Environmental and Food Safety Assessment of Emamectin Benzoate Residues on Apple Fruits: Field Efficacy of Emamectin Benzoate and Lufenuron against Codling Moth (Cydia pomonella L.)

Abstract

This study assessed the environmental and food safety implications of using Emamectin benzoate and the insect growth regulator Lufenuron for the management of codling moth, Cydia pomonella L., on Ibrahimi apple trees during the 2023-2024 growing season in Al-Husseiniya district, Karbala, Iraq. The work combined field efficacy evaluation with residue monitoring of Emamectin benzoate on apple fruits using high-performance liquid chromatography (HPLC), because pesticide performance should be interpreted together with residue persistence and consumer-safety considerations. Treatments differed significantly according to pesticide type, spray number, and post-treatment interval. Emamectin benzoate showed the highest rapid efficacy, reaching 62.83% after 7 days when means across sprays were considered and 67.66% after the second spray, whereas Lufenuron showed a delayed but sustained effect, with the highest efficacy of 58.33% after 28 days following the second spray. Residue analysis indicated that Emamectin benzoate deposits declined from 412.6 ug kg-1 at 1 h after spraying to 42.0 ug kg-1 by day 5, and residues were not detected by HPLC at day 7 and later intervals. The estimated half-life was 38.298 h. These findings indicate that Emamectin benzoate can provide rapid suppression of C. pomonella, while Lufenuron may serve as a delayed-action component in integrated pest management. From an environmental and food safety perspective, the rapid residue decline supports a suggested 7-day pre-harvest interval under the conditions of this experiment, provided that official maximum residue limits, method recovery, LOD, and LOQ are confirmed before final publication.