福建省漳江口表层沉积物中滴滴涕的残留特征

采用GC-ECD方法分析了漳江口表层沉积物样品中滴滴涕（DDTs）的残留量,并对其来源和生态风险进行了分析与评价。结果表明,沉积物中DDTs的残留量平均为16.4 ng·g^-1,其4种异构体p,p′-DDE,p,p′-DDD,o,p′-DDT,p,p′-DDT的平均残留量分别是4.12ng·g^-1,9.54 ng·g^-1,0.529 ng·g^-1和2.26 ng·g^-1。DDTs沿漳江呈波浪型分布,至佳洲岛分流前DDTs的残留比较高。组成特征显示DDTs主要为环境中的早期残留,且多为厌氧性生物降解,而在Z9站（江心岛后）近期可能有新的DDTs输入。与其它地区相比,漳江口表层沉积物中的DDTs残留属于中等水平。生态风险评价结果显示,86.7%的样品DDTs含量超过风险评估低值（ERL）,13.3%样品的含量超过风险评估中值（ERM）,说明存在较高的生态风险,对生态环境已造成一定的危害,必须引起重视。

Residual characteristics of DDTs in surface sediments from the Zhangjiang River estuary of Fujian

Residues of DDTs in surface sediments from the Zhangjiang River estuary were analyzed by GC-ECD. The possible sources and potential risks were assessed. The results showed that the mean concentration of DDTs was 16.4 ng.g- 1. Average concentrations of the four isomers, namely DDT, p, p'-DDE, p, p'-DDD, o, p'-DDT and p, p'-DDT, were 4.12 ng.g-1, 9.54 ng.g-1, 0.529 ng.g-1 and 2.26 ng.g-1, respectively. The concentrations of DDTs were observed waving along the Zhangjiang River, while higher concentration occurred at Jiazhou Island, the upstream location before Zhangjiang River divaricated. From the analysis of composition profile, DDTs mainly came from the early residues, products from anaerobic biodegradation. However, new DDTs inputs might happen recently at the Z9 station, a station downstream after the ait. Compared to other areas, the residues of DDTs in the Zhangjiang River estuary were at the medium level. The result of ecological risk assessment revealed that 86.7% of samples had higher DDTs contents than that of Effects Range-Low (ERL), while 13.3% of samples had higher contents than that of Effects Range-Median (ERM). The results showed that high ecological risk existed in this area.