Bisphenol A In Samples Research Articles

Biomonitoring of bisphenol A (BPA) and bisphenol analogues in human milk from South Africa and Canada using a modified QuEChERS extraction method

A sensitive modified QuEChERS extraction method was developed to assess the levels of free and conjugated bisphenols (BPs) in human milk collected between 2018 and 2019 from two regions of South Africa (the Limpopo Province Vhembe district, n = 194; Pretoria, n = 193) and Canada (Montreal, n = 207). Total BPA (free and conjugated) and BPS were the predominant bisphenols detected in samples from Vhembe and Pretoria, whereas total BPS was the predominant bisphenol detected in Montreal samples. The levels of total BPA in samples from Vhembe and Pretoria ranged between < MDL-18.61 and <MDL-19.38 ng/mL, with medians of 1.03 ng/mL and 0.69 ng/mL and detection frequencies of 73% and 68%, respectively. The speciation analysis of BPA revealed a predominantly conjugated form in South African samples. In contrast, total BPA was detected in only one milk sample from Montreal. Total BPS levels were lower than BPA in South Africa, with detection frequencies of 57% and 21% in Vhembe and Pretoria, respectively. In contrast, total BPS was the major BP detected (42%) in Montreal (up to 4.42 ng/mL). BPAF was found exclusively in South Africa, with detection frequencies for total BPAF of 40% and 9% in Vhembe (<MDL-12.41 ng/mL) and Pretoria (<MDL-0.11 ng/mL), respectively. To our knowledge, this is one of the first studies to detect bisphenols in human milk from data-scarce countries such as South Africa and to highlight the notable disparities in the types and levels of bisphenols detected across two distinct countries (Canada and South Africa).

A novel ratiometric imprinted electrochemical sensing bisphenol A using MIP with alkenyl ferrocene as a functional monomer and COF-derived porous carbon as a sensitive element

Free radical polymerization is widely used for preparing molecularly imprinted polymers (MIPs) by copolymerizing alkenyl functional monomers and cross-linkers with the template molecules. However, these monomers based electrochemical sensors can only construct single-signal electrochemical sensors, making them vulnerable to various interferences. Therefore, this work aims to construct a ratiometric molecularly imprinted (RMI) electrochemical sensor by free radical polymerization. First, 3-butenoic acid (ferrocenyl) methyl ester (BA-Fc) as an alkenyl ferrocene was synthesized using hydroxymethylferrocene as a reactant. A new ferrocene-based molecularly imprinted polymer (Fc-MIP) was then synthesized by free radical polymerization with BA-Fc as functional monomer. To enhance the electrical conductivity of the covalent organic framework (COF), COF-derived porous carbon (COF-PC) was synthesized through pyrolysis. A RMI electrochemical sensor was then constructed to detect bisphenol A (BPA). For this construction, COF-PC and Fc-MIP served as the sensitive and selective elements, respectively. The oxidation peaks of BPA and Fc were utilized for the response and internal reference signals, respectively. This sensor displayed a linear ratiometric signal (IBPA/IFc) in response to BPA concentrations from 0.1 to 10 µM with detection limit of 0.03 µM. The relative standard deviation of the non-ratiometric and ratiometric sensors was 6.71% and 3.10%, respectively, demonstrating the advantage of the RMI sensor. This proposed sensor, exhibiting satisfactory reproducibility, sensitivity, and selectivity, was successfully applied in detecting BPA in samples of industrial wastewater, soil, and plastic bottles.

