Multiresidue Analysis Of Pesticides Research Articles

Multi-residue analysis of pesticides and veterinary drugs by ultra-performance liquid chromatography-tandem mass spectrometry using a modified QuEChERS method

Multi-residue analysis of pesticides and veterinary drugs by ultra-performance liquid chromatography-tandem mass spectrometry using a modified QuEChERS method

Multi-residue determination of pesticides in star anise by a QuEChERS and gas chromatography tandem mass spectrometry-based method

ABSTRACT The star anise is a challenging substrate for pesticide residue analysis because of complex matrix interference. Efforts were made in this work to establish a robust method for analysis of pesticide multi-residues in the star anise. The Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for pretreatment of star anise was evaluated and optimised. By adopting the optimised matrix purification method, the content of non-volatile matrix co-extracts of star anise was reduced by 63% compared to the unpurified procedure. The matrix-matched calibration standards were used to reduce the influence of strong matrix effect. Combined with gas chromatography tandem mass spectrometry (GC­MS/MS) detection, residues of 227 pesticides in the star anise were validated. In the optimised method, 216 target substances (95% of total tested) obtained satisfactory recoveries (72–119%) and relative standard deviations (1–10%) at three spiking levels, and established a method limit of quantification (LOQ) of 0.05 mg kg−1. Moreover, the optimised method was successfully employed to analyse target pesticides in star anise market samples. The residues of tebuconazole, difenoconazole, methoprene, chlorpyrifos, propoxur and piperonyl butoxide were detected.

QuEChERS methodology and Gas Chromatography-mass spectrometry for detection of 345 pesticide residues in Egyptian poultry feed: a comprehensive study

Animal feed significantly influences the content and quality of animal products consumed by humans and plays a crucial role in the food chain. To simultaneously analyze 345 pesticide residues in poultry feed, a modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was developed, utilizing gas chromatography-tandem mass spectrometry (GC-MS/MS). Validation studies were conducted with spiked pesticide standards, and commercial poultry feed samples were analyzed. The linearity of the QuEChERS method was evaluated, showing high coefficients of determination (R 2 ≥0.995) for all analytes. The method demonstrated excellent linearity (R 2 ≥0.995), recovery rates (86.8–109.2%), and precision (RSD ≤14.8%), meeting SANTE criteria. Limits of detection (LOD) ranged from 0.5 to 5 ng/kg and limits of quantification (LOQ) from 1 to 10 ng/kg, enhancing the method’s reliability. Analysis of the poultry feed revealed that 15 out of the 345 pesticide residues were detected in the samples, with concentrations ranging from 2.1 to 120 µg/kg. The detected pesticide categories included insecticides, fungicides, plant growth regulators, and herbicides, in that order. In conclusion, the QuEChERS method combined with the GC-MS/MS approach provides a reliable technique for the multi-residue analysis of pesticides in complex feed matrices.

Maximizing sensitivity and selectivity in LC × LC-HRMS for pesticide analysis via exploitation of per-aqueous liquid chromatography

Accurate monitoring of pesticide residues at minimal concentrations is imperative for adherence to stringent regulatory standards in numerous countries. This study presents an innovative methodology employing comprehensive two-dimensional liquid chromatography coupled with high-resolution mass spectrometry (LC × LC-HRMS). The approach ensures high sensitivity and selectivity in detecting targeted compounds. A pivotal component of this methodology is the utilization of per-aqueous liquid chromatography (PALC) as the first dimension, facilitating the use of water-based mobile phases and addressing solvent mismatch issues. The second dimension employs reversed-phase liquid chromatography (RPLC), enhancing the separation of compounds. PALC proves instrumental in refocusing and enables the practical application of narrow-diameter columns (1.5 mm I.D.). This column design permits a direct split-free connection of the LC × LC to an electrospray-based mass spectrometer (ESI-MS), contributing to heightened sensitivity. The MS acquisition is performed in a targeted single-ion monitoring mode, ensuring reliable quantification and identification of the pesticide compounds. A comprehensive evaluation of key performance metrics, including signal-to-noise ratio, limit of detection, and response linearity, is conducted. The methodology achieves a limit of detection below the ng mL−1 and exhibits response linearity within the concentration range of 1–100 ng mL−1. The robustness of the approach is further demonstrated through intra-day and inter-day repeatability validations. Furthermore, the platform is finally tested on a surface water sample. This study not only introduces an advanced analytical methodology for pesticide multi-residue analysis but also underscores the significance of PALC in enhancing sensitivity by facilitating the use of smaller-diameter columns and water-based mobile phases, along with the role of RPLC in enhancing separation. The proposed approach showcases promising results in achieving detection limits that match the stringent regulatory standards and reliable quantification for effective pesticide residue monitoring.

Multiclass and multi-residue determination of pesticides and antibiotics in sediment from an aquacultural environment based on modified dispersive solid-phase extraction.

A quick, easy, cheap, effective, rugged, and safe method was developed for the multi-residue analysis of pesticides and antibiotics in aquaculture sediment using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The developed method is based on ultrasonic extraction with acetonitrile and phosphate buffer, salting with sodium chloride, and cleaning with dispersive solid-phase extraction adsorbent using primary secondary amine, C18, and graphitized carbon black, followed by HPLC-MS/MS detection. We optimized different extraction methods and the ratio of the cleanup adsorbents to achieve good recoveries at three spiking levels that ranged from 60.4% to 114% with a relative standard deviation below 15% (n=6). For all analytes, except for flufenoxuron, the limits of quantification were between 1 and 5µg/kg (dry weight). The validated method was successfully applied to real samples collected from 20 aquacultural ponds, confirming the feasibility of the proposed method. The concentrations of the target analytes in the sediments (dry weight) were in the ranges of 2.2-35.0µg/kg for sulfonamides, 0-409.1µg/kg for quinolones, 0-6.56µg/kg for macrolides, and 0-4.9µg/kg for pesticides. Moreover, the co-occurrence of pesticides and antibiotics may potentially pose a high risk to sediment-dwelling organisms in nine out of the 20 investigated locations.

Sustainable magnetic covalent organic framework materials for multi-residue analysis of pyrethroid pesticides in tobacco, fruits and vegetables

Magnetic covalent organic frameworks (MCOFs) materials were synthesized in deep eutectic solvents (DESs) instead of traditional toxic organic solvents under ambient conditions. The reaction time could be reduced to about 3 h, which was more than 12 h for the traditional synthesis method. Materials characterization indicated that the MCOFs materials with Tp and BD as monomer synthesized in ChCl-urea based DESs (i.e. Urea-MTpBD) showed good magnetic property and higher specific surface area. The Urea-MTpBD materials were used as a magnetic solid phase extraction (MSPE) sorbent for the enrichment and determination of 16 pyrethroid pesticides (PYs), coupled with GC-MS/MS technology. The effective enrichment of PYs with Urea-MTpBD materials was achieved, which was due to the synergistic effects of π-π stacking and hydrophobic interactions. The limits of detection (LODs) of 16 PYs with the developed method ranged from 2.15 to 5.67 ng/mL, while the recovery was between 70.99 % and 109.09 % with excellent intra-day and inter-day precisions (RSDintra ≤ 5.78 %, RSDinter ≤ 9.13 %). The developed method was applied successfully to determine 16 PYs in tobacco, fruits and vegetables. Furthermore, the Urea-MTpBD materials could be reused three times, which showed not only highly efficient, but also economical and sustainable.

Comparison of nitrogen and helium as carrier gases for determination of pesticide residues in foods via gas chromatography–tandem mass spectrometry with atmospheric pressure chemical ionization

The applicability of nitrogen as an alternative carrier gas to helium for the multiresidue analysis of pesticides using gas chromatography–tandem mass spectrometry with atmospheric pressure chemical ionization (GC–(APCI)MS/MS) was examined. The methods using both carrier gases were validated for 151 pesticides in foods at a spiking level of 0.01 ppm, maintaining identical conditions for both gases, including the GC column and carrier gas flow rate. The use of nitrogen resulted in slightly broader peaks and lower peak intensities that those observed upon using helium. However, sufficient sensitivity was achieved for all target compounds because of the high sensitivity of the GC–(APCI)MS/MS method. Further, target-compound separation was not significantly affected by the carrier gas type, and no interfering peaks were observed, demonstrating the high selectivity of the nitrogen-based method, even beyond the optimum linear velocity. Finally, the analytical performance of the nitrogen-based method was comparable to those of the helium-based method. Considering cost-effectiveness of nitrogen, this method is highly valuable in the event of helium shortages and for routine pesticide residue monitoring.

Higher early than late-season residue load of pesticides in honey bee bread in Slovakia

Bees are often exposed to pesticide residues during their foraging trips in agricultural landscapes. The analysis of in-hive stored pollen reflects the spectrum of visited plants and can be almost used to link the exposure to pesticides.In the current study, bee bread samples were collected in May and July from 17 sites located in southern Slovakia. Samples were analysed using a multi-residue pesticide analysis method for a broad spectrum of active substances and microscopic for pollen identification.Our results revealed a bee bread contamination with 19 different active substances, with fungicides being predominant. Sixteen of them are authorized in the EU, but chlorpyrifos, chlorpyrifos-methyl, and chloridazon are not. The highest concentrations for pendimethalin (1400 µg/kg), fluazifop-butyl (640 µg/kg), fenpropidin (520 µg/kg), fluopyram (130 µg/kg), and difenoconazole (95 µg/kg) were detected. The total residue load in bee bread sampled in the early season (May) was significantly higher than in the late season (July). The mean residue load of insecticides analysed in July comprised 46% of May’s load, which is alarming due to the importance of bee bread in the diet for winter-rearing bees. Moreover, results from both sampling periods showed that fungicides were positively associated with plant families Apiaceae and Papaveraceae and herbicides with Aceraceae, Salicaceae, and Brassica-type/Brassicaceae.Hence, bee bread can be considered a suitable matrix and a good bio-indicator reflecting honey bee exposure to pesticides over the season.

Contamination and pesticide multiresidue analysis in cotton production systems in Benin

High quantity of chemical pesticides spraying in conventional cotton production systems may affect negatively natural ecosystems components. This study examined the contamination levels of soil in Benin's cotton production system in West Africa by residues of pesticides used in cotton farming. One hundred and fourteen soil samples from six conventional and organic cotton production systems were collected and analysed. Multi-class pesticide residues were extracted from the soil samples, and analysed using respectively modified QuEChERS extraction and LC–MS/MS chromatography methods. Results showed an overall soil contamination to emamectin benzoate (18.5 μg/kg), imidacloprid (116.3 μg/kg), profenofos (12.7 μg/kg), acetamiprid (10.8 μg/kg), triasophos (12.6 μg/kg), abamectin (14.3 μg/kg), and deltamethrin (10.4 μg/kg). Especially, emamectin benzoate was detected with a high contamination in Banikoara district (18.5 μg/kg). Nevertheless, these contaminations were not deemed threatening from a toxicological perspective. Soils in conventional cotton cultivation displayed lower organic matter levels but higher concentrations of pesticides, whereas soils in organic cotton cultivation were less degraded and contaminated. Consequently, it is imperative to conduct environmental risk assessments and monitor key pesticide metabolites to establish sustainable cotton production systems in Benin.

Evaluation of pesticide residues in rice marketed in Cape Verde by QuEChERS-LC/GC-MS analysis

In this work, a multiresidue pesticide analysis using both gas chromatography and ultra-high performance liquid chromatography coupled to mass spectrometry systems has been conducted to determine 151 pesticides in rice samples consumed by the population of Cape Verde. The extraction and clean-up procedures were carried out by the QuEChERS method. The validation of both methodologies achieved determination coefficients higher than 0.9902 in matrix-matched calibration, relative recovery values in the range 58–120% with relative standard deviation lower than 20%, and limits of quantification of the method in the range 0.008–0.017 mg/kg, which agreed with the legal limits established by both EU regulations and the Codex Alimentarius guidelines. Among the total of 98 rice samples analysed, 91 samples were contaminated by pesticides at concentrations up to 18.3 mg/kg, with pirimiphos-methyl, propiconazole, tebuconazole, and imidacloprid being the most frequently detected. Following EU regulations, 14 non-compliances were found in 13 samples, whereas only one non-compliance was identified according to the Codex. Besides, a risk assessment based on the dietary exposure was performed for the pesticides found in the analysed rice samples. The results showed the need to carry out stricter controls to ensure the security of food agricultural products to protect consumers’ health.

Multiresidue Pesticide Analysis in Onion Using GC-MS/MS Using Modified QuEChERS Method with Zirconium Oxide Nanoparticle

Multiresidue Pesticide Analysis in Onion Using GC-MS/MS Using Modified QuEChERS Method with Zirconium Oxide Nanoparticle

Comparison of different fast gas chromatography - mass spectrometry techniques (Cold EI, MS/MS, and HRMS) for the analysis of pyrethroid insecticide residues in food.

In the multiclass, multiresidue analysis of pesticides in food and environmental samples, pyrethroid insecticides are generally more difficult to analyze than other types of analytes. They do not ionize well by electrospray ionization, and although they are suitable for analysis by gas chromatography-mass spectrometry (GC-MS), selectivity using standard electron ionization (EI) in GC-MS is often insufficient because the molecular ion is rarely present. Many pyrethroids tend to have the same fragment ions in MS or high-resolution (HR)MS, and similar ion transitions in tandem MS/MS, leading to difficulties in distinguishing different pyrethroids from each other and chemical interferences in complex matrices. In this study, different forms of fast GC coupled with different types of MS detectors were compared for the analysis of up to 15 pyrethroids in barley extracts as a test case to assess which approach was the most advantageous. The three studied GC-MS techniques consisted of Cold EI using supersonic molecular beams in selected ion monitoring (SIM) mode with a single quadrupole instrument; triple quadrupole MS/MS; and HRMS using an orbital ion trap (orbitrap). A higher flow rate was used in Cold EI, and low pressure (LP) GC was employed in the MS/MS and orbitrap methods, to speed up the GC analyses (<10 min chromatograms in all cases). Each technique had some advantages over the others depending on specific pyrethroid analytes in the matrix. Nontargeted LPGC-orbitrap typically yielded the highest selectivity, but it rarely achieved the needed detectability to quantidentify the residues at 10 ng g-1. Cold EI-SIM and LPGC-MS/MS usually met the needed detection limits and generally achieved similar capabilities for the targeted pyrethroids.

New sorbent-based hydrophobic alginic acid derivatives for fat removal in multi-pesticide residues: analysis of a fatty food sample.

Hydrophobic alginic acid derivatives were synthesized with various aliphatic hydrocarbon chains for fat removal in an analysis of multi-pesticide residues in a fatty food sample. First, alginic acid was chemically modified using eco-friendly ultrasound-assisted esterification with different alcohols, namely, hydrophobic alginic acid-methanol (HAA-C1), hydrophobic alginic acid-butanol (HAA-C4), and hydrophobic alginic acid-octadecanol (HAA-C18). The degree of esterification (DE) was determined by titration, and the results ranged from 57.3% to 63.7%. The physicochemical properties of the synthesized hydrophobic alginic acids (HAAs) were studied using FT-IR, XRD, TGA, and FE-SEM. Subsequently, the performance of the HAAs was checked and evaluated for the removal of fat from a fatty food sample by calculating the fat removal percentage and the determination of 214 pesticide residues in the fatty food sample. For the fat removal percentage application, the HAAs were able to efficiently remove between 77% and 83% of the fat; HAA-C18 had the highest percentage. Regarding the pesticide residue application, HAAs were also able to remove the fat content from the fatty food sample without a significant effect on the pesticide substances. The recoveries of the detected pesticide compounds were between 80% and 120% for all HAAs. However, there were various missing pesticide compounds for HAAs. The number of missing pesticide compounds was 19, 6, and 33 for HAA-C1, HAA-C4, and HAA-C18, respectively. HAA-C4 had medium hydrophobicity and it lost fewer pesticides than the other HAAs. This was because the multi-pesticide mixture had various classes of chemical structure; hence, it had different polarity powers. We concluded that HAAs are developable and applicable to be safely used as a green material in diverse fatty food sample analysis applications.

Beyond helium: hydrogen as a carrier gas in multiresidue pesticide analysis in fruits and vegetables by GC-MS/MS.

In this comprehensive study, we evaluated the feasibility of using hydrogen instead of helium as a carrier gas in a GC-MS/MS system for pesticide residue analysis, spanning three matrices: pepper, tomato, and zucchini. Initial assessments focused on the ion source's chemical inertness, employing nitrobenzene as a benchmark to monitor the hydrogenation process. A method with a duration of less than 12 minutes was developed, achieving good chromatographic peak resolution attributable to the enhanced chromatographic performance of hydrogen as a carrier gas. The study emphasized the optimization of system parameters, testing various ion source temperatures, detector voltages, and injection volumes. Sensitivity assessments, based on the DG-SANTE criteria, indicated that the majority of compounds were identifiable at a concentration of 5 μg kg-1 (81% in tomato, 84% in pepper and 73% in zucchini). Detailed validation for reproducibility, matrix effects, and linearity across 150 pesticides unveiled generally favorable outcomes, with a notable majority of compounds displaying low matrix effects, satisfactory linearity ranges and good reproducibility with most compounds returning a relative standard deviation (RSD) below 10%. When applied to 15 real samples, the hydrogen-based system's performance was juxtaposed against a helium-based counterpart, revealing that results are very comparable between both systems. This comparative approach highlights hydrogen's potential as a reliable and efficient carrier gas in pesticide residue analysis for routine food control laboratories, overcoming difficulties resulting from the lack of helium supplies.

(Multi-pesticides Residue Analysis in Cucumber under Greenhouse Conditions using QuEChERS methodology Coupled to GC-MS and HPLC)

(Multi-pesticides Residue Analysis in Cucumber under Greenhouse Conditions using QuEChERS methodology Coupled to GC-MS and HPLC)

Method optimisation for large scope pesticide multiresidue analysis in bee pollen: A pilot monitoring study

Pesticide contamination in emerging foods and supplements is currently a topic of great interest. This study focused on the evaluation of pesticide residues in commercial bee pollen samples to evaluate the risk associated with their consumption. To this end, an automated clean-up method for the pesticide extracts of bee pollen was developed. An LC-MS/MS and a GC-MS/MS method were validated for the analysis of 353 pesticides in 80 bee pollen samples purchased from different countries. The results showed the presence of 77 different pesticide residues in bee pollen, including plant protection chemicals and veterinary treatments. 85 % of the samples were contaminated with pesticides and no relevant differences were found between conventional and organic samples. Pesticide concentrations exceeding the imposed MRL were found in 40 % of the samples, but the risk assessment showed that consumers are not exposed to an unacceptable risk when consuming the evaluated bee pollen.

Pesticide residue analysis in different spice samples by automatic µSPE clean-up workflow determination using LC-MS/MS.

Spices such as paprika, curry, turmeric, dry chilli, and black pepper are grown in various geographic locations and widely used by consumers across the world. Pesticides applied during crop production practices could contaminate the produce, affecting the quality and posing ahealth risk for consumers. The complexity of thespice matrix and the wide range of target pesticides potentially present require special sample extraction and clean-up treatments to overcome matrix interference and ion suppression. In this study, sample extracts from spice matrices (paprika/curry/turmeric/dry chilli/black pepper) were cleaned up by anautomated µSPE clean-up method for multi-residue analysis of pesticides using LC-MS/MS. The automated µSPE clean-up method involves pre-filled cartridges containing varioussorbent materialssuitable for numerous co-extractives and the automated clean-up process was carried out using an autosampler. The regulatory limit for pesticides in spices varies with type, witha low MRL of 0.05 mg kg-1 or higher for 99% of the analytes. At spiking concentrations of 0.05 and 0.1 mg kg-1, good recoveries between 70 and 120% with RSD values below 20% were achieved for more than 98% of the compounds. With automatic clean-up of samples that takes 5 min/sample, 20% increased output per day shows animportant advantage achieved compared to manual clean-up.

