Multiple-stage mass spectrometry analysis of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether and their derivatives

Food and beverage can coatings: A review on chemical analysis, migration, and risk assessment

The internal surface of food and beverage cans is generally covered with polymeric coatings to preserve food and protect metal substrate from corrosion. Coating materials are complex formulations that contain different starting substances (e.g., monomers, prepolymers, additives, etc.) and in addition during the manufacture of the material several compounds can be formed (e.g., reaction products, degradation products, etc.). These substances have the potential to migrate into the food. Many of them have not been identified and only some have been toxicologically evaluated. This article aims to provide a comprehensive review on the analytical methods used for the identification of potential migrants in can coatings. The migration and exposure to chemicals migrating from can coatings are also reviewed and discussed so far, which is essential for risk assessment. Moreover, a brief section on the current status of the legislation on varnishes and coatings for food contact in Europe is also presented. Liquid chromatography coupled to diode array and fluorescence detectors and particularly to mass spectrometry and gas chromatography-tandem mass spectrometry seem to be the techniques of choice for the identification of potential migrants in can coatings. Some studies have reported migration levels of BPA (bisphenol A) and BADGE (bisphenol A diglycidyl ether) and derivatives exceeding the specific migration limits set in the European legislation. On the whole, low dietary exposure to migrants from can coatings has been reported. However, it is interesting to highlight that in these studies the combined exposure to multiple chemicals has not been considered.

Differentiation of bisphenol F diglycidyl ether isomers and their derivatives by HPLC-MS and GC-MS-comment on the published data

Positional isomers of bisphenol F diglycidyl ether (BFDGE) have been analyzed by high-pressure liquid chromatography-mass spectrometry and by gas chromatography-mass spectrometry (HPLC-MS, GC-MS). Positional isomers of BFDGE derivatives (BFDGEx2H₂O, BFDGExH₂OxHCl) have been analyzed by HPLC-MS. On the basis of the obtained fragmentation patterns, the elution order of the isomers has been unequivocally determined, in standard solutions and in the sample of liquid obtained after rinsing an empty mackerel fish can with acetonitrile. Under HPLC condition, para,para isomers are eluted first, then ortho,para isomers’ elution follows, and ortho,ortho isomers are eluted last. Under GC condition, the reverse elution order has been obtained. For the first time, two ortho,para isomers of BFDGExH₂OxHCl have been detected and their elution order has been determined. The obtained results are of key importance for determination of the isomer distribution of BFDGE and its derivatives in food samples.

Human phase I in vitro liver metabolism of two bisphenolic diglycidyl ethers BADGE and BFDGE

Root canal sealers are commonly used to endodontically treat teeth with periapical infections. Some root canal sealers based on epoxy resin contain bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE). The presence of these chemicals is of concern due to the close contact to the blood stream at the apex and the long setting times of up to 24 h. These chemicals, or any of their degradation products or metabolites, can then exert their toxic effects before being excreted. This study aimed to identify the phase I in vitro biotransformation products of BADGE and BFDGE using human liver microsomes. During incubation with microsomal fractions, the epoxides were rapidly hydrolysed in a NADPH independent manner resulting in the formation of BADGE.2H₂O and BFDGE.2H₂O. Further, oxidative reactions, such as hydroxylation and carboxylation, generated other BADGE metabolites, such as BADGE.2H₂O-OH and BADGE.H₂O.COOH, respectively. For BFDGE, further oxidation of BFDGE.2H₂O led to the newly reported carboxylic acid, BFDGE.H₂O.COOH. In total, three specific metabolites have been identified which can serve in future human biomonitoring studies of BADGE and BFDGE.

High-performance liquid chromatography (HPLC)-fluorescence method for determination of bisphenol A diglycidyl ether (BADGE) and its derivatives in canned foods

Bisphenol A diglycidyl ether (BADGE) is used as a raw material for the production of epoxy resins and PVC organosols, which are commonly applied as inner coatings for food cans. BADGE and its derivatives can migrate from coatings to foodstuffs during processing and storage thereby creating adverse health issues. In this work, a method based on high-performance liquid chromatography (HPLC)-fluorescence detection (FLD) method was developed for the rapid determination of BADGE and its five derivatives in canned foods. Modeling software DryLab® was applied for the optimization of separation conditions. An adequate separation was achieved in 5 min including equilibration time, using a core-shell particle column; such application has not been reported so far. Also, the results showed that LOD varied from 0.01 to 0.20 ng/g, while LOQ varied from 0.03 to 0.66 ng/g, and RSD was found to be <8.64%. The analytical recoveries ranged from 70.46 to 103.44%. Excellent validation data revealed that this method is suitable for the investigation of can coating-to-food migration of BADGE and its derivatives. The HPLC-FLD method is rapid, inexpensive and highly efficient, which could be applicable for safety inspection of food contact materials involving BADGE and its derivatives.

Ion-Trap Mass Spectrometric Analysis of Bisphenol A Interactions With Titanium Dioxide Nanoparticles and Milk Proteins

Quantitative analysis of endocrine-disrupting molecules such as bisphenol A (BPA) in freshwater to determine their widespread occurrence in environmental resources has been challenged by various adsorption and desorption processes. In this work, ion trap mass spectrometry (ITMS) analysis of BPA was aimed at studying its molecular interactions with titanium dioxide (TiO2) nanoparticles and milk whey proteins. Addition of sodium formate prevented TiO2 nanoparticles from sedimentation while enhancing the electrospray ionization (ESI) efficiency to produce an abundance of [BPA + Na]+ ions at m/z 251.0. More importantly, the ESI-ITMS instrument could operate properly during a direct infusion of nanoparticles up to 500 μg/mL without clogging the intake capillary. Milk protein adsorption of BPA could decrease the [BPA + Na]+ peak intensity significantly unless the proteins were partially removed by curdling to produce whey, which allowed BPA desorption during ESI for quantitative analysis by ITMS.

GC-MS Screening for the Identification of Potential Migrants Present in Polymeric Coatings of Food Cans

The coatings used in cans can release complex chemical mixtures into foodstuffs. Therefore, it is important to develop analytical methods for the identification of these potential migrant compounds in packaged food to guarantee the compliance with European food packaging legislation and ensure consumer safety. In the present work, the type of coating in a total of twelve cans collected in Santiago de Compostela (Spain) were evaluated using an ATR (attenuated total reflectance)-FTIR spectrometer. These samples were analysed after extraction with acetonitrile in order to identify potential migrants through a screening method by gas chromatography coupled to mass spectrometry (GC-MS). A total of forty-seven volatile and semi-volatile compounds were identified in these samples, including plasticizers, photoinitiators, antioxidants, lubricants, etc. Then, in a second step, a targeted analysis was carried out for the simultaneous determination of 13 compounds, including bisphenols (BPA, BPB, BPC, BPE, BPF, BPG) and BADGEs (BADGE, BADGE.H₂O, BADGE.2H₂O, BADGE.HCl, BADGE.2HCl, BADGE.H₂O.HCl, cyclo-di-BADGE) by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with atmospheric pressure chemical ionisation (APCI) source. Among all the bisphenols analysed, only the bisphenol A was detected in four samples; while cyclo-di-BADGE was the predominant compound detected in all the samples analysed.

A method to determine BPA, BPB, and BPF levels in fruit juices by liquid chromatography coupled to tandem mass spectrometry

The monitoring of the contamination levels of bisphenol A (BPA) and its congeners bisphenol B (BPB) and bisphenol F (BPF) in foodstuffs is a necessary process for assessment of consumers' risk. After development and validation of a method using Strata® C18-E cartridge cleanup with detection by liquid chromatography coupled to tandem mass spectrometry, forty-six samples of fruit juices, sold on Italian markets, have been analysed to assess the concentration of BPA, BPB and BPF. BPB and BPF were not detected in any samples, BPA was found in 33 % of the samples. The observed levels ranged from 0.50 ng mL^-1 to 2.85 ng mL^-1. Potential Daily Intakes (PDI) of BPA for Italian populations were calculated by the budget method model. PDIs ranged from 0.012 to 0.285 μg kg^-1 bw day^-1. None of the calculated values exceeded the current temporary TDI of 4 μg kg^-1 bw day^-1.

Concentrations of Bisphenols in Canned Foods and Their Risk Assessment in Korea

The purpose of this study was to survey concentrations of bisphenols in canned foods using liquid chromatography-tandem mass spectrometry, to estimate the dietary exposure to bisphenols, and to assess the related risk for the Korean population from the intake of canned foods. The linearity of bisphenols in the range of 2.5 to 725 μg/L was satisfactory with correlation coefficients ( r²) of 0.999. The limit of detection was 0.14 to 5.85 μg/L, and the limit of quantitation was 0.44 to 17.73 μg/L. Sample recoveries were 70.56 to 113.6%, with relative standard deviations below 10% for spiking levels of 50 and 250 μg/kg (15 and 75 μg/kg for BPS). The bisphenol concentrations in 104 canned foods ranged from undetectable to 1,525 μg/kg. The estimated mean daily intake of bisphenols was 0.54 to 78.69 ng/kg of body weight per day, and the 95th percentile daily intake was 1.92 to 134 ng/kg of body weight per day. Therefore, the intake of bisphenols from canned foods for the population in Korea is unlikely to cause human health problems. The analytical methods used are suitable for regular monitoring and assessment of human exposure to bisphenols from foods.