Trends of bisphenol A occurrence in canned food products from 2008–2020

It is known that the industry already abandoned the use of bisphenol A (BPA)-based epoxy resins as internal coatings for some canned food products (e.g. infant formula, soups). The presence of bisphenol A (BPA) in foods has also been extensively investigated, especially since late 2000. However, information on temporal trends of BPA occurrence in foods is very limited. It is not clear if BPA-based epoxy resins are still being used in internal coating for many other canned foods and if the overall exposure to BPA through consumption of canned foods has significantly decreased. As part of the Canadian total diet study (TDS) program, we have been analysing food samples for BPA since 2008. In this study, results of BPA in samples of different composite canned foods from 2008–2020 TDS were reported. Clear temporal trends were observed for canned fish and soups, with BPA levels being significantly reduced since 2014 for canned fish products and 2017 for canned soups. Temporal trends were not observed for canned evaporated milk, luncheon meats, and vegetables, with even the highest levels of BPA being detected in recent samples for evaporated milk (57 ng/g), luncheon meats (56 ng/g), and baked beans (103 ng/g). This seems to indicate that BPA-based epoxy resins are still being used in the internal coatings for these canned foods products. Thus, analysis of canned food samples for BPA should be continued for exposure assessment.

Facile and Sensitive Method for Detecting Bisphenol A UsingUbiquitous pH Meters

AbstractA sensitive and rapid method for the detection of bisphenol A (BPA) using general pH meters or pH paper was developed. Aptamer‐functionalized Fe3O4 magnetic nanoparticles (MNPs) were synthesized to capture BPA in samples, and gold NPs (AuNPs) were modified with acetylcholinesterase and the complementary strand of BPA aptamer. The specific detection of BPA was realized using the combination of BPA‐responsive, aptamer‐cross‐linked MNPs‐AuNPs complex. As the acetylcholine was hydrolyzed to choline and acetic acid, the pH of the solution decreased. The resulting pH change could be measured in real‐time using a pH meter. The sensitivity of detection of this assay was 5 pg/mL with the range of 0.01 to 1000 ng/mL. The pH change could be determined with the naked eye from the color change of a pH indicator strip. This sensor technology is promising and reliable for rapid, sensitive, and on‐site monitoring of BPA in water samples.

Migration of bisphenol A from epoxy-can malt drink under various storage conditions and evaluation of its health risk

ABSTRACT Bisphenol-A (BPA) is a notable endocrine disrupting chemical and a core raw material utilised in the manufacture of some food contact materials such as epoxy resin and polycarbonate (PC) plastics. The human health risk (HRI) associated with the migration of BPA into malt drinks packaged in epoxy-cans and stored under various conditions was investigated. Solid-phase extraction (SPE) was used to extract BPA, while analysis was performed with a high performance liquid chromatography coupled to an ultraviolet detector (HPLC-UV). The health risk index was used to assess the likelihood of developing chronic non-carcinogenic health risk among consumers of epoxy-can malt drink. Results showed BPA concentrations at 3.98 ± 0.05°C, 25.34 ± 0.70°C and 30.98 ± 0.27°C range from 0.0166 to 0.0300 μg L−1, 0.0188 to 0.0788 μg L−1 and 0.0217 to 0.2131 μg L−1 respectively. BPA levels in the samples did not exceed the European Union limit (50 μg kg−1). Enrichment levels of BPA in samples stored at 30.98 ± 0.27°C were highest, while that at 3.98 ± 0.05°C samples were the least. Initial migration rate of BPA at 3.98 ± 0.05°C and 25.34 ± 0.70°C decreased with increasing exposure duration, and later maintained a mildly constant rate at longer exposure duration. However, at 30.98 ± 0.27°C, BPA migration rates decreased initially with increase in exposure duration, and increased later at prolonged exposure. Although BPA concentrations showed no significant difference (p > 0.05) at the study’s storage conditions, a significant difference (p < 0.05) was observed in BPA migration rates. The computed chronic non-carcinogenic health risk for daily ingestion of malt drink contaminated with BPA by both adults and children was less than one indicating no probable adverse health effect from consumption of the malt drink.

