Persistent Link:
http://hdl.handle.net/10150/194069
Title:
Novel Strategies for the Detection of Pathogens in Drinking Water
Author:
Miles, Syreeta
Issue Date:
2010
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
To protect public health, detection methods have been developed to monitor drinking water for pathogens. The goal of this dissertation is to evaluate and utilize novel methods that enhances detection and further reduces the risk of waterborne pathogens. The study in Appendix A developed a method to monitor the microbial quality of treated drinking water at the tap utilizing point-of-use (POU) filter. Tap water supplies were monitored in vending machines throughout Southern Arizona using solid block carbon (SBC) filters as a monitoring tool. Out of 48 SBC filters 54.2% were positive for at least one organism. The number of filters positive for total coliforms, E. coli, Enterococci, and enterovirus was 13, 5, 19, and 3, respectively, corresponding to 27.1%, 10.4%, 39.6%, and 6.3% of the total filters. These results suggest that the SBC filter can be used to monitor large volumes of treated drinking water and detect the incidence of indicators and pathogens. The study in Appendix B evaluated the fate of infectious prions in multiple water sources quantitatively utilizing a method that only detects infectious prions. A reduction of PrPˢᶜ was observed at 25°C and 37°C ranging between 0.41-log₁₀ and 1.4-log₁₀ after 1 week. After 8 weeks at 25°C and 37°C, inactivation ranged between 1.65-log₁₀ and 2.15-log₁₀. A maximum rate of inactivation in water occurred at 50°C, ranging from 2.0-log₁₀ and 2.51-log₁₀ after one week. The results from all types of water suggest that dissolved organic matter and temperature influence PrPˢᶜ infectivity. The study in Appendix C evaluated real-time sensors for monitoring microbial contaminants. Most sensor parameters evaluated exhibited an increase in sensor response to an increase in E. coli concentrations. Responses to E. coli concentrations at or below 10³ cfu/mL were very low due to near background levels, and responses to concentrations above 10⁶ cfu/mL exceeded threshold levels for sensors that use light scattering methods due to saturation in the flow cell. The data produced effectively shows that the sensors evaluated could be used to monitor microbial intrusion events in water distribution systems.
Type:
text; Electronic Dissertation
Keywords:
distribution systems; monitoring; pathogens; point-of-use; prions; water
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Soil, Water & Environmental Science; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Pepper, Ian L.
Committee Chair:
Pepper, Ian L.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleNovel Strategies for the Detection of Pathogens in Drinking Wateren_US
dc.creatorMiles, Syreetaen_US
dc.contributor.authorMiles, Syreetaen_US
dc.date.issued2010en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractTo protect public health, detection methods have been developed to monitor drinking water for pathogens. The goal of this dissertation is to evaluate and utilize novel methods that enhances detection and further reduces the risk of waterborne pathogens. The study in Appendix A developed a method to monitor the microbial quality of treated drinking water at the tap utilizing point-of-use (POU) filter. Tap water supplies were monitored in vending machines throughout Southern Arizona using solid block carbon (SBC) filters as a monitoring tool. Out of 48 SBC filters 54.2% were positive for at least one organism. The number of filters positive for total coliforms, E. coli, Enterococci, and enterovirus was 13, 5, 19, and 3, respectively, corresponding to 27.1%, 10.4%, 39.6%, and 6.3% of the total filters. These results suggest that the SBC filter can be used to monitor large volumes of treated drinking water and detect the incidence of indicators and pathogens. The study in Appendix B evaluated the fate of infectious prions in multiple water sources quantitatively utilizing a method that only detects infectious prions. A reduction of PrPˢᶜ was observed at 25°C and 37°C ranging between 0.41-log₁₀ and 1.4-log₁₀ after 1 week. After 8 weeks at 25°C and 37°C, inactivation ranged between 1.65-log₁₀ and 2.15-log₁₀. A maximum rate of inactivation in water occurred at 50°C, ranging from 2.0-log₁₀ and 2.51-log₁₀ after one week. The results from all types of water suggest that dissolved organic matter and temperature influence PrPˢᶜ infectivity. The study in Appendix C evaluated real-time sensors for monitoring microbial contaminants. Most sensor parameters evaluated exhibited an increase in sensor response to an increase in E. coli concentrations. Responses to E. coli concentrations at or below 10³ cfu/mL were very low due to near background levels, and responses to concentrations above 10⁶ cfu/mL exceeded threshold levels for sensors that use light scattering methods due to saturation in the flow cell. The data produced effectively shows that the sensors evaluated could be used to monitor microbial intrusion events in water distribution systems.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectdistribution systemsen_US
dc.subjectmonitoringen_US
dc.subjectpathogensen_US
dc.subjectpoint-of-useen_US
dc.subjectprionsen_US
dc.subjectwateren_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineSoil, Water & Environmental Scienceen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorPepper, Ian L.en_US
dc.contributor.chairPepper, Ian L.en_US
dc.contributor.committeememberGerba, Charles P.en_US
dc.contributor.committeememberRensing, Christopheren_US
dc.identifier.proquest10978en_US
dc.identifier.oclc752260953en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.