Residue patterns of buprofezin and teflubenzuron in treated peaches

The biological half-life and final residue levels of buprofezin and teflubenzuron were examined in peaches over a 14-day cultivation period. The residue levels of buprofezin and teflubenzuron were analyzed by chromatographic method with recovery ranging from 84.0% to 96.6%. The biological half-lives of buprofezin andteflubenzuron were 4.88 and 11.49 days at the standard dose, and 4.40 and 10.86 days at a triple dose, respectively. The initial concentration of buprofezin exceeded the maximum residue limit (MRL) set in Korea, but the concentration decreased to below the MRL within 6 days after application. The initial and persisting concentrations of teflubenzuron were all below the prescribed MRL. The final residue levels of buprofezin and teflubenzuron were 0.17 and 0.10 mg·kg﹣1 following a standard single dose, and 0.20 and 0.23 mg·kg﹣1 following a triple dose, respectively. The final re-sidue levels of buprofezin and teflubenzuron were also compared with the good agricultural practices standards of the United States and Italy.