Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/2563
Title: Transport and adsorption of antibiotics by marine sediments in a dynamic environment
Authors: Xu, Wei-hai
Zhang, Gan
Wai, Wing-hong Onyx
Zou, Shi-chun
Li, Xiangdong
Subjects: Adsorption
Antibiotics
Dynamic water environment
Persistence
Sediments
Hong Kong, South China
Transport
Issue Date: Aug-2009
Publisher: Springer-Verlag
Source: Journal of soil and sediment, Aug. 2009, v. 9, no. 4, p. 364-373.
Abstract: Background, aim, and scope: Bed sediments are the major sink for many contaminants in aquatic environments. With increasing knowledge of and research on the environmental occurrence of antibiotics, there has been growing interest in their behaviour and fate in aquatic environments. However, there is little information about the behaviour of antibiotics in a dynamic water/sediment environment, such as river and coastal marine water. Therefore, the aims of the present study were: (1) to study the transport and distribution of four common antibiotics between water and sediment in both dynamic and quiescent water/sediment systems and (2) to understand the persistence and possible degradation of the four antibiotics in the two different systems.
Materials and methods: A lid-driven elongated annular flume, designed to reduce the centrifugal effect, was used to simulate a dynamic water environment. In addition, a quiescent water/sediment experiment was conducted for comparison with the dynamic water system. The seawater and sediment, used in both experiments of flowing and quiescent water/sediment systems, were collected from Victoria Harbour, a dynamic coastal environment in an urban setting. The four antibiotics selected in this study were ofloxacin (OFL), roxithromycin (RTM), erythromycin (ETM), and sulfamethoxazole (SMZ), the most commonly used antibiotics in South China.
Results and discussion: Antibiotics in an overlying solution decreased very quickly in the flume system due to the sorption to suspended particles and surface sediment. There were significant differences in the adsorption of the four antibiotics in sediment. OFL showed a high tendency to be adsorbed by sediment with a high K[sub d] value (2980 L/Kg), while the low K[sub d] values of SMZ indicated that there was a large quantity in water. The four antibiotics reached a depth of 20–30 mm in the sediment over a period of 60 days in the flume system. However, the compounds were only found in surface sediment (above 10 mm) in the quiescent system, indicating the influence of the dynamic flume system on the distribution of antibiotics in sediment. OFL showed a moderate persistence in the dynamic flume system, while other three antibiotics had less persistence in sediment. However, all of the four compounds showed moderate persistence in the quiescent system.
Recommendations and perspectives: The study showed the rapid diffusive transfer of antibiotics from water to sediment in the dynamic flume system. The four antibiotics exhibited larger differences in their adsorption to sediment in both dynamic and quiescent systems due to their different K[sub d] values. The high sorption of antibiotics to marine sediment may reduce their availability to benthic invertebrates.
Rights: © Springer-Verlag 2009. The original publication is available at http://www.springerlink.com.
Type: Journal/Magazine Article
URI: http://hdl.handle.net/10397/2563
DOI: 10.1007/s11368-009-0091-z
Appears in Collections:CEE Journal/Magazine Articles

Files in This Item:
File Description SizeFormat 
B72 Flume Paper JSS 2009.pdfPre-published version342.99 kBAdobe PDFView/Open


All items in the PolyU Institutional Repository are protected by copyright, with all rights reserved, unless otherwise indicated. No item in the PolyU IR may be reproduced for commercial or resale purposes.