Determination of bisphenol a migration from food packaging by dispersive liquid-liquid microextraction

In the current work, a rapid and simple dispersive liquid-liquid microextraction method (DLLME) was used to determine Bisphenol A (BPA). High performance liquid chromatography with the photodiode-array detector (HPLC-DAD) coupled DLLME method was employed to analyze BPA in food samples packaged including cans, paper boxes, and glass jars. The calibration curve was obtained to be in the linear range 0.009–25 ngg−1 with a correlation coefficient of R2 = 0.9981. The mean relative standard deviations (RSDs) was of 5.2% (n = 3). The limit of detection (LOD) and the limit of quantification (LOQ) of the method were obtained to be 0.001 ngg−1 and 0.08 ng.g−1, respectively.In sum, this method presents:•A rapid, simple and efficient modified DLLME method was used to measure BPA in packaged foods.•The advantages of this method were low detection limit, fast preparation, and high BPA recovery.•The DLLME-HPLC method consists of low detection limit and high recoveries to determine BPA in samples.•The results indicated that DLLME –HPLC-DAD was an applied method to measure BPA in food samples.

Determination of Very Low Concentration of Bisphenol A in Toys and Baby Pacifiers Using Dispersive Liquid-Liquid Microextraction by In Situ Ionic Liquid Formation and High-Performance Liquid Chromatography.

Bisphenol A (BPA) is a chemical compound used in the manufacturing of plastics and resins whose presence in the body in low concentrations can cause serious health problems. Due to this, there is a growing interest in the scientific community to develop analytical methods that allow quantifying trace concentrations of BPA in different types of samples. The determination of this compound in toys made of plastics that can be manipulated by children leads to an extra concern, because it is possible for BPA to enter the body by introducing these toys into the mouth. This work presents a novel procedure to the quickly and easily quantification of trace levels of BPA in samples of toys and pacifiers according to the current demanding regulations. The determination of very low levels of BPA was carried out by ionic liquid dispersive liquid–liquid microextraction (IL-DLLME) followed by high-performance liquid chromatography (HPLC). The formation in situ of the ionic liquid (IL) 1-octyl-3-methylimidazolium bis((trifluoromethane)sulfonyl)imide ([C8MIm] [NTf2]), was achieved by mixing 1-octyl-3-methylimidazolium chloride ([C8MIm]Cl) and lithium bis(trifluoromethanesulfonyl)imide ([NTf2]Li) aqueous solutions, reaching an instant dispersion whose cloud of microdrops allows the total extraction of BPA in the IL from aqueous solutions. After centrifugation, BPA concentration in the sedimented phase was determined by HPLC. The optimal experimental conditions for the microextraction and determination of BPA in the IL were studied. The total extraction was achieved at pH 4, heating the sample at 30 °C for 5 min, using 100 µL of IL precursor volume, and spinning after the formation of dispersion at 3000 rpm for 10 min. The enrichment factor (EF) and detection limit (LOD) reached with the procedure were 299 and 0.19 µg L−1, respectively. The relative standard deviation for ten replications at the 0.5 µg L−1 level was 5.2%. Recovery studies showed a mean value for BPA recovery percentage in the samples of 99%. Additionally, a hybrid model was applied to characterize the extraction kinetics. This simple, low cost and fast method simplifies traditional microextraction techniques, representing an outstanding alternative.

The Development of a Photothermal Immunochromatographic Lateral Flow Strip for Rapid and Sensitive Detection of Bisphenol A in Food Samples

A novel quantitative photothermal-sensing immunochromatographic assay (PT-ICA) with high sensitivity was developed for the detection of bisphenol A (BPA). Gold acid chloride trihydrate (HAuCl4·3H2O) was first reduced by citric acid trisodium salt (C6H5Na3O7) to form Au nanoparticles and adsorbed on the surface of black phosphorus nanosheets to form a black phosphorus-Au (BP-Au) complex. The antibody against BPA was then coupled to the BP-Au complex to form the black phosphorus-Au-antibody (BP-Au-Ab) photothermal probe for capturing BPA in samples. During the detection, the precoated antigen BPA-bovine serum albumin (BPA-BSA) on the T line and free BPA molecules in the sample would competitively bind to the limited BP-Au-Ab photothermal probes. After that, the exothermic process under an 808-nm laser was recorded using an infrared thermal imager, which represented the concentration of BPA in the samples. The PT-ICA demonstrated high sensitivity with a limit detection of 0.24 ng/mL, which was 6.25 times lower than that of the visual-ICA. In addition, the assays were highly specific, only minor cross-sensitivity occurred between BPA and 4-cumylphenol. The optimized assay was applied in the detection of BPA in different food samples with recoveries ranging from 75.91 to 119.59%. Finally, the PT-ICA was verified using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The results of the developed assay showed good agreement with that of the ELISA kit. The optimized PT-ICA required a shorter detection time (approximately 30 min) than the ELISA kit (approximately 2 h), which has potential applications in the detection field.

