Metabolite Residues Research Articles

Degradation Kinetics and Mechanism of β-Cypermethrin and 3-Phenoxybenzoic Acid by Lysinibacillus pakistanensis VF-2 in Soil Remediation.

Pyrethroid pesticide residues have detrimental effects on soil ecology and crop growth during insecticidal operations in agriculture. In this study, a novel strain Lysinibacillus pakistanensis VF-2 was isolated from long-term pesticide-treated cropland and had a maximum degradation efficiency of 81.66% for synthetic pyrethroid β-cypermethrin (β-CY) under optimized conditions. The analysis of intermediate products revealed that the degradation pathway of β-CY mainly involves ester bond hydrolysis, diphenyl ether decomposition, and phthalate ester degradation. Whole-genome sequencing and RT-qPCR analysis revealed the involvement of carboxylesterases, dioxygenases, and aromatic compound degrading enzymes in the degradation of β-CY. In the soil bioaugmentation experiment, the strain VF-2 can synergistically interact with indigenous microorganisms, significantly enhancing the degradation efficiency of β-CY and its metabolite 3-phenoxybenzoic acid (3-PBA) from 17.08% and 7.62% to 73.46% and 62.29%, respectively. This study suggests that strain VF-2 is a promising candidate for in situ coremediation of pyrethroid and intermediate metabolite residues in soil.

Rapid determination of caine-based anesthetics and their metabolite residues in fish using a modified QuEChERS method coupled with UPLC-MS/MS

Caine-based anesthetics are frequently used in the production and transportation of aquatic products, but residues in fish threaten human health. A rapid, sensitive, and effective method was developed for detecting caine-based anesthetics and their metabolite residues in fish using ultra-high performance liquid chromatography-tandem mass spectrometry coupled with a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. The sample was extracted with 0.05 % (v/v) formic acid-80 % acetonitrile, 4 g NaCl was added for liquid partitioning, and 50 mg C18 was used for purification. Matrix-matched calibrations showed good correlation coefficients with R2 ≥ 0.9942. The limits of detection were 0.5–4.4 ng/g. The recoveries ranged from 71.4 %–115.8 %, and the relative standard deviation for intra-day and inter-day precision was less than 8.5 % and 9.2 %, respectively. This method effectively analyzed the residues of caine-based anesthetics and their metabolites in fish and could be applied to aquatic product anesthetic regulation.

Highly sensitive time-resolved fluorescent microspheres lateral flow immunoassay for the quantitative detection of triadimefon and its metabolite residues in fruits and vegetables.

Ageneral one-step lateral flow immunochromatographic assay (LFIA) for the quantitative detection of triadimefon (TDF) and triadimenol(TDN) in fruit and vegetable samples was developedusing time-resolved fluorescence microspheres (TRFM) as labels. A specific anti-triadimefon monoclonal antibody (mAb) was conjugated with TRFM to fabricate LFIA test strips. A time-resolved fluorometer as an LFIA reader was applied to obtain quantitative results and assess risk ranges for the LFIA test strips. Under the optimized experimental conditions, the limits of detection (LODs) in buffer/cucumbers/tomatoes/oranges were 0.046ng/mL, 0.135µg/kg, 1.047µg/kg, and 5.811µg/kg, respectively, which are ca. 1000 times lower than that of colloidal gold-labeled strips. The recovery in cucumber/tomato/orange samples was 109.4-116.7%, 87.7-110.9%, and 88.0-111.9%, respectively, indicating that the test strips had good reliability. Coupled with the easily customizable pretreatment procedures for various samples, the LFIA results were obtained within 18min without the need for professional personnel or complicated equipment. TRFM-LFIA for TDF and TDN also shows remarkable specificity and precision. The test strips were also low-cost, portable, and convenientto use. These results indicate the test strips could be utilized as a novel strategy for on-site detection of TDF and TDN, which has the potential to expand and detect other pesticide or insecticide residues in food.

