title: Influence of wastewater type on the impact generated by TiO2nanoparticles on the oxygen uptake rate in activated sludge process.
abstract: Physicochemical characteristics of wastewater have a relationship with the stability of TiO2nanoparticles (NPs). This in turn has an effect on the toxicity of TiO2NPs in microorganisms. In this work, the effect of TiO2NPs on activated sludge process was evaluated using three different types of wastewater: synthetic, raw, and filtered. The results showed that aggregate size of TiO2NPs and their specific adsorption of substrates were influenced by the type of substrates and the presence of suspended solids in the wastewater. It was also shown that TiO2NPs in raw wastewater severely inhibited oxygen uptake by microorganisms as compared to uptake in synthetic or filtered wastewater. The attachment of TiO2NP aggregates on cell membranes was observed for all types of wastewater. However, the internalization of TiO2NPs by microorganisms was observed only for raw and filtered wastewater. These results indicate that the effects caused by TiO2NPs on activated sludge were different depending on the wastewater used for the experiment.
authors.affiliation: Department of Civil and Environmental Engineering, Engineering Division, University of Guanajuato, Av. Juárez 77, Zona Centro, Guanajuato, Gto. 36000, Mexico.
authors.forename: Pabel
authors.initials: P
authors.lastname: Cervantes-Avilés
authors.affiliation: Department of Civil and Environmental Engineering, Engineering Division, University of Guanajuato, Av. Juárez 77, Zona Centro, Guanajuato, Gto. 36000, Mexico.
authors.forename: Nayeli
authors.initials: N
authors.lastname: Camarillo Piñas
authors.affiliation: Department of Science and Engineering for Sustainable Innovation, Faculty of Science and Engineering, Soka University, 1-236, Tangi-machi, Hachioji, Tokyo, 192-8577, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Ida
authors.affiliation: Department of Civil and Environmental Engineering, Engineering Division, University of Guanajuato, Av. Juárez 77, Zona Centro, Guanajuato, Gto. 36000, Mexico. Electronic address: german28@ugto.mx.
authors.forename: Germán
authors.initials: G
authors.lastname: Cuevas-Rodríguez
mesh_terms: D000327:Adsorption; D057919:Biological Oxygen Demand Analysis; D053768:Metal Nanoparticles / Q000737:chemistry; D010100:Oxygen / Q000378:metabolism; D012722:Sewage / Q000737:chemistry / Q000382:microbiology; D014025:Titanium / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D010100:Oxygen; D012722:Sewage; D014025:Titanium; D062065:Wastewater; C009495:titanium dioxide
keywords: Adsorption; Aggregation; Elemental mapping; Nanoecotoxicology; TiO(2) nanoparticles; Wastewater