A novel high sensitivity UPLC-MS/MS method for the evaluation of bisphenol A leaching from dental materials

There is a growing necessity to acquire more profound knowledge on the quantity of eluates from resin-based dental materials, especially with regard to bisphenol A (BPA). The aim of the present study was to develop a highly sensitive method to characterize the short-term release of BPA in saliva with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), using an extraction step and additional derivatization of BPA with pyridine-3-sulfonyl chloride. Light-cured resin-based composites were incubated at 37 °C in 1 mL artificial saliva, which was refreshed daily for one week. The final protocol allows accurate quantification of very low levels of BPA in samples of artificial saliva (i.e. 1.10 pmol BPA/mL or 250 pg/mL). The daily BPA-release from dental composites, ranging from 1.10 to 7.46 pmol BPA/mL, was characterized over a period of 7 days. The highest total amount of BPA was released from Solitaire 2 (24.72 ± 2.86 pmol), followed by G-ænial Posterior (15.51 ± 0.88 pmol) and Filtek Supreme XTE (12.00 ± 1.31 pmol). In contrast, only trace amounts of BPA were released from Ceram.x Universal. This UPLC-MS/MS method might be used for clinical research focusing on the evaluation of the clinical relevance of BPA release from dental materials.

Quantifying bisphenol A in maternal and cord whole blood using isotope dilution liquid chromatography/tandem mass spectrometry and maternal characteristics associated with bisphenol A

Bisphenol A (BPA) is endocrine disrupting chemical that have been detected among general population. Exposure levels among pregnant women and their fetus are yet largely unknown among Japanese. We have developed a new method of measuring total BPA in whole blood samples by using isotopic dilution liquid chromatography-tandem mass spectrometry (ID-LC/MS/MS). For eliminating possible contaminations, we have used glass cartridge instead of polypropylene cartridge and successfully reduced background levels. Additionally gap retention technique was applied to improve sensitivity. We also confirmed no external contamination by measuring free BPA in the samples. The limit of quantification (LOQ) was 0.040 ng/ml. With this developed method, we determined total BPA concentrations of 59 maternal blood at delivery and 285 cord blood samples in prospective birth cohort study and investigated factors possibly related to total BPA levels. Total BPA levels ranged from below LOQ to 0.419 ng/ml and for maternal blood and from below LOQ to 0.217 ng/ml for cord blood, respectively. The geometric mean was 0.051 ng/ml for maternal blood and 0.046 ng/ml for cord blood, respectively. Although no correlation was observed between maternal and fetal blood levels of total BPA, our result suggested fetal exposure to BPA. We have found that younger mothers, frequent beef and pork consumption during pregnancy were positively associated with maternal total BPA levels. We confirmed in utero exposure to BPA, which highlights the importance of further studies of investing the effects of fetus BPA exposure on health outcomes.

