Sample preparation and determination of pesticides in fat-containing foods

Overview of Liquid Sample Preparation Techniques for Analysis, Using Metal-Organic Frameworks as Sorbents

The preparation of samples for instrumental analysis is the most essential and time-consuming stage of the entire analytical process; it also has the greatest impact on the analysis results. Concentrating the sample, changing its matrix, and removing interferents are often necessary. Techniques for preparing samples for analysis are constantly being developed and modified to meet new challenges, facilitate work, and enable the determination of analytes in the most comprehensive concentration range possible. This paper focuses on using metal-organic frameworks (MOFs) as sorbents in the most popular techniques for preparing liquid samples for analysis, based on liquid-solid extraction. An increase in interest in MOFs-type materials has been observed for about 20 years, mainly due to their sorption properties, resulting, among others, from the high specific surface area, tunable pore size, and the theoretically wide possibility of their modification. This paper presents certain advantages and disadvantages of the most popular sample preparation techniques based on liquid-solid extraction, the newest trends in the application of MOFs as sorbents in those techniques, and, most importantly, presents the reader with a summary, which a specific technique and MOF for the desired application. To make a tailor-made and well-informed choice as to the extraction technique.

Simple and rapid ionic liquid-based one-, two-, three-phase transition microextraction for efficient extraction of trace organic pollutants and elimination of lipid co-extractives from fatty food matrices

Extraction of trace contaminants from fatty food matrices is challenging in food analysis. Herein, a new ionic liquid-based one-, two-, three-phase transition microextraction (IL-OTTPTME) was proposed to efficiently extract trace targets while simultaneously eliminating lipid co-extractives. The method performance was illustrated through the determination of chrysoidine in fatty soybean products using high-performance liquid chromatography-ultraviolet/visible detection. The strong interactions and infinite contact between IL and chrysoidine in the one-phase system ensured ultra-high extraction efficiency (∼100 %). Density functional theoretical calculations confirmed the presence of strong hydrogen bonding and π-π interactions. The formation of the three-phase system during extraction could completely eliminate lipid co-extractives. The IL-OTTPTME integrated extraction, enrichment and cleanup steps into one step, making it rapid and extremely easy to operate. The method had a wide linear range of 0.5-5000 μg/kg and low limit of detection (0.15 μg/kg). It also had satisfactory relative recoveries (95.1 %-104.0 %) and low RSDs (≤5.0 %, n = 5).

Pesticide residues in animal-derived food: Current state and perspectives

Pesticides are widely used in the cultivation and breeding of agricultural products all over the world. However, their direct use or indirect pollution in animal breeding may lead to residual accumulation, migration, and metabolism in animal-derived foods, posing potential health risks to humans through the food chain. Therefore, it is necessary to detect pesticide residues in animal-derived food using simple, reliable, and sensitive methods. This review summarizes sample extraction and clean-up methods, as well as the instrumental determination technologies such as chromatography and chromatography-mass spectrometry for residual analysis in animal-derived foods, including meat, eggs and milk. Additionally, we perspectives on the future of this field. This information aims to assist relevant researchers in this area, contribute to the development of ideas and novel technical methods for residual detection, metabolic research and risk assessment of pesticides in animal-derived food.

A Novel and Highly Efficient Microextraction Method for the Determination of Aflatoxin Precursor Averantin in Fatty Grain Samples

Averantin (AVN) is an important aflatoxin biosynthetic precursor and has been listed in the screening range of mycotoxins. Herein, a novel ionic liquid-based one-, two-, and three-phase transition microextraction (IL-OTTPTME) method was combined with high-performance liquid chromatography for the extraction and determination of AVN in fatty grain samples. The formation of a homogeneous solution and three-phase system during the IL-OTTPTME process allowed both efficient extraction and coextracted lipid cleanup. Density functional theory calculations and distribution coefficient determination results demonstrated that AVN extraction by IL mainly occurred through hydrogen-bond and π-π interactions. Under optimized conditions, the LOD and LOQ of the proposed method were 0.5 and 1.5 ng/g, respectively. Finally, the method was used to determine AVN in several grains with different fat contents, achieving satisfactory relative recoveries (86.0-107.8%) and RSDs (1.2-6.2%, n = 3).

Deep eutectic solvents in sample preparation and determination methods of pesticides: Recent advances and future prospects

This review summarizes recent advances of deep eutectic solvents (DESs) in sample preparation and determination methods of pesticides in food, environmental, and biological matrices since 2019. Emphasis is placed on new DES categories and emerging microextraction techniques. The former incorporate hydrophobic deep eutectic solvents, magnetic deep eutectic solvents, and responsive switchable deep eutectic solvents, while the latter mainly include dispersive liquid-liquid microextraction, liquid-liquid microextraction based on in-situ formation/decomposition of DESs, single drop microextraction, hollow fiber-liquid phase microextraction, and solid-phase microextraction. The principles, applications, advantages, and limitations of these microextraction techniques are presented. Besides, the use of DESs in chromatographic separation, electrochemical biosensors, fluorescent sensors, and surface-enhanced Raman spectroscopy are discussed. This review is expected to provide a valuable reference for extracting and detecting pesticides or other hazardous contaminants in the future.