Magnetic covalent organic framework as an absorbent coupled with a portable mass spectrometer for rapid detection of malachite green and its metabolite residues

It is important to develop specific adsorbents for malachite green and other fish drug residues. Herein, a simple strategy for synthesizing a novel magnetic covalent organic frameworks (rFe3O4@Py-COF) has been studied, and the materials were used as a magnetic absorbent for solid phase extraction (MSPE) of malachite green (MG) and its metabolite as leucomalachite green (LMG) in fishes. In this study, the mild reduction program of formic acid replacing traditional sodium borohydride as a reducing agent has been adopted to increase the stability of the framework, which can maintain the original high crystallinity and surface area of the reduced COF. The secondary amine bond is expected to be used as the reaction center for further functionalization of COF pore wall. Subsequently, rFe3O4@Py-COF (rmCOF) obtained after reduction was used as MSPE materials to detect MG and LMG by a portable mass spectrometer. After optimizing the conditions, the linearity is good within the range of 1.25∼100 μg/kg (R2≥0.9954), the limits of detection (LODs) are 0.31∼0.44 μg/kg with satisfactory recovery (85.0 %∼106.0 %). These results indicate that the assay is suitable for monitoring MG and LMG in complex aquatic foods, providing protection for food safety.

Preparation of monoclonal antibodies recognizing pharmacologically active metabolites of metamizole based on rational hapten design and their application in the detection of animal-derived food

Metamizole (MET) is an antipyretic and analgesic drug, the illegal use of which can result in residues of MET metabolites in edible tissues of animals. In this study, a computational chemistry-assisted hapten screening strategy was used to screen for the optimal immunogenic hapten-A and the optimal coating antigen hapten-G-OVA. A monoclonal antibody capable of recognizing two pharmacologically active metabolites of MET, 4-methylamidinoantipyrine (MAA) and 4-aminoantipyrine (AA), was prepared from the hapten-A. The antibody showed excellent specificity for MAA and AA and almost no cross-reactivity with the pharmacologically inactive metabolites 4-formamidinoantipyrine (FAA) and 4-acetamidinoantipyrine (AAA). An ic-ELISA was developed for the simultaneous detection of MAA and AA in animal-derived food, the limits of detection for MAA ranged from 0.93 to 1.18 μg/kg, while those for AA ranged from 1.74 to 4.61 μg/kg. The recovery rate fell within the range of 82 %–110 %, with a coefficient of variation less than 16.39 %.

Sensitivity Variations in Developmental Toxicity of Imidacloprid to Zebrafish Embryos at Different Neurodevelopmental Stages.

Neonicotinoids are ubiquitous in global surface waters and pose a significant risk to aquatic organisms. However, information is lacking on the variations in sensitivity of organisms at different developmental stages to the neurotoxic neonicotinoids. We established a spectrum of toxicity to zebrafish embryos at four neurodevelopmental stages (1, 3, 6, and 8 h post fertilization [hpf]) and dechorionated embryos at 6 hpf based on external and internal exposure to imidacloprid as a representative neonicotinoid. Embryos at the gastrula stage (6 and 8 hpf) were more sensitive to imidacloprid than embryos at earlier developmental stages. Dechorionated embryos were more sensitive to imidacloprid than embryos with a chorion, suggesting that the chorion offers protection against pollutants. Nine sublethal effects were induced by imidacloprid exposure, among which uninflated swim bladder (USB) was the most sensitive. Water depth and air availability in the exposure chambers were critical factors influencing the occurrence of USB in zebrafish larvae. Internal residues of metabolites accounted for <10% of imidacloprid, indicating that imidacloprid was metabolized in a limited fashion in the embryos. In addition, acute toxicity of the main metabolite 5-hydroxy-imidacloprid was significantly lower than that of imidacloprid, indicating that the observed toxicity in embryos exposed to imidacloprid was mainly induced by the parent compound. Our research offers a fresh perspective on choosing the initial exposure time in zebrafish embryo toxicity tests, particularly for neurotoxicants. Environ Toxicol Chem 2024;43:2398-2408. © 2024 SETAC.

