SUMMARY
Brinjal (Solanum melongena) is a versatile crop infected by several insects and pests. For the control of these pests, spiromesifen insecticide has been in use to reduce the damage and increase crop production worldwide. Therefore, a field trial was conducted to study dissipation and persistence behavior of spiromesifen 22.9% w/w SC in/on brinjal at the recommended dose (RD) 96 g a.i./ha and double to recommended dose 192 g a.i./ha (2RD). The quantitative analysis of spiromesifen was performed using ultra-high performance liquid chromatography- tandem mass spectrometry (UHPLC-MS/MS). Samples were processed by the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method. The analytical method was validated using various parameters viz., linearity (R2=0.99), sensitivity (LOD and LOQ), accuracy (recovery=70-120%) and precision (RSD=20%). The spiroemsifen persisted up to 3 days at RD and 5 days at 2RD. The dissipation half-life (DT50) of spriromesifen was 3.64 and 4.10 days at RD and 2RD in brinjal, respectively. However, residues of spiromesifen measured from soil at 0th (2 hr) day and 10th day were below the limit of quantification (BQL). The waiting period deciphered for spiromesifen applied in brinjal was 1 day at the recommended dose. Further, health risk assessment (health risk index<1 and percent health index<100) was performed on the basis of field trial which suggested that the application of spiromesifen in brinjal crop at recommended dose is safe for the end-users.