Vol. 11, Special Issue 5 (2022)

Author(s):
IR Bagwan, KG Patel, S Singh, LV Ghetiya, KD Bisane, LK Saini, VH Solanki, KD Gandhi, RV Kansara and YA Garde

Abstract:
A simple, sensitive and reproducible analytical method, an efficient triple quadrupole mass spectrometer used for the quantification of indoxacarb residues in sapota fruit under South Gujarat conditions was validated using LC-MS/MS. The validated method was linear (0.001-0.25 µg/ml) having correlation coefficients (R²) value lyinges 0.998 to 0.999. The LOD and LOQ were 0.001 and 0.004 µg/g, respectively. Modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction technique involved for extraction of indoxacarb residues with 1% acetic acid in acetonitrile provided acceptable recoveries in the range of 98.63 ± 6.20 to 100.50 ± 1.21 per cent at 0.01, 0.05 and 0.10 µg/g spiking level with precision relative standard deviation (RSD) range from 1.20 to 6.29 per cent. Initial deposit on sapota fruits following two application (15 days interval between application) of indoxacarb 14.5% SC at 145 and 290 g a i/ha was 0.203 µg/g and 0.243 µg/g and dissipated to 0.009 and 0.015 µg/g, respectively, on 10 days after application during 2019-20 and 2020-21. Half-life were 2.15 and 2.51 days, safe waiting period (SWP) on the basis of Codex MRL (0.02 µg/g) limit were ranged from 7.17-9.05 days for RD and 9.42-10.27 days for 2 x RD respectively, for the year 2019-20 and 2020-21. As per European Union (EU) and United States (US) MRL values (1 µg/g) at RD and 2 x RD the residues of indoxacarb were found below MRL on day 0 during both years under South Gujarat conditions. Dietary risk assessment (Risk quotient <1) was performed on the basis of field trial suggested that application of indoxacarb at recommended dose 14.5% SC at 145 g a i/ha is safe for the consumers.