title: Photodegradation kinetics and transformation products of ketoprofen, diclofenac and atenolol in pure water and treated wastewater.
abstract: Pharmaceutical compounds such as ketoprofen, diclofenac and atenolol are frequently detected at relatively high concentrations in secondary effluents from wastewater treatment plants. Therefore, it is important to assess their transformation kinetics and intermediates in subsequent disinfection processes, such as direct ultraviolet (UV) irradiation. The photodegradation kinetics of these compounds using a medium pressure (MP) lamp was assessed in pure water, as well as in filtered and unfiltered treated wastewater. Ketoprofen had the highest time- and fluence-based rate constants in all experiments, whereas atenolol had the lowest values, which is consistent with the corresponding decadic molar absorption coefficient and quantum yield. The fluence-based rate constants of all compounds were evaluated in filtered and unfiltered wastewater matrices as well as in pure water. Furthermore, transformation products of ketoprofen, diclofenac and atenolol were identified and monitored throughout the irradiation experiments, and photodegradation pathways were proposed for each compound. This enabled the identification of persistent transformation products, which are potentially discharged from WWTP disinfection works employing UV photolysis.
authors.affiliation: REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: R
authors.initials: R
authors.lastname: Salgado
authors.forename: V J
authors.initials: VJ
authors.lastname: Pereira
authors.forename: G
authors.initials: G
authors.lastname: Carvalho
authors.forename: R
authors.initials: R
authors.lastname: Soeiro
authors.forename: V
authors.initials: V
authors.lastname: Gaffney
authors.forename: C
authors.initials: C
authors.lastname: Almeida
authors.forename: V
authors.initials: V
authors.lastname: Vale Cardoso
authors.forename: E
authors.initials: E
authors.lastname: Ferreira
authors.forename: M J
authors.initials: MJ
authors.lastname: Benoliel
authors.forename: T A
authors.initials: TA
authors.lastname: Ternes
authors.forename: A
authors.initials: A
authors.lastname: Oehmen
authors.forename: M A M
authors.initials: MA
authors.lastname: Reis
authors.forename: J P
authors.initials: JP
authors.lastname: Noronha
mesh_terms: D001262:Atenolol / Q000528:radiation effects*; D004008:Diclofenac / Q000528:radiation effects*; D007660:Ketoprofen / Q000528:radiation effects*; D007700:Kinetics; D010782:Photolysis; D011312:Pressure; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000528:radiation effects*; D018508:Water Purification / Q000379:methods
chemical_list: D001262:Atenolol; D004008:Diclofenac; D007660:Ketoprofen; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical