Survival of infectious prions in water.

The objective of this study was to evaluate the fate of infectious prions in water. Known concentrations of infectious prions were added to deionized water, tap water, and wastewater. Samples were incubated at 25°C, 37°C, and 50°C for 1 to 8 weeks.

Survival of infectious prions in Class B biosolids.

This study developed a method for extracting infectious prions from Class B biosolids and subsequently evaluated the survival of infectious prions under the influence of mesophilic (37°C) and thermophilic (60°C) temperatures in Class B biosolids. Unlike other studies, this study utilized a scrapie cell assay to determine infectivity and quantity of infectious prions. The best method for extraction was exposing the biosolids to 4 M urea at 80°C for 10 minutes followed by a membrane centrifugation to reduce the concentration of urea.

Evaluation of select sensors for real-time monitoring of Escherichia coli in water distribution systems.

This study evaluated real-time sensing of Escherichia coli as a microbial contaminant in water distribution systems. Most sensors responded to increased E. coli concentrations, showing that select sensors can detect microbial water quality changes and be utilized as part of a contaminant warning system.

Point-of-Use drinking water devices for assessing microbial contamination in finished water and distribution systems.

The objective of this study was to develop a method to monitor the microbial quality of treated drinking water at the tap utilizing point-of-use filter systems that are placed in water vending machines. Such vending machines have high-volume water throughput and allow for an evaluation of the occurrence of human enteric pathogens and fecal indicator bacteria in tap water over extended time periods. Seeded experiments, using Escherichia coli and bacteriophage MS-2, were performed on (i) new filters, (ii) artificially aged filters, and (iii) filters that had been used in the field (naturally aged filters) to evaluate the efficiency of recovery of these organisms from the three-component filter set (30 microm, 5 mirom, solid block carbon (SBC)) by evaluating each filter independently.