Effect of Disinfectant, Water Age, and Pipe Materials on Bacterial and Eukaryotic Community Structure in Drinking Water Biofilm

Abstract

Availability of safe, pathogen-free drinking water is vital to public health; however, it is impossible to deliver sterile drinking water to consumers. Recent microbiome research is bringing new understanding to the true extent and diversity of microbes that inhabit water distribution systems. The purpose of this study was to determine how water chemistry in main distribution lines shape the microbiome in drinking water biofilms and to explore potential associations between opportunistic pathogens and indigenous drinking water microbes. Effects of disinfectant (chloramines, chlorine), water age (2.3 days, 5.7 days), and pipe material (cement, iron, PVC) were compared in parallel triplicate simulated water distribution systems. Pyrosequencing was employed to characterize bacteria and terminal restriction fragment polymorphism was used to profile both bacteria and eukaryotes inhabiting pipe biofilms. Disinfectant and water age were both observed to be strong factors in shaping bacterial and eukaryotic community structures. Pipe material only influenced the bacterial community structure (ANOSIM test, P < 0.05). Interactive effects of disinfectant, pipe material, and water age on both bacteria and eukaryotes were noted. Disinfectant concentration had the strongest effect on bacteria, while dissolved oxygen appeared to be a major driver for eukaryotes (BEST test). Several correlations of similarity metrics among populations of bacteria, eukaryotes, and opportunistic pathogens, as well as one significant association between mycobacterial and proteobacterial operational taxonomic units, provides insight into means by which manipulating the microbiome may lead to new avenues for limiting the growth of opportunistic pathogens (e.g., Legionella) or other nuisance organisms (e.g., nitrifiers).

The application of impedance measurement to assess biofilm development on technical materials used for water supply system construction

“…The study confirmed the results of Wang demonstrating that the material from which the water supply network is made of can have a significant effect on the amount, frequency and type of biofilm formation, the presence of pathogens as well as the effectiveness of used disinfectants [18].…”

The Antibiotic Resistance by Bacteria Forming Biofilm into Water Pipes

“…It has been reported that the formation of bacterial biofilm contributes significantly to antibiotic resistance (Stewart and Costerton, 2001). The drinking water must be free of pathogenic infectious agents, however it has been observed that it has a variety of microorganisms, including bacteria forming biofilm in distribution systems (Wang et al, 2014).…”

“…The factors that contribute significantly to the development of them are: ineffective concentration of disinfectants, pH and water temperature, residence time of the water in the tanks and piping, tube construction material. So the drinking water loses quality along its passage through the water supply pipes (Wang et al, 2014). The presence of bacteria in water pipes indicates the poor quality of water and water is a vehicle for diffusion of pathogenic bacteria (Chaves-Simões and Simões, 2013).…”

Microbiome profiling of drinking water in relation to incidence of inflammatory bowel disease

“…Proteobacteria as a principal phylum in drinking water is 216 well documented in the literature (Lautenschlager et al 2014;Wang et al 2014;Liu et al 2014;Lührig 217 et al 2015). The average relative abundance of Proteobacteria was 92%.…”