title: Quantitative PCR monitoring of antibiotic resistance genes and bacterial pathogens in three European artificial groundwater recharge systems.
abstract: Aquifer recharge presents advantages for integrated water management in the anthropic cycle, namely, advanced treatment of reclaimed water and additional dilution of pollutants due to mixing with natural groundwater. Nevertheless, this practice represents a health and environmental hazard because of the presence of pathogenic microorganisms and chemical contaminants. To assess the quality of water extracted from recharged aquifers, the groundwater recharge systems in Torreele, Belgium, Sabadell, Spain, and Nardò, Italy, were investigated for fecal-contamination indicators, bacterial pathogens, and antibiotic resistance genes over the period of 1 year. Real-time quantitative PCR assays for Helicobacter pylori, Yersinia enterocolitica, and Mycobacterium avium subsp. paratuberculosis, human pathogens with long-time survival capacity in water, and for the resistance genes ermB, mecA, blaSHV-5, ampC, tetO, and vanA were adapted or developed for water samples differing in pollutant content. The resistance genes and pathogen concentrations were determined at five or six sampling points for each recharge system. In drinking and irrigation water, none of the pathogens were detected. tetO and ermB were found frequently in reclaimed water from Sabadell and Nardò. mecA was detected only once in reclaimed water from Sabadell. The three aquifer recharge systems demonstrated different capacities for removal of fecal contaminators and antibiotic resistance genes. Ultrafiltration and reverse osmosis in the Torreele plant proved to be very efficient barriers for the elimination of both contaminant types, whereas aquifer passage followed by UV treatment and chlorination at Sabadell and the fractured and permeable aquifer at Nardò posed only partial barriers for bacterial contaminants.
authors.affiliation: Department of Environmental Microbiology, Technical University Berlin, Franklinstr. 29, D-10587 Berlin, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Böckelmann
authors.forename: Hans-Henno
authors.initials: HH
authors.lastname: Dörries
authors.forename: M Neus
authors.initials: MN
authors.lastname: Ayuso-Gabella
authors.forename: Miquel
authors.initials: M
authors.lastname: Salgot de Marçay
authors.forename: Valter
authors.initials: V
authors.lastname: Tandoi
authors.forename: Caterina
authors.initials: C
authors.lastname: Levantesi
authors.forename: Costantino
authors.initials: C
authors.lastname: Masciopinto
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Van Houtte
authors.forename: Ulrich
authors.initials: U
authors.lastname: Szewzyk
authors.forename: Thomas
authors.initials: T
authors.lastname: Wintgens
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Grohmann
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001530:Belgium; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000235:genetics; D004203:Disinfection / Q000379:methods; D024881:Drug Resistance, Bacterial; D054879:Halogenation; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification*; D007558:Italy; D009162:Mycobacterium avium / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods*; D013030:Spain; D014462:Ultrafiltration; D014466:Ultraviolet Rays; D014871:Water Microbiology; D018508:Water Purification; D015008:Yersinia enterocolitica / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial