title: Occurrence, spatiotemporal distribution, mass balance and ecological risks of antibiotics in subtropical shallow Lake Taihu, China.
abstract: The objective of this study was to evaluate the occurrence, spatiotemporal distribution, mass balance and ecological risks of 43 commonly used human and veterinary antibiotics in both aqueous and sedimentary phases in a large subtropical shallow lake, Lake Taihu. In the aqueous phase, sulfonamides (2.64-344 ng L(-1)), lincomycin (ND to 53.8 ng L(-1)) and florfenicol (0.15-963 ng L(-1)) were the main compounds with high concentrations and detection frequencies. In the sedimentary phase, fluoroquinolones (ND to 174 ng g(-1), dry weight) and tetracyclines (ND to 39.6 ng g(-1), dry weight) were the predominant compounds. Antibiotic concentrations in Lake Taihu were generally lower relative to data documented in previous studies on China and other countries. The composition of antibiotics showed that livestock wastewater might be the main source of antibiotics in Lake Taihu, followed by domestic wastewater. Antibiotics in the lake water showed slight spatial variation in summer and significant spatial variation in winter; whereas, antibiotic concentrations in the sediments varied obviously, with high concentrations found in the sites close to potential pollution sources. Mass balance showed that sediments are an important sink and potential source for fluoroquinolones and tetracyclines. In addition to antibiotics' physicochemical properties, the spatiotemporal distribution of antibiotics in the lake was influenced by both pollution sources and lake hydrodynamics. The environmental risk assessment results showed that sulfamethoxazole could pose high risks on the algae in the aquatic ecosystem, followed by tetracyclines (algae) and fluoroquinolones (bacteria). Overall, our study reveals complex compositions and clear spatiotemporal dynamics in Lake Taihu, which were the consequence of pollution sources and lake hydrodynamics.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China. qlwu@niglas.ac.cn ljzhou@niglas.ac.cn.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhou
authors.forename: Qinglong L
authors.initials: QL
authors.lastname: Wu
authors.forename: Bei-Bei
authors.initials: BB
authors.lastname: Zhang
authors.forename: Yong-Gang
authors.initials: YG
authors.lastname: Zhao
authors.forename: Bi-Ying
authors.initials: BY
authors.lastname: Zhao
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D006801:Humans; D060106:Lakes / Q000737:chemistry*; D018570:Risk Assessment; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical