Multiresidue determination of pesticides in malt beverages by capillary gas chromatography with mass spectrometry and selected ion monitoring

Understanding How Chemical Pollutants Arise and Evolve in the Brewing Supply Chain: A Scoping Review

In this study, a critical review was carried out using the Web of ScienceTM Core Collection database to analyse the scientific literature published to date to identify lines of research and future perspectives on the presence of chemical pollutants in beer brewing. Beer is one of the world's most popular drinks and the most consumed alcoholic beverage. However, a widespread challenge with potential implications for human and animal health is the presence of physical, chemical, and/or microbiological contaminants in beer. Biogenic amines, heavy metals, mycotoxins, nitrosamines, pesticides, acrylamide, phthalates, bisphenols, microplastics, and, to a lesser extent, hydrocarbons (aliphatic chlorinated and polycyclic aromatic), carbonyls, furan-derivatives, polychlorinated biphenyls, and trihalomethanes are the main chemical pollutants found during the beer brewing process. Pollution sources include raw materials, technological process steps, the brewery environment, and packaging materials. Different chemical pollutants have been found during the beer brewing process, from barley to beer. Brewing steps such as steeping, kilning, mashing, boiling, fermentation, and clarification are critical in reducing the levels of many of these pollutants. As a result, their residual levels are usually below the maximum levels allowed by international regulations. Therefore, this work was aimed at assessing how chemical pollutants appear and evolve in the brewing process, according to research developed in the last few decades.

Comprehensive Review on Monitoring, Behavior, and Impact of Pesticide Residues during Beer-Making

This paper reviews the impact of beer-making stages (malting, mashing, boiling, and fermentation) on the behavior of pesticide residues. The large use of pesticides on barley and hop could cause the occurrence of their residues in beer. The foremost factors influencing the stability of residues (pH, temperature, and water content) and the physical-chemical properties of pesticides (octanol-water partition coefficient, vapor pressure, and water solubility) are essential to know their final fate. Most pesticides show a decrease in the unhopped wort because they are adsorbed onto the spent grains after mashing. In addition, their concentrations decrease during boiling and fermentation. Generally, maltsters should dedicate particular attention to the residues of hydrophobic pesticides because they can remain on the malt. Contrarily, brewers should control residues of hydrophilic pesticides because they can be carried over into young beer, disturbing the quality and organoleptic properties (flavor, aroma, taste, or color) of the beer.

Gold-based immunochromatographic strip assay for detecting dimethomorph in vegetables

Gold-based immunochromatographic strip assay for detecting dimethomorph in vegetables.

Magnetic solid-phase extraction based on magnetic amino modified multiwalled carbon nanotubes for the fast determination of seven pesticide residues in water samples

A rapid and simple analytical method based on magnetic solid-phase extraction with magnetic amino modified multiwalled carbon nanotubes with ultra-high performance liquid chromatography-tandem mass spectrometry is reported for the determination of seven pesticides (futriafol, metalaxyl, myclobutanil, napropamide, epoxiconazole, fipronil and diniconazole) in water samples. In this study, magnetic amino modified multi-walled carbon nanotubes were synthesized and selected as a new kind of material to adsorb pesticides in the water samples. Various magnetic solid-phase extraction parameters, such as the amount and type of adsorbent, extraction methods, extraction time, the type and volume of desorption solvent, desorption time and solution ionic strength, were systematically optimized. Under optimum conditions, the method validation results showed good linearity and recoveries. The calibration curves were in the range of 1.0-100 ng mL-1 for napropamide, epoxiconazole, metalaxyl, and fipronil, while they were 5.0-500 ng mL-1 for futriafol, myclobutanil, and diniconazole, with determination coefficients (R2) higher than 0.9909. The limits of quantification were 1.0-5.0 ng mL-1 and the limits of detection were 0.3-1.5 ng mL-1. The recoveries of the seven pesticides ranged from 80.4% to 103.2%. This developed method, which is more convenient and effective in comparison with traditional methods, has been successfully applied for the analysis of pesticides in water samples qualitatively and quantitatively.

Click Reaction-Mediated T2 Immunosensor for Ultrasensitive Detection of Pesticide Residues via Brush-like Nanostructure-Triggered Coordination Chemistry

We develop an ultrasensitive T₂-mediated immunosensor based on the coordination chemistry and Cu(I)-catalyzed 1,3-dipolar cycloaddition of azide andalkyne (CuAAC) and apply it for the detection of pesticide residues. We functionalize polyglutamic acid (PGA) on polystyrene to form a brush-like nanostructure that has a large loading capacity of Cu(II) through the coordination chemistry between PGA and Cu(II). Such a brush-like nanostructure could be used to chelate Cu(II) to modulate the CuAAC between azide-functionalized 1000 nm polystyrene (PS₁₀₀₀) and alkyne-functionalized 30 nm magnetic nanoparticles (MNP₃₀), and the MNP₃₀-PS₁₀₀₀ conjugate as a product of CuAAC can act as a magnetic probe in this T₂-based immunosensor. This click chemistry and coordination chemistry-mediated immunosensor allows for an ultrasensitive detection for chlorpyrifos residue (0.022 ng/mL), a 58-fold enhancement compared with that of enzyme-linked immunosorbent assay (1.28 ng/mL), providing a promising platform for detection of trace small molecules.

