Residue Determination Of Chlorpyifos In Apple Fruit, Leaf And Orchard Soil

Experiment was conducted to investigate the residual dynamic of chlorpyrifos of'Gala'apple's fruit, leaf and soil in orchard by GC-TSD in shaanxi main apple field. The organic phosphorus pesticide chlorpyrifos was selected. Main results in this study are listed as follows:1. The better recovery rate and RSD could be obtained by GC-TSD and ameliorating the predisposal method of sample, and could satisfied the request of pesticide residues determination on fruit, leaf and soil. Fruit sample was distilled by Myclobutanil as impregnant. The recovery rate was in the range of 87.1%-102.3%, and RSD was 4.3%-6.4%, and the lowest detectable concentration of method was 0.0120mg/kg; leaf sample was determined by cleaned-up with Florisil columns and 40ml acetone +oil aether (10%+90%) as filter solution, the rate of filter was 2ml/min. In this way, the preparation sample's pesticide residues component could be ration reclaimed, and interfere of preparation sample determination by virtue of leaf pigment was eliminated. The recovery rate was in the range of 85.48%-88.73%, and RSD was 3.3%-4.6%; soil sample was distilled by ultrasonic surge. The recovery rate was in the range of 92.6%-100.1%, and RSD was3.4%-4.5%. The results showed that the distilled method, detected method and conditions were suitable for this experiment, and the accurate data could be acquired, and could be used to detection of chlorpyrifos.2. Determination of fruit's pesticide residues indicated that the pesticide residues and rate of dissolution of peel was greatest, the different position is: apple> pulp> core. There were no significant difference in residues half life between two different concentrations of chlorpyrifos, was average about 25d, respectively. The ultimately pesticide residues was 0.065mg/kg in concentration of 1∶1 000, and was 0.041mg/kg in 1∶2 000.3. Determination of leaf's pesticide residues indicated that pesticide residues were the most on the day of chlorpyrifos insufflations. In second day, the rates of dissolution were exceeded by 60 % in two different concentrations, the rates of dissolution of high concentration were greater than that of low concentration. With the increase of interval times,...