Determination of 43 pesticide residues in intact grape berries (Vitis Vinifera L.) by using an ultrasound-assisted acetonitrile extraction method followed by LC–MS/MS

Decline pattern and dietary risk assessment of spinetoram in grapes under Egyptian field conditions

Spinetoram is one of the most extensively used insecticides globally and is a new spinosyn-based insecticide registered for direct treatment of Egyptian grapes. This work established and validated a developed method for determining spinetoram in grape berries and leaves using the QuEChERS coupled LC-MS/MS technique. The average recoveries ranged between 98.52-101.19% and 100.53-104.93%, with RSDs of 2.74-6.21% and 2.79-7.26% for grape berries and leaves, respectively. Spinetoram residues degraded in grape berries and leaves through a first-order kinetic, with an estimated half-life (t1/2) of 4.3 and 2.8 days in grape berries and leaves, respectively, and significant degradation (91.4-97.5%, respectively) after 14 days. Besides, the terminal residues of spinetoram detected in grape berries and leaves samples ranged between 0.017-0.077 mg‧kg-1 and 0.79-0.023 mg·kg-1, respectively, when applied two to three times at a single recommended rate, while it was varied between 0.026-0.44mg‧kg-1 and 0.79-0.023mg‧kg-1 when applied two to three times at a double recommended rate, respectively. A dietary risk assessment was conducted using scientific data from field trials, acceptable daily intake (ADI), and food consumption. It was determined that no noteworthy health hazards were connected to eating grape berries and leaves that had been treated with spinetoram since the risk quotients (RQs) were ≤ 0.4.

Occurrence, distribution, and translocation of legacy and current-use pesticides in pomelo orchards in South China

Pomelo (Citrus grandis) is a highly popular and juicy member of the citrus family. However, little is known regarding the occurrence and distribution of pesticides in pomelo. In this study, we determined the levels of legacy (n = 25) and current-use pesticides (n = 2) in all parts of pomelo (i.e., epicarp, mesocarp, endocarp, pulp, and seed) and paired soil and leaf samples collected from two pomelo orchards in South China. At least one target pesticide was detected in the pomelo fruit, soil, and leaf samples, indicating that these pesticides were ubiquitous. The spatial distribution of the total concentration of pesticides in the pomelo parts was in the order of epicarp (216 ng/g) > mesocarp (9.50 ng/g) > endocarp (4.40 ng/g) > seed (3.80 ng/g) > pulp (1.10 ng/g), revealing different spatial distributions in pomelo. Principal component analysis was performed based on the concentrations of the target pesticides in the pulp and paired samples of epicarp, leaf, topsoil, and deep soil to examine the translocation pathway of the pesticides in pomelo. Close correlations were found among the target pesticides, and the pesticides in the pulp were mainly transferred from the epicarp, topsoil, or deep soil. We also explored the factors that affected such transport and found that the main translocation pathway of the non-systemic pesticide (i.e., buprofezin) into the pulp was the epicarp, whereas the systemic pesticide (i.e., pyriproxyfen) was mainly derived from the soil. The cumulative chronic dietary risks of all the pesticides resulting from pomelo consumption were much lower than the acceptable daily intake values for the general population. However, the prolonged risk of exposure to these pesticides should not be underestimated. The potential health risks posed by legacy and current-use pesticides, which are widely and frequently utilized, should be given increased attention.

Recent Advances in Fluorescent Nanoprobes for Food Safety Detection

Fluorescent nanoprobes show similar fluorescence properties to traditional organic dyes, but the addition of nanotechnology accurately controls the size, shape, chemical composition, and surface chemistry of the nanoprobes with unique characteristics and properties, such as bright luminescence, high photostability, and strong biocompatibility. For example, modifying aptamers or antibodies on a fluorescent nanoprobe provides high selectivity and specificity for different objects to be tested. Fluorescence intensity, life, and other parameters of targets can be changed by different sensing mechanisms based on the unique structural and optical characteristics of fluorescent nanoprobes. What's more, the detection of fluorescent nanoprobes is cost-saving, simple, and offers great advantages in rapid food detection. Sensing mechanisms of fluorescent nanoprobes were introduced in this paper, focusing on the application progress in pesticide residues, veterinary drug residues, heavy metals, microbes, mycotoxins, and other substances in food safety detection in recent years. A brief outlook for future development was provided as well.

Centrifugation-Assisted Solid-Phase Extraction Coupled with UPLC-MS/MS for the Determination of Mycotoxins in ARECAE Semen and Its Processed Products

Mycotoxins can occur naturally in a variety of agriculture products, including cereals, feeds, and Chinese herbal medicines (TCMs), via pre- and post-harvest contamination and are regulated worldwide. However, risk mitigation by monitoring for multiple mycotoxins remains a challenge using existing methods due to their complex matrices. A multi-toxin method for 22 mycotoxins (aflatoxin B₁, B₂, G₁, G₂, M₁, M₂; ochratoxin A, B, C; Fumonisin B₁, B₂, B₃; 15-acetyldeoxynivalenol, 3-acetyldeoxynivalenol, diace-toxyscirpenol, HT-2, T-2, deepoxy-deoxynivalenol, deoxynivalenol, neosolaniol, zearalenone, and sterigmatocystin) using centrifugation-assisted solid-phase extraction (SPE) clean-up prior to ultra-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis for Arecae Semen and its processed products was developed and validated. Several experimental parameters affecting the extraction and clean-up efficiency were systematically optimized. The results indicated good linearity in the range of 0.1-1000 μg/kg (r² > 0.99), low limits of detection (ranging from 0.04 μg/kg to 1.5 μg/kg), acceptable precisions, and satisfactory recoveries for the selected mycotoxins. The validated method was then applied to investigate mycotoxin contamination levels in Areca catechu and its processed products. The mycotoxins frequently contaminating Areca catechu were aflatoxins (AFs), and the average contamination level and number of co-occurring mycotoxins in the Arecae Semen slices (Binlangpian) were higher than those in commercially whole Arecae Semen and Arecae Semen Tostum (Jiaobinlang). Sterigmatocystin was detected in 5 out of 30 Arecae Semen slices. None of the investigated mycotoxins were detected in Arecae pericarpium (Dafupi). The results demonstrated that centrifugation-assisted SPE coupled with UHPLC-MS/MS can be a useful tool for the analysis of multiple mycotoxins in Areca catechu and its processed products.