Preliminary assessment of the interaction of introduced biological agents with biofilms in water distribution systems.

Sinclair, Michael B. ; Caldwell, Sara ; Jones, Howland D. T. ; Altman, Susan Jeanne ; Souza, Caroline Ann ; McGrath, Lucas K.

Sandia National Laboratories

关键词: Pseudomonas;    Drinking Water-Contamination.;    Inoculation;    Testing;    Biofilms.;   

DOI  :  10.2172/876521
RP-ID  :  SAND2005-7897
RP-ID  :  AC04-94AL85000
RP-ID  :  876521

美国|英语

来源: UNT Digital Library

【 摘 要 】

Basic research is needed to better understand the potential risk of dangerous biological agents that are unintentionally or intentionally introduced into a water distribution system. We report on our capabilities to conduct such studies and our preliminary investigations. In 2004, the Biofilms Laboratory was initiated for the purpose of conducting applied research related to biofilms with a focus on application, application testing and system-scale research. Capabilities within the laboratory are the ability to grow biofilms formed from known bacteria or biofilms from drinking water. Biofilms can be grown quickly in drip-flow reactors or under conditions more analogous to drinking-water distribution systems in annular reactors. Biofilms can be assessed through standard microbiological techniques (i .e, aerobic plate counts) or with various visualization techniques including epifluorescent and confocal laser scanning microscopy and confocal fluorescence hyperspectral imaging with multivariate analysis. We have demonstrated the ability to grow reproducible Pseudomonas fluorescens biofilms in the annular reactor with plate counts on the order of 10{sup 5} and 10{sup 6} CFU/cm{sup 2}. Stationary phase growth is typically reached 5 to 10 days after inoculation. We have also conducted a series of pathogen-introduction experiments, where we have observed that both polystyrene microspheres and Bacillus cereus (as a surrogate for B. anthracis) stay incorporated in the biofilms for the duration of our experiments, which lasted as long as 36 days. These results indicated that biofilms may act as a safe harbor for bio-pathogens in drinking water systems, making it difficult to decontaminate the systems.