title: Occurrence and risk assessment of antibiotics in surface water and groundwater from different depths of aquifers: A case study at Jianghan Plain, central China.
abstract: The occurrence of 14 antibiotics (fluoroquinolones, tetracyclines, macrolides and sulfonamides) in groundwater and surface water at Jianghan Plain was investigated during three seasons. The total concentrations of target compounds in the water samples were higher in spring than those in summer and winter. Erythromycin was the predominant antibiotic in surface water samples with an average value of 1.60μg/L, 0.772μg/L and 0.546μg/L respectively in spring, summer and winter. In groundwater samples, fluoroquinolones and tetracyclines accounted for the dominant proportion of total antibiotic residues. The vertical distributions of total antibiotics in groundwater samples from three different depths boreholes (10m, 25m, and 50m) exhibited irregular fluctuations. Consistently decreasing of antibiotic residues with increasing of depth was observed in four (G01, G02, G03 and G05) groundwater sampling sites over three seasons. However, at the sampling sites G07 and G08, the pronounced high concentrations of total antibiotic residues were detected in water samples from 50m deep boreholes instead of those at upper aquifer in winter sampling campaign, with the total concentrations of 0.201μg/L and 0.100μg/L respectively. The environmental risks posed by the 14 antibiotics were assessed by using the methods of risk quotient and mixture risk quotient for algae, daphnids and fish in surface water and groundwater. The results suggested that algae might be the aquatic organism most sensitive to the antibiotics, with the highest risk levels posed by erythromycin in surface water and by ciprofloxacin in groundwater among the 14 antibiotics. In addition, the comparison between detected antibiotics in groundwater samples and the reported effective concentrations of antibiotics on denitrification by denitrifying bacteria, indicating this biogeochemical process driven by microorganisms won't be inhibitory influenced by the antibiotic residues in groundwater.
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Yao
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China. Electronic address: yx.wang@cug.edu.cn.
authors.forename: Yanxin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Tong
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Yamin
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Hubei Provincial Center for Disease Control & Prevention, Wuhan 430074, China.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Gan
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Chuangju
authors.initials: C
authors.lastname: Dong
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Duan
authors.affiliation: School of Environmental Studies, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Zhao
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002681:China; D004784:Environmental Monitoring; D024841:Fluoroquinolones / Q000032:analysis; D005618:Fresh Water / Q000737:chemistry*; D060587:Groundwater / Q000737:chemistry*; D018942:Macrolides / Q000032:analysis; D018570:Risk Assessment; D012621:Seasons; D013449:Sulfonamides / Q000032:analysis; D013754:Tetracyclines / Q000032:analysis; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D018942:Macrolides; D013449:Sulfonamides; D013754:Tetracyclines; D014874:Water Pollutants, Chemical; D014867:Water
keywords: Antibiotics; Groundwater; Occurrence; Risk assessment; Surface water