A large number of pesticide and chemical plants have been moved out of southern Jiangsu province for nearly ten years. In order to understand the residue and the environmental behaviors of OCPs in this area, it was the first time to study the distribution characteristics of 22 organochlorine pesticides (OCPs) in shallow soil from some agricultural and industrial areas located in Nanjing, Zhenjiang, Changzhou, Wuxi and Suzhou. 30 samples collected from different depths were extracted using accelerated solvent extraction (ASE) and analyzed by gas chromatography equipment with electron capture detector (ECD). Research results indicated that the topsoil was still the major residual layer for organochlorine pesticide. DDTs and HCHs were the primary pollutants of OCPs in the samples. Concentrations of DDTs and HCHs in topsoils ranged from n.d. to 313.0 ng·g-1 with a mean value of 75.04 ng·g-1 and n.d.~9.25 ng·g-1 with a mean value of 2.82 ng·g-1, respectively. p,p′-DDD and p,p′-DDE were found to be the major components of DDTs, andβ-HCH were found to be the major components of HCHs. In addition, HCB, Aldrin, Heptachlor, Dieldrin, Endosulfan sulfate were also detected in varying degrees. Concentrations of OCPs varied according to the different land use patterns. The highest residues of DDTs were found in the industrial area, while HCHs were the prominent OCPs in agricultural areas. The mean concentrations of OCPs were in the order:industrial areas (127.2 ng·g-1)>agricultural areas (30.75 ng·g-1). Due to the influence of anthropogenic activities, concentrations of OCPs, DDTs and HCHs in most sampling sites tended to decrease gradually from topsoil to bottom layer, while there were some slight fluctuations in decreasing process in some sampling sites. Compared with the undetectable levels of γ-HCH, only a few α-HCH had been found in soil samples, indicating that there was no recent input of Lindane and HCHs. The value of (p,p′-DDD+ p,p′-DDE)/DDTs indicates that there was less contamination input from the new contamination recently in this area. The results provide some references for the vertical profile of OCPs in this region.%近10年来，大批农药、化工企业迁出江苏南部地区，为了解该地区有机氯农药的残留状况以及环境行为，首次对南京、镇江、常州、无锡、苏州部分农业区和工业区浅层土壤中22种有机氯农药（OCPs）的分布特征进行研究，采用加速溶剂萃取法（ASE）和气相色谱法（GC-ECD），对30个不同深度样品进行检测。结果表明：表层土壤依旧是OCPs的主要残留层，主要为滴滴涕（DDTs）和六六六（HCHs）类污染，其中，ω(DDTs)为ND~313.0 ng·g-1（干重，下同），平均值75.04 ng·g-1；ω(HCHs)为ND~9.25 ng·g-1，平均值2.82 ng·g-1。DDTs残留以降解代谢产物p,p′-DDD和p,p’-DDE为主，HCHs残留则以β-HCH为主。此外，六氯苯（HCB）、艾氏剂（Aldrin）、七氯（Heptachlor）、狄氏剂（Dieldrin）和硫酸硫丹（Endosulfan sulfate）也有不同程度检出。不同利用类型表层土壤中，有机氯残留状况有所差异，DDTs 在工业区土壤中残留量最高，而HCHs在农业区土壤中残留量最高，OCPs残留平均值为工业区（127.2 ng·g-1）>农业区（30.75 ng·g-1）。垂向土壤样品分析结果表明：大部分点位OCPs、DDTs及HCHs的残留量均随土壤深度增加而降低，但在下降过程中存在一定的波动性，由于场地土壤受到人为活动的影响，存在一定的干扰现象。本次调查未检出γ-HCH，仅有少量α-HCH检出，说明这些地区近期未出现林丹和HCHs输入。样品中(p,p′-DDD+p,p′-DDE)/DDTs的比值显示该地区近期新的外源DDTs输入较少。本次调查提供的数据可为该地区OCPs垂直分布研究提供参考。
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