Dissipation patterns of acrinathrin and metaflumizone in Aster scaber

Abstract

The establishment of preharvest residue limits (PHRLs) is important to minimize damage to producer and consumers caused by agricultural products which pesticide residue exceeds maximum residue limits (MRLs). Dissipation patterns of acrinathrin and metaflumizone in Aster scaber in greenhouse were studied during 10 days in order to determine a pre-harvest interval after application. Acrinathrin and metaflumizone were applied in two different greenhouse, located in Taean-gun (field 1) and Gwangyang-si (field 2). Samples were collected at 0, 1, 2, 3, 5, 7, and 10 days after insecticides application. The recoveries of two insecticides analyzed by LC–MS/MS and HPLC–DAD were ranged from 77.1 to 111.3%. The half-lives of acrinathrin and metaflumizone residues respectively were 3.8 and 5.9 days in field 1 and 9.2 and 4.5 days in field 2. The PHRLs 10 days before harvesting A. scaber were 0.610 mg/kg (field 1), 0.946 mg/kg (field 2) for acrinathrin, and 5.930 mg/kg (field 1), 5.147 mg/kg (field 2) for metaflumizone. This results can be used as basic data for the establishment of PHRL in A. scaber.

Insecticides chlorantraniliprole and flubendiamide in Aster scaber: Dissipation kinetics, processing effects, and risk assessment

“…The dissipation proportions of CAP and FBD over 10 days were 60–68 % and 53–64 %, respectively. Similarly, the dissipation proportions of acrinathrin and metaflumizone in A. scaber were reported to be 56–83 % [ 24 ]. According to the GAP guidelines, the recommended PHI is 7 days for both CAP and FBD.…”

“…Therefore, the slower dissipation of pesticide residues in A. scaber than in other crops may be attributed to its lower enzymatic degradation capacity, resulting in prolonged persistence. Previous research has reported longer half-lives in A. scaber , such as 3.8–9.2, 4.5–5.9, 8.5, 5.8, and 7.6 days for acrinathrin, metaflumizone, methoxyfenzide, novaluron, and pymetrozine, respectively, which were determined by excluding any potential dilution effect [ 24 , 36 , 37 ]. These results are consistent with those of the present study.…”

“…If the degradation of the pesticide agreed with pseudo-first-order kinetics [ [23] , [24] , [25] ], the dissipation constant (λ) of the pesticide in A. scaber was determined using the following equation: where C t is the concentration of the pesticide at time t (day), C 0 is the initial concentration at 0 DATs, and λ is the dissipation constant (day −1 ). The mean and 95 % confidence interval (95 % CI) of the dissipation constant (λ) were calculated using regression analysis after evaluating the time-dependent residues of pesticides using the F-test and regression coefficient (R 2 ).…”

“…The PHRLs of the pesticides were estimated based on the 95 % upper confidence limit (95 % UCL) of the dissipation constant (λ) and MRLs in A. scaber using the following equation [ 24 , 26 ]: where the MRL in A. scaber is 7 mg/kg for CAP and 20 mg/kg for FBD [ 27 ].…”