screening of contaminants was performed through spectral library search using direct injection probe (DIP) and high resolution MS (HRMS). The results showed the ubiquity of bisphenols and of some flame retardants, as well as the presence of other additives and unknown compounds in about half of the analyzed samples, which highlight the complex composition of FCMs and the possible associated health risks.

USAEME-GC/MS Method for Easy and Sensitive Determination of Nine Bisphenol Analogues in Water and Wastewater

A new, simple and sensitive method for isolating nine compounds from the bisphenol group (analogues: A, B, C, E, F, G, Cl₂, Z, AP) based on one-step liquid-liquid microextraction with in situ acylation followed by gas chromatography-mass spectrometry was developed and validated using influent and effluent wastewaters. The chemometric approach based on the Taguchi method was used to optimize the main conditions of simultaneous extraction and derivatization. The recoveries of the proposed procedure ranged from 85 to 122%, and the repeatability expressed by the coefficient of variation did not exceed 8%. The method's limits of detection were in the range of 0.4-64 ng/L, and the method's limits of quantification ranged from 1.3 to 194 ng/L. The developed method was used to determine the presence of the tested compounds in wastewater from a municipal wastewater treatment plant located in northeastern Poland. From this sample, eight analytes were detected. Concentrations of bisphenol A of 400 ng/L in influent and 100 ng/L in effluent were recorded, whereas other bisphenols reached 67 and 50 ng/L for influent and effluent, respectively. The removal efficiency of bisphenol analogues in the tested wastewater treatment plant ranged from 7 to approximately 88%.

Supramolecular solvent-based microextraction probe for fast detection of bisphenols by ambient mass spectrometry

In this study, we investigated for the first time the suitability of supramolecular solvent (SUPRAS)-based microextraction probe for the development of generic and fast sample treatment prior to qualitative analysis by ambient mass spectrometry (AMS) based on ASAP (atmospheric solids analysis probe). SUPRAS are nanostructured liquids formed by the self-assembly of amphiphilic aggregates with multiple binding sites and microenvironments of different polarity for the efficient extraction of multiple compounds. Different types of SUPRAS were evaluated as a simple and single step sample treatment for ASAP. The method was applied to the screening of bisphenol A and structural analogues in thermal paper. Optimal results were achieved with SUPRAS synthesized with 1-decanol in mixtures of ethanol:water. SUPRAS (1.1-2 μL) were loaded onto glass probes and placed in contact with samples for 10 s before ASAP analysis. AMS signal peaks (width: 0.2-0.5 min) were easily integrated and normalized with internal standards (RSD: 2-25%). The method was applied to 62 samples of thermal paper. BPA and BPS were the most widely used, this highlighting the progressive industrial replacement of BPA by BPS.

Supramolecular solvent-based microextraction of emerging bisphenol A replacements (colour developers) in indoor dust from public environments

Bisphenol A (BPA) is present in a wide variety of materials and it is a well-known endocrine disruptor that is widespread in indoor and outdoor environments. For this reason, industry has introduced a variety of replacements, such as Bisphenol S (BPS) or Bisphenol F (BPF), and other less known structural analogs, such as BPS-MAE, D-8 or TGSA. These emerging potential contaminants have been identified in thermal paper products, according to recent studies, but their potential toxic effects and their migration into the environment remain unclear. In this study, we report for the first time the presence of emerging BPA replacements in indoor dust from public environments (shops, restaurants, etc.). For this purpose, we optimized a novel supramolecular solvent (SUPRAS)-based microextraction method. SUPRAS are multi-target solvents made up of self-assembled amphiphiles. They offer multiple extraction interactions (dispersion, polar, hydrophobic, etc.) and they constitute excellent candidates to develop generic and fast sample treatment procedures at low cost. By this method, emerging BPA replacements (BPS-MAE, D-8 and TGSA) were detected in dust at median concentrations in the range 6-22 ng g^-1 (around ten times lower than BPS) with detection frequencies in the range 50-90%. These results constitute a first insight into the migration of emerging BPA replacements into the environment via indoor dust, which is a common route of human exposure to contaminants.

Multifunctional vesicular coacervates as engineered supramolecular solvents for wastewater treatment

In this study, multifunctional supramolecular solvents (SUPRASs) able to simultaneously extract ionic, polar and hydrophobic organic compounds from wastewater have been developed. SUPRASs were synthesized in aqueous solutions containing mixtures of carboxylic acids and carboxylates that underwent spontaneous self-assembly and coacervation under the addition of tetraalkylammonium ions. These SUPRAS consisted of coacervate droplets made up of large unilamellar vesicular aggregates bridged by tetraalkylammonium ions. Both, the high kinetic stability of vesicles and their strong interaction with tetraalkylammonium ions through different bonds working cooperatively, made supramolecular nanostructures in the SUPRAS chemically stable, which minimized the presence of solvent residues in the treated water. The suitability of the synthesized SUPRASs to behave as multifunctional extractants in water treatment was investigated by their application to the removal of anionic, cationic and ionizable dyes and PAHs. All the variables affecting the extraction process were optimized (i.e. chain length of the tetraalkylammonium ion, fractional SUPRAS phase volume, pH, ionic strength, pollutant concentration and stirring time/rate). All the pollutants selected were efficiently removed at room temperature and a fractional SUPRAS phase volume of 0.01. Applicability of the SUPRAS-based treatment to the efficient removal of dyes in textile effluents and benzo(a)pyrene in tap water was proved. Overall, the low cost, easy synthesis and high removal efficiency of these engineered SUPRASs make them highly promising for application in comprehensive wastewater treatments.

