Risk assessment of multiple pesticide residues in Agrocybe aegerita: Based on a 3-year monitoring survey.

The presence of pesticide residues in Agrocybe aegerita has raised an extensive concern. In this paper, based on a 3-year monitoring survey, the dietary exposure risks through A. aegerita consumption for different population subgroups were assessed using both deterministic and semi-probabilistic approaches under the best-case and the worst-case scenarios. Among the 52 targeted pesticides, 28 different compounds were identified in the concentration range of 0.005-3.610 mg/kg, and 87.4 % of samples contained one or more pesticide residues. The most frequently detected pesticide was chlormequat, followed by chlorfenapyr and cyhalothrin. The overall risk assessment results indicated extremely low chronic, acute, and cumulative dietary exposure risks for consumers. Using the ranking matrix, intake risks of pesticides were ranked, revealing endsoluran, chlorpyrifos, and methamidophos to be in the high-risk group. Finally, considering various factors such as the toxicity and risk assessment outcomes of each positive pesticide, use suggestions were proposed for A. aegerita cultivation.

Residue Behaviors and Degradation Dynamics of Insecticides Commonly Applied to Agrocybe aegerita Mushrooms from Field to Product Processing and Corresponding Risk Assessments.

Residual pesticides in Agrocybe aegerita mushroom have emerged as a significant concern and bring much uncertainty due to processing procedures. In this study, a modified QuEChERS sample preparation procedure and UPLC-MS/MS were used to analyze the residual levels of four commonly used pesticides in A. aegerita from field to product processing. The field results showed that dissipation of these targeted chemicals was consistent with the first-order kinetics, and the half-life time ranged from 20.4 h to 47.6 h. The terminal residues of the four pesticides at harvest time ranged from 9.81 to 4412.56 µg/kg in raw mushroom. The processing factors (PFs) of clothianidin, diflubenzuron, chlorbenzuron, and pyridaben ranged from 0.119 to 0.808 for the drying process and from 0.191 to 1 for the washing process. By integrating the data from the field trials, the PFs, and the consumption survey, the chronic dietary risks of the target chemicals via A. aegerita intake ranged from 2.41 × 10-5 to 5.69 × 10-2 for children and from 6.34 × 10-6 to 1.88 × 10-2 for adults, which are considerably below the threshold of 1, indicating no unacceptable risk to consumers in the Fujian province of China. This research offers foundational data for appropriate use and the maximum residue limit (MRL) establishment for these four insecticides in A. aegerita.

Simultaneous determination of six glycosidic aroma precursors in pomelo by ultra-high performance liquid chromatography-tandem mass spectrometry.

An ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established and validated for the simultaneous determination of six glycosidic aroma precursors in pomelo, including geraniol ß-glucoside, geraniol ß-primeveroside, linalool ß-primeveroside, benzyl ß-primeveroside, 2-phenylethyl ß-primeveroside and nerolidol ß-primeveroside. The results showed that the proposed method has the advantages of rapidity, high sensitivity, and good accuracy. Six glycosidic aroma precursors were effectively separated in a short run time (13 min), and the limit of detection, limit of quantification, recovery, and repeatability of analytes were 0.321-4.47 ng mL-1, 1.07-14.9 ng mL-1, 94.4-109.1%, and 5.2-14.5%, respectively. The developed method was applied to analyze the contents of glycosidic aroma precursors in different organs of pomelo plant, including leaves, flowers and fruits. The analytical result showed that glycosidic aroma precursor contents in plant leaves, flowers and fruits were in the range of 0-5964.9 µg kg-1, and more glycosidic aroma precursors were found in flowers than in leaves or fruits. It is envisioned that the proposed UPLC-MS/MS method have promising application in qualifying and quantifying these six glycosidic aroma precursors in pomelo.

[Simultaneous determination of four fluoroquinolone residues in fish by ion-pair high performance liquid chromatography].

An ion-pair high performance liquid chromatographic method with a fluorescence detector was established to determine four fluoroquinolone residues in fish. The chromatographic conditions were as follows: Waters microBondapak C18 column (3.9 mm i.d. x 300 mm, 10 microm) was used at 40 degres C with 11 mmol/L tetrabutylammonium bromide solution (pH 3.0) acetonitrile (94: 6, v/v) as the mobile phase with a flow rate of 1.0 mL/min, at the excitation wavelength of 280 nm and emission wavelength of 460 nm. The detection limit for fish was 1 microg/kg. The linear range was from 6-100 microg/kg, and correlation coefficients were more than 0.9995. At the levels of 10, 50 and 100 microg/kg, the recoveries were 76%-100% with relative standard deviations of less than 7%. The method developed can meet the requirement for residue analysis.