LC-Q-TOF/MS快速筛查茶叶中26种高毒剧毒农药

Rapid determination of 26 high toxic and poisonous pesticides in tea by LC-Q-TOF/MS

建立了无需标准品对照定性筛查茶叶中26种高毒剧毒农药的液相色谱-四级杆/飞行时间质谱检测方法。在20,50,100μg/kg 3个添加水平下,88.5%的农药平均回收率在70%~120%范围内且相对标准偏差（RSD）≤20%（n=5）。采用本方法对市售6大类77种茶叶进行检测,有5种绿茶检出了高毒农药,占样品总数的6.5%,未检出剧毒农药。检出的高毒农药有三唑磷、水胺硫磷和克百威。白茶、红茶、花茶、普洱茶、乌龙茶中均未检出高毒剧毒农药。方法适用于茶叶中高毒剧毒农药残留的快速检测和日常监控。

A novel method for determination of 26 high toxic and poisonous pesticides without reference standards by liquid chromatography coupled time-of-flight mass spectrometry（ LC-Q-TOF / MS） was established. At three spiked levels of 20,50,and 100 μg / kg,mean recoveries for the majority of pesticides（ 88. 5%） ranged from70% to 120% in tea with relative standard below 20%. Finally,this method has been applied to investigate the26 high toxic and poisonous pesticide residues in 6 categories of 77 kinds of tea purchased from markets in Beijing. High toxic pesticides were detected in 5 of 77 tea samples accounted for 6. 5% of the total number of samples. None of all samples tested showed any poisonous pesticide residue. 3 high toxic pesticides including carbofuran,isocarbophos,and triazophos were detected in 5 types of green tea only. No pesticides were detected in white tea,black tea,flower tea,puer tea,and oolong tea. The method is effective and easy,which can be applied to rapid determination and daily monitor of high toxic and poisonous pesticides in tea.