Quantitative PCR monitoring of antibiotic resistance genes and bacterial pathogens in three European artificial groundwater recharge systems

Appl Environ Microbiol. 2009 Jan;75(1):154-63. doi: 10.1128/AEM.01649-08. Epub 2008 Nov 14.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Belgium
  • Colony Count, Microbial
  • DNA, Bacterial / genetics
  • Disinfection / methods
  • Drug Resistance, Bacterial*
  • Halogenation
  • Helicobacter pylori / genetics
  • Helicobacter pylori / isolation & purification*
  • Italy
  • Mycobacterium avium / genetics
  • Mycobacterium avium / isolation & purification*
  • Polymerase Chain Reaction / methods*
  • Spain
  • Ultrafiltration
  • Ultraviolet Rays
  • Water Microbiology*
  • Water Purification
  • Yersinia enterocolitica / genetics
  • Yersinia enterocolitica / isolation & purification*

Substances

  • Bacterial Proteins
  • DNA, Bacterial