The presence of pesticide residues has become one of the main risk factors affecting the safety and quality of agro-food. In this study, a multi-residue method for the analysis of 284 pesticides in five local fruit cultivars in Shanghai was developed based on ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The limits of determination and the limits of quantitation of pesticides were 0.6–10 and 2–30 μg/kg, respectively. A total of 44, 10, 10, 18, and 7 pesticides were detected in strawberries, watermelons, melons, peaches, and grapes, respectively. The pesticide levels in 95.0% of the samples were below the maximum residual limits (MRLs) prescribed by China, and in 66.2% of the samples below the EU MRLs. The dietary risk assessment study showed big differences in the chronic and acute exposure risk values among different Chinese consumer groups. Through fruit consumption, children/females showed higher exposure risks than adults/males. But both the risk values were less than 100%, indicating that potential dietary risk induced by the pesticides was not significant for Chinese consumers. Nevertheless, certain measures are needed for both growers and the government in order to decrease the MRL-exceeding rate of pesticide residues and ensure the quality and safety of fruits for consumers.
A reliable and sensitive analytical method was developed for simultaneous determination of deoxynivalenol(DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), fusarenon X (FUS-X), and masked deoxynivalenol (deoxynivalenol-3-glucoside, D3G) in formula feed, concentrated feed, and premixed feed products. The method was based on an improved sample pretreatment with the commercially available HLB cartridges used for sample purification and enrichment followed by analysis using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Several key parameters including the extraction solvents, the positions of sample loading solvents, washing and elution solvents for HLB cartridges were carefully optimized to achieve optimal extraction and purification efficiencies. The established method was extensively validated by determining the linearity (R2 ≥ 0.99), sensitivity (limit of quantification in the range of 0.08–4.85 μg/kg), recovery (79.3%–108.1%), precision (Intra-day RSDs ≤ 13.5% and Inter-day RSDs ≤ 14.9%), and then was successfully applied to determine the four type B trichothecenes and D3G in a total of 31 feed samples. Among them, 26 were contaminated with various mycotoxins at the levels of 2.1–864.5 μg/kg, and D3G has also been detected in 17 samples with the concentrations in the range of 2.1–34.8 μg/kg, proving the established method to be a valuable tool for type B trichothecenes and masked DON monitoring in complex feed matrices.
1 July 2021 in Food Additives & Contaminants: Part B
A database of 392 pesticides established by an Ultrahigh performance liquid chromatography-tandem Q/Orbitrap high-resolution mass spectrometer (UPLC-Q/Orbitrap-HRMS) was used to screen multiple residues of pesticides in fruit and raw eaten vegetables from planting farms in Shanghai. Risk assessment was conducted with the screened results of the determined pesticides as to evaluate food safety. In 95% of the samples, one or more pesticides had a content below the maximum residue limits (MRLs) as set in the national Chinese standard. The co-occurrence of multi-residues of pesticides was more severe in peach and muskmelon, when compared with other food. All hazard index values of different groups were in the range of 0.19% to 12.3%, demonstrating that chronic dietary risk of studied fruits and raw eaten vegetables is low and the studied food samples were safe for human consumption in terms of these detected pesticides.
The Cuiguan pear is called “June snow” and the skin is thin; the meat is crisp and juicy; the taste is thick and fresh; and the juice is rich and sweet. In this study, the volatile organic compounds and the sensory and physicochemical parameters of the Cuiguan pear from four different regions of China (Sichuan (SC), Shangdong (SD), Chongming (CM), Zhuanghang (ZH)) were assessed. The highest differences in the physicochemical parameters were observed between four regions. The volatile fingerprints of GC-IMS showed great differences in the volatile of the Cuiguan pear, which suggested that the aroma of pears could be largely impacted by origin areas. (E)-ethyl-2-hexenoate can be used to distinguish between the ‘CM’ and pears from other regions. High contents of 2-heptanone, 1-pentanol, 1-butanol, 3-methylbutanol, butyl 2-methylbutanoate, heptyl acetate and butyl acetate were observed in the ‘SD’. Dimethyl trisulfide, 6-methyl-5-hepten-2-one, 3-hydroxy-2-butanone, 1-penten-3-one, beta-pinene, γ-terpinene, propanal, (e)-2-pentenal, (e)-2-heptenal, 1-pentanol and 3-methyl-1-pentanol were primarily contained in the ‘ZH’. Principal component analysis showed that there was very good discrimination based on the information obtained from GC-IMS for four samples. These findings were in agreement with the sensory analysis. In the opinion of the respondents to the consumer test, ‘ZH’ resulted in the most appreciated sample based on the average scores of the acceptability. This study provides some reference for the development and utilization of the Cuiguan pear.
In this study, a dispersive solid-phase extraction (DSPE) pretreatment procedure using zeolite H-Beta as a sorbent was exploited for the determination of eight neonicotinoids in bottled water and honey products based on ultra-high-performance liquid chromatography–tandem mass spectrometry analysis. The zeolite H-Beta was demonstrated to be a suitable sorbent for neonicotinoid insecticides, even after 10 recycles of reuse. The method performance was evaluated by the linearity (R2 ≥ 0.998), recovery (71–108%), precision (0.1–7.8%), limit of detection (0.05–0.1 ng/mL) and limit of quantification (0.1–0.2 ng/mL), which suggested excellent stability and high sensitivity with the use of the DSPE procedure. The method was further successfully applied in the test of neonicotinoid insecticides in 34 samples. Zeolite H-Beta shows promise as an efficient and practical material for monitoring neonicotinoid insecticides in bottled water and multiplex honey matrices.