Pollution sources and occurrences of selected persistent organic pollutants (POPs) in sediments of the Mekong River delta, South Vietnam.
نویسندگان
چکیده
The Mekong River delta is one of the largest agricultural land in the Southeast Asia. It plays a very important role for agriculture and fisheries in South Vietnam. However, comprehensive studies on the environmental pollution of persistent organic pollutants (POPs) in Mekong River delta have not been carried out in recent years. In this study, we collected sediment samples from the Mekong River to evaluate the contamination and ecological risks caused by several POPs. The contamination pattern of POPs was DDT>PCBs>CHLs>HCHs>HCB. DDTs are the most abundant pollutants, their concentration ranging from 0.01 to 110 ng/g dry wt, followed by PCBs (0.039-9.2 ng/g dry wt). DDTs and PCBs concentrations were higher in sediment from adjacent to urban areas than those from rural and agricultural sites, suggesting urban areas as important point sources of DDTs and PCBs to the river. Ratio of p,p'-DDT/p,p'-DDE was lower compared to those previously reported. However, some samples still had the ratio higher than 0.5, indicating recent input of DDT into the aquatic environments. This result shows that although the magnitude of contamination decreased over time, recent inputs of DDTs to the river still occur. Some sediment samples had concentrations of DDT compounds higher than the standards from the Canadian Environmental Quality Guideline, suggesting continuous monitoring for POPs contamination in the Mekong River is necessary.
منابع مشابه
Characterization of transboundary POP contamination in aquatic ecosystems of Pearl River delta.
During the past two decades, the rapid development of the Pearl River delta leads to substantial accumulation of various toxic organic compounds. This study aims to give a preliminary characterization of the existing state of contamination in this region and to provide insight into the possible fate of persistent organic pollutants (POPs) in this estuary. The available data on POPs in water, ri...
متن کاملAssessing Heavy Metals Pollution of the Mangrove Sediments along Tidal Flat of the Mehran River Delta, Persian Gulf
The relationship between the concentration of heavy metals and physicochemical factors was studied in the fine-grained sediments of the tidal section of the Mehran delta where mangrove trees have grown. Surface sediments of the tidal zone of the Mehran delta were sampled. The grain size distribution, calcium carbonate, organic matter contents, pH/Eh, and heavy metals concentration were determin...
متن کاملMagnitude of arsenic pollution in the Mekong and Red River Deltas--Cambodia and Vietnam.
Large alluvial deltas of the Mekong River in southern Vietnam and Cambodia and the Red River in northern Vietnam have groundwaters that are exploited for drinking water by private tube-wells, which are of increasing demand since the mid-1990s. This paper presents an overview of groundwater arsenic pollution in the Mekong delta: arsenic concentrations ranged from 1-1610 microg/L in Cambodia (ave...
متن کاملShort communication: Morphometric, growth and condition factor variations of Boleophthalmus boddarti in the Mekong delta, Vietnam
متن کامل
Persistent organic pollutants in sediments from Sai Gon-Dong Nai River basin, Vietnam: levels and temporal trends.
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/...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemosphere
دوره 67 9 شماره
صفحات -
تاریخ انتشار 2007