title: Assessment of pathogenic bacteria in treated graywater and irrigated soils.
abstract: Reuse of graywater (GW) for irrigation is recognized as a sustainable solution for water conservation. One major impediment for reuse of GW is the possible presence of pathogenic microorganisms. The presence and abundance of six pathogens and indicators were investigated in three GW recirculating vertical flow constructed wetland treatment systems and their respective irrigated yard soils. The treated GW and soils were monitored once every two months for six months using real-time quantitative PCR. As a control, samples from four soils irrigated with fresh water (FW) were similarly analyzed for pathogens and indicators. Comparable types of pathogens and fecal indicator bacteria, including Escherichia coli, Klebsiella pneumoniae, Salmonella enterica, Pseudomonas aeruginosa, Enterococcus faecalis, and Shigella spp., were found in the treated GW, their corresponding irrigated soils and the FW-irrigated soils. Moreover, the abundance of these bacteria in the GW- and FW-irrigated soils was of the same order of magnitude, suggesting that the source of the pathogens cannot be established. Our results suggest that GW irrigation has no effect on the diversity and abundance of the tested pathogens and indicators in yard soils.
authors.affiliation: Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben Gurion 84990, Israel.
authors.forename: Maya
authors.initials: M
authors.lastname: Benami
authors.forename: Amit
authors.initials: A
authors.lastname: Gross
authors.forename: Moshe
authors.initials: M
authors.lastname: Herzberg
authors.forename: Ezra
authors.initials: E
authors.lastname: Orlofsky
authors.forename: Ahuva
authors.initials: A
authors.lastname: Vonshak
authors.forename: Osnat
authors.initials: O
authors.lastname: Gillor
mesh_terms: D057914:Agricultural Irrigation / Q000379:methods; D001419:Bacteria / Q000235:genetics* / Q000472:pathogenicity; D044822:Biodiversity; D007557:Israel; D060888:Real-Time Polymerase Chain Reaction; D012988:Soil Microbiology; D013045:Species Specificity; D062065:Wastewater / Q000382:microbiology*
chemical_list: D062065:Wastewater