title: Removal of MS2, Qβ and GA bacteriophages during drinking water treatment at pilot scale.
abstract: The removal of MS2, Qβ and GA, F-specific RNA bacteriophages, potential surrogates for pathogenic waterborne viruses, was investigated during a conventional drinking water treatment at pilot scale by using river water, artificially and independently spiked with these bacteriophages. The objective of this work is to develop a standard system for assessing the effectiveness of drinking water plants with respect to the removal of MS2, Qβ and GA bacteriophages by a conventional pre-treatment process (coagulation-flocculation-settling-sand filtration) followed or not by an ultrafiltration (UF) membrane (complete treatment process). The specific performances of three UF membranes alone were assessed by using (i) pre-treated water and (ii) 0.1 mM sterile phosphate buffer solution (PBS), spiked with bacteriophages. These UF membranes tested in this work were designed for drinking water treatment market and were also selected for research purpose. The hypothesis serving as base for this study was that the interfacial properties for these three bacteriophages, in terms of electrostatic charge and the degree of hydrophobicity, could induce variations in the removal performances achieved by drinking water treatments. The comparison of the results showed a similar behaviour for both MS2 and Qβ surrogates whereas it was particularly atypical for the GA surrogate. The infectious character of MS2 and Qβ bacteriophages was mostly removed after clarification followed by sand filtration processes (more than a 4.8-log reduction) while genomic copies were removed at more than a 4.0-log after the complete treatment process. On the contrary, GA bacteriophage was only slightly removed by clarification followed by sand filtration, with less than 1.7-log and 1.2-log reduction, respectively. After the complete treatment process achieved, GA bacteriophage was removed with less than 2.2-log and 1.6-log reduction, respectively. The effectiveness of the three UF membranes tested in terms of bacteriophages removal showed significant differences, especially for GA bacteriophage. These results could provide recommendations for drinking water suppliers in terms of selection criteria for membranes. MS2 bacteriophage is widely used as a surrogate for pathogenic waterborne viruses in Europe and the United States. In this study, the choice of MS2 bacteriophage as the best surrogate to be used for assessment of the effectiveness of drinking water treatment in removal of pathogenic waterborne viruses in worst conditions is clearly challenged. It was shown that GA bacteriophage is potentially a better surrogate as a worst case than MS2. Considering GA bacteriophage as the best surrogate in this study, a chlorine disinfection step could guaranteed a complete removal of this model and ensure the safety character of drinking water plants.
authors.affiliation: Veolia Environment Research and Innovation, Chemin de la Digue, BP76, 78608 Maisons-Laffitte Cedex, France. nicolas.boudaud@veolia.com
authors.forename: Nicolas
authors.initials: N
authors.lastname: Boudaud
authors.forename: Claire
authors.initials: C
authors.lastname: Machinal
authors.forename: Fabienne
authors.initials: F
authors.lastname: David
authors.forename: Armelle
authors.initials: A
authors.lastname: Fréval-Le Bourdonnec
authors.forename: Jérôme
authors.initials: J
authors.lastname: Jossent
authors.forename: Fanny
authors.initials: F
authors.lastname: Bakanga
authors.forename: Charlotte
authors.initials: C
authors.lastname: Arnal
authors.forename: Marie Pierre
authors.initials: MP
authors.lastname: Jaffrezic
authors.forename: Sandrine
authors.initials: S
authors.lastname: Oberti
authors.forename: Christophe
authors.initials: C
authors.lastname: Gantzer
mesh_terms: D001435:Bacteriophages / Q000302:isolation & purification*; D002713:Chlorine / Q000302:isolation & purification; D060766:Drinking Water / Q000821:virology*; D005602:France; D017909:Levivirus / Q000302:isolation & purification*; D008567:Membranes, Artificial; D010865:Pilot Projects; D045483:Rivers / Q000737:chemistry; D012996:Solutions; D014462:Ultrafiltration; D038301:Virus Inactivation; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*; D060753:Water Quality
chemical_list: D060766:Drinking Water; D008567:Membranes, Artificial; D012996:Solutions; D002713:Chlorine