title: Combination of nanofiltration and ozonation for the remediation of real municipal wastewater effluents: Acute and chronic toxicity assessment.
abstract: The purpose of this work was to study the ozonation of nanofiltration (NF) retentates of real municipal wastewater treatment plant (MWTP) effluents for removal of microcontaminants (MCs) and toxicity. MCs present in these effluents were monitored using LC-MS/MS. Acute and chronic toxicity was addressed with Daphnia magna, Vibrio fischeri and Selenastrum capricornutum. Up to 40 MCs were found, most of them in concentrations over 100ng/L. 90% degradation of the sum of MCs was the critical point of comparison. When the NF membrane system was applied to MWTP effluents, treatment of NF rejection needed 2.75-4.5g O3/m3,4.5g O3/m3, which is less than 50% of the ozone needed for direct treatment of MWTP effluent. Treatment time (lower than 11min) was not influenced by MCs concentration, at least in the range tested (25-190μg/L). It has been demonstrated that consumption of ozone increased with organic load and inorganic content of different real effluents. MCs were eliminated by ozonation but acute toxicity (against V. fischeri and D. magna) increased. Chronic toxicity results were different and contrary in D. magna and S. capricornutum, due to the generation of new transformation products more toxic to D. magna than the parent contaminants. S. capricornutum inhibition percentage decreased in all cases after ozonation treatment. According to these results, before ozonation is implemented in MWTPs for the removal of MCs, the transformation products must first be examined and the treatment time or ozone doses should be extended to complete degradation if necessary.
authors.affiliation: Laboratorio de Investigaciones Medioambientales en Zonas Áridas, LIMZA. EUDIM, University of Tarapacá, Avda. General Velásquez 1775, Arica, Chile.
authors.forename: S
authors.initials: S
authors.lastname: Miralles-Cuevas
authors.affiliation: Plataforma Solar de Almería-CIEMAT, Ctra Senés km 4, 04200 Tabernas Almería, Spain; CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Oller
authors.affiliation: CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Agüera
authors.affiliation: Catalan Institute for Water Research (ICRA), Girona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Llorca
authors.affiliation: CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Sánchez Pérez
authors.affiliation: Plataforma Solar de Almería-CIEMAT, Ctra Senés km 4, 04200 Tabernas Almería, Spain; CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain. Electronic address: Sixto.malato@psa.es.
authors.forename: S
authors.initials: S
authors.lastname: Malato
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects; D000818:Animals; D000460:Chlorophyta / Q000187:drug effects; D003621:Daphnia / Q000187:drug effects; D052918:Environmental Restoration and Remediation / Q000379:methods*; D008567:Membranes, Artificial; D010126:Ozone / Q000737:chemistry*; D014462:Ultrafiltration / Q000379:methods*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000633:toxicity*; D018508:Water Purification
chemical_list: D008567:Membranes, Artificial; D010126:Ozone; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Acute/chronic toxicity; Mass spectrometry; Nanofiltration; Ozonation