Simultaneous determination of phenothiazine drugs and their metabolites residues in animal derived foods by high performance liquid chromatography tandem mass spectrometry

Due to their potential entry into the human body via the food chain, phenothiazine drugs and their metabolites pose specific health hazards, making their detection in edible tissues of paramount importance. In this research endeavor, a highly sensitive multi-residue analytical method has been devised for the detection of phenothiazine drugs and their metabolites in animal-derived food products, utilizing high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The preparation of samples involved the use of 1% formic acid in acetonitrile as the extraction solvent following sample weighing, with multiple extraction steps diligently performed to ensure optimal outcomes. The sample, post-extraction, was directly introduced into the purification column, yielding significant time savings and rendering the process more environmentally sustainable. This procedural step effectively eliminated interfering substances from the sample matrix, including proteins, salts, and phospholipids. Analysis of the extracted samples was conducted through HPLC-MS/MS, employing an electrospray ionization (ESI) ion source. A comprehensive panel of 20 phenothiazine drugs and their metabolites was successfully resolved within a mere 10-min chromatographic run. A robust linear correlation (R2 ≥ 0.99) was attained within a judiciously chosen range of concentrations. Method validation was meticulously conducted across multiple animal species, including trout, white shrimp, pork, beef and chicken. The developed analytical method has been effectively deployed for the screening and quantification of phenothiazine drugs in real-world samples sourced from commercial livestock and aquatic products.

Unveiling the Contamination Patterns of Neonicotinoid Insecticides: Detection, Distribution, and Risk Assessment in Panax notoginseng across Plant Parts.

This study analyzed neonicotinoid insecticides (NEOs) and metabolite (m-NEOs) residues in 136 Panax notoginseng samples via ultra-performance liquid chromatography-tandem mass spectrometry. Imidacloprid was the most detected NEO (88.24% of samples), ranging from 1.50 to 2850 μg/kg. To the best of our knowledge, some novel NEOs were detected in P. notoginseng for the first time. NEO clustering patterns varied among plant parts, with higher contamination in leaves and flowers. Fourteen NEO/m-NEOs, including cycloxaprid and acetamiprid, showed site-specific behavior, indicating the possibility of using multiple NEOs simultaneously during planting, resulting in formation of distinct metabolites in different plant parts. Transfer rates in decoction and infusion ranged from 10.06 to 32.33%, reducing residues postprocessing. Dietary risk assessment showed low hazard quotients (HQa: 7.05 × 10-7 to 2.09 × 10-2; HQc: 3.74 × 10-7 to 2.38 × 10-3), but risk-ranking scores indicated potential hazards with imidacloprid and acetamiprid in flowers and leaves. The findings are expected to promote safety assessment and distribution research of NEOs in plants.

Determining nine fasciolicides and three metabolite residues in milk and infant formula using solid-phase extraction and liquid chromatography–tandem mass spectrometry

A new sensitive method of liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis for nine fasciolicides (closantel, rafoxanide, oxyclozanide, niclosamide, nitroxinil, ioxynil, 4-nitro-3-(trifluoromethyl)phenol, salicylanilide, and triclabendazole) and three metabolite residues (ketotriclabnedazole, triclabendazole sulfone, and triclabendazole sulfoxide) in milk and infant formula was established. The samples were extracted and purified through solid-phase extraction and analyzed using LC–MS/MS. The proposed method demonstrated high accuracy (the average recoveries ranged from 70.5 % to 107.4 %) and high sensitivity (the limits of quantification ranged from 1.0 to 25.0 µg/kg). This method was successfully applied to determine nine fasciolicides and three metabolite residues in 45 milk and infant formula, providing technical support for the safety and quality evaluation of dairy products.

Soil and unsaturated zone as a long-term source for pesticide metabolites in groundwater

