Degradation Dynamics and Final Residues of Pyridaben in Apples

The residue analysis method of pyridaben and its degradation dynamics and final residues in apples were studied. The pyridaben in apples were extracted by ether acetate and acetone(1∶ 1,V∶ V),and then purified by Florisil and concentrated,finally determined by GC with ECD-detector. The results showed that the limit of detection was estimated to be 1.0×10-11 g,the limit of quantification of pyridaben in apples was 0.02 mg/kg,the recoveries ranged from 83.6%~104.1% with a coefficient variation between 3.0%~4.3%,According to the investigation of the degradation dynamics and final residues in apples in two different areas of shandong province in 2006,the half life of pyridaben in apples was 4.1 days and 3.8 days,the final residues of pyridaben in apples was 0.059 and 0.040 mg/kg.