Dispersive liquid–liquid microextraction followed by microwave-assisted silylation and gas chromatography-mass spectrometry analysis for simultaneous trace quantification of bisphenol A and 13 ultraviolet filters in wastewaters

A novel multi-residue gas chromatography-mass spectrometry (GC-MS) method was validated for the simultaneous determination of trace levels (ng/L) of 13 UV-filters and bisphenol A (BPA) in wastewater samples. It was based on dispersive liquid–liquid microextraction (DLMME) followed by rapid microwave-assisted silylation of the analytes. Several parameters of both extraction and derivatization steps such as type of extractive and dispersive solvents, solvent volumes, pH, salt addition, time and power of microwave were evaluated to achieve the highest yield and to attain the lowest detection limits. Optimized DLLME consisted in the formation of a cloudy solution promoted by the fast addition to the sample (10mL) of a mixture of tetrachloroethylene (50μL, extraction solvent) in acetone (1mL, dispersive solvent). The sedimented phase obtained was evaporated and further silylated under the irradiation of 600W microwave for 5min, being the derivatization yields similar to those obtained after a conventional heating process for 30min at 75°C. Limits of detection and quantification of the method using real samples were 2ng/L and 10ng/L, respectively. Mean extraction efficiency of 82% for three concentrations were achieved, supporting the accuracy of the method. Intra-day and inter-day repeatability of measurements (expressed as relative standard deviation) were lower than 22%. The method was successfully applied to the determination of UV-filters and BPA in samples collected from 15 wastewater treatment plants (WWTPs) in Portugal. Eight analytes were detected, among which 2-hydroxy-4-methoxybenzophenone, 2-ethylhexyl-4-(dimethylamino)benzoate, octocrylene, and BPA were consistently found in the three seasons of collection.

Determinação de bisfenol A em fórmulas infantis

Bisphenol A (BPA) is an endocrine disruptor and may present a serious toxicological and public health risk even at low doses. This problem has received widespread attention from the scientific community and food safety organizations. BPA is mainly used in the production of polycarbonate and epoxy resins, and can be transferred from plastic materials to food. The aim of the present study was determine the amount of BPA in samples of infant formula powder. The concentrations ranged from 0.2 to 10.2 µg/kg of sample, which is below the specific migration limit of BPA established by the European Union and Brazil. However, adverse effects on human health due to exposure to BPA are still possible at low doses. The scenario is complex, involves other forms of exposure and it still raises concern of authorities and entities involved in risk prevention and food safety.

Occurrence of Bisphenol A in soil and leachate of a municipal landfill: effect of the sample acidification

The main objective of present study was the quantitative analysis of bisphenol A (BPA) in soil and leachate of a municipal sanitary landfill. The influence of the solvent polarity and pH over the quantitative analysis of BPA in the leachate was also investigated. The soil samples were collected from closed cells and extracted by Soxhlet extraction with ethanol. The liquid samples, from row leachate from the same sanitary landfill were extracted by Solid Phase Extraction (SPE) with C-18 cartridges and ethanol. The organic extracts from liquid and solid samples were analyzed by Gas Chromatography with Flame Ionization Detector (GC/FID). For the soil and liquid samples the average concentrations of BPA were 21.30 (±0.61) mg kg-1 and 26.83 (±2.69) mg L-1, respectively. These results were far above the ones cited in the literature and are of special concern because BPA may disrupt the human endocrine system. The acidification allows the increase of 5% of the extraction efficiency. In this way, the acidification step is recommended for the quantification of BPA in samples where the concentration of this analyte is below 0.1%. In these cases the acidification step may avoid important loss of the analyte and improve the detection limit in the instrumental analysis. http://dx.doi.org/10.18226/23185279.v2iss1p10

One-Step Derivatization and Preconcentration Microextraction Technique for Determination of Bisphenol A in Beverage Samples by Gas Chromatography−Mass Spectrometry

A simple technique based on ultrasound-assisted emulsification microextraction in situ derivatization (USAEME-ISD) is proposed for the one-step derivatization, extraction, and preconcentration of bisphenol A (BPA) in beverage samples prior to gas chromatography-mass spectrometry (GC-MS) analysis. BPA was in situ derivatized with acetic anhydride and simultaneously extracted and preconcentrated by using USAEME. Variables affecting the extraction efficiency of BPA were evaluated. Under optimal experimental conditions, the detection limit (LOD) was 38 ng L(-1) with a relative standard deviation (RSD) value of 11.6%. The linear working range was 100-1250 ng L(-1), and the coefficient of estimation (r(2)) of the calibration curve was ≥0.9971. The robustness of the proposed methodology was probed by developing a recovery study at two concentrations (125 and 500 ng L(-1)) over different beverage samples. This study led to a satisfactory result achieving recoveries of ≥82%, which showed acceptable robustness for determination of nanograms per liter of BPA in samples of food safety interest.