Monitoring of bisphenol A and bisphenol S in thermal paper receipts from the Italian market and estimated transdermal human intake: A pilot study

Bisphenol A (BPA), a synthetic xenoestrogen widely used in various industrial fields, can be present, in its un-reacted form, as an additive in thermal paper. BPA is virtually ubiquitous in industrialized societies and humans are exposed to this chemical via dietary and non-dietary sources. Since in 2015 European Food Safety Authority (EFSA) indicated that thermal paper is the second source of BPA exposure after the food chain, some suppliers replaced BPA with its analogue Bisphenol S (BPS), speculatively supposed to be safer. In this work BPA and BPS concentration levels were determined in thermal paper receipts collected in Italy from 50 different sources by liquid chromatography coupled to tandem fluorescence and ultraviolet detection. BPA was found in 44 samples at mean concentration of 107.47μg/100mg of paper (from below Limits of Quantification (LOQ) to 1533.733μg/100mg of paper). BPS was found in 31 samples at mean concentration of 41.97μg/100mg of paper (from below the LOQ to 357.989μg/100mg of paper). 26 samples were positive to both BPA and BPS. The estimate daily intake (EDI) values of BPA and BPS occurring through dermal absorption were calculated for 70kg body weight individuals. For general population, they were 0.0625μg/day for BPA and 0.0244μg/day for BPS, based on the mean content of bisphenols found. For occupationally exposed individuals, they were 66.8μg/day for BPA and 15.6μg/day for BPS, based on the worst scenario. Such levels would produce a dermal intake below the Tolerable Day Intake established by EFSA (4μg/kg·bw/day); nevertheless, the occurrence of co-exposure to dietary and non-dietary sources should be considered in the health risk assessment, mainly for people frequently exposed to thermal paper contact for occupational reason.

Evaluation of Endocrine Disrupting Compounds Migration in Household Food Containers under Domestic Use Conditions

Plasticizers and plastic monomers are commonly used in packaging. Most of them act as endocrine disrupters and are susceptible to migrate from the packaging to the food. We evaluated the migration of endocrine disrupting compounds from three different household food containers to four food simulants under different domestic treatments and for different periods of time, with the aim of reproducing real domestic conditions. The results showed that the migration to the simulants increased with the storage time, up to more than 50 times in certain cases. The heating power seemed to increase the migration processes (up to more than 30 times), and reusing containers produced an increase or decrease of the concentrations depending on the container type and the simulant. The concentrations found were lower than other concentrations reported (always less than 4000 pg/mL, down to less than 20 pg/mL), which might be a consequence of the domestic conditions used.

A high-throughput screening method of bisphenols, bisphenols digycidyl ethers and their derivatives in dairy products by ultra-high performance liquid chromatography-tandem mass spectrometry

A simple and universal analytical method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for high throughput screening of 21 bisphenols, bisphenols digycidyl ethers and their derivatives in dairy products was developed. Response Surface Methodology (RSM) was used to optimize sample preparation conditions based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) method. The analytes were extracted by using 15 mL acetonitrile with 1% acetic acid, and the extracts were further purified by using 190 mg of C18 and 390 mg of PSA. The extracts were analyzed by UHPLC-MS/MS with electrospray ionization (ESI) source. Linearity was assessed by using matrix-matched standard calibration and good correlation coefficients (r² > 0.99) were obtained. The limits of quantitation (LOQs) for the analytes ranged from 0.02 to 5 μg kg^-1. The extraction recoveries were in a range of 88.2%-108.2%. Good method reproducibility in terms of intra- and inter-day precision was observed, yielding relative standard deviations (RSDs) less than 8.9% and 9.9%, respectively. The validation method results revealed that the proposed method was sensitive and reliable. Finally, this method was successfully applied to dairy product analysis.

