Minh Nguyen Hung, Minh Tu Binh, Iwata Hisato, Kajiwara Natsuko, Kunisue Tatsuya, Takahashi Shin, Viet Pham Hung, Tuyen Bui Cach, Tanabe Shinsuke
Center for Marine Environmental Studies, Ehime University, Matsuyama, Japan.
Arch Environ Contam Toxicol. 2007 May;52(4):458-65. doi: 10.1007/s00244-006-0157-5. Epub 2007 Mar 9.
Surficial sediment samples were collected from Hochiminh City canals, the Sai Gon-Dong Nai River, and its estuary, one of the most predominant industrial areas in Hochiminh City, southern Vietnam, for determination of selected persistent organic pollutants (POPs). Contamination pattern was as follows: PCBs > or = DDTs > HCB > CHLs > HCHs. Concentrations of PCBs and DDTs ranged from 0.50-150 ng/g and 0.15-72 ng/g dry wt, respectively. On the other hand, concentrations of CHLs, HCHs, and HCB were mostly <2 ng/g dry wt. Levels of the all organochlorines (OCs) in Hochiminh City canals were significantly higher than those in the other areas, indicating the urban areas as major pollution sources to the aquatic environment. The contamination pattern was PCBs > DDTs in the city canals but PCBs < DDTs in the downstream and the estuary, suggesting particularly high contamination by PCBs in the city. Examination of DDTs composition and their ratios demonstrated continuous input of this pesticide to the city canals. However, the combination of our data and those from available literature implies a decreasing trend of PCBs and DDTs in the environment. DDTs concentrations have been reduced 50% after approximately 5 years. Composition of CHLs in the sediment from Hochiminh City canals was comparable to those of common technical mixtures, suggesting continuous input of CHLs to the environment. CHLs might be in use for purposes like termite control, wood preservation, and protection of underground cables. Hazard assessment implies high toxic potential of DDTs for sediments from Hochiminh City canals and suggests the need for better management of municipal discharges.
从胡志明市的运河、西贡-同奈河及其河口采集了表层沉积物样本，这些地方是越南南部胡志明市最主要的工业区之一，用于测定选定的持久性有机污染物（POPs）。污染模式如下：多氯联苯（PCBs）≥滴滴涕（DDTs）＞六氯苯（HCB）＞氯丹（CHLs）＞六氯环己烷（HCHs）。PCBs和DDTs的浓度分别为0.50 - 150纳克/克干重和0.15 - 72纳克/克干重。另一方面，CHLs、HCHs和HCB的浓度大多＜2纳克/克干重。胡志明市运河中所有有机氯（OCs）的含量显著高于其他地区，表明城市地区是水生环境的主要污染源。城市运河中的污染模式是PCBs＞DDTs，但下游和河口地区是PCBs＜DDTs，这表明城市中PCBs的污染尤为严重。对DDTs组成及其比例的研究表明，这种农药持续输入到城市运河中。然而，我们的数据与现有文献的数据相结合表明，环境中PCBs和DDTs呈下降趋势。大约5年后，DDTs浓度降低了50%。胡志明市运河沉积物中CHLs的组成与常见工业混合物的组成相当，这表明CHLs持续输入到环境中。CHLs可能用于白蚁防治、木材防腐和地下电缆保护等用途。风险评估表明，DDTs对胡志明市运河沉积物具有很高的潜在毒性，并表明需要更好地管理城市排放物。
