福建鹫峰山脉土壤有机氯农药分布特征及健康风险评价

采集福建鹫峰山脉81个表层土壤样品,利用气相色谱(GC-ECD)分析其中有机氯农药(OCPs)的含量,探讨该地区土壤中有机氯农药残留水平及分布特征,并采用美国EPA推荐的健康风险评价方法(USEPA 1991)对表层土壤中有机氯农药进行致癌风险评价.结果表明,土壤中HCHs和DDTs异构体或衍生物的检出率在77.78%~100.00%之间.HCHs及DDTs含量范围(平均值)分别为0.97~247.40 ng·g-1(10.17 ng·g-1)和0.01~384.75 ng·g-1(18.91 ng·g-1).与国内外相比,研究区土壤中OCPs含量属低污染区域.不同土地利用类型中,OCPs的残留依次为:水稻田>蔬菜地>茶叶地>林地.来源分析表明,研究区近期仍存在HCHs和DDTs输入,HCHs主要来源于林丹的使用,而DDTs可能与三氯杀螨醇的使用相关.风险评价结果显示,研究区表层土壤OCPs致癌风险值均在10-6~10-4之间,对当地居民基本不造成致癌风险.

Distribution Characteristics and Risk Assessment of Organochlorine Pesticides in Soil from Jiufeng Mountain Range in Fujian, China

Totally 81 surface soil samples were collected from Jiufeng Mountain Range, and 8 compounds of organochlorine pesticides (OCPs) were determined by a Ni electron capture detector (GC-ECD) to investigate the distribution, composition, source and potential health risks of these compounds in the study region. The detection ratio of HCHs and DDTs' isomers ranged from 77.78% to 100.00%. Concentrations of HCHs and DDTs in surface soils ranged from 0.97 ng·g^-1 to 247.40 ng·g^-1(mean 10.17 ng·g^-1) and 0.01 ng·g^-1 to 384.75 ng·g^-1(mean 18.91 ng·g^-1), respectively. Compared with other regions, the pollution of OCPs in Jiufeng Mountain Range stayed at a low level. The residue level in different types of lands was in the order as: paddy field>vegetable land>tea land>woodland. Source analysis indicated that Lindane and dicofol might be used recently in this area. The incremental lifetime cancer risks (ILCRs) of different age groups (children, youths, and adults) were all within the acceptable risk range of 10^-6 to 10^-4 recommended by USEPA for carcinogenic chemicals. The residue level of OCPs in soil may not cause cancer risk for local residents basically.