Pesticide metabolites are frequently detected in groundwater, often exceeding the concentrations of their parent pesticides. Ceasing the application of certain pesticides has often not led to the expected decrease in metabolite concentrations in groundwater, which is potentially caused by residues in soil. Whereas pesticide residues in soils are well-documented, there are only few studies about metabolite residues. We investigated if the soil/unsaturated zone can act as a long-term source for metabolites in groundwater by combining soil analysis, groundwater analysis and numerical modelling. The field study focused on the herbicide chloridazon (CLZ) and its frequently detected metabolites desphenyl-chloridazon (DPC) and methyl-desphenyl-chloridazon (MDPC) while in the model additional pesticides and metabolites were considered. In soil samples from an agricultural area, where the last CLZ application was 5 to 10 years ago, we observed 10 times (DPC: 0.22 – 7.4 µg kg−1) and 6 times (MDPC: 0.12 – 3.1 µg kg−1) higher metabolite concentrations compared to CLZ (< 0.050 – 1.0 µg kg−1). Calculations suggested that the majority of the metabolites (DPC: 63 - 96%, MDPC: 74 – 97%) were sorbed despite their lower sorption tendency. The metabolite retention was in particular related to the organic carbon content. The calculated pore water concentrations were highest in the deepest part of the soil profile (75 – 100 cm) with median concentrations of 3.6 and 1.7 µg L−1 for DPC and MDPC, respectively. The groundwater concentrations of DPC and MDPC were 3 to 3.5 times higher in monitoring wells downgradient from the agricultural zone than upgradient of it. This increase highlights the potential of soil and unsaturated zone as a long-term metabolite source after the application stop of pesticides, consistent with the calculated elevated pore water concentrations. Numerical flow and transport model simulations suggested that this input from soil and unsaturated zone can cause elevated metabolite concentrations (> 0.1 µg L−1) in groundwater over more than one decade. The study highlights that soil and unsaturated zone can act as a long-term source of pesticide metabolites even if they have much higher mobility than the parent compound.

Method validation and residue analysis of fluoxapiprolin and its metabolites on tomato by QuEChERS method combination with liquid chromatography tandem mass spectrometry (LC-MS/MS)

ABSTRACT Field experiments were conducted to investigate the dissipation and persistence of fluoxapiprolin and its metabolites (BDM-pyrazole, Pyrazole-acetic acid, Pyrazole-methyl sulphinyl acid, Pyrazole-alanine and Pyrazole-alanine oxopropanoic acid). For method validation, all the samples were spiked with fluoxapiprolin and its metabolites at different levels. The mean recoveries of fluoxapiprolin and its metabolites were more than 75%. For field application, the treatments consisted of one control and two different doses of Fluoxapiprolin 20 g L−1 as suspension concentrate (25 and 50 g ha−1). Tomato fruit samples were collected at random in each replication separately at 0, 1st, 3rd, 5th, 7th, 14th, 21st and 28th days after third application. Soil sample was collected at random in each plot separately at 21 days after the third application. Initial residues of fluoxapiprolin were found to be 0.08 and 0.11 mg kg−1 at 25 and 50 g a.i.ha−1. Residues of fluoxapiprolin were observed up to 7 days of spray. No metabolites of fluoxapiprolin were found in tomato samples. Soil samples collected on the 21st day after the third application did not reveal the presence of fluoxapiprolin and its metabolites residues at both the doses.

A rapid solid-phase extraction purification combined with UPLC[sbnd]MS/MS used for simultaneous determination of eight tetracyclines and three metabolite in chicken and pork

A method for rapid detection and identification of 8 tetracyclines (TCs) and 3 metabolite residues in chicken and pork was established and verified by combining rapid solid-phase extraction (SPE) technology with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLCMS/MS). After a sample was extracted, it was purified with a PRiME HLB cartridge, and the cartridge did not need to be activated, balanced, or eluted. The filtrate was dried under nitrogen, redissolved, and subsequently analyzed via UPLCMS/MS. The limits of detection for chicken and pork were 0.05–0.48 μg/kg and 0.05–0.52 μg/kg, respectively. The limits of quantification were 0.16–1.61 μg/kg and 0.16–1.75 μg/kg, respectively. The recoveries were 85.15%–107.50% and 84.21%–106.37%, respectively. The established method was suitable for qualitative and quantitative analyses of TCs and their metabolite residues in chicken and pork and has been used for the detection of TC in chicken and pork samples from local markets.

Residual estimation of spirotetramat and its metabolites in chilli and soil by LC-MS/MS.

