Challenges in relating concentrations of aromas and tastes with flavor features of foods.

Flavor sensations in food are highly influenced by the aroma and taste compounds. Reviewing the extensive literature of recent years in this field has shown that the reconstitution of flavor based on aroma and taste compounds poses numerous problems. These are of different nature and include among others (a) chemical transformations among these compounds, (b) changes in the concentrations of the compounds responsible for the perceived flavor, (c) interactions among the chemical compounds that enhance or reduce a specific flavor sensation, and finally, (d) the complexity of the different food matrices and its influence in the flavor perception. Another difficulty that flavor scientists must face is how to properly model and visualize the complex relationships existing between the chemical composition of foods and the flavor perception. These problems have repercussions on the reconstitution of the flavor signature of food based on the natural concentrations of its key aroma and taste compounds. Therefore, the main aim of this review is to deal with all these issues to propose potential solutions for a robust transformation in a science-based quality approach.

Optimization of a Differential Ion Mobility Spectrometry-Tandem Mass Spectrometry Method for High-Throughput Analysis of Nicotine and Related Compounds: Application to Electronic Cigarette Refill Liquids.

Fast market penetration of electronic cigarettes is leading to an exponentially growing number of electronic refill liquids with different nicotine contents and an endless list of flavors. Therefore, rapid and simple methods allowing a fast screening of these products are necessary to detect harmful substances which can negatively impact the health of consumers. In this regard, the present work explores the capabilities of differential ion mobility spectrometry coupled to tandem mass spectrometry for high-throughput analysis of nicotine and 11 related compounds in commercial refill liquids for electronic cigarettes. The influence of main factors affecting the ion mobility separation, such as modifier types and concentration, separation voltage, and temperature, was systematically investigated. Despite small molecular weight differences among the studied compounds, a good separation was achieved in the ion mobility cell under the optimized conditions, which involved the use of ethanol as a polar gas-phase chemical modifier. Indeed, differential ion mobility was able to resolve (resolution >4) nicotine from its structural isomer anabasine without the use of any chromatographic separation. The quantitative performance of the proposed method was then evaluated, showing satisfactory precision (RSD ≤ 16%) and recoveries ranging from 85 to 100% for nicotine, and from 84 to 126% for the rest of the target analytes. Several commercial electronic cigarette refill liquids were analyzed to demonstrate the applicability of the method. In some cases, significant differences were found between labeled and measured levels of nicotine. Anatabine, cotinine, myosmine, and nornicotine were also found in some of the analyzed samples.

Ion-Mobility-Derived Collision Cross Section as an Additional Identification Point for Multiresidue Screening of Pesticides in Fish Feed.

Ion mobility spectrometry allows for the measurement of the collision cross section (CCS), which provides information about the shape of an ionic molecule in the gas phase. Although the hyphenation of traveling-wave ion mobility spectrometry (TWIMS) with high-resolution quadrupole time-of-flight mass spectrometry (QTOFMS) has been mainly used for structural elucidation purposes, its potential for fast screening of small molecules in complex samples has not yet been thoroughly evaluated. The current work explores the capabilities of ultrahigh-performance liquid chromatography (UHPLC) coupled to a new design TWIMS-QTOFMS for the screening and identification of a large set of pesticides in complex salmon feed matrices. A database containing TWIMS-derived CCS values for more than 200 pesticides is hereby presented. CCS measurements showed high intra- and interday repeatability (RSD < 1%), and they were not affected by the complexity of the investigated matrices (ΔCCS ≤ 1.8%). The use of TWIMS in combination with QTOFMS was demonstrated to provide an extra-dimension, which resulted in increased peak capacity and selectivity in real samples. Thus, many false-positive detections could be straightforwardly discarded just by applying a maximum ΔCCS tolerance of ±2%. CCS was proposed as a valuable additional identification point in the pesticides screening workflow. Several commercial fish feed samples were finally analyzed to demonstrate the applicability of the proposed approach. Ethoxyquin and pirimiphos-methyl were identified in most of the analyzed samples, whereas tebuconazole and piperonil butoxide were identified for the first time in fish feed samples.

A review on the fermentation of foods and the residues of pesticides-biotransformation of pesticides and effects on fermentation and food quality.

