福建沿海海岛大气颗粒物中有机氯农药的区域背景及污染特征

为了研究沿海海岛背景区大气OCPs（有机氯农药）污染特征，于福建东山岛采集大气颗粒物样品，分析其中20种OCP化合物的质量浓度及可能来源.结果表明:东山岛大气颗粒物中ρ（总OCPs）为0.05~13.24 pg/m3，平均值为（3.21±2.78）pg/m3.其中，ρ（HCH）（HCH为六六六）最高，占ρ（总OCPs）的50.2%，其次是ρ（甲氧DDT）（甲氧DDT为甲氧滴滴涕）、ρ（DDT）（DDT为滴滴涕）和ρ（异狄氏剂），而ρ（氯丹）、ρ（硫丹）、ρ（艾氏剂）和ρ（狄氏剂）均较低.ρ（总OCPs）季节性变化特征明显，表现为春季>冬季>夏季.OCPs分子标志分析显示，冬季和春季东山岛存在林丹新源的输入，夏季存在DDT新源的输入，而氯丹和硫丹主要以历史残留为主.与其他区域相比，东山岛大气颗粒物中ρ（总OCPs）明显低于城市、工业、农业、郊区、陆地背景区以及欧洲沿海背景区，总体处于较低水平.按功能区分化，OCPs的污染特征表现为城市、工业和农业区域>郊区、陆地背景区>海洋背景区.气团后向轨迹分析显示，春季ρ（总OCPs）较高可能受到北方陆地污染气团来源的影响，而夏季ρ（总OCPs）较低主要受到洁净海洋气团来源的影响.研究显示，福建沿海海岛背景区域大气中OCPs受污染源影响较小，其赋存状态处于较低水平. 

Regional Background and Pollution Characteristics of Organochlorine Pesticides in Atmospheric Particles on the Coastal Island of Fujian Province

The background area of the coastal island, located in the junction of the ocean and land, is an important region for studying how POP enters the ocean through the atmosphere. To investigate the Organochlorine Pesticides (OCPs) pollution characteristics in the coastal background area, atmospheric particulate samples were collected from Dongshan Island in Fujian Province over a 1-year period. The ρ(total OCPs) and possible sources were analyzed on the coastal island. The results showed that ρ(total OCPs) ranged from 0.05-13.24 pg/m3, with an average of (3.21±2.78) pg/m3. HCH was the main component of OCP in the atmospheric particles, followed by Methoxychlor, DDT and Endrin, while the levels of Chlordane, Endosulfan, Aldrin and Dieldrin were relatively low. Obviously, seasonal variation of ρ(total OCPs) was observed, which exhibited higher levels in winter and spring, and lower levels in the summer time. Source apportionment indicated that fresh lindane input may occur during the winter and spring, and fresh DDT input in summer, while Chlordane and Endosulfan were mainly historical residue. Compared with other regions, the ρ(total OCPs) levels were obviously lower than those in urban, industrial, agricultural, suburban, land background and European coastal background areas. The backward trajectories were used to analyze the effects of pollutant transport, and the results indicated that the higher OCP concentration in spring was likely to be influenced by the air masses from the northern land in China, while the source of clean marine air masses was likely to be responsible for the lower OCP concentration in summer. The study indicated that the OCPs in atmosphere of the coastal island at Fujian Province were less affected by pollution sources, and the ρ(total OCPs) were relatively low.