Analysis of metabolome and transcriptome of longissimus thoracis and subcutaneous adipose tissues reveals the regulatory mechanism of meat quality in MSTN mutant castrated male finishing pigs

The underlying mechanism of myostatin (MSTN) gene mutation impact on porcine carcass and meat quality has not yet been fully understood. The meat quality trait testing of the second filial generation wild-type (WT) and homozygous MSTN mutant (MSTN-/-) castrated male finishing pigs, and RNA-seq and metabolomics on the longissimus thoracis (LT) and subcutaneous adipose tissues (SAT) were performed. Compared with WT pigs, MSTN-/- pigs had higher carcass lean percentage and lower backfat thickness (all P < 0.01), and also had lower shear force (P < 0.01) and meat redness (P < 0.05). The gene and metabolite expression profiles were different between two groups. Metabolites and genes related to purine metabolism (such as xanthine metabolite (P < 0.05), AMPD3 and XDH genes (all padj < 0.01)), PI3K/Akt/mTOR signaling pathway (such as Phe-Phe and Glu-Glu metabolites (all P < 0.05), WNT4 and AKT2 genes (all padj < 0.01)), antioxidant related pathway (such as GPX2, GPX3, and GPX7 genes (all padj < 0.01)), and extracellular matrix related pathway (such as COL1A1 and COL3A1 genes (all padj < 0.01)) were significantly altered in LT. While metabolites and genes associated to lipid metabolism (such as trans-elaidic acid and PE(18:1(9Z)/0:0) metabolites (all P < 0.05), ACOX1, ACAT1 and HADH genes (all padj < 0.01)) were significantly changed in SAT. This study revealed the biological mechanisms of homozygous MSTN mutation regulated porcine carcass and meat quality, such as lean meat percentage, fat deposition and tenderness, which provides reference for the utilization of MSTN-/- pigs.

Luminescent Probe Based on Terbium-Carbon Quantum Dots for the Quantification of Imidacloprid in Caneberries

We propose a modification of terbium-sensitized luminescence (TSL) by means of the introduction of nanoparticles to improve the sensitivity and selectivity of the analytical methods. TSL detection is usually based on the complexation between fluorescent organic compounds (the analytes) and terbium. The organic compound is then excited, and, after an energy transfer towards terbium, the latter emits the luminescence signal. Here, the modification consists of the introduction of nanoparticles (carbon quantum dots, CQDs) into the system. The carboxylic groups of CQDs react with terbium, providing an interesting time-resolved luminescence probe. We applied this system for the determination of the neonicotinoid imidacloprid (IMID). When IMID was introduced in the terbium-CQDs system, the luminescent signal (λexc/λem of 256/545 nm) was quenched, proportionally to IMID concentration in the range of 100-2500 ng·mL-1, obtaining a limit of detection of 30 ng·mL-1. A method detection limit of 0.9 mg·kg-1 was reached in caneberries, thus complying with the maximum residue level of 5 mg·kg-1 established by Codex Alimentarius. We performed recovery experiments in caneberries (blackberries, blueberries, raspberries, and mulberries), obtaining recovery yields close to 100% in all cases. These results show that the use of terbium ions-nanoparticles luminescence probes can be useful for screening purposes in quality control laboratories.

Development and application of a mini-QuEChERS method for the determination of pesticide residues in anuran adipose tissues

The expansion of monocultures to regions close to conservation areas has put biodiversity at risk, mainly due to the intense use of pesticides. Anurans are highly susceptible to pesticides and may be a biological marker in the contamination of an area. However, methods for determining pesticides in anurans are incipient. In this work, a miniaturized QuEChERS method was developed for the extraction of atrazine, chlorpyrifos, α- and β-endosulfan, α-, β-, θ- and ζ-cypermethrin in anuran adipose tissues. The method was optimized for the tissue sample size scale according to sample mass availability. Extracting solvent and adsorbents for the clean-up step was evaluated, achieving recoveries next to 100% with acetonitrile and without a clean-up step. The mini-QuEChERS method, using 500 mg of adipose tissue, 50 mg of NaCl and 200 mg of MgSO4, 100 μL of ultrapure water, and 1.50 mL of acetonitrile with no purification step, followed by high-performance liquid chromatography analysis and photodiode array detection was validated following the European Community guidelines. The methodology showed a moderate matrix effect for some pesticides, which was corrected using the matrix-matched calibration. The limits of quantification for the pesticide residues in adipose tissues ranged from 10 to 75 μg kg-1. Pesticide recoveries ranged from 74% to 115%, and repeatability and within-lab reproducibility showed relative standard deviations < 11%. The mini-QuEChERS method was applied to extract pesticide residues from the adipose tissues of two species of anurans: Leptodactylus macrosternum and Scinax x-signatus. 25% of samples were positive, detecting endosulfan and chlorpyriphos, confirmed by liquid chromatography coupled to tandem mass spectrometry. The mini-QuEChERS was a simple, economical, and eco-friendly method for extracting pesticide residues in anuran adipose tissue samples.

Analytical studies on some pesticides with antifungal effects: Simultaneous determination by HPLC, investigation of interactions with DNA and DNA damages

A simple, and fast method was developed for the simultaneous determination of five fungicides, namely thiram (THR), epoxiconazole (EPO), hexaconazole (HEX), tebuconazole (TEB), and diethofencarb (DIE), in different matrices by HPLC-UV. Parameters influencing the peak shape and resolution, such as the composition of mobile phase, pH and concentration of buffer solution, and column temperature, were examined and optimized. The proposed method was validated in terms of linearity, sensitivity, precision, and accuracy. Forced degradation studies were carried out for all analytes to demonstrate the specificity of the method and to evaluate the stability of analytes under different conditions. DNA interaction and DNA damage studies were conducted by HPLC and comet assay, respectively. All fungicides were found to bind DNA, except for DIE. While the binding coefficients for EPO, HEX, and TEB were of the order of 104, THR was found to interact more strongly with DNA with a binding coefficient of higher than 106. DIE did not induce DNA damage at any concentration tested. On the other hand, TEB, HEX, and EPO induced DNA damage up to 30 µg/mL. THR showed cytotoxic effects at 20 and 30 µg/mL and caused significant DNA damage at lower concentrations.

Analysis of Migrant Cyclic PET Oligomers in Olive Oil and Food Simulants Using UHPLC-qTOF-MS

Oligomers are a particular category of non-intentionally added substances (NIAS) that may be present in food contact materials (FCMs), such as polyethylene terephthalate (PET), and consequently migrate into foods. Here, an ultra-high-pressure liquid chromatography quadruple time-of-flight mass spectrometry (UHPLC-qTOF-MS) method was developed for the analysis of 1st series cyclic PET oligomers in virgin olive oil (VOO) following a QuEChERS clean-up protocol. Oligomer migration was evaluated with two different migration experiments using bottles from virgin and recycled PET: one with VOO samples stored in household conditions for a year and one using the food simulant D2 (95% v/v ethanol in water) at 60 °C for 10 days. Calibration curves were constructed with fortified VOO samples, with the LOQs ranging from 10 to 50 µg L^-1 and the recoveries ranging from 86.6 to 113.0%. Results showed no migration of PET oligomers in VOO. However, in the simulated study, significant amounts of all oligomers were detected, with the migration of cyclic PET trimers from recycled bottles being the most abundant. Additional substances were tentatively identified as linear derivatives of PET oligomers. Again, open trimer structures in recycled bottles gave the most significant signals.

