title: Photodegradation of the antineoplastic cyclophosphamide: a comparative study of the efficiencies of UV/H2O2, UV/Fe2+/H2O2 and UV/TiO2 processes.
abstract: Anticancer drugs are harmful substances that can have carcinogenic, mutagenic, teratogenic, genotoxic, and cytotoxic effects even at low concentrations. More than 50 years after its introduction, the alkylating agent cyclophosphamide (CP) is still one of the most consumed anticancer drug worldwide. CP has been detected in water bodies in several studies and is known as being persistent in the aquatic environment. As the traditional water and wastewater treatment technologies are not able to remove CP from the water, different treatment options such as advanced oxidation processes (AOPs) are under discussion to eliminate these compounds. The present study investigated the degradation of CP by three different AOPs: UV/H2O2, UV/Fe(2+)/H2O2 and UV/TiO2. The light source was a Hg medium-pressure lamp. Prescreening tests were carried out and afterwards experiments based on the optimized conditions were performed. The primary elimination of the parent compounds and the detection of transformation products (TPs) were monitored with LC-UV-MS/MS analysis, whereas the degree of mineralization was monitored by measuring the dissolved organic carbon (DOC). Ecotoxicological assays were carried out with the luminescent bacteria Vibrio fischeri. CP was completely degraded in all treatments and UV/Fe(2+)/H2O2 was the fastest process, followed by UV/H2O2 and UV/TiO2. All the reactions obeyed pseudo-first order kinetics. Considering the mineralization UV/Fe(2+)/H2O2 and UV/TiO2 were the most efficient process with mineralization degrees higher than 85%, whereas UV/H2O2 achieved 72.5% of DOC removal. Five transformation products were formed during the reactions and identified. None of them showed significant toxicity against V. fischeri.
authors.affiliation: Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany; Graduate Program in Environmental Technology, Universidade de Santa Cruz do Sul - UNISC, Av. Independência, 2293, CEP 96815-900 Santa Cruz do Sul, Rio Grande do Sul, Brazil. Electronic address: lutterbeck@leuphana.de.
authors.forename: Carlos Alexandre
authors.initials: CA
authors.lastname: Lutterbeck
authors.affiliation: Graduate Program in Environmental Technology, Universidade de Santa Cruz do Sul - UNISC, Av. Independência, 2293, CEP 96815-900 Santa Cruz do Sul, Rio Grande do Sul, Brazil. Electronic address: enio@unisc.br.
authors.forename: Ênio Leandro
authors.initials: ÊL
authors.lastname: Machado
authors.affiliation: Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany. Electronic address: klaus.kuemmerer@uni.leuphana.de.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kümmerer
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects / Q000378:metabolism; D018906:Antineoplastic Agents, Alkylating / Q000737:chemistry*; D003520:Cyclophosphamide / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry / Q000528:radiation effects; D007501:Iron / Q000737:chemistry / Q000528:radiation effects; D007700:Kinetics; D010084:Oxidation-Reduction; D010782:Photolysis; D053719:Tandem Mass Spectrometry; D014025:Titanium / Q000737:chemistry / Q000528:radiation effects; D014466:Ultraviolet Rays; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003520:Cyclophosphamide; D006861:Hydrogen Peroxide; D007501:Iron; D014025:Titanium; D062065:Wastewater; D014874:Water Pollutants, Chemical; C009495:titanium dioxide
keywords: Advanced oxidation; Cyclophosphamide; Degradation; Ecotoxicity; Mineralization; Transformation products