The occurrence of bisphenol plasticizers in paired dust and urine samples and its association with oxidative stress

Bisphenol A diglycidy ether (BADGE) and its derivatives are epoxy resins and widely used as emerging plasticizers in food packages and material coating. Though known as endocrine disruptors, little information is available on their occurrence, exposure routes and toxicity. Besides, the analysis of BADGE and its derivatives has always been a challenge due to their reactive chemical properties and the background contamination. Therefore, we firstly developed a novel water-free method to analyze BADGE and its derivatives in dust samples together with other two typical plasticizers bisphenol A (BPA) and bisphenol S (BPS). In order to investigate the levels in paired dust and urine samples, 33 paired samples were collected from Singapore. In both dust and urine samples, the predominant compounds were BPA, BADGE-2H₂O and BPS. A significantly positive correlation of BPA levels in paired dust and urine samples was observed in this small-scale study. To tentatively explore the human health effect from exposure to these bisphenol plasticizers, we assessed the correlation between the urinary concentrations of these compounds and oxo-2'-deoxyguanosine (8-OHdG), an oxidative stress biomarker. The result showed that 8-OHdG levels in urine samples was positively correlated with urinary BPA level and body mass index (BMI), suggesting that elevated oxidative stress might be associated with BPA exposure and obesity. In the future, a larger scale study is warranted due to the limited sample size in this study.

Bisphenol A and replacements in thermal paper: A review

Thermal paper contains potentially toxic compounds such as bisphenol A (BPA), which is used as a color developer. BPA has been reported in thermal paper in concentrations up to 42,600 μg g^-1. The exposure to BPA via dermal transfer has been recently discussed as a significant contribution to the overall human exposure and the estimated daily intake (EDI) has been reported up to 218 μg d^-1. BPA has been also detected in recycled paper with concentrations up to 46 μg g^-1. Due to the fact that BPA is a known endocrine disruptor and migrates from materials, regulatory restrictions have been established to prevent risks for the human health. As a consequence, structural analogues, such as bisphenol S (BPS) have been introduced into the market. Little is known about the presence and toxicity of these emerging replacements, and concern has risen about them. The present review gives an overview of the occurrence and levels of BPA and replacements in thermal paper. BPA is still the most common color developer found in thermal paper, followed by BPS. The analytical methods used for quantification of BPA and BPA replacements in paper products are also reviewed. BPA is transferred from thermal paper products to the finger pads upon handling it. Paper-skin transfer followed by penetration of BPA depends on conditions (e.g. greasiness of fingers and use of hand cream). It is, however, still debated whether thermal paper as a source for human exposure contributes significantly to the overall internal BPA exposure.

Spectroscopic and molecular modeling approaches to investigate the interaction of bisphenol A, bisphenol F and their diglycidyl ethers with PPARα

A fluorescence polarization (FP) assay for the simultaneous determination of bisphenol A (BPA), bisphenol F (BPF), bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) was developed. The method was based on the competition between bisphenols (BPs) and fluorescein-labeled dexamethasone derivative (Dex-fl) for mouse peroxisome proliferator-activated receptor α ligand binding domain (mPPARα-LBD). A recombinant soluble protein derivative mPPARα-LBD* was prepared, then in vitro binding of 4 BPs to mPPARα-LBD* was investigated. Fluorescence polarization assay showed that these compounds exhibited different binding potencies with mPPARα-LBD*. Additionally, molecular dynamics simulations were performed to further understand the mechanism of BPs binding affinity for mPPARα-LBD*. Docking results elucidated that the driving forces for the binding of BPs to mPPARα-LBD* were predominantly dependent on hydrophobic and hydrogen-bonding interactions. Comparison of the calculated binding energies vs. experimental binding affinities yielded a good correlation (R² = 0.7258). The proposed method has potential for multi-residue detection of BPA, BPF, BADGE, and BFDGE.

Assessment of risk to humans of bisphenol A in marine and freshwater fish from Pearl River Delta, China

Bisphenol A (BPA) is a high production-volume chemical used in the manufacture of a wide variety of consumer products. However it is also a ubiquitous contaminant that can interfere with endocrine systems of wildlife and humans. China is the "world factory" and the Pearl River Delta is the major manufacturing center and is consequently polluted. Concentrations of BPA in meats of marketable fish had not been previously reported for this region. In the study upon which we report here concentrations of BPA were determined in 20 common species of freshwater and marine fish, collected from markets in Hong Kong, SAR, China. A comprehensive analytical method based on SPE extraction and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was developed, validated and applied. The method limit of detection (LOD) and limit of quantification (LOQ) were 0.5 and 1.25 ng g(-1) dw, respectively. BPA was detected in 19 species of fish at concentrations, ranging from 0.5 to 2.0 ng g(-1) ww. Average daily BPA intake per person ranged from 1.1×10(2) ng d(-1) for marine fish and 2.2×10(2) ng d(-1) for freshwater fish. Concentrations of BPA in fish from Hong Kong markets unlikely would be causing adverse population-level effects in humans.