Application of hollow fiber-protected liquid-phase microextraction combined with GC-MS in determining Endrin, Chlordane, and Dieldrin in rice samples

This paper introduces a novel and minimized sample preparation technique based on hollow fiber-protected liquid-phase microextraction that can be used in joint with gas chromatography-mass spectrometry (GC-MS) detection to extract three organochlorine pesticides-Endrin, Chlordane, and Dieldrin-from rice samples. To that end, a single-walled carbon nanotube (SWCNT) and a proper ionic liquid (IL) were ultrasonically dispersed and injected into the lumen of hollow fiber as the extraction phase for preconcentrating and extracting the target analytes from the rice samples. The effects of the type of nanoparticles, ILs, and desorption solvent on the efficiency of extracting the analytes were investigated based on the one-factor-at-a-time (OFAT) approach. In addition, other parameters influencing the extraction procedure were optimized using an experimental design that decreased the number of experiments, reagent consumption, and costs. Under optimized conditions, the limits of detection and quantification in determining mentioned pesticides varied between 0.019-0.029 and 0.064-0.098 ng mL-1, respectively. The calibration graphs to measure Endrin, Chlordane, and Dieldrin were linear over the concentration range of 0.064-13.2, 0.098-16.7, and 0.092-11.4 ng mL-1, respectively. The relative standard deviations for inter-day and intra-day analysis were below 7.06 and 4.75% for the triplicate determination of three organochlorine pesticides. Besides, the relative recoveries and standard deviations of Endrin, Chlordane, and Dieldrin for analyzing several Iranian rice samples were between 86.0-92.9% and 4.5-5.8%, respectively. The results were compared with other similar works in literature, proving that the proposed method is efficient and useful for routine monitoring of organochlorine compounds in food samples.

Organochlorine pesticides in vegetable oils: An overview of occurrence, toxicity, and chromatographic determination in the past twenty-two years (2000-2022)

Organochlorine pesticides (OCPs) are used globally to control pests in the food industry. However, some have been banned due to their toxicity. Although they have been banned, OCPs are still discharged into the environment and persist for long periods of time. Therefore, this review focused on the occurrence, toxicity, and chromatographic determination of OCPs in vegetable oils over the last 22 years (2000-2022) (111 references). Literature search shows that OCPs kill pests by destroying endocrine, teratogenic, neuroendocrine, immune, and reproductive systems. However, only five studies investigated the fate of OCPs in vegetable oils and the outcome revealed that some of the steps involved during oil processing introduce more OCPs. Moreover, direct chromatographic determination of OCPs was mostly performed using online LC-GC methods fitted with oven transfer adsorption desorption interface. While indirect chromatographic determination was favored by QuEChERS extraction technique, gas chromatography frequently coupled to electron capture detection (ECD), gas chromatography in selective ion monitoring mode (SIM), and gas chromatography tandem mass spectrometry (GC-MS/MS) were the most common techniques used for detection. However, the greatest challenge still faced by analytical chemists is to obtain clean extracts with acceptable extraction recoveries (70-120%). Hence, more research is still required to develop greener and selective extraction methods toward OCPs, thus improving extraction recoveries. Moreover, advanced techniques like gas chromatography high resolution mass spectrometry (GC-HRMS) must also be explored. OCPs prevalence in vegetable oils varied greatly in various countries, and concentrations of up to 1500 µg/kg were reported. Additionally, the percentage of positive samples ranged from 1.1 to 97.5% for endosulfan sulfate.

Multiresidue extraction of current-use pesticides from complex solid matrices using energized dispersive guided extraction with analysis by gas and liquid chromatography tandem mass spectroscopy

The development of sample processing techniques that recover a broad suite of pesticides from solid matrices, while mitigating coextracted matrix interferences, and reducing processing time is beneficial for high throughput analyses. The objective of this study was to evaluate the effectiveness of an automated extraction system for pesticide analyses in solid environmental samples. An Energized Dispersive Guided Extraction (EDGE) system was used to evaluate two different extraction solvents in optimizing the extraction of 210 pesticides and pesticide transformation products. A graphitized carbon cleanup step was implemented, and three elution solvents were evaluated separately for analyte recoveries. Recoveries between 70 and 130% were achieved for 167 compounds in a test soil using acetonitrile as an extraction solvent and carbon cleanup with acetonitrile and dichloromethane elutions. Nine field samples (soil, sediment, and biosolids) were extracted using the newly developed method and were compared with a previously validated pressurized liquid extraction (PLE) method using an Accelerated Solvent Extraction (ASE) system. Concentrations obtained from the two methods were comparable (linear R² > 0.999), suggesting similar performance between the EDGE and PLE extractions in complex matrices. The new method provided slightly better sensitivities in comparison to the PLE method, ranging from 0.09 to 2.56 ng g^-1. The method presented here significantly reduces extraction setup and runtimes while also minimizing the volume of carcinogenic solvents (e.g., dichloromethane) used in the laboratory and presents a sensitive multiresidue method for a wide range of pesticides in solid matrices.

Wide-Scope Multi-residue analysis of pesticides in beef by gas chromatography coupled with quadrupole Orbitrap mass spectrometry

Increasing pesticide contamination in foods of animal origin has made the wide-scope multi-residue analysis of pesticides an international concern. By using 191 pesticides, this study investigates a sensitive and reliable method for multi-residue analysis of pesticides in beef to determine the extent of the application of this method. The QuEChERS method was employed to extract and purify the pesticides as C18 was utilized as the absorbents. Then, the purified pesticides were analysed using gas chromatography - quadrupole orbitrap mass spectrometry (GC-Q-Orbitrap-MS). The validation test results revealed that this method was satisfactorily sensitive since its screening detection limit (SDL) ranged from 0.2 to 100 µg∙kg^-1. The recovery tests implemented at three spiking levels, namely 100, 200, and 500 µg∙kg^-1, generated the results of 71.95 %-113.97 %, while the intra- and inter-day precisions were 0.27 %-17.94 %, indicating that this method had excellent accuracy and precision.

Development and validation of a modified QuEChERS method for extracting polychlorinated biphenyls and organochlorine pesticides from marine mammal blubber

The monitoring of legacy persistent organic pollutants (POPs) in blubber of key sentinel marine mammal species has been conducted using established techniques for decades. Although these methods for polychlorinated biphenyl (PCB) and organochlorine (OC) pesticide determination provide accurate and reproducible results, they possess some drawbacks in terms of cost, time, and a need for large volumes of toxic solvents. QuEChERS (quick, easy, cheap, effective, rugged, and safe) extractions may help address these issues, but have not been applied to marine mammal blubber/adipose. As such, our aim was to develop, validate, and apply a QuEChERS method for the extraction of PCB and OC contaminants in marine mammal blubber. First, we tested multiple solid-phase extraction and clean-up steps to find the approach that provided the cleanest extracts along with consistent and acceptable analyte recovery, accuracy, and precision. QuEChERS extractions followed by two enhanced matrix removal-lipid (EMR-lipid), one primary-secondary amine (PSA), and one silica gel clean-up showed the highest matrix removal and acceptable recoveries of spiked internal (62-97%) and external standards (61-94%). Solvent usage was reduced by ∼393% and extraction time was reduced by ∼25% (from 16 to 12 h). Next, the method was validated using standard reference material (SRM) NIST 1945. Recovery experiments on SRM (n = 5) showed acceptable recovery for 76% and 77% of PCBs and OC pesticides, respectively, and high precision for 73% and 69% of PCBs and OCs, respectively. Finally, the method was used on a set of southeast Greenland killer whales (n = 13), with previously published PCB and OC data. Bland-Altman plots indicated good agreement between QuEChERS and current-use methods for ΣPCBs and some OCs with no significant constant or proportional bias. These results demonstrate that this QuEChERS extraction method represents an effective, lower cost alternative to current-use extractions for PCBs and OCs in blubber, and likely other high-lipid samples.

QuEChERS-based analytical methods developed for LC-MS/MS multiresidue determination of pesticides in representative crop fatty matrices: Olives and sunflower seeds

Oilseed crops are greatly extended all over the world. Their high fat content can interfere during pesticide multiresidue analysis through liquid chromatography-tandem mass spectrometry (LC-MS/MS). This work aimed at overcoming this issue by developing and validating two QuEChERS-based methods for LC-MS/MS determination of 42 pesticides in two fatty food matrices: olives and sunflower seeds. Optimization of the extraction method was achieved following a 2^6-2 fractional factorial design in a highly cost-effective way. Validation of the multi-residue methods demonstrated improved limits of detection, below the established maximum residue levels (MRLs) for almost all compounds, good precision, and trueness, in compliance with SANTE guidelines. Application of these methods to the analysis of real samples from the Iberian Peninsula showed the presence of some pesticides of relevant environmental concern, including four compounds contained in the Pesticide Action Network International list of highly hazardous pesticides, found at levels between 0.03 ng/g and 104 ng/g.

Magnetic polymer particles as a highly efficient and facile cleanup adsorbent for multi-pesticide residues analysis in aquatic products

A novel and efficient sample pretreatment procedure using magnetic particles was exploited for the determination of multi-pesticide residues in aquatic products. The magnetic adsorbent was prepared using divinyl benzene and N-vinyl pyrrolidone as functional monomers modified on the Fe₃O₄ @SiO₂. The obtained magnetic adsorbent, octadecylsilane sorbents, and graphitized carbon black were employed as effective adsorbents to remove matrix interferences in aquatic products, and their dosages were optimized. Satisfactory levels of accuracy and precision were procured under optimum conditions. The method limits of quantification ranged from 0.1 to 2.0 μg/kg. The analytical accuracy of the developed method for the analysis of multi-pesticide residues in freshwater and seafood products was validated. It was found to be suitable for the analysis of multi-pesticide residues in different types of aquatic products. Additionally, the method was successfully applied for the analysis of pesticide residues in fish samples obtained from aquaculture plants located in Zhejiang Province, China. The detected concentrations of pesticides ranged from 0.14 to 0.95 μg/kg. In general, this method shows promising application prospects for the rapid determination of multi-pesticide residues in aquatic products.

Current Role of Mass Spectrometry in the Determination of Pesticide Residues in Food

The extensive use of pesticides represents a risk to human health. Consequently, legal frameworks have been established to ensure food safety, including control programs for pesticide residues. In this context, the performance of analytical methods acquires special relevance. Such methods are expected to be able to determine the largest number of compounds at trace concentration levels in complex food matrices, which represents a great analytical challenge. Technical advances in mass spectrometry (MS) have led to the development of more efficient analytical methods for the determination of pesticides. This review provides an overview of current analytical strategies applied in pesticide analysis, with a special focus on MS methods. Current targeted MS methods allow the simultaneous determination of hundreds of pesticides, whereas non-targeted MS methods are now applicable to the identification of pesticide metabolites and transformation products. New trends in pesticide analysis are also presented, including approaches for the simultaneous determination of pesticide residues and other food contaminants (i.e., mega-methods), or the recent application of techniques such as ion mobility–mass spectrometry (IM–MS) for this purpose.