Residue dynamics of pyraclostrobin in peanut and field soil by QuEChERS and LC-MS/MS

A modified QuEChERS-LC-MS/MS (acronym of quick, easy, cheap, effective, rugged and safe-liquid chromatography tandem mass spectrometry) method for the analysis of pyraclostrobin residue in peanut and soil was developed and validated. Pyraclostrobin residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in peanut and soil were studied. The limits of quantitation (LOQs) for pyraclostrobin in soil, plant, shell and peanut samples were 0.00057, 0.00026, 0.003 and 0.0037 mg kg(-1), respectively. At fortification levels of 0.005, 0.05 and 0.5 mg kg(-1) in all samples, it was shown that recoveries ranged from 80.3% to 109.4% with relative standard deviations of 1.1-8.2% (n=5). The dissipation experiments showed the half-lives (T(1/2)) of pyraclostrobin in soil and plants were 13.1-16.5 days and 10.3-11.2 days, respectively. At pre-harvest intervals (PHI) of 14, 21 and 28 days, pyraclostrobin residue were 0.005-0.20 mg kg(-1) in soil, 0.006-0.27 mg kg(-1) in plants, below 0.053 mg kg(-1) in shells and not detectable in peanuts.

Studies on the supramolecular interaction between dimethomorph and disulfide linked β-cyclodextrin dimer by spectrofluorimetry and its analytical application

The supramolecular interaction of disulfide linked β-cyclodextrin (β-CD) dimer and dimethomorph has been studied by spectrofluorimetry. Based on the significant enhancement of the fluorescence intensity of dimethomorph, a new spectrofluorimetric method with high sensitivity and selectivity was developed for the determination of dimethomorph in bulk aqueous in the presence of the disulfide linked β-CD dimer. The inclusion complexation behavior of β-CD dimer with dimethomorph was studied in a KH(2)PO(4)-H(3)PO(4) buffer solution of pH 3.86 at room temperature. The apparent association constant of the complex was 2.25 × 10(4) L/mol. The linear range was 12-7500 ng/mL with the detection limit 3.70 ng/mL, and the limit of quantification was 12.4 ng/mL. The proposed method had been successfully applied to the determination of dimethomorph residues in vegetables with recoveries of 89.0-115%.

Hapten synthesis, monoclonal antibody generation, and development of competitive immunoassays for the analysis of picoxystrobin in beer

This paper describes the original synthesis of a functionalized derivative of the fungicide picoxystrobin and the generation of the first reported monoclonal antibodies against this strobilurin pesticide. The synthetic hapten was prepared by total synthesis from commercial chemicals and incorporating the spacer arm through a carbon-carbon single bond. Also, to obtain the immunogen, an uncommon hapten activation strategy based on N,N'-disuccinimidyl carbonate was employed, affording high activation yields and clean and reproducible coupling results. With these immunoreagents, two enzyme-linked immunosorbent assays (ELISAs) were developed: a competitive one-step assay using the antibody-coated direct ELISA format and a competitive two-step assay with the conjugate-coated indirect ELISA procedure. Both immunoassays were characterized in terms of sensitivity, selectivity, tolerance to solvents and matrix effects, achieving limits of detection below 0.2 μgL(-1). The optimized assays were used for the determination of picoxystrobin residues in beer, with recovery values ranging between 90 and 121% for the direct assay and from 79 to 122% for the indirect assay.

Multiresidue pesticide analysis of wines by dispersive solid-phase extraction and ultrahigh-performance liquid chromatography-tandem mass spectrometry

A multiresidue pesticide method is described for the determination of 72 pesticides in wines. Pesticides were extracted using acetonitrile saturated with magnesium sulfate and sodium chloride, followed by solid-phase dispersive cleanup using primary-secondary amine and graphitized carbon black sorbents. Analysis is performed by ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-MS/MS). The limits of quantitation (LOQs) for most of the pesticides ranged from 0.3 to 3.3 μg/L with the exception of cyromazine, fenhexamid, and acibenzolar S-methyl (LOQ > 10 μg/L), and quantitation was determined from calibration curves of standards containing 5.0-2500 μg/L with r(2) > 0.99. Recovery studies were performed by fortifying wine samples with the pesticides to concentrations of 10, 100, and 1000 μg/L, resulting in recoveries of >80% for most of the pesticides. Lower (<70%) and higher (>120%) recoveries were most likely from complications of pesticide lability or volatility, matrix interference, or inefficient desorption from the solid-phase sorbents. The method was used to analyze 10 wines collected from a market basket survey, and 19 different pesticides, primarily fungicides, were present at concentrations ranging from <1.0 to 1000 μg/L.

