茶叶及大米中有机氯农药残留量前处理方法的研究

Research on the Pretreatment Methods for Determination of Residual Organochlorine Pesticides in Tea and Rice

采用气相色谱法对茶叶和大米中的六六六、滴滴涕8种有机氯农药残留量进行测定,分析超声波提取法、机械振荡提取法和索氏提取法等三种前处理方法对测定结果的影响。结果表明:三种前处理方法中索氏提取法耗费的溶剂最多,时间最长,但提取率最高,是测定茶叶中有机氯农药残留量的一种可靠方法,特别适合于能力验证。

The gas chromatographic method was adopted for determining the amounts of residues of 8 kinds of organochlorine pesticides such as benzene hexachloride(BHC),DDT,etc.in tea and rice,and the influence of three pretreatment methods,i.e.,ultrasonic extraction,mechanical oscillation extraction and soxhlet extraction on the determination results was analyzed.The results show that,among the three methods,the method of soxhlet extraction has the highest solvent consumption and the longest time,but has highest extraction rate.It is a reliable method for the determination of organochlorine pesticide residues in tea,and is especially suitable for the capability verification.