有机氯农药在茶叶及其环境中的残留状况与评价

Residual dynamics and evaluation of BHC and DDT in tea and its enviromments

调查结果表明，有机氯农药全面禁用十多年后，在调查区内灌溉水—土壤—茶叶系统中，六六六的检出率达９０％以上，其在体系中的残留形态是以β－六六六为主．ＤＤＴ在体系中的检出率达１００％，其在土壤和灌溉水中是以ＯＰ－ＤＤＴ和ＰＰ－ＤＤＤ为主，而茶叶中是以ＰＰ－ＤＤＴ和ＯＰ－ＤＤＴ为主，并且ＤＤＴ在体系中的残留量均大于六六六．它们在茶体和茶叶中的残留分布规律，六六六为春茶＞秋茶＞暑茶＞夏茶，新叶＞老叶＞茎＞根；而ＤＤＴ为春茶＞暑茶、夏茶、秋茶，新叶＞根＞茎和老叶．在调查区的茶叶中六六六、ＤＤＴ的残留问题，按我国茶叶食品卫生标准评价，大多数为轻度残留和近于消除残留．

The residual quality of BHC and DDT in tea, the soil of tea plantation and the irrigation water was studied when the application of BHC and DDT had been prohibited for more than ten years. BHC was found in 90% of the above samples withβ-BHC isomer being the main residual form.DDT existed in all the samples of which the main residual form was OP-DDT and PP-DDT.The residual quality of DDT was always higher than that of BHC. The residual distribution tendency of BHC was spring tea>autumal tea> late summer tea> summer tea for the tea and young leaves> old leaves > stem>root for the tea plants.The residual distribution tendency of DDT was in spring tea > late summer tea> summer tea, and autumn tea for the tea and young leaves>root>stem and old leaves for the tea plants.