Effect of resolution enhancement using metal ion assisted strategy based on electrospray ionization-ion mobility spectrometry: A case study of carbendazim and thiabendazole in fruits

A method for the rapid and simultaneous determination of carbendazim and thiabendazole residues by electrospray ionization-ion mobility spectrometry (ESI-IMS) combined with a metal ion-assisted technique was developed and validated in different fruit matrices. The metal ion assisted strategy was performed instead of tedious pre-separation procedures to overcome the limitation of low resolution of IMS. Four transition metal cations, Co(II), Ni(II), Cu(II), and Zn(II), were screened and their interactions with carbendazim and thiabendazole were investigated. The injection flow rate and metal ion concentration were optimized. The Cu(II) assisted approach helped to achieve well-separated peaks with a peak-to-peak resolution of 3.61. This method was then applied to detect carbendazim and thiabendazole simultaneously in apples, pears, bananas, and mangoes. The limit of detection (LOD) were 0.03 mg kg−1 and 0.13 mg kg−1 for carbendazim and thiabendazole, respectively, while spiked recoveries were 61.5–122.0% and 83.5–119.8%, respectively, with RSDs less than 13.9%. These satisfactory evaluation parameters indicated that the approach was capable of performing quantitative analysis of multi-pesticide residues. In addition, the feasibility of using metal ion assisted-ESI-IMS for the simultaneous detection also was theoretically demonstrated through molecular electrostatic potential analysis and binding energy calculation based on density functional theory (DFT). Both experimental and theoretical results revealed the effectiveness of the metal ion assisted strategy in improving the resolution of ESI-IMS.

Multi residue analysis of persistent organochlorine pesticides in fish from Baro River, Gambella, Southwest Ethiopia

In this study, the concentrations of organochlorine pesticides in thirty (30) randomly collected Tilapia Zilli fish samples from the Baro River, Ethiopia were determined. The pesticide residues were extracted by soxhlet extraction technique using a mixture of n-hexane and acetone. The extracts were cleaned with silica gel and analyzed using a GC-MS. Concentrations of organochlorine pesticides were calculated from linear calibration curves of nine mixtures of standards with a concentration range of 5-200 μg/kg in the fish sample and had correlation coefficients of 0.999 for all concentrations. The ranges of the limit of detections (LODs) and limit of quantifications ( LOQs) were 0.008–0.017 μg/kg and 0.025–0.052 μg/kg respectively. Recovery was determined from spiked samples at concentrations of 5 μg/kg, 60 μg/kg, and 200 μg/kg. Recoveries of 90.87–102.6% were obtained and the method precision calculated from relative standard deviation (RSD) was found to be 1.00–8.62%. Of the thirteen studied organochlorine pesticides five of them were detected in collected fish samples with concentrations of 67.08 μg/kg, 15.35 μg/kg, 16.6 μg/kg, 3.87 μg/kg, and 17.1 μg/kg for Endosulfan II, Endrin, Endosulfan I, 4,4’-DDD, and Chlordane, respectively. The occurrence of organochlorine pesticide residues in fish samples shows that these compounds have been used in the study areas. The levels of chlordane and Endosulfan II detected in fish samples were above the maximum residual limits (MRLs) set by the Codex Alimentarius Commission. Therefore public awareness of pesticide use and management needs to be worked on by concerned bodies.

Simultaneous analytical method for 296 pesticide multiresidues in root and rhizome based herbal medicines with GC-MS/MS

A method for the simultaneous analysis of pesticide multiresidues in three root/rhizome-based herbal medicines (Cnidium officinale, Rehmannia glutinosa, and Paeonia lactiflora) was developed with GC-MS/MS. To determine the concentrations of pesticide residues, 5 g of dried samples were saturated with distilled water, extracted with 10 mL of 0.1% formic acid in acetonitrile/ethyl acetate (7:3, v/v), and then partitioned using magnesium sulfate and sodium chloride. The organic layer was purified with Oasis PRiME HLB plus light, followed by a cleanup with dispersive solid-phase extraction containing alumina. The sample was then injected into GC-MS/MS (2 μL) using a pulsed injection mode at 15 psi and analyzed using multiple reaction monitoring (MRM) modes. The limit of quantitation for the 296 target pesticides was within 0.002–0.05 mg/kg. Among them, 77.7–88.5% showed recoveries between 70% and 120% with relative standard deviations (RSDs) ≤20% at fortified levels of 0.01, and 0.05 mg/kg. The analytical method was successfully applied to real herbal samples obtained from commercial markets, and 10 pesticides were quantitatively determined from these samples.