Ethanol-ammonium sulfate system based modified quick, easy, cheap, effective, rugged and safe method for the determination of four neonicotinoid pesticide and metabolite residues in two canned fruits

As the pesticide and its metabolite residues in processed fruits could become a significant route of human exposure. The work presented herein focuses on developing a feasible quick, easy, cheap, effective, rugged and safe method with improved extraction and cleanup system for the determination of imidacloprid, acetamiprid, thiamethoxam and clothianidin (metabolite of thiamethoxam) in canned fruits. The low toxic solvent ethanol was used to extract the analytes, and ammonium sulfate was used to promote the phase separation. Moreover, the carboxylated multi walled carbon nanotube was acted as the clean-up sorbent for removal of high solubility impurities. The proposed method was validated with fortified real samples at different concentration levels (20∼200 μg kg^-1 ). Recoveries obtained from three spiked levels (20, 50, 200 μg kg^-1 ) were ranged from 74.9% to 86.4% with relative standard deviations of the intra-day and inter-day in the range of 0.8 to 5.5% and 2.0 to 7.1%, respectively. Limit of detections were ranged from 0.2 to 0.5 μg kg^-1 and 0.2 to 0.6 μg kg^-1 for orange and peach, respectively. The results demonstrated that the proposed method could be considered appropriate, comparatively lower toxic for the analysis of neonicotinoid pesticide residues in canned fruit. This article is protected by copyright. All rights reserved.

Residual levels of five pesticides in peanut oil processing and chips frying

BACKGROUND

Pesticide contamination in oil crops and processed products is an important food safety concern. The study was aimed to investigate the pesticide residue changes in press processing of peanut oil and frying of chips.

RESULTS

Five pesticides - chlorpyrifos, deltamethrin, methoxyfenozide, azoxystrobin and propargite - which are often applied during growth period in peanut plants, were selected to investigate their residue changes in cold press processing of peanut oil and frying of potato chips. Results showed that the residues of the five pesticides were decreased by 3.1-42.6% during air-drying before oil pressing. The residues of chlorpyrifos, deltamethrin, methoxyfenozide and propargite in peanut oil were 2.05-3.63 times higher than that in peanut meal after cold pressing of the oil, except for azoxystrobin having a slightly lower residue in peanut oil, with 0.92 times that in peanut meal. The processing factors of the five pesticides in peanut oil ranged from 1.17 to 2.73 and were highly related to the log K_ow of the pesticides. The higher the log K_ow , the more easily was the pesticide partitioned in the peanut oil. Besides, as frying time increase during preparation of chips, the concentration of pesticides in peanut oil decreased gradually by 6.7-22.1% compared to the first frying. In addition, 0.47-11.06% of the pesticides were transferred to the chips through frying with contaminated oil.

CONCLUSION

This is first report showing that pesticides can transfer from contaminated oil to chips. There exists a potential dietary health risk by using pesticide-contaminated oil for frying chips. This work could provide basic data for accurate dietary risk assessment of pesticide residues in peanut oil and its frying products. © 2021 Society of Chemical Industry.

Simultaneous detection of ten kinds of insecticide residues in honey and pollen using UPLC-MS/MS with graphene and carbon nanotubes as adsorption and purification materials

An analytical method of simultaneous detection of ten insecticide residues in honey and pollen was established. The samples were purified with QuEChERS approach using new adsorbents and analyzed with UPLC-MS/MS. The results showed that both of graphene and carbon nanotubes were highly efficient adsorbents for the dSPE clean up to eliminate coextractives in the samples, and graphene was superior to carbon nanotubes for the detection of pesticide residues in honey and pollen samples. The proposed method was used to detect pesticide residues in 25 honey samples and 30 pollen samples which were randomly collected from more than ten provinces in China. All honey samples contain 1-27 μg/kg of chlorpyrifos residues. Only 4% of the honey samples were detected containing acetamiprid and imidacloprid, while the other seven pesticides were not detected. Chlorpyrifos residues were found in all pollen samples (5-66 μg/kg), among which twenty percent exceeded the maximum residue limits (MRLs, 50 μg/kg, European Commission Regulation). Most of the pollen samples containing pesticide concentrations higher than MRLs were collected from rape, followed by lotus, camellia, and rose. Besides, 36.7% and 33.3% of the pollen samples had imidacloprid and flupyradifurone higher than 5 μg/kg. A total of 26.7% pollen samples were detected containing bifenthrin, while none of the other six pesticides were detected in pollen samples.

Research and Application of In Situ Sample-Processing Methods for Rapid Simultaneous Detection of Pyrethroid Pesticides in Vegetables

A novel rapid and cost-effective pre-processing method for the simultaneous determination of pyrethroid pesticides in vegetables has been developed and validated. The process of pesticide extraction was carried out by the QuEChERS (quick, easy, cheap, effective, rugged and safe) method combined with filtration by filter paper, and cleanup was carried out by the multi-plug-filtration-cleanup (m-PFC) method with no centrifuge program during the whole process. The pre-processing method is optimized for gas chromatography (GC). The process is convenient and time saving, requiring just a few seconds per sample. The recovery rate (70–120%), limit of detection (0.0001–0.007 mg/kg), precision (0.2–9.3%) and accuracy for each analyte were determined in 10 representative vegetables with good results. Finally, the feasibility of the developed method was further confirmed by the successful determination of pyrethroid-pesticide residues in pyrethroid-containing practical samples within the processing method coupled with thin-layer chromatography and a colloidal-gold test strip.

Critical Evaluation of Analytical Methods for the Determination of Anthropogenic Organic Contaminants in Edible Oils: An Overview of the Last Five Years

Anthropogenic contaminants, as pesticides, polycyclic aromatic hydrocarbons (PAHs) and monochloropropanediols (MCPDs), have become important to be controlled in edible oils, since their regular occurrence. In fact, alerts from the Rapid Alert System for Food and Feed (RASFF) in oils normally include these compounds. From a critical point of view, tools used to control these compounds in the last 5 years will be discussed, including sample preparation, analysis and current regulations. Extraction and analysis methods will be discussed next, being liquid-liquid extraction (LLE) and QuEChERS, with or without clean-up step, as well as chromatographic methods coupled to different analyzers (mainly mass spectrometry), the most commonly used for extraction and analysis respectively. Occurrence in samples will also be reviewed and compared with the legal maximum residue limits (MRLs), observing that 4%, 20% and 60% of the analyzed samples exceed the legal limits for pesticides, MCPDs and PAHs respectively.

A Review on the Foodomics Based on Liquid Chromatography Mass Spectrometry

Due to the globalization of food production and distribution, the food chain has become increasingly complex, making it more difficult to evaluate unexpected food changes. Therefore, establishing sensitive, robust, and cost-effective analytical platforms to efficiently extract and analyze the food-chemicals in complex food matrices is essential, however, challenging. LC/MS-based metabolomics is the key to obtain a broad overview of human metabolism and understand novel food science. Various metabolomics approaches (e.g., targeted and/or untargeted) and sample preparation techniques in food analysis have their own advantages and limitations. Selecting an analytical platform that matches the characteristics of the analytes is important for food analysis. This review highlighted the recent trends and applications of metabolomics based on "foodomics" by LC-MS and provides the perspectives and insights into the methodology and various sample preparation techniques in food analysis.

Critical Assessment of Clean-Up Techniques Employed in Simultaneous Analysis of Persistent Organic Pollutants and Polycyclic Aromatic Hydrocarbons in Fatty Samples

Interference of residual lipids is a very common problem in ultratrace analysis of contaminants in fatty matrices. Therefore, quick and effective clean-up techniques applicable to multiple groups of analytes are much needed. Cartridge and dispersive solid-phase extraction (SPE and dSPE) are often used for this purpose. In this context, we evaluated the lipid clean-up efficiency and performance of four commonly used sorbents—silica, C18, Z-Sep, and EMR-lipid—for the determination of organic pollutants in fatty fish samples (10%) extracted using ethyl acetate or the QuEChERS method. Namely, 17 polychlorinated biphenyls (PCBs), 22 organochlorine pesticides (OCPs), 13 brominated flame retardants (BFRs), 19 per- and polyfluoroalkyl substances (PFAS), and 16 polycyclic aromatic hydrocarbons (PAHs) were determined in this study. The clean-up efficiency was evaluated by direct analysis in real time coupled with time-of-flight mass spectrometry (DART-HRMS). The triacylglycerols (TAGs) content in the purified extracts were significantly reduced. The EMR-lipid sorbent was the most efficient of the dSPE sorbents used for the determination of POPs and PAHs in this study. The recoveries of the POPs and PAHs obtained by the validated QuEChERS method followed by the dSPE EMR-lipid sorbent ranged between 59 and 120%, with repeatabilities ranging between 2 and 23% and LOQs ranging between 0.02 and 1.50 µg·kg⁻¹.

基于氧化石墨烯气凝胶固相萃取柱检测有机磷农药

以氧化石墨烯气凝胶三维纳米材料作为固相萃取的吸附剂,结合高效液相色谱,对食品中的有机磷农药(辛硫磷、双硫磷、倍硫磷、杀螟硫磷)进行检测分析。首先,利用冷冻干燥的方式制备得到氧化石墨烯气凝胶,通过扫描电镜、红外光谱、比表面积吸附等一系列的实验手段对其形貌及物理特性进行了表征,证明其成功合成。从扫描电镜中可见石墨烯的层状褶皱结构,其表面积为740.51 m²/g。然后,将氧化石墨烯气凝胶直接填充于固相萃取柱中,在未借助任何硅胶等基体的条件下进行萃取研究;通过单因素实验,系统研究了萃取和洗脱条件对有机磷农药萃取回收率的影响。结果显示,在上样体积15 mL、样品溶液pH值4、上样速率1.0 mL/min、洗脱剂1.0 mL乙腈的条件下萃取回收率最高。与商用的萃取材料进行比较,包括碳十八硅胶柱(C18)、阴离子交换柱(SAX)、氨基柱(-NH₂)和硅酸镁柱(Florisil),氧化石墨烯气凝胶填充的固相萃取柱的萃取回收率有明显提高。实验考察了氧化石墨烯气凝胶直接填充的萃取柱的寿命,结果显示该萃取柱可以重复使用15次,可见解决了分散无基体支撑的石墨烯纳米片容易破碎、堵塞筛板的问题。与液相色谱联用建立分析方法,4种有机磷农药的线性范围较宽,辛硫磷、双硫磷和倍硫磷的线性范围为1~200 μg/L,杀螟硫磷的线性范围为2~200 μg/L,线性拟合良好(线性相关系数r²≥0.9949),检出限为0.2~0.5 μg/L,满足于我国和其他国家限定标准的检测。将该方法应用于实际样品,在苹果皮中未检测到有机磷农药,对其进行加标,回收率为70.5%~93.6%,相对标准偏差≤10.4%。

QuEChERS sample preparation integrated to dispersive liquid-liquid microextraction based on solidified floating organic droplet for spectrometric determination of sudan dyes: A synergistic approach

In this project, a synergistic approach has been proposed where a quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation technique was developed for the extraction of sudan III and sudan IV dyes in different spices prior to its dispersive liquid-liquid microextraction based on solidified floating organic droplet (DLLME-SFO). Initially, the sample was extracted by QuEChERS method and then preconcentrated through DLLME-SFO followed by spectrophotometric detection. All the experimental parameters i.e., volume of extraction solvent, pH, acetonitrile to water ratio, temperature, centrifugation rate and time, and sample volume were optimized. Limit of detection (LOD) calculated for sudan III and sudan IV were 0.42 and 0.35 mg/L, respectively. Excellent recoveries were obtained in the range of 98.29-99.88%. After validation through standard addition methodology, the developed QuEChERS@DLLME-SFO method was successfully applied to determine sudan (III-IV) dyes in real spices samples. Integration of QuEChERS and DLLME-SFO was found to be a suitable substitute to eliminate the usage of costly primary secondary amines and other sorbents. The synergistic approach of QuEChERS and DLLME-SFO with the aid of UV/visible spectrophotometry makes it prompt, cost effective technique with excellent analytical figures of merit.