Residues of pesticides in food are influenced by processing such as fermentation. Reviewing the extensive literature showed that in most cases, this step leads to large reductions in original residue levels in the fermented food, with the formation of new pesticide by-products. The behavior of residues in fermentation can be rationalized in terms of the physical-chemical properties of the pesticide and the nature of the process. In addition, the presence of pesticides decrease the growth rate of fermentative microbiota (yeasts and bacterias), which provokes stuck and sluggish fermentations. These changes have in consequence repercussions on several aspects of food sensory quality (physical-chemical properties, polyphenolic content, and aromatic profile) of fermented food. The main aim of this review is to deal with all these topics to propose challenging needs in science-based quality management of pesticides residues in food.

Derivatization of bisphenol A and its analogues with pyridine-3-sulfonyl chloride: multivariate optimization and fragmentation patterns by liquid chromatography/Orbitrap mass spectrometry.

RATIONALE: Due to the growing restrictions on the use of bisphenol A (BPA), several other bisphenols are gaining importance as substitutes for BPA in a variety of applications. There is, therefore, a real need for selective and sensitive methods based on mass spectrometry which will allow the human exposure to these new bisphenols to be assessed. METHODS: Derivatization of BPA and its substitutes with pyridine-3-sulfonyl chloride is used to enhance the detection capability of bisphenols by electrospray ionization mass spectrometry. A multivariate experimental design, Box-Behnken response surface, was used to evaluate the influence of the main variables potentially affecting the derivatization yield. Fragmentation patterns for all the derivatized bisphenols were acquired by high-resolution/accurate-mass Orbitrap mass spectrometry. RESULTS: Temperature and pH were identified as the most important factors affecting the derivatization yield of bisphenols. Fragmentation of the protonated molecules produced abundant analyte-specific product ions. Most of the derivatized bisphenols showed significant improvements in their signal-to-noise ratios compared with the underivatized forms. The stability of these derivatives was demonstrated through several freeze/thaw cycles, short-term room temperature and long-term cold storage. CONCLUSIONS: Derivatization of BPA and its structural analogues with pyridine-3-sulfonyl chloride is proposed as a specific, sensitive, high-throughput approach to their analysis by liquid chromatography coupled to electrospray ionization mass spectrometry.

Toxicity evaluation of new agricultural fungicides in primary cultured cortical neurons.

Fungicides are crucial for food protection as well as for the production of crops of suitable quality and quantity to provide a viable economic return. Like other pesticides, fungicides are widely sprayed on agricultural land, especially in wine-growing areas, from where they can move-off after application. Furthermore, residues of these agrochemicals can remain on crops after harvest and even after some food processing operations, being a major exposure pathway. Although a relatively low toxicity has been claimed for this kind of compounds, information about their neurotoxicity is still scarce. In the present study, nine fungicides recently approved for agricultural uses in the EU - ametoctradin, boscalid, cyazofamid, dimethomorph, fenhexamid, kresoxim-methyl, mepanipyrim, metrafenone and pyraclostrobin - have been evaluated for their toxicity in primary cultured mouse cortical neurons. Exposure to 0.1-100µM for 7 days in vitro resulted in a dose-dependent toxicity in the MTT cell viability assay. Strobilurin fungicides kresoxim-methyl (KR) and pyraclostrobin (PY) were the most neurotoxic compounds (lethal concentration 50 were in the low micromolar and nanomolar levels, respectively) causing a rapid raise in intracellular calcium [Ca(2+)]i and strong depolarization of mitochondrial membrane potential. KR- and PY-induced cell death was reversed by the calcium channels blockers MK-801 and verapamil, suggesting that calcium entry through NMDA receptors and voltage-operated calcium channels are involved in KR- and PY-induced neurotoxicity. These results highlight the need for further evaluation of their neurotoxic effects in vivo.

Carotenoid profile of tomato sauces: effect of cooking time and content of extra virgin olive oil.

The consumption of carotenoid-rich vegetables such as tomatoes and tomato sauces is associated with reduced risk of several chronic diseases. The predominant carotenoids in tomato products are in the (all-E) configuration, but (Z) isomers can be formed during thermal processing. The effect of cooking time (15, 30, 45 and 60 min) and the addition of extra virgin olive oil (5% and 10%) on the carotenoid extractability of tomato sauces was monitored using liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) and LC-ultraviolet detection (LC-UV). The thermal treatment and the addition of extra virgin olive oil increased the levels of antioxidant activity, total carotenoids, Z-lycopene isomers, α-carotene and ß-carotene. These results are of particular nutritional benefit since higher lycopene intake has been associated with a reduced risk of lethal prostate and a reduction of prostate-specific antigen (PSA) levels. Moreover, ß-carotene has been reported to suppress the up-regulation of heme oxygenase-1 gene expression in a dose dependent manner and to suppress UVA-induced HO-1 gene expression in cultured FEK4.

