ingest cdrApp 2019-01-04T15:04:16.412Z 2a9effba-8beb-4434-9ac1-3dd15c1ac330 modifyDatastreamByValue RELS-EXT fedoraAdmin 2019-01-04T15:05:12.894Z Setting exclusive relation addDatastream MD_TECHNICAL fedoraAdmin 2019-01-04T15:05:28.921Z Adding technical metadata derived by FITS addDatastream MD_FULL_TEXT fedoraAdmin 2019-01-04T15:05:58.565Z Adding full text metadata extracted by Apache Tika modifyDatastreamByValue RELS-EXT fedoraAdmin 2019-01-04T15:06:23.516