Optimum pH for the determination of bisphenols and their corresponding diglycidyl ethers by gas chromatography-mass spectrometry. Migration kinetics of bisphenol A from polycarbonate glasses

This paper presents, on the one hand, the study of the influence of the pH of the medium on the determination of bisphenol F (BPF), bisphenol A (BPA) and their corresponding diglycidyl ethers (BFDGE and BADGE, respectively) by GC-MS after a solid-phase extraction step, using BPA-d16 as internal standard and Parallel Factor Analysis (PARAFAC) decomposition as a multi-way tool for the unequivocal identification and quantification of the four analytes. As the structure of both BFDGE and BADGE has two 2,3-epoxypropoxy groups that can undergo an acid- or base-catalyzed ring-opening via nucleophilic substitution reactions, several samples spiked with the four analytes were set to different pH values between 2 and 12. The best results were obtained in the pH region 8-10, being 9 the most suitable value. Coelution of interferents was overcome using the PARAFAC decomposition; otherwise, the presence of some analytes could not have been ensured according to the regulations currently in force. Secondly, the release of BPA from polycarbonate glasses into food simulant D1 (ethanol 50% (v/v)) over time was studied through seven migration tests and the differences found in this migration process with the incubation temperature (50 and 70°C) were evaluated. A nonlinear regression was used to fit the experimental data following an exponential relation between the concentration of BPA transferred from every glass and the respective migration test. None of the quantities of BPA released exceeded the specific migration limit of 0.6mgkg(-1) laid down for this compound in the Commission Regulation (EU) No 10/2011, so the compliance of the glasses evaluated was ensured. The average recovery percentages of the four analytes at a fortification level of 800ngL(-1) ranged from 50.14 to 92.75%. The detection capability (CCβ) of the method for BPA was 2.60μgL(-1) for n=2 replicates, with probabilities of false positive and false negative fixed at 0.05.

A LC-MS/MS method for the determination of BADGE-related and BFDGE-related compounds in canned fish food samples based on the formation of [M+NH(4)](+) aducts

A new and simple liquid chromatography tandem mass-spectrometry method for the determination of different bisphenol A (BPA) derivatives such as bisphenol A diglycidyl ether (BADGE), bisphenol F diglycidyl ether (BFDGE) and their reaction products with water and hydrochloric acid in different fish food products was developed. The extraction procedure and the chromatographic conditions were optimised for complex food matrices such as fish products. Food samples were homogenised and extracted with a 1:1 solution of acetonitrile-hexane, the solvent was eliminated in a N(2) stream and the extract was reconstituted with 0.5mL of a 0.01M solution of ammonium formate. The sample solution obtained was directly measured by LC-MS/MS without any further purification under the developed conditions. The use of a mobile phase composed by ammonium formate-methanol in a binary gradient mode produced [M+NH(4)](+) aducts for the different BADGEs and BFDGEs. These aduct's fragmentations were employed for the LC-MS/MS quantification of BPA derivatives in canned fish samples. The results of the validation were appropriate: the method was linear for BADGE and its hydrolysed derivatives up to 1000μgkg(-1), for the remaining compounds linearity achieved up to 100μgkg(-1). Quantification limits were in the range 2-10μgkg(-1). RSD (intra and inter-day) was 6-12% and the recovery was comprised between 89% and 109%. Under the optimised conditions, the chromatographic separation was performed in 8min per sample. The method was applied to the determination of BADGE, BFDGE and their reaction products in different samples of canned fish from Spanish origin. Migration results obtained were in compliance with the EU regulations.

Fast liquid chromatography-tandem mass spectrometry for the analysis of bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether and their derivatives in canned food and beverages

In this work a fast liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method using a C18 Fused Core™ column, was developed for the simultaneous analysis of bisphenol A diglycidyl ether (BADGE), bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE·H(2)O), bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE·2H(2)O), bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether (BADGE·HCl), bisphenol A bis(3-chloro-2-hydroxypropyl) ether (BADGE·2HCl) and bisphenol A (3-chloro-2-hydroxypropyl)(2,3-dihydroxypropyl ether) (BADGE·HCl·H(2)O) and bisphenol F diglycidyl ether (BFDGE), bisphenol F bis(2,3-dihydroxypropyl) ether (BFDGE·2H(2)O), bisphenol F bis(3-chloro-2-hydroxypropyl) ether (BFDGE·2HCl). The LC method was coupled with a triple quadrupole mass spectrometer, using an ESI source in positive mode and using the [M+NH(4)](+) adduct as precursor ion for tandem mass spectrometry experiments. The method developed was applied to the determination of these compounds in canned soft drinks and canned food. OASIS HLB solid phase extraction (SPE) cartridges were used for the analysis of soft drinks, while solid canned food was extracted with ethyl acetate. Method limits of quantitation ranged from 0.13 μgL(-1) to 1.6 μgL(-1) in soft drinks and 1.0 μgkg(-1) to 4.0 μgkg(-1) in food samples. BADGE·2H(2)O was detected in all the analyzed samples, while other BADGEs such as BADGE·H(2)O, BADGE·HCl·H(2)O, BADGE·HCl and BADGE·2HCl were also detected in canned foods.