温室中有机氯农药残留及其对映体选择性研究

Residues and enantioselectivity of organochlorine pesticide from greenhouse

以杭州市某温室蔬菜基地为例,对温室环境中土壤、地膜以及茄子、黄瓜与辣椒三种温室蔬菜组织中有机氯农药(Organochlorine pesticides,OCPs)的残留和来源状况进行分析,并对污染物在温室环境中的归趋进行探究.结果表明:温室土壤、地膜和蔬菜组织中滴滴涕(DDTs)的残留量均值分别为26,39,15ng/g;六六六(HCHs)为4.9,8.5,2.8ng/g;氯丹为2.0,1.8,0.68ng/g,地膜的OCPs平均残留质量分数最高.残留组成分析表明:温室土壤都曾受到过DDTs、HCHs和氯丹的污染,但不存在大量的新污染源.对映体分数分析结果同样表明温室中不存在DDTs和HCHs的新污染源.各类OCPs中,DDTs在蔬菜组织中的质量分数最高,其次为HCHs和氯丹.

This work investigated the pollution sources and the transport trend of organochlorine pesticides （OCPs） in greenhouse soils, agricultural films, eggplants, cucumbers and peppers in greenhouse farm in Hangzhou. The mean concentrations of dichlorodiphenyltrichl0roethanes （DDTs） in soils, agricultural films and vegetables were 26 ng/g, 39 ng/g and 15 ng/g, respectively. The mean concentrations of hexachlorocyclohexane （HCHs） were 4. 9 ng/g, 8. 5 ng/g, and 2. 8 ng/g for soils, agricultural films and vegetables, respectively. The mean concentrations of chlordane were 2.0 ng/g, 1.8 ng/g and 0.68 ng/g for soils, agricultural films and vegetables, respectively. The results showed that greenhouse soils have been po!luted by chlorophenothane （DDT）, hexachlorocyclohexane （HCHs） and chlordane in history and no new obvious pollution source of OCPs in these greenhouses. The results of enantiomer fraction analysis also showed that there was no new pollution source of HCHs and DDTs in greenhouses. DDTs have the highest concentration in vegetable tissues, and followed by HCHs and chlordane.