Dissipation kinetics, pre-harvest residue limits, and hazard quotient assessments of pesticides flubendiamide and fluopicolide in Korean melon (Cucumis melo L. var. makuwa) grown under regulated conditions in plastic greenhouses

Abstract

The dissipation kinetics, pre-harvest residue limits, and hazard quotient (HQ) assessments of the pesticides flubendiamide and fluopicolide were conducted for Korean melon (Cucumis melo L. var. makuwa) cultivated at two different sites. A single extraction and cleanup procedure was carried out using acetone (partitioned with dichloromethane) and amino solid-phase extraction cartridges, respectively. Residue analysis was performed by HPLC with ultraviolet detection. Both pesticides showed excellent linearity with correlation coefficients of 0.9999 and 0.9996 for flubendiamide and fluopicolide, respectively. The accuracy (expressed as recovery %) at three spiking levels was 92.0-103.6 and 82.8-105.3%, and the precision (expressed as relative standard deviation) was 1.7-3.4 and 2.7-5.3% for flubendiamide and fluopicolide, respectively. The initial residues of flubendiamide/fluopicolide were 0.326/0.376 and 0.206/0.298 mg/kg at sites 1 and 2, respectively. These amounts were substantially lower than the maximum residue limits (MRLs = 1 and 0.5 mg/kg for flubendiamide and fluopicolide, respectively) established by the Korean Ministry of Food and Drug Safety. The half-lives of flubendiamide were 5.8 and 6.5 days, and those of fluopicolide were 6.7 and 9.1 days at sites 1 and 2, respectively. The shorter half-lives were attributed to seasonal variations (higher temperatures) and enzymatic and metabolic profiling. The risk assessment HQs of flubendiamide were 0.217/0.249 on day 0, which decreased to 0.102/0.168 on day 5, and to 0.065/0.88 on day 10; the HQ values for fluopicolide were 0.029/0.042, 0.022/0.025, and 0.010/0.019 on day 0, day 5, and day 10, for sites 1/2, respectively. From this data, we concluded that the fruits could be consumed safely.

Dissipation Behavior and Dietary Risk Assessment of Thiamethoxam, Pyraclostrobin, and Their Metabolites in Home-Style Pickled Cowpea

“…where C sum denotes the overall residue concentration of PYR; C PYR and C BF 500-3 are the concentrations of PYR and BF 500-3, respectively; M PYR and M BF 500-3 are the molecular weights of PYR (387.82) and BF 500-3 (357.80), respectively. The potential human health risks associated with long-term consumption of pickled cowpea and the intake of THI and PYR were determined using applicable Equations ( 5) and ( 6) [29][30][31]:…”

“…The potential human health risks associated with long-term consumption of pickled cowpea and the intake of THI and PYR were determined using applicable Equations (5) and (6) [ 29 , 30 , 31 ]: where RQ d is the dietary risk quotients, EDI is the estimated daily intake (mg), and ADI is the acceptable daily intake (mg·kg −1 ·bw). ADIs for THI, CLO, and PYR were 0.08, 0.1, and 0.03 mg·kg −1 ·bw, respectively [ 32 ].…”

Residue and risk assessment of fluopicolide and cyazofamid in grapes and soil using LC-MS/MS and modified QuEChERS

“…Up until now, there have been several reports on the determination of either uopicolide and its metabolites or cyazofamid and its metabolite. Sample pretreatment methods, such as solid phase extraction (SPE), [12][13][14][15] disperse solid phase extraction (d-SPE), [16][17][18] liquid-liquid extraction, 19 direct injection 20 and gel permeation chromatography (GPC) 19 have been reported. So, it is feasible to detect both the parent material and metabolites in different matrices.…”

“…However, there have been a few studies that have reported the simultaneous determination of fluopicolide, cyazofamid and their metabolites (M-01, M-02, and CCIM). In addition, the reported pretreatments are too time-consuming, 19 complicated and expensive because of the need for a large volume of solvent 13 and clean-up materials, such as Florisil. 14,15 …”