有机氯农药（OCPs）是一类重要的持久性有机污染物（POPs），具有半挥发性、持久性和高毒性，并能通过食物链富集，危害生态系统和人体健康。有机氯农药可以在不同的环境介质间迁移，并能在大气环境中进行远程输送，导致大范围乃至全球性的环境污染。最近的研究发现太湖地区的有机氯农药含量仍然非常高，为了了解太湖有机氯农药的来源以及环境行为，采用气相色谱质谱法对太湖竺山湾水体和沉积物样品中有机氯农药（OCPs）含量进行了测定，探讨了太湖水体和沉积物中有机氯农药的可能来源以及水体-沉积物之间的交换通量。研究结果表明：沉积物样品中的六氯苯的含量最高，为2.33 ng·g-1（干质量，下同），其次为p,p’-DDT、p,p’-DDE和β-HCH，含量分别为0.67、0.64和0.37 ng·g-1。从水体中OCPs的组成来看，p,p’-DDT的含量最高为426.26 pg·L-1，其次是α-HCH和硫丹Ⅰ，含量分别为289.99和215.20 pg·L-1。采用α-HCH/γ-HCH比值对HCHs的来源进行分析，发现太湖水体中的γ-HCH污染来源于工业品六六六和林丹的使用，由交换模型得出HCHs的净交换通量为释放通量，表明HCHs的迁移方向是由沉积物到水中，沉积物的释放已成为太湖水体中HCHs的主要来源之一。水体中的p,p’-DDT/p,p’-DDE比值远大于1，而且由交换模型得出p,p’-DDT的净交换通量为沉降通量，说明了近期可能有新的污染源的输入。值得注意的是，硫丹Ⅰ的净交换通量同样为沉降通量，反映出太湖水体中硫丹Ⅰ可能存在新源的输入。%Organochlorine pesticides (OCPs) are important persistent organic pollutants (POPs), Because of their half-volatility, persistence, and high toxicity in the environment and biological accumulation through the food web, OCPs have done great harm to the environment and human health. OCPs are able to migrate between the different environmental media, proceed to long-range transport in the air, and lead to global environmental problems. High level of OCPs in the Taihu Lake Region was reported by the latest research. In order to understand the sources and the environmental behaviors of these OCPs in the Taihu Lake, the contents of OCPs in both water and sediment samples from Zhushan Bay of Taihu Lake were determined by GC-MS. The potential sources and water-sediment exchange flux of OCPs was discussed. The results indicated that HCB were the most dominant compounds in the sediment, and the content was 2.33 ng·g-1 (DW). Relative higher contents of OCPs werep,p’-DDT,p,p’-DDE andβ-HCH, the contents were 0.67 ng·g-1, 0.64 ng·g-1 and 0.37 ng·g-1, respectively. It can be seen from the OCPs in Taihu Lake water samples, the highest content ofp,p’-DDT was 426.26 pg·L-1, followed byα-HCH and endosulfan which contents were 289.99 pg·L-1 and 215.20 pg·L-1. According to ratio ofα-HCH/γ-HCH and HCHs source analysis, it can be found that HCHs pollution in Taihu Lake came from the use of industrial HCHs and lindane. The net exchange flux of HCHs were release fluxes, indicating the tendency to transfer these contaminants from sediment to water. This implies that the residue of HCHs in the lake sediment might have been an important source of HCHs to the water. The ratio ofp,p’-DDT/p,p’-DDE in water bodies is much larger than 1, and the net exchange flux of p,p’-DDT were deposition fluxes, indicating the new sources of input. It is notable that the fluxes for endosulfan I also followed the same pattern asp,p’-DDT, reflecting there were probably new sources to the Taihu Lake.
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