Urinary tartaric acid as a potential biomarker for the dietary assessment of moderate wine consumption: a randomised controlled trial.

The availability of biomarkers that allow the estimation of the intake of specific foods and dietary components, as an alternative or addition to self-reported dietary questionnaires, could greatly enhance the effectiveness of nutritional research. The aim of the present study was to assess tartaric acid, one of the major components of red and white wines, as a potential biomarker of wine consumption. A total of twenty-one healthy men participated in a randomised cross-over feeding trial. They consumed a single dose of 100, 200 or 300 ml wine at dinner. Before each intervention, the participants followed a 7 d washout period during which they avoided consuming wine or grape-based products. Morning urine was collected and analysed by liquid chromatography coupled to electrospray ionisation tandem MS. A strong significant correlation was found between wine intake and urinary tartaric acid (r(s) = 0·9220; P <0·001). Using a cut-off value of 8·84 µg/mg creatinine, tartaric acid allowed wine consumers to be differentiated from non-wine consumers. The results suggest that urinary tartaric acid may be a sensitive and specific dietary biomarker of wine consumption.

Analysis of industrial contaminants in indoor air: part 1. Volatile organic compounds, carbonyl compounds, polycyclic aromatic hydrocarbons and polychlorinated biphenyls.

This article reviews recent literature on the analysis of industrial contaminants in indoor air in the framework of the REACH project, which is mainly intended to improve protection of human health and the environment from the risks of more than 34 millions of chemical substances. Industrial pollutants that can be found in indoor air may be of very different types and origin, belonging to the volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) categories. Several compounds have been classified into the priority organic pollutants (POPs) class such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/PCDFs) and related polychlorinated compounds, and polycyclic aromatic hydrocarbons (PAHs). Many of these compounds are partially associated to the air gas phase, but also to the suspended particulate matter. Furthermore, settled dust can act as a concentrator for the less volatile pollutants and has become a matrix of great concern for indoors contamination. Main literature considered in this review are papers from the last 10 years reporting analytical developments and applications regarding VOCs, aldehydes and other carbonyls, PCBs, PCDDs, PCDFs, and PAHs in the indoor environment. Sample collection and pretreatment, analyte extraction, clean-up procedures, determination techniques, performance results, as well as compound concentrations in indoor samples, are summarized and discussed. Emergent contaminants and pesticides related to the industrial development that can be found in indoor air are reviewed in a second part in this volume.

Analysis of industrial contaminants in indoor air. Part 2. Emergent contaminants and pesticides.

This article reviews recent literature on the analysis of several contaminants related to the industrial development in indoor air in the framework of the REACH project. In this second part, the attention is focused on emergent contaminants and biocides. Among these chemicals, phthalates, polybrominated and phosphate flame retardants, fragrances, pesticides, as well as other emerging pollutants, are increasing their environmental and health concern and are extensively found in indoor air. Some of them are suspected to behave as priority organic pollutants (POPs) and/or endocrine disrupting compounds (EDC), and can be found both in air and associated to the suspended particulate matter (PM) and settled dust. Main literature considered for this review is from the last ten years, reporting analytical developments and applications regarding the considered contaminants in the indoor environment. Sample collection and pretreatment, analyte extraction or desorption, clean-up procedures, determination techniques, and performance results are summarized and discussed.

Determination of dimethyl fumarate and other potential allergens in desiccant and antimould sachets.