Applicability of Superheated Water Extraction for the Quantification of Pesticide Residues in Leafy Vegetables

Superheated water extraction (SWE) of pesticide residues in a cabbage sample was demonstrated. The recovery yields of several relatively polar pesticides (log P_ow < 3) by the spike-and-recovery method at 100°C were acceptable. Increasing the extraction temperature up to 150°C led to enhanced extraction efficiency except for pesticides that induced degradation. The recovery yields of some target pesticides having log P_ow values of 3.5 - 4 were effectively enhanced by increasing the number of extraction cycles. The observed concentration of fenitrothion in a cabbage sample was comparable with those by the official Japanese analytical method. These results suggested SWE is potentially suitable for the extraction of different relatively high-to-medium polarity pesticides.

A Combination of Chromatography with Tandem Mass Spectrometry Systems (UPLC-MS/MS and GC-MS/MS), Modified QuEChERS Extraction and Mixed-Mode SPE Clean-Up Method for the Analysis of 656 Pesticide Residues in Rice

The emerging ungovernable application of pesticides in rice farming has attracted public concerns as these hazardous chemicals leave long-lasting environmental impacts and cause severe health effects. Here, an optimized analytical method was proposed for the measurement of 656 pesticide residues in rice samples collected in Vietnam. We utilized chromatography with tandem mass spectrometry systems (UPLC-MS/MS and GC-MS/MS) combined with a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method and adopted a mixed-mode SPE clean-up method for the analysis. The results showed that a total of 341 and 315 compounds were determined by UPLC- and GC-MS/MS, respectively. Usage of 10 mL MeCN, 5 mL H₂O and 1% glacial acetic acid as extraction solvent outperformed other mixtures in purifying the analytes from the sample matrix. Besides, pressure swing adsorption connected to a C18 cartridge with C18 placed on top exhibited remarkably more extracted compounds of high recovery which resulted in 299 and 318 compounds with recovery ranging from 70 to 120% in GC- and UPLC-MS/MS, respectively. Our optimized protocols also resulted in maximal limits of quantification of 10 μg Kg⁻¹ in both MS methods with repeatability and reproducibility less than 20%. Application of validated method on 20 rice samples collected in Hanoi, Vietnam showed that 14 samples were contaminated with at least one pesticide, and insecticide was the most detected group. Overall, the compliance of all method validation parameters to SANTE/12682/2019 Guideline demonstrates that this protocol can be employed for the effective management of Vietnam’s rice in accordance with international requirements.

Recent Developments and Applications of Microfluidic Paper-Based Analytical Devices for the Detection of Biological and Chemical Hazards in Foods: A Critical Review

Nowadays, food safety has become a major concern for the sustainability of global public health. Through the production and distribution steps, food can be contaminated by either chemical hazards or pathogens, and the determination of these plays a critical role in the processes of ensuring food safety. Therefore, the development of analytical tools that can provide rapid screening of these hazards is highly necessary. Microfluidic paper-based analytical devices (µPADs) have advanced significantly in recent years as they are rapid and low-cost analytical screening tools for testing contaminated food products. This review focuses on recent developments of µPADs for various applications in the food safety field. A description of the fabrication of selected papers is briefly discussed, and evaluation of the μPADs' performance with regard to their precision and accuracy as well as their limits of detection is critically assessed. The advantages and disadvantages of these devices are highlighted.

Rapid Screening of 350 Pesticide Residues in Vegetable and Fruit Juices by Multi-Plug Filtration Cleanup Method Combined with Gas Chromatography-Electrostatic Field Orbitrap High Resolution Mass Spectrometry

A new method for screening pesticide residues in vegetable and fruit juices by the multi-plug filtration cleanup (m-PFC) method combined with gas chromatography-electrostatic field orbitrap high resolution mass spectrometry(GC-Orbitrap/MS) was developed. The samples were extracted with acetonitrile, purified with m-PFC and determined by GC-Orbitrap/MS. Qualitative analysis was confirmed by retention time, accurate molecular mass and quantitative analysis were performed with the matrix standard calibration. It could eliminate matrix interference effectively. Eight kinds of typical samples (orange juice, apple juice, grape juice, strawberry juice, celery juice, carrot juice, cucumber juice, tomato juice) were evaluated. The linear ranges of the 350 pesticides were from 5 to 500 μg/kg, with good correlation coefficients greater than 0.990. The limits of detection (LODs) were 0.3-3.0 μg/kg and the limits of quantification (LOQs) were 1.0-10.0 μg/kg. The average recoveries at three spiked levels of 10, 100, 200 μg/kg were in the range of 72.8-122.4%, with relative standard deviations (RSDs) of 2.0-10.8%. The method has effectively improved the determination efficiency of pesticide residue screening by high-resolution mass spectrometry in vegetable and fruit juices.

Development and validation of an analytical method for the multiresidue analysis of pesticides in sesame seeds using liquid- and gas chromatography with tandem mass spectrometry

For the first time, an analytical method for the multiresidue analysis of multiclass pesticides in sesame seeds using liquid- and gas chromatography with tandem mass spectrometry (LC-MS/MS and GC-MS/MS) was developed and validated. At first, the sample was comminuted after adding water (1:2 w/v). The sample preparation workflow included acetonitrile extraction, followed by freeze-out of the extract at -80°C with a subsequent cleanup by dispersive solid phase extraction (dSPE) (100 mg of C₁₈ + 150 mg of MgSO₄ for LC-MS/MS and 100 mg of C₁₈ + 25 mg florisil + 150 mg of MgSO₄ for GC-MS/MS). As noted, these cleanup steps were quite effective in removing the fatty co-extractives. The optimised sample preparation method effectively minimised the matrix effects and offered a limit of quantification (LOQ) of 0.01 mg/kg for most compounds. The LC-MS/MS and GC-MS/MS methods were validated at three levels (0.01, 0.02 and 0.05 mg/kg) for 222 and 220 compounds respectively. The method accuracy and precision complied with the performance criteria of the SANTE/12682/2019 analytical quality control procedure. The results of the intra-laboratory (involving six analysts) and inter-laboratory studies (involving eight accredited laboratories) were comparable for all pesticides. Considering its performance efficiency and alignment with the regulatory guidelines, this method can be implemented across the food testing laboratories for the monitoring of pesticide residues in sesame seeds.

