江阴市大气PM_(2.5)中有机氯农药的残留水平、空间分布及来源分析

Residue Level,Spatial Distribution and Source of Organochlorine Pesticides in Atmospheric PM_(2.5) in Jiangyin City

于2013年秋季利用大流量采样器采集了江苏省江阴市大气PM_(2.5)样品,使用气相色谱质谱连用仪(GCMS)检测了19种有机氯农药(OCPs),对其残留水平、空间分布及来源进行分析。结果显示,江阴市大气PM_(2.5)中19种OCPs的总质量浓度平均值为2.84 ng·m-3,主要成分为HCHs、DDTs、工业氯丹以及甲氧氯,分别占OCPs总量的48.2%、19.7%、12.3%和12.5%。与国内外其他地区比较,江阴市大气中有机氯农药污染水平属中等偏上。OCPs空间分布趋势表现为环境监测中心OCPs污染水平最高,而申港公园污染水平最低。来源分析表明,江阴市大气PM_(2.5)中DDTs和氯丹均来源于历史残留;HCHs既来源于工业HCHs的历史残留,同时又存在大量林丹的输入。

Atmospheric PM_(2.5)samples were collected in different functional areas of Jiangyin,Jiangsu Province with high volume sampler in the autumn of 2013,for analysis of concentrations of 19 kinds of organochlorine pesticides( OCPs) with GC-MS in an attempt to determine residue level,spatial distribution and source of the pollutants. Results show that the mean total concentration of ∑OCPs in PM_(2.5)was 2. 84 ng·m-3. Among the 19 kinds of OCPs,HCHs,DDTs,chlordanes and methoxychlor were the dominant ones in the PM_(2.5),accounting for 48. 2%,19. 7%,12. 3% and 12. 5%,respectively.Compared with the atmospheres in other regions either domestic or abroad,the one in Jiangyin was moderate by the upper side in OCPs pollution level. The OCPs spatial distribution tendency map shows that the pollution level is the highest in the Environmental Monitoring Center,and the lowest in the Shengang Park. Source analysis reveals that DDTs and chlordane in the PM_(2.5)came from historical residue pollution,while HCHs did from both historical residue of industrial HCHs and recent input of large volumes of lindane.