A method for the determination of dimethyl fumarate (DMF), benzothiazole (BT) and tert-butylphenol (TBP) in desiccant and antimould agents employed for protecting consumer products from humidity and mould has been developed. The method is based on ultrasound-assisted extraction (UAE) followed by GC-MS analysis. Parameters that could affect the extraction of the compounds have been optimised using a multivariate approach. In the final conditions, the extraction is performed using only 0.5 or 1 mL ethyl acetate and applying ultrasound energy for 5 min. Simultaneous extractions could also be carried out in 5 min without losing efficiency. The method was validated showing good linearity (R2 >0.995). Both intra- and inter-day precisions were studied at several concentration levels, being satisfactory in all cases (RSD <10%). Recovery was evaluated in four real desiccant samples at different compound concentrations, ranging between 87% and 109%. Limits of detection and quantification were in the low nanogramme per gramme level, thus allowing the determination of DMF at concentrations well below the limit established by the recent EU Directive (0.1 microg/g). The proposed procedure was applied to the determination of the target compounds in several desiccant and antimould samples. Although most of them were simply labelled as "silica gel", more than 70% of the tested samples contained high amounts of DMF, many of them at the high microgram per gramme level. Many samples also showed the presence of the other two potential allergens. These results demonstrate that the content of the "desiccant" sachets and tablets in consumer products does not usually belong with the label of the desiccant, and hence, the high risk of exposition to the powerful allergen DMF and other potentially harmful chemicals through consumer goods should be a matter of concern.

Identification of ethoxyquin and its transformation products in salmon after controlled dietary exposure via fish feed.

Ethoxyquin (EQ) is an additive present in fish feed and its fate in fish should be carefully characterized due to food safety concerns regarding this compound. Therefore, the objective of this work was to identify the transformation products (TPs) of EQ in Atlantic salmon. Salmon in independent tanks were given feed containing ethoxyquin concentrations of 0.5 mg/kg, 119 mg/kg or 1173 mg/kg for 90 days. After the feeding trial, salmon fillets were extracted in acetonitrile and analyzed by liquid chromatography with traveling-wave ion mobility spectrometry coupled to high resolution mass spectrometry (UHPLC-TWIMS-QTOFMS). EQ was transferred from the feed to salmon fillets and 23 TPs were characterized, resulting from dimerization, oxygenation, cleavage, cleavage combined with oxygenation, cleavage combined with conjugation, and other uncategorized alterations. Moreover, EQ and some TPs were also detected in commercial salmon randomly sampled from different Norwegian fish farms. This study confirmed that the dimer 1,8'-EQDM was the main TP of EQ and, together with previous research, brought the overall number of characterized TPs to a total of 47.

Ultrasound-assisted emulsification-microextraction of emergent contaminants and pesticides in environmental waters.

The analytical use of ultrasound-generated emulsions has recently found a growing interest to improve efficiency in liquid-liquid extraction since they increase the speed of the mass transfer between the two immiscible phases implied. Thus, dispersed droplets can act as efficient liquid-liquid microextractors in the continuous phase, and later they can be readily separated by centrifugation. A novel method based on ultrasound-assisted emulsification-microextraction (USAEME) and gas chromatography coupled to mass spectrometry (GC/MS) has been developed for the analysis of synthetic musk fragrances, phthalate esters and lindane in water samples. Extraction conditions were optimized using a multivariate approach. Compounds were extracted during 10 min in an acoustically emulsified media formed by 100 microL chloroform and 10 mL sample (enrichment factor=100). The method performance was studied in terms of accuracy (recovery=78-114%), linearity (R2> or =0.9990) and repeatability (RSD< or =14%). Limits of detection (LODs) were at the pg mL(-1) level for most of compounds, and at the sub-ng mL(-1) level for the most ubiquitous phthalate esters. USAEME is proposed as an efficient, fast, simple and non-expensive alternative to other extraction techniques such as SPE, SPME and LPME for the analysis of environmental waters including bottled, tap, river, municipal swimming pool, sewage and seaport water samples. Since no matrix effect has been found for any of the water types analyzed, quantification could be carried out by using conventional external calibration, thus allowing a higher throughput of the analysis in comparison with other microextraction techniques based on equilibrium such as solid-phase microextraction.

Development of a high-throughput method for the determination of organochlorinated compounds, nitromusks and pyrethroid insecticides in indoor dust.