Validation and Use of an Accurate, Sensitive Method for Sample Preparation and Gas Chromatography-Mass Spectrometry Determination of Different Endocrine-Disrupting Chemicals in Dairy Products

Endocrine disrupting chemicals (EDCs) are exogenous substances capable of altering the human hormone system and causing various diseases such as infertility and cancer as a result. In this work, a method for determining twenty-three different EDCs including parabens, alkylphenols, phenylphenols, organophosphorus pesticides, bisphenol A and triclosan in dairy products was developed. Samples are conditioned by addition of acetonitrile containing 1% formic acid, centrifugation and clean-up of the extract by continuous solid-phase extraction. EDCs in the extract are derivatised by heating in a microwave oven and quantified by gas chromatography-mass spectrometry. The proposed method features good limits of detection (6-40 ng/kg) and precision (relative standard deviation < 7.6%); also, it is scarcely subject to matrix effects (1-20%). EDC recoveries from spiked samples ranged from 80 to 108%. The method was used to analyse a total of 33 samples of dairy products including cow, sheep and goat milk, yoghourt, milkshakes, cheese, cream, butter and custard. Bisphenol A was the individual contaminant detected in the greatest number of samples, at concentrations from 180 to 4800 ng/kg. 2-Phenylphenol and ethylparaben were found in more than one-half, at concentrations over the range 130-3500 and 89-4300 ng/kg, respectively. In contrast, alkylphenols, organophosphorus pesticides and triclosan were detected in none.

Simultaneous determination of eight biogenic amines in the traditional Chinese condiment Pixian Douban using UHPLC-MS/MS

A UHPLC-MS/MS method was developed to simultaneously determine eight biogenic amines (BAs) in Pixian Douban. Under optimal conditions, the linear ranges of determination were 5-1000 μg/L (that of spermine was 8-1000 μg/L). Correlation coefficients ranged from 0.9955 to 0.9987. The limits of detection were 0.11-5.5 μg/L. The matrix effect and analytical performance of the present method were evaluated, and the eight BAs were analyzed by this method in 19 samples, indicating the potential pollution of BAs in chili oil Pixian Douban.

A multi-residue pesticide determination in fatty food commodities by modified QuEChERS approach and gas chromatography-tandem mass spectrometry

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) based multi-residue method has been developed and validated for the extraction and determination of pesticides in fatty matrices by gas chromatography tandem mass spectrometry. Extraction and clean-up were performed according to QuEChERS principles widely used for non-fatty matrices, with main difference, a higher solvent/sample- ratio followed by a 6-fold preconcentration step, ensuring good extractability and sensitivity. A validation according to SANTE guidelines was performed using a olive and sunflower oils mixture 1:1, w/w as representative matrix, at 2 concentration levels (5 and 50 µg/kg) targeting 176 GC-amenable pesticides. Most compounds fulfilled the validation criteria, with a limit of quantification of 5 µg/kg for 137 compounds , and of 50 µg/kg for 24 compounds. Afterwards, the method performance was tested in six different fatty matrices with 73-90% of the analytes fulfilling the performance criteria at 5 µg/kg depending on the matrix.

Highly-selective complex matrices removal via a modified QuEChERS for determination of triazine herbicide residues and risk assessment in bivalves

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERs) method for determining triazine herbicide residues in bivalves (Mussels, Scallops, Cockles) was developed. The use of molecularly imprinted polymers (MIPs) as a selective purification material during dispersive-solid phase extraction (d-SPE) increased the removal rate of pigments interference. With 4% acidic acetonitrile as the organic modifier, the modified QuEChERs method achieved good extraction rate of herbicide residues. The satisfactory recoveries (80%-118%) and RSDs (1.0%-11.6%) of herbicide residues were obtained at three spiked levels. The limits of quantification of herbicide residues ranged from 0.10 μg/kg to 1.59 μg/kg. Further, the herbicide residues in bivalves collected in the eastern coasts of China was analyzed. The developed QuEChERs procedure coupled with GC-MS/MS was successfully applied to the herbicide residues detection in bivalves, and due to the extensive use of herbicides and the large consumption of bivalves in globally, the ongoing risk evaluation is needed.

Application of blockchain technology in food safety control：current trends and future prospects

Blockchain technology is a distributed ledger technology and is expected to face some difficulties and challenges in various industries due to its transparency, decentralization, tamper-proof nature, and encryption security. Food safety has been paid increasing attention in recent years with economic development. Based on a systematic literature critical analysis, the causes of food safety problems and the state-of-the-art blockchain technology overview, including the definition of blockchain, development history, classification, structure, characteristics, and main applications, the feasibility and application prospects of blockchain technology in plant food safety, animal food safety, and processed food safety were proposed in this review. Finally, the challenges of the blockchain technology itself and the difficulties in the application of food safety were analyzed. This study contributes to the extant literature in the field of food safety by discovering the excellent potential of blockchain technology and its implications for food safety control. Our results indicated that blockchain is a promising technology toward a food safety control, with many ongoing initiatives in food products, but many food-related issues, barriers, and challenges still exist. Nevertheless, it is expected to provide a feasible solution for controlling food safety risks.

Monitoring of polar pesticides and contaminants in edible oils and nuts by liquid chromatography-tandem mass spectrometry

A single method was developed for the determination of polar pesticides (fosetyl-Al and its metabolite, phosphonic acid, and ethephon) and environmental contaminants (chlorate and perchlorate) in edible oils and nuts. Two extraction methods based on QuPPe-PO approach (Quick Polar Pesticides Method for products of Plant Origin) were optimized. In oils, a single extraction using water acidified with formic acid (1%) was performed, while in nuts, the clean-up step was modified. C18 was used as sorbent and an extra cleaning step with n-hexane was added. The extracts were analysed by liquid chromatography coupled to a triple quadrupole mass analyser (LC-QqQ-MS/MS). The method was validated and the limit of quantification was 0.01 mg kg^-1 for all analyte-matrix combination. Recoveries from 70 to 120%, and intra and inter-day precision values ≤20% were obtained. Forty samples of edible oils and nuts were analysed, detecting phosphonic acid in nuts at concentrations up to 4.6 mg kg^-1.