Determination of pesticide residues in soybeans using QuEChERS followed by deep eutectic solvent-based DLLME preconcentration prior to gas chromatography-mass spectrometry analysis.

A reliable and greener alternative to the usual extraction methods is reported for the determination of pesticide residues in soybeans. This novel approach combines the classical QuEChERS extraction method with a DLLME (dispersive liquid-liquid microextraction) step, utilizing a deep eutectic solvent (DES) - camphor: hexanoic acid (1:1 molar ratio) - as the microextraction solvent. This DES has never been employed in pesticide analysis by gas chromatography-mass spectrometry of complex matrices like soybeans. A Plackett-Burman screening design was employed to optimize sample preparation variables of QuEChERS (amount of sodium chloride and magnesium sulfate, and amount of PSA and C18 sorbents) and DLLME (pH of medium, amount of sodium chloride, and volume of microextraction solvent). This design allowed for a systematic evaluation of the impact of each parameter on the method's performance. The optimized method was evaluated using a certified reference material and commercial samples of soybeans. The method exhibited high accuracy and precision for most of the analytes under study, demonstrating its applicability for pesticide residue analysis in soybeans. To assess the greenness and practicality of the developed method, the Analytical Greenness (AGREE) and Blue Applicability Grade Index (BAGI) metric systems were employed, respectively. Overall, the proposed QuEChERS-DLLME method using a DES solvent is a reliable and greener alternative to conventional extraction methods for the determination of pesticide residues in soybeans. Its high performance, coupled with its environmental friendliness, makes it a promising tool for food safety analysis.

Bisphenol A and its structural analogues in infant formulas available in the Brazilian market: Optimisation of a UPLC-MS/MS method, occurrence, and dietary exposure assessment.

For the first time, structural analogues to bisphenol A were investigated in infant formulas marketed in Brazil. A fast and high throughput UPLC-MS/MS method was established for simultaneous analysis of bisphenol A, B, E, F, and S in complex infant formula matrices. The influence of mobile phase composition on electrospray ionization response in negative mode was studied to improve the detectability of the method. As also, the main sample preparation variables that could affect the extraction and cleanup were screened by the Plackett-Burman design. The method performance characteristics were adequate, including reliable limits of detection (5-10 µg kg-1) and quantification (10-20 µg kg-1) with suitable recoveries (84.2-108.9 %) and precision (≤18 %). Sixty-one infant formulas were analyzed, and 36 % of total samples contained at least one bisphenol analogue, whose levels ranged between 10.9 and 198.9 µg kg-1. Based on a deterministic approach, the estimated daily intakes for babies up to 6 months old, fed exclusively with infant formula, were below the temporary tolerable daily intake of 4 µg kg-1 body weight set for bisphenol A by the European Food Safety Authority.

Occurrence and risk assessment of endocrine-disrupting compounds in fish muscle: The case study of the Douro River estuary (North East Atlantic Ocean).

This work was focused on evaluating the occurrence of endocrine-disrupting compounds (EDCs) in fish muscles, such as bisphenol analogues, personal care products, including some UV-filters and musk fragrances, and selected pesticides. A total of 238 muscle samples of three fish species (Platichthys flesus, Mugil cephalus, and Dicentrarchus labrax) of an important estuary ending in the North East Atlantic Ocean (Douro River estuary, Portugal), in different seasons of the year, was analysed. M. cephalus was the species with a greater occurrence of contaminants, mainly in fishes collected during the spring. Bisphenol A was the main bisphenol analogue detected with an average content of 23.1 µg/kg wet weight (w.w.). Among chemicals used in personal care products, galaxolide, tonalide, and 2-ethylhexyl salicylate, were the most often found, being present in 15.9% (2.2-538.4 µg/kg w. w.), 4.6% (1.1-57.8 µg/kg w. w.) and 3.4% (3.9-56.1 µg/kg w. w.) of the samples, respectively. About 14% of the samples contained residues of at least one pesticide, being alachlor, aldrin, p,p'-DDT, permethrin, and prochloraz the main chemicals observed, varying from 0.1 µg/kg w. w. (p,p'-DDT) to 37.8 µg/kg w. w. (prochloraz). The daily intake estimates of the most frequent EDCs found in the fish muscles suggested that there are no health concerns, based on the recommended weekly consumption of fish for adults.