Two applications of spirotetramat were done to study the dissipation and persistence of spirotetramat and its four different metabolites in chilli and soil at 10days interval. Total spirotetramat residues were estimated by LC-MS/MS instrument. The mean initial deposits of total spirotetramat after application of spirotetramat 15.31 OD @ 60 (X dose), 75 (1.25 × dose) and 120 (2 × dose) g a.i. ha-1 on green chilli were found to vary from 0.38 to 0.83mgkg-1 during the initial year. Spirotetramat and its metabolite residues in green chilli were found to be below limit of quantification (0.01mgkg-1) after 15days of application. The spirotetramat cis enol (the major metabolite) was formed in both the soil and the plant. The residues of spirotetramat-monohydroxy were below LOQ irrespective of any substrate during the estimation. In soil, the total initial spirotetramat deposits for the 1st year were found 0.09 for X dose, 0.12 for 1.25 × dose and 0.20mgkg-1 for 2 × dose. After 3days for both X and 1.25 × doses and 5days for 2 × dose, the total spirotetramat residues were below LOQ. The spirotetramat's half-life values have been determined to be between 3.19 and 3.93days and 1.00 and 1.59days, respectively, in soil and green chilli fruits. One day waiting period is proposed for the safe consumption of green chilli when the spirotetramat was applied irrespective of the dose.

Dissipation, residues, and evaluation of processing factor for spirotetramat and its formed metabolites during kiwifruit growing, storing, and processing.

Spirotetramat is widely used around the world to control sucking pests and may form in agricultural products. In the current study, the dissipation, residues, and evaluation of processing factor (PF) for spirotetramat and its formed metabolites were investigated during kiwifruit growing, storing, and processing. The residue analysis method was established based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) combined with a QuEChERS method to detect the residues of spirotetramat and its metabolites in kiwifruit and its processed products. The method provided recoveries of 74.7-108.7%, and the relative standard deviations (RSDs) were 0.6-13.1%. The LOQs of spirotetramat and its four metabolites were 1 μg kg-1. The degradation of spirotetramat was best fitted for the first-order kinetics model with a half-life of 9.90-10.34 days in the field and 24.75-30.13 days during storage. Residues of spirotetramat and its formed metabolites in kiwifruit would not pose dietary risk to consumers. Moreover, the peeling and fermentation were the highest removal efficiency for the spirotetramat and its formed metabolite residues during processing. The PF values calculated after each individual process were < 1, indicating a significant reduction of residues in different processing processes of kiwifruit. The spirotetramat was degraded during kiwifruit wine-making process with half-lives of 3.36-4.91 days. B-enol and B-keto were the main metabolites detected in kiwifruit and its processed products. This study revealed the residues of spirotetramat and its formed metabolites in kiwifruit growing, storing, and processing, which helps provide reasonable data for studying the dietary risk factors of kiwifruits and products.

An innovative nanoparticle-modified carbon paste sensor for ultrasensitive detection of lignocaine and its extremely carcinogenic metabolite residues in bovine food samples: Application of NEMI, ESA, AGREE, ComplexGAPI, and RGB12 algorithms.

Nowadays, veterinary medicine residues have been viewed as a major threat to food safety worldwide, especially when dealing with carcinogenic residues. Herein, we present the first differential pulse voltammetric method for the quantification of lignocaine and its carcinogenic metabolite 2,6-xylidine residues in bovine food samples, aided by five greenness and whiteness assessment tools, including NEMI, ESA, ComplexGAPI, AGREE, and RGB12. The method depends on the electrochemical oxidation after modification of the carbon paste sensor with recycled Al2O3-NPs functionalized multi-walled carbon nanoparticles. The produced sensor (Al2O3-NPs/MWCNTs/CPE) was characterized using XRD, FT-IR, EDX, SEM, and TEM. As expected, the active surface area and electron transfer processes were accelerated by the modification, resulting in ultra-sensitive quantification with detection limits of 19.00 and 13.94nM for lignocaine and 2,6-xylidine, respectively. In terms of greenness, whiteness, sustainability, analytical effectiveness, and economic and practical considerations, the proposed method outperforms the reported methods.