Survey of bisphenol A in bottled water products in Canada

A method based on isotope dilution headspace solid-phase microextraction and gas chromatography/mass spectrometry was used to assess levels of bisphenol A (BPA) in 56 samples of bottled water products sold in Canada. Levels of BPA in samples of all 51 non-polycarbonate (PC) bottled water products were lower than the method detection limit (0.50 µg l–1). Levels of BPA in most bottled water products in PC carboys were low, ranging from <0.50 to 1.4 µg l–1 with an average of 0.75 µg l–1. However, BPA was detected at levels of 8.8 and 6.5 µg l–1 in two bottles of the bottled water products in PC carboys from the same product analysed over a 5-week period, likely due to accidental or careless exposure of the products to heat (e.g. under the sun) during storage and/or transportation for extended periods of time.

QUANTITATION OF BISPHENOL A AND BISPHENOL A GLUCURONIDE IN BIOLOGICAL SAMPLES BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY

Bisphenol A (BPA) is a weak estrogen. Pharmacokinetic studies of BPA have demonstrated a rapid and extensive metabolism of BPA to the nonestrogenic BPA-monoglucuronide (BPA-gluc). Some investigators have reported that BPA was found at parts per billion concentrations in the tissues or urine of humans without known exposure to BPA. This work developed a rapid and sensitive method for the determination of BPA and BPA-gluc in plasma and urine based on liquid chromatography-tandem mass spectrometry. The liquid chromatography-electrospray ionization-tandem mass spectrometry method for quantitation of BPA and BPA-gluc uses stable isotope-labeled internal standards. A linear ion trap mass spectrometer permits identification and quantitation of BPA-gluc and BPA without sample workup. Development of separation conditions reduced the BPA-background in solvent samples to below 2.5 pmol/ml for BPA. Limit of quantitation (LOQ) for BPA in control urine was 15 pmol/ml; LOQ for BPA-gluc was 65 pmol/ml. Application of the method to urine samples from human subjects (n = 6) after administration of 25 microg of BPA/person (estimated maximum human daily intake) permitted the determination of excretion kinetics for BPA-gluc; BPA was below the LOD in all except two of the samples. In urine or blood samples of human subjects (n = 19) without intentional exposure to BPA, BPA concentrations were always below the limit of detection ( approximately 2.5 pmol/ml) with or without prior glucuronidase treatment. The results show that care is required for analysis of BPA and its major metabolite BPA-gluc. The LOD obtained and the absence of detectable levels of BPA in samples from individuals suggests that general exposure of humans to BPA is much lower than the worst-case exposure scenario developed.

Determination of bisphenol A in river water and body fluid samples by stir bar sorptive extraction with in situ derivatization and thermal desorption-gas chromatography–mass spectrometry

A new method, based on stir bar sorptive extraction (SBSE) with in situ derivatization and thermal desorption (TD)-gas chromatography–mass spectrometry (GC–MS) is described for the determination of trace amounts of bisphenol A (BPA) in river water, urine, plasma, and saliva samples. The derivatization conditions with acetic acid anhydride and the SBSE conditions such as sample volumes and extraction time are investigated. Then, the stir bar is subjected to TD followed by GC–MS. The detection limits of BPA in river water, urine, plasma, and saliva samples are 1–5, 20, 100, and 20 pg ml −1 (ppt), respectively. Calibration for BPA was shown to be linear with a correlation coefficient of >0.99. The average recoveries of BPA in all samples are higher than 95% (R.S.D. < 10%) with correction using an added surrogate standard, 13 C 12 -bisphenol A. This simple, accurate, sensitive, and selective analytical method may be applicable to the determination of trace amounts of BPA in liquid samples.