三种贮存方式对农残检测样品中有机氯类农药检测结果的影响

研究不同的贮存方式对蔬菜中有机氯类农药检测结果的影响。以生菜为实验材料，利用气相色谱技术对乙烯菌核利、联苯菊酯、甲氰菊酯三种农药在不同贮存条件（室温25℃、冷藏4℃、冷冻－20℃）下的残留量进行测定。研究表明，联苯菊酯稳定性高于甲氰菊酯和乙烯菌核利；贮藏3天时，室温贮存效果最好，三种农药残留率均在90%以上；贮藏5天时，冷冻贮藏效果好于冷藏；0.05mg/kg的残留浓度表现出更好的稳定性，残留率最高，贮存三天或五天后，残留率还有90%以上；随着样品冻融次数的增多，农药降解的速度加快，检测结果偏低，第3次冻融时，三种农药残留率不足70%，低于稳定与否的判定依据，因此贮存时应尽量在第三次冻融时完成检测。

Effects of three storage methods on the detection results of organochlorine pesticides in agricultural residue samples

The effects of different storage methods on the detection results of organochlorine pesticides in vegetables were studied. Using lettuce as experimental material, ethylene sclerotinic,bifenthrin Fenpropathrin three pesticides in different storage conditions The results showed that the stability of bifenthrin was higher than that of fenpropathrin and ethicillin; the effect of storage at room temperature was the best for 3 days, and the residue rates of the three pesticides were more than 90%; the effect of frozen storage was better than that of refrigeration for 5 days; the residue concentration of 0.05mg/kg showed better stability and higher residue rate The residue rate was more than 90% after storage for three or five days; With the increase of freezing and thawing times of samples, the degradation speed of pesticides is accelerated, and the test results are low. During the fourth freezing and thawing, the residue rate of three pesticides is less than 60%, which is lower than the judgment basis of stability or not. Therefore, the test should be completed during the third freezing and thawing as far as possible during storage.