Original-structure-based hapten design strategy and development of a derivatization-free gold-based paper lateral-flow immunoassays for detecting furaltadone metabolite in shrimp

Veterinary drug residues in food-producing animals pose a threat to human health and public safety, and accurate measurement of these drug residues is necessary. However, detecting nitrofuran metabolite residues is challenging because of their low molecular weight and the long derivatisation time required for their indirect detection. Current antibodies produced against these metabolites have limited accuracy and sensitivity owing to the traditional and ineffective hapten design based on the reaction of 3-amino-5-morpholinomethyl-2-oxazolidone (AMOZ) with nitrobenzaldehyde. In this study, a new antigen strategy was adopted using an original-structure-based hapten design combined with a new carrier protein with immunosynergistic effects to produce a monoclonal antibody that could recognise the metabolite of furaltadone (AMOZ) directly without derivatisation with excellent analytical performance. Finally, a gold-based paper lateral flow immunoassay for AMOZ without derivatisation was established with a visual limit of detection of 5 ng/mL, IC50 of 0.97 ng/mL and linear range (IC20∼IC80) of 0.45–2.07 ng/mL. The method was sensitive and accurate, and detection was completed within 10 min. This new antigen design strategy provides a theoretical basis and reference for antibody production of other ultrasmall molecules.

Modification of the existing maximum residue levels for metazachlor in leeks and honey.

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted a request to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for the active substance metazachlor in leeks and honey. The data submitted in support of the request were found to be sufficient to derive MRL proposals. Adequate analytical methods for enforcement are available to control the residues of metazachlor metabolites 479 M04, 479 M08 and 479 M16 in plant matrices and honey at the validated limit of quantification (LOQ) of 0.01 and 0.02 mg/kg for each analyte. Based on the risk assessment results, EFSA concluded that the short-term and long-term intake of residues resulting from the use of metazachlor according to the reported agricultural practice is unlikely to present a risk to consumer health.

Simultaneous Determination of Neonicotinoid Insecticides and Metabolites Residues in Milk and Infant Formula Milk Powder by EMR-Liquid Chromatography-Tandem Mass Spectrometry

Simultaneous Determination of Neonicotinoid Insecticides and Metabolites Residues in Milk and Infant Formula Milk Powder by EMR-Liquid Chromatography-Tandem Mass Spectrometry

Highly-Selective Analytical Strategy for 90 Pesticides and Metabolites Residues in Fish and Shrimp Samples.

The analysis of pesticide residues in aquatic products is challenging due to low residue levels and the complex matrix interference. In this study, we developed a simple, fast method for the trace analysis of 90 pesticides and metabolites in aquatic products. The analytes covered a wide polarity range with log Kow (log octanol-water partition coefficient) ranging from -1.2 to 6.37. Grass carp (Ctenopharyngodon idellus) and prawn (Penaeus chinensis) samples were chosen to validate the quantification method. The samples were extracted by 0.2% formic-acetonitrile, cleaned by solid-phase extraction (PRiME HLB), and analyzed by high performance liquid chromatography-tandem mass spectrometry. The results showed good linearities for the analytes and were observed in the range of 0.05-50 μg/L. The recoveries of the method were within 50.4-118.6%, with the relative standard deviations being lower than 20%. The limits of quantifications (LOQs) of the method were in the range of 0.05-5.0 μg/kg, which were superior to values compared with other research. The developed method was applied to detect pesticide residues in prawn samples from eastern coastal areas of China. Three herbicide residues of diuron, prometryn, and atrazine were detected in prawn samples. The method was sensitive and efficient, which is of significance in expanding the screening scope and improving the quantitative analysis efficiency in aquatic products.

Surveillance of Nitrofuran Metabolite Residue in Pacific White Shrimp (Litopenaeus vannamei) at Local Market in Bangkok

The study aimed to analyze nitrofuran metabolite residues in Pacific white shrimp (Litopenaeus vannamei) from the 5 local markets in Bangkok. The samples weighing from 9.20+0.79 to 31.00+0.67 g were analyzed for nitrofuran metabolites: 3-amino-2-oxazolidinone (AOZ), 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ), 1-aminohydantoin (AHD) and semicarbazide (SEM) by using LC-MS/MS technique. The results showed that only SEM in the range 0.104-0.160 ug/kg was found. The correlation coefficient between weight and SEM showed the negative linearity (r = -0.6867). It was found that there were less SEM residues in large shrimps than small shrimps. Therefore, the size of white shrimp can be used as an index for purchasing shrimp that are safe for consumers.