title: Distribution of antibiotic resistance in urban watershed in Japan.
abstract: Antibiotic-resistant E. coli concentrations showed large spatial and temporal variations, with greater concentrations observed in tributaries and downstream than in the upstream and midstream. Twenty percent of the geometric mean concentrations of antibiotic-resistant E. coli in the Tama River basin (Japan) exceeded the maximum acceptable concentration of indicator E. coli established by the USEPA. The indicator E. coli concentrations were positively correlated with those of antibiotic-resistant E. coli and multiple-antibiotic-resistant E. coli (resistance to more than two kinds of antibiotics), respectively, but not the detection rate of antibiotic-resistant E. coli, implying that use of antibiotic-resistant E. coli concentration rather than the detection rate can be a better approach for water quality assessment. Multiple-antibiotic-resistant E. coli is a useful indicator for estimating the resistance diffusion, water quality degradation and public health risk potential. This assessment provides beneficial information for setting national regulatory or environmental standards and managing integrated watershed areas.
authors.affiliation: Faculty of Environmental and Information Studies, Tokyo City University, Tsuzuki-ku, Yokohama, Japan. yhamu@tcu.ac.jp
authors.forename: Young-Sik
authors.initials: YS
authors.lastname: Ham
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kobori
authors.forename: Joo-Hyon
authors.initials: JH
authors.lastname: Kang
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Michiyo
authors.initials: M
authors.lastname: Iino
authors.forename: Hayashi
authors.initials: H
authors.lastname: Nomura
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification*; D007564:Japan; D045483:Rivers / Q000737:chemistry / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000494:pharmacology; D060753:Water Quality
chemical_list: D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical