Residue Analysis and Field Residue Decline Studyof Triazophos in Bamboo Shoot

Triazophos residues in bamboo shoot were analyzed with gas chromatography (GC-FPD),and the decline equation of triazophos residue in bamboo shoot was established.Bamboo shoot was shattered and extracted with acetonitrile.Then the clean-up solution was injected into DB-1701 chromatogram column and analyzed by GE-FPD.The fortified recovery at level of 0.01 ~0.1 mg/kg ranged from 94.0％ ~101.5%,with relative standard deviation of 1.6% ~18.2%.The limit of detection of triazophos by the method was 5×10-12 g,and the limit of quantification for triazophos in bamboo shoot was 0.01 mg/kg.The field residue decline study demonstrated that: 1) The absorption of triazophos reaches the highest 1 day after treatment,and then the residue declined slowly.After 30 days,the residues of triazophos was found to be around the limit of quantification.The half-life of triazophos was 3.7 days in bamboo shoot.2) The decline equation of the residue of triazophos in bamboo shoot was ct=2.738 5e-0.186 t .It's recommended that the pre-harvest interval (PHI) of triazophos on bamboo shoot set to be 21 days.