Abstract

Residue levels of bifenthrin were determined in unprocessed and processed okra fruits to evaluate the effect of different household processes on reduction of bifenthrin residues. Bifenthrin (commercial formulation) was applied at 25 g a.i. ha^-1 (single dose T₁) and 50 g a.i. ha^-1 (double dose T₂) in field. Okra fruits samples were collected on 0, 1, 3, 7, 10, 15 and 30 days and at harvest (60 days after treatment). Bifenthrin residues were estimated by gas chromatograph- electron capture detector (GC-ECD) system and reached below detectable level of 0.005 mg kg⁻¹ on 15 and 30^th day in single and double dose, respectively. Half-life period for bifenthrin were found to be 1.58 and 2.18 days at single and double dose, respectively following first order kinetics. Processing was found quite effective in reducing the levels of bifenthrin residues in okra fruits. Maximum reduction (64.58 to 68.42%) was observed by washing + boiling followed by washing (36.71 to 40.00%).

Key words: Bifenthrin, residues, Okra, half-life period, processing.