Investigation of chemical exposure inside the homes and offices where people spend the majority of their lives has only recently begun. These chemicals are degraded much more slowly than outdoor because they are more protected from sunlight, severe environmental conditions and microbial activity. Hence, indoor dust has been recognized as an important exposure pathway for organic contaminants. Pyrethroids are synthetic insecticides widely used in domestic environment for numerous applications and also in agriculture. Chlorobenzenes are a family of compounds used as intermediates in the production of a wide range of household consumer products. Nitromusks are a kind of synthetic musks used in the production of cleaning agents, detergents, and personal care products. A high-throughput method for the determination of these compounds in indoor dust samples has been developed. Microwave-assisted solvent extraction was used as the extraction technique whereas quantification of compounds was carried out by gas chromatography with micro-electron-capture detection. Several cleanup procedures were tested and finally a non-classical "on batch" procedure was selected, which allows increasing the throughput of the analysis while decreasing sample manipulation. Extraction conditions were optimized using a multifactorial experimental design approach. Quantitative recovery (84-103%) was achieved for all compounds and method precision was satisfactory. Limits of detection ranged from 0.22 ng g(-1) for lindane to 40 ng g(-1) for 1,4-dichlorobenzene. Standard reference material SRM 2585 was analyzed and the obtained values were in good agreement with the reported reference values for organochlorinated compounds and nitromusks. Pyrethroids and polychlorobenzenes have been analyzed for the first time in this reference material and some of them have been found. In addition, real samples collected in houses of north-western Spain have been analyzed by the proposed method and 17 of the 22 target compounds have been detected in the samples.

Comprehensive characterization of ethoxyquin transformation products in fish feed by traveling-wave ion mobility spectrometry coupled to quadrupole time-of-flight mass spectrometry.

Feed additives are typically used in intensive farming production over long periods, and hence, they can accumulate in farmed animal tissues. Concerns regarding the use of ethoxyquin as an antioxidant feed additive, have recently arisen due to its potential conversion into a series of transformation products (TPs). The aim of this work was to characterize the TPs of ethoxyquin in fish feed by a novel approach based on the use of traveling-wave ion mobility spectrometry (TWIMS) coupled to high-resolution quadrupole time-of-flight mass spectrometry (QTOFMS). First, ethoxyquin was oxidized under controlled conditions and the generated TPs were added to a comprehensive database. Atlantic salmon feeds were then screened for ethoxyquin TPs using both targeted and untargeted approaches. Twenty-seven TPs were tentatively identified during the oxidation experiments, fifteen of them also being present in the feed samples. In addition, ten other potential TPs were detected in fish feed following the untargeted approach. Thirty-one of these TPs have been reported for the first time in this work through the oxidation experiments and the feed samples. Therefore, this study provides valuable information on the oxidative fate of ethoxyquin in feed, which can be used for future evaluations of potential risk related to this additive.

Dietary exposure and neurotoxicity of the environmental free and bound toxin ß-N-methylamino-l-alanine.

The growing evidence supporting a link between exposure to the naturally occurring toxin ß-N-methylamino-l-alanine (BMAA) and progressive neurodegenerative diseases, has recently arisen the interest of the scientific community. Latest investigations suggest that dietary exposure to this algal toxin may have been largely underestimated. This paper reviews the state of the art regarding BMAA, with special attention paid to its neurotoxicity, its concentration levels in food, and human exposure. As for other environmental toxins, dietary intake is most likely the main route of exposure to BMAA for the general population. However, data concerning BMAA levels in foodstuffs are still scarce. It is concluded that further investigations on dietary intake and potential human health effects are clearly necessary to assess the risks to public health associated with BMAA exposure. Some critical remarks and recommendations on future research in this area are provided, which may help to identify approaches to reduce dietary BMAA exposure.

Determination of polybrominated diphenyl ethers in domestic dust by microwave-assisted solvent extraction and gas chromatography-tandem mass spectrometry.

In this paper, a rapid and simple method for the analysis of polybrominated diphenyl ethers (PBDEs) in house dust samples based on microwave-assisted solvent extraction (MASE) and gas chromatography-tandem mass spectrometry (GC-MS/MS) is presented. Extraction conditions were optimized using a multifactorial experimental design approach. The use of an aqueous NaOH phase in combination with a non-polar organic phase (hexane) to extract the target analytes from dust allowed an efficient extraction and reduced chromatographic background. The final hexane extracts could be analyzed after a simple one-step cleanup procedure using Florisil. The validation of the method was performed in terms of accuracy, linearity, and repeatability. The limits of detection (LODs) ranged from 0.29 to 0.55 ng/g for all compounds. The target PBDEs were found in several real dust samples collected in urban and rural houses of Northwestern Spain.

Gonyaulax taylorii, a new yessotoxins-producer dinoflagellate species from Chilean waters.

In summer 2009, during a survey in Bahía Mejillones, a dense bloom of a dinoflagellate from the genus Gonyaulax was detected, as well as the presence of yessotoxin. Phytoplankton samples were analyzed in detail by light and scanning electron microscopy (SEM), revealing the presence of Gonyaulax taylorii. Morphological examination showed that the cells in the bloom fit in Gonyaulax jollifei Murray et Whitting sensu Dodge, subsequently classified as Gonyaulax taylorii by Carbonell-Moore. In this context, some inconsistencies have been found in regard to the holotype; the plate 1"' appears as two plates, 1‴ and 2‴, showing a suture that does not exist in Dodge's figure of G. jollifei, from where the holotype was drawn, nor within the samples collected. Therefore, this plate has been originally described erroneously as two plates named 1"' and 2"' instead of only one named 1‴. After this correction, this species has five instead of six postcingular plates. For this reason, the description of this species must be emended. Phytoplankton net samples were found to contain yessotoxin and homoyessotoxin, with concentrations below 1pgcell-1. The present study identifies, therefore, the dinoflagellate G. taylorii as a new source of yessotoxins.

Reactivity of vinca alkaloids during water chlorination processes: Identification of their disinfection by-products by high-resolution quadrupole-Orbitrap mass spectrometry.

Concerns about the presence of anticancer drugs in the environment are rapidly increasing mainly due to their growing use in the developed countries and their known cytotoxic effects. Vinca alkaloids are widely used in cancer therapy; however, very scarce information is available on their occurrence, environmental fate and toxicological effects on aquatic organisms. Even less attention has been paid to their potential transformation products, which can exert higher toxicity than the parent compounds. Thus, in the present work, the reactivity of vincristine, vinblastine, vinorelbine and its metabolite 4-O-deacetyl vinorelbine during water chlorination processes has been investigated for the first time. Under the studied chlorination conditions, vincristine was fairly stable whereas vinblastine, vinorelbine and 4-O-deacetyl vinorelbine were quickly degraded. A total of sixty-five disinfection by-products were tentatively identified by ultra-high performance liquid chromatography coupled to high-resolution hybrid quadrupole-Orbitrap tandem mass spectrometry. Among them, twenty by-products corresponded to mono-chlorinated compounds, eight to di-chlorinated compounds and two to tri-chlorinated compounds, which may be of major environmental concern. Other disinfection by-products involved hydroxylation and oxidation reactions. Although the structures of these by-products could not be positively confirmed due to lack of commercial standards, their chemical formulas and product ions can be added to databases, which will allow their screening in future monitoring studies.

Determination of bisphenols in beverages by mixed-mode solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry.

Facing growing restrictions on the use of bisphenol A in food contact materials, several bisphenol analogs are arising as major alternatives to replace this chemical in most of its applications. This work reports a simple and robust method based on mixed-mode solid-phase extraction and stable-isotope dilution liquid chromatography-tandem mass spectrometry for the analysis of bisphenol A and its main analogs - bisphenol S, 4,4'-sulfonylbis(2-methylphenol), bisphenol F, bisphenol E, bisphenol B, bisphenol Z, bisphenol AF, bisphenol AP, tetrabromobisphenol A and bisphenol P - in alcoholic and non-alcoholic beverages. Mixed-mode solid-phase extraction, combining cationic exchange and reversed-phase mechanisms, was optimized to provide a selective extraction and purification of the target analytes. Derivatization of bisphenols with pyridine-3-sulfonyl chloride allowed increasing their ionization efficiency by electrospray ionization. Validation of the proposed method was performed in terms of selectivity, matrix effects, linearity, precision, measurement uncertainty, trueness and limits of detection. Satisfactory repeatability and intermediate precision were obtained; the related relative standard deviations were ≤9% and ≤12%, respectively. The relative expanded uncertainty (k=2) was below 20% for all bisphenol analogs and the trueness of the method was demonstrated by recovery experiments. Limits of detection (LOD) ranged from 1.6ngL(-1) to 27.9ngL(-1) for all compounds. Finally, several canned and non-canned beverages were analyzed to demonstrate the applicability of the method. Only bisphenol A and three bisphenol F isomers were detected in any of the samples. Bisphenol A concentration ranged from