福建茶园茶叶中六六六和滴滴涕残留水平及来源分析

运用气相色谱-电子捕获检测器（GC-μECD）分析了福建茶园茶叶中六六六（HCHs）和滴滴涕（DDTs）等有机氯农药（OCPs）的分布、组成和来源。结果表明,∑OCPs浓度为0.764～10.561ng.g-1,永泰最高,福鼎最低,一般而言,老叶中∑OCPs浓度高于嫩叶;∑HCHs浓度为0.373～7.427ng.g-1,永泰最高,政和最低,老叶中HCHs浓度显著高于嫩叶;茶叶中HCHs同系物以γ-HCH为主,占总量的51.3%～94.1%;α-/γ-HCH表明所有茶园均存在林丹的使用或输入,β-（/α＋γ）-HCH表明所有茶园均非HCHs历史污染,可能存在HCHs其他新的来源。∑DDTs浓度为0.123～5.168ng.g-1,政和最高,福鼎最低,老叶和嫩叶中无显著差异;与土壤类似,茶叶中DDTs同系物以p,p′-DDT和o,p′-DDT为主,两者之和占总量的67.3%～96.0%;p,p′-DDE/p,p′-DDT表明,除福鼎、永泰和安溪外,其他茶园均存在工业DDTs的使用或输入;o,p′-DDT/p,p′-DDT表明,除政和外,其他茶园均存在大量的三氯杀螨醇的使用或输入,以安溪较为严重。

Residues and Sources of HCHs and DDTs in Tea Leaves in Fujian Tea Gardens

Seven tea gardens in Fuding（FD）,Fuzhou（FZ） and Yongtai（YT） in the east,Anxi（AX） in the south,Shanghang（SH） in the west,Zhenghe（ZH） in the north,and Youxi（YX） in the middle of Fujian Province were selected,and GC-μECD was employed to determine the concentration,the composition and the source of the organochlorine pesticides（OCPs）,such as HCHs and DDTs in tea leaves.The results showed that the concentrations of ∑OCPs ranged from 0.764 ng·g-1 to 10.561 ng·g-1,with the highest in YT and the lowest in FD.Generally,∑OCPs in old leaves were higher than those in new leaves.∑HCHs ranged from 0.373 ng·g-1 to 7.427 ng·g-1,with the highest in YT and the lowest in ZH.Generally,∑HCHs in old leaves were significantly higher than those in new leaves.γ-HCH accounted for the highest ratio to the total HCHs in tea leaves,with the values of 46.9%~93.9%.The ratios of α-/γ-HCH suggested the newly input or use of lindane in all the tea gardens,and the ratios of β-/（α＋γ）-HCH implied that they were no historic pollution but new sources of HCHs in all the tea gardens.∑DDTs ranged from 0.123 ng·g-1 to 5.168 ng·g-1,with the highest in ZH and the lowest in FD.They were no significant variances between old leaves and new leaves for ∑DDTs.Similar to those in soils,the main isomers were o,p＇-DDT and p,p＇-DDT for all the DDTs isomers,with the ratios of 67.3%~96.0%.The ratios of p,p＇-DDE/p,p＇-DDT suggested the use or input of technical DDTs in the tea gardens except for those in FD,YT and AX.The ratios of o,p＇-DDT/p,p＇-DDT indicated that large amount use or input of dicofol in the tea gardens except for those in ZH,especially in AX.