Multi-analyte gas chromatography-mass spectrometry method to monitor bisphenols, musk fragrances, ultraviolet filters, and pesticide residues in seafood.

A gas chromatography-mass spectrometry method for the analysis of thirty-six anthropogenic contaminants in the edible portion of four distinct seafood items is reported. Considering the heterogeneous composition of algae, mussels, and lean/fatty fish muscles, a generic sample preparation based on the QuEChERS procedure combined with dispersive liquid-liquid microextraction (DLLME) with in situ acetylation was successfully applied for quantification of pesticide residues, bisphenols, musk fragrances and UV-filters. Matrix effects were influenced by the type of seafood, with the lowest effects being observed with EMR-lipid and graphitized carbon black sorbents in dispersive solid-phase extraction cleanup step. Method performance features were successful evaluated in the different seafood samples - algae, mussel, lean and fatty fish muscles, following the criteria established by SANTE/12682/2019 for analytical methods for pesticide residues analysis. The detection and quantification of bisphenol F, musk fragrances (galaxolide and tonalide), UV-filters (2-ethylhexyl salicylate, 2-ethylhexyl 4-methoxycinnamate, and isoamyl 4-methoxycinnamate), and residues of permethrin in commercial samples of algae, mussel and fish collected in a Portuguese estuary support the suitability of the proposed method for future seafood monitoring by food safety authorities.

Exploring miniaturized sample preparation approaches combined with LC-QToF-MS for the analysis of sulfonamide antibiotic residues in meat- and/or egg-based baby foods.

Miniaturized and simplified sample preparation methods with reduced consumption of chemicals and non-halogenated solvents are presented for the determination of 12 sulfonamides in baby foods. Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was used for the identification and quantification of the compounds based on the acquisition of full spectrum at high resolution with accurate mass for precursor and its fragment ions. Three miniaturized protocols based on QuEChERS, salting-out assisted liquid-liquid extraction or low-temperature cleanup were evaluated regarding the extraction efficiency and removal capability of matrix co-extractives. All approaches achieved satisfactory recoveries (70.0-120.0%); however, the miniaturized QuEChERS distinguished by lower co-extractives content in the final extract providing lower matrix effects. Thus, the performance characteristics of the miniaturized QuEChERS were established using different matrices: beef-, egg yolk- and vegetable-based baby food or chicken- and vegetable-based baby food, in compliance with the Codex Alimentarius Commission guidelines. The target compounds were investigated in 30 commercial baby foods.

Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry as a potential combination for the determination of sulfonamide residues in complex infant formula matrices.

An accurate, sensitive and selective analytical method is proposed for sulfonamide residues analysis in infant formulas based on hydrophilic interaction liquid chromatography (HILIC) and quadrupole time-of-flight mass spectrometry in full scan mode. The sample preparation approach involves low-temperature lipid precipitation followed by dispersive solid-phase extraction with PSA and C18 sorbents, which was successfully optimized using Plackett-Burman design. In order to achieve high analytical sensitivity, the influence of HILIC conditions on sulfonamide ionization was investigated, such as the mobile phase composition, buffer concentration, and sample diluent for injection. The method performance characteristics, including linearity (range 5-120 µg kg-1), reliable limits of quantification (between 5 and 20 µg kg-1), recovery (72.9-109.2%) and precision (coefficient of variation values ≤ 19.8%) under repeatability and within-laboratory reproducibility conditions, were in accordance with the Codex Alimentarius Commission CAC/GL 71-2009 for quantitative analytical methods for veterinary drug residues in foods. Moreover, adequate identification of the compounds was provided with accurate mass measurement of both precursor and fragment ions in one single run. Finally, the developed method was applied to thirty-five powdered milk-based infant formula samples available in the Brazilian market.

Multivariate optimization of extraction and validation of phenolic acids in edible mushrooms by capillary electrophoresis.