Trace level determination of selected organophosphorus pesticides and their degradation products in environmental air samples by liquid chromatography-positive ion electrospray tandem mass spectrometry

This paper describes a new analytical method for determination of organophosphorus pesticides (OPs) along with their degradation products involving liquid chromatography (LC) positive ion electrospray (ESI+) tandem mass spectrometry (MS-MS) with selective reaction monitoring (SRM). Chromatography was performed on a Gemini C6-Phenyl (150 mmx2.0 mm, 3 microm) with a gradient elution using water-methanol with 0.1% formic acid, 2 mM ammonium acetate mobile phase at a flow rate of 0.2 mL min(-1). The LC separation and MS/MS operating conditions were optimized with a total analysis time less than 40 minutes. Method detection limits of 0.1-5 microg L(-1) for selected organophosphorus pesticides (OP), OP oxon degradation products, and other degradation products: 3,5,6-trichloro-2-pyridinol (TCP); 2-isopropyl-6-methyl-4-pyrimidol (IMP); and diethyl phosphate (DEP). Some OPs such as fenchlorphos are less sensitive (MDL 30 microg L(-1)). Calibration curves were linear with coefficients of correlation better than 0.995. A three-point identification approach was adopted with area from first selective reaction monitoring (SRM) transition used for quantitative analysis, while a second SRM transition along with the ratio of areas obtained from the first to second transition are used for confirmation with sample tolerance established by the relative standard deviation of the ratio obtained from standards. This new method permitted the first known detection of OP oxon degradation products including chlorpyrifos oxon at Bratt's Lake, SK and diazinon oxon and malathion oxon at Abbotsford, BC in atmospheric samples. Atmospheric detection limits typically ranged from 0.2-10 pg m(-3).

Characterization of recovery profiles using gas chromatography-triple quadrupole mass spectrometry for the determination of pesticide residues in meat samples

The assessment of the recovery factor with the analyte concentration in meat samples has been studied for the determination of organochlorine and organophosphorus pesticides in meat by gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). For that purpose, recent IUPAC recommendations, which distinguishes between two terms, recovery factor and apparent recovery, have been followed. Besides, the systematic error due to the matrix effect has been evaluated by a new term recently proposed, calibration recovery. Recovery profiles were obtained analyzing spiked blank matrix, where the analytes were added before and after the extraction procedure. In a first step, the quantification of the compounds was carried out using a solvent calibration curve. The systematic errors due to the matrix effect during the quantification step and the error due to the sample treatment have been evaluated. Both apparent and calibration recovery components depend on the actual analyte concentration in the sample while the recovery factor remains constant except for analyte concentration close to quantification limit. In addition, the concentration limits, from which an acceptable recovery value (70-110%) can be obtained, are given. If spiked samples are quantified by matrix-matched calibration, the matrix effect is minimized and the calibration recovery component is 100%, and apparent recovery only depends on the recovery factor. The obtained values indicate recovery factor does not depend on the analyte concentration, except for those values closed to quantification limit.

Determination of carbofuran, carbaryl and their main metabolites in plasma samples of agricultural populations using gas chromatography–tandem mass spectrometry

A gas chromatography-tandem mass spectrometric (GC-MS/MS) method has been developed for the determination of carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate), carbaryl (1-naphthyl-N-methylcarbamate) and their main metabolites in human blood plasma. Optimization of the isolation of the compounds from plasma matrix included the precipitation, denaturation and digestion of plasma proteins. Derivatization was achieved by the use of trifluoroacetic acid anhydride and was optimized for temperature, time and volume of derivatization agent. In the proposed method, a mild precipitation technique was applied using beta-mercaptoethanol and ascorbic acid in combination with solid-phase extraction technique using Oasis HLB (Hydrophobic Lipophilic Balance) cartridges for further clean up of samples. Carbamate linkage was not hydrolyzed to its phenol product, but both carbamate phenol and ketones were transformed into trifluoroacetyl derivatives in order to become volatile compounds and were determined using tandem mass spectrometry. The linearity of the method was shown for nine concentrations in the range of 0.50-250 ng mL(-1) in fortified plasma aliquots. Limits of detection (LODs) for all compounds ranged from 0.015-0.151 ng mL(-1). Inter-day and intra-day assays (RSD) for all compounds, at three concentration levels of 2.5, 25 and 100 ng mL(-1) (n=3) in fortified plasma samples were less than 18%. Accuracy (%E (r)) was calculated at three concentration levels, 8, 80 and 160 ng mL(-1) (n=3), and ranged from -12.0 to 15.0%. Matrix effect was evaluated so mean recoveries were calculated for all compounds and ranged from 81-107%. Specificity for the use of this method to biological monitoring studies was achieved including four main metabolites of CF, 1-naphthol and 2-naphthol from the naphthalene metabolism pathways, and both the parent compound of carbofuran and carbaryl. The proposed method was applied to plasma samples of pesticide users.