title: Continuous ozonation treatment of ofloxacin: transformation products, water matrix effect and aquatic toxicity.
abstract: The continuous ozonation of the antibiotic ofloxacin (OFX) has been performed using a synthetic water matrix and in a sewage treatment plant (STP) effluent. The aim was to study the effect of the water matrix on the ozonation with particular emphasis on the aquatic toxicity of treated water. OFX was completely removed in both water matrices, although the amount of ozone consumed for its depletion was strongly matrix-dependent. The extent of mineralization was limited and a number of intermediate transformation products (TPs) appeared, twelve of which could be identified. OFX reaction pathway includes the degradation of piperazinyl and quinolone moieties. The further oxidation of TPs gave rise to the formation and accumulation of carboxylic acids, aldehydes, nitrogen-containing organic compounds and inorganic ions. Aquatic toxicity of treated mixtures was assessed using four standard species: the bacteria Vibrio fischeri and Pseudomonas putida as target organisms and the algae Pseudokirchneriella subcapitata and the protozoan Tetrahymena thermophila as non-target organisms. OFX was toxic for the bacteria and the microalgae at the spiked concentration in untreated water. However, the continuous ozonation at the upper operational limit removed its toxic effects. T. thermophila was not affected by OFX, but was sensitive to STP effluent.
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain.
authors: Jose B
authors: JB
authors: Carbajo
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain; Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain.
authors: Alice L
authors: AL
authors: Petre
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain; Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain.
authors: Roberto
authors: R
authors: Rosal
authors: Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain; Department of Chemistry and Physics, University of Almería, E-04120 Almería, Spain.
authors: Sonia
authors: S
authors: Herrera
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain; Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain.
authors: Pedro
authors: P
authors: Letón
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain; Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain.
authors: Eloy
authors: E
authors: García-Calvo
authors: Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain; Department of Chemistry and Physics, University of Almería, E-04120 Almería, Spain.
authors: Amadeo R
authors: AR
authors: Fernández-Alba
authors: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Spain; Advanced Study Institute of Madrid, IMDEA-Agua, Parque Científico Tecnológico, E-28805 Alcalá de Henares, Spain. Electronic address: ja.perdigon@uah.es.
authors: Jose A
authors: JA
authors: Perdigón-Melón
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D015242:Ofloxacin / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical; D010126:Ozone; D015242:Ofloxacin
keywords: Biotest battery; Continuous ozonation; Quinolone antibiotic; Reaction pathway; STP effluent