A "green" analytical method is reported for the determination of phenolic acids in mushrooms. The sample preparation involves aqueous extraction based on acid hydrolysis, followed by analysis of extracts by capillary electrophoresis with diode array detector (CE-DAD). A central composite design was used to obtain the optimum conditions for the extraction of compounds from mushrooms, including the concentration of hydrochloric acid (2 mol·L-1), temperature (80 °C) and time (30 min). The proposed method avoids organic solvents such as methanol and acetonitrile commonly used as extraction solvent and/or mobile phase in studies on bioactive compounds in plant-based matrices by high-performance liquid chromatography, thus contributing to lower environmental impact. The validated CE-DAD method was applied to 42 samples of edible mushrooms, including the species Agaricus bisporus (white button mushroom and brown portobello), Lentinula edodes (shiitake), Pleurotus ostreatus (white oyster mushroom, hiratake and shimeji) and Pleurotus ostreatoroseus (pink oyster mushroom). The phenolic compounds homogentisic acid, cinnamic acid and p-coumaric acid were detected in the samples harvested in two seasons - summer and winter - with cinnamic acid reported as the major compound (levels between 53.88 and 440.42 mg·kg-1). Therefore, edible mushrooms have proved to be an alternative source of phenolic compounds.

Gas chromatography-mass spectrometry determination of polycyclic aromatic hydrocarbons in baby food using QuEChERS combined with low-density solvent dispersive liquid-liquid microextraction.

A sensitive GC-MS method is reported for the determination of twelve polycyclic aromatic hydrocarbons (PAHs) in baby food. The sample preparation involves QuEChERS extraction combined with low-density solvent dispersive liquid-liquid microextraction (LDS-DLLME) and ultra-low temperature (-80 °C). Plackett-Burman screening design was employed to identify the main sample preparation variables that affect the extraction efficiency, such as the volume of toluene used in LDS-DLLME. The suitability of proposed method was verified by analytical selectivity, linearity in solvent and matrix-matched calibration curves and adequate recoveries (72-112%) and precision (RSD values ≤11%), under repeatability and within-laboratory reproducibility conditions. High analytical sensitivity was achieved for the monitoring of PAHs at the strict limit of 1 µg kg-1 fixed by the European Commission for baby foods. The validated method was applied to thirty-two commercial baby food samples, and the investigated PAHs were not detected in any sample.

Simultaneous determination of acrylamide and 4-hydroxy-2,5-dimethyl-3(2H)-furanone in baby food by liquid chromatography-tandem mass spectrometry.

A liquid chromatography triple quadrupole mass spectrometry method was developed and validated for the simultaneous determination of acrylamide and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) in baby food. The sample preparation involves acetonitrile-based extraction combined with dispersive primary secondary amine (PSA) cleanup and cation-exchange solid-phase extraction (SPE), which promotes efficient removal of matrix interferences. Analytical selectivity and sensitivity were achieved for the quantification of acrylamide and HDMF in complex matrices such as fruit, cereal and milk-based baby foods; furthermore, adequate linearity (range 10-300µgkg-1) in solvent and matrix-matched calibration curves, and appropriate recoveries (94-110%) and precision (RSD≤10%), under repeatability and within-laboratory reproducibility conditions, were also obtained. Expanded measurement uncertainty was estimated at the 20µgkg-1 level (limit of quantification) on the basis of data obtained from in-house validation, with values of 25.5 and 16.5% for acrylamide and HDMF, respectively. The fitness for purpose of developed method was verified by analyzing 15 commercial baby foods available in the Brazilian market. Acrylamide was detected in one plum-based baby food (35µgkg-1) while HDMF in 67% of the samples analyzed (levels between 25 and 262µgkg-1).

Comparison of green sample preparation techniques in the analysis of pyrethrins and pyrethroids in baby food by liquid chromatography-tandem mass spectrometry.

A new selective and sensitive liquid chromatography triple quadrupole mass spectrometry method was developed for simultaneous analysis of natural pyrethrins and synthetic pyrethroids residues in baby food. In this study, two sample preparation methods based on ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) and salting-out assisted liquid-liquid extraction (SALLE) were optimized, and then, compared regarding the performance criteria. Appropriate linearity in solvent and matrix-based calibrations, and suitable recoveries (75-120%) and precision (RSD values≤16%) were achieved for selected analytes by any of the sample preparation procedures. Both methods provided the analytical selectivity required for the monitoring of the insecticides in fruit-, cereal- and milk-based baby foods. SALLE, recognized by cost-effectiveness, and simple and fast execution, provided a lower enrichment factor, consequently, higher limits of quantification (LOQs) were obtained. Some of them too high to meet the strict legislation regarding baby food. Nonetheless, the combination of ultrasound and DLLME also resulted in a high sample throughput and environmental-friendly method, whose LOQs were lower than the default maximum residue limit (MRL) of 10µgkg-1 set by European Community for baby foods. In the commercial baby foods analyzed, cyhalothrin and etofenprox were detected in different samples, demonstrating the suitability of proposed method for baby food control.

Optimisation of a sample preparation method for the determination of fumonisin B(1) in rice.

A simple, rapid and cost-effective sample preparation method for the determination of fumonisin B1 in rice was optimised using a strategy of sequential experimental designs. Initially, a Plackett-Burman design was applied to select the statistically significant variables for the determination of fumonisin B1, and then, a central composite rotatable design was used to define the optimal conditions of these variables. The method involves extraction with a 50% acetonitrile aqueous solution and glacial acetic acid, liquid-liquid partitioning with addition of anhydrous sodium sulphate and sodium chloride, followed by dispersive SPE clean-up with diatomaceous earth. The final extract was analysed by HPLC-FLD after precolumn derivatisation with ortho-phthaldialdehyde. The optimised method was validated for selectivity, linearity, matrix effect, limits of detection and quantification, trueness, and precision, and then applied to commercial samples of polished rice. This is the first report of the occurrence of fumonisin B1 in commercial samples of polished rice from the Southeast region of Brazil.

Monitoramento da concentração de íons fluoreto na água destinada ao consumo humano proveniente de um município com diferentes sistemas de abastecimento público / Monitoring the fluoride ions concentration in water for human consumption from a municipality with different public water supply systems

No presente estudo foram avaliadas as concentrações de íons fluoreto em amostras de água destinada ao consumo humano em um município com diferentes sistemas de abastecimento público. Em 139 amostras coletadas no ponto de entrada das edificações, no período de 2003 a 2007, foram determinadas as concentrações de íons fluoreto por meio de eletrodo combinado seletivo para flúor. As concentrações em conformidade com o padrão estadual (0,6 a 0,8 mg/L) foram detectadas em 87 (62,6) amostras e as proporções de conformidade aumentaram de 46,9 para 71,9 durante o período do estudo. As variações consideráveis nessas proporções, assim como nas concentrações mínimas e máximas, foram verificadas tanto em um mesmo sistema bem como entre diferentes sistemas de abastecimento de água. Os dados obtidos neste estudo indicam a necessidade de elaboração de planos de amostragem individualizados para cada sistema ou, ainda, a implantação de outra estratégia para efetuar o monitoramento da fluoretação da água em municípios com diferentes sistemas públicos de abastecimento de água para consumo humano.

Ciclamato de sódio em refrigerantes de baixa caloria / Sodium cyclamate in low calorie soft drinks

O objetivo deste estudo foi determinar os teores de ciclamato de sódio nos refrigerantes de baixa caloria mais consumidos no país. Os refrigerantes de baixa caloria dos tipos cola, guaraná, laranja, limão e uva foram analisados seguindo-se a técnica descrita por Sjõberg e Alanko (1987), com algumas modificações. Os ensaios de recuperação da metodologia foram realizados em três níveis de fortificação, com recuperação média de 92,5 e 110,3, respectivamente, para cola e guaraná, e o desvio-padrão relativo foi de 3,7. Os teores médios de ciclamato de sódio variaram de 27,1 ± 1,1 (cola A) a 127,3 ± 1,5 mg.100 mL-1 (limão B), o que mostra que a ingestão diária aceitável do edulcorante pode ser facilmente excedida com o consumo de refrigerantes de baixa caloria. Todas as amostras de refrigerantes apresentaram teores de ciclamato de sódio superiores àqueles indicados no rótulo, com 12,9 (cola A) a 19,0 (limão B) acima do declarado. Dos 18 refrigerantes analisados, apenas quatro apresentaram teor médio de ciclamato de sódio de acordo com o limite máximo de 40 mg.100 mL-1 de bebida, permitido pela legislação brasileira; e os demais apresentaram variação de 74,8 (laranja) a 218,3 (limão B) acima do limite permitido.