Dissipation of fenazaquin in brinjal fruits and its cultivated soil

Persistence and dissipation of fenazaquin (10% EC) was investigated in brinjal fruits and soil using high performance liquid chromatography (HPLC) and confirmed with liquid chromatography mass-spectrometry (LC-MS). The average initial residues of 0.046, 0.098, 0.174 and 0.048, 0.102, 0.170 mg kg⁻¹ were recorded during 1^st and 2^nd year, respectively, on brinjal fruits after application of fenazaquin @ 25, 50 and 125 g ai ha⁻¹. Dissipation followed first order kinetics with half-lives ranging from 0.65 to 1.78 days at all application rates. Residues reached below the LOQ (<0.01 mg kg⁻¹) after 3^rd, 5^th and 7^th day at all three application rates during 1^st and 2^nd year. Residues of fenazaquin in soil samples collected from brinjal field after 15 days of third application, were below LOQ after application of fenazaquin at all the three doses during both the years of the study, respectively. Based on the study, a 4-day waiting period is recommended to reduce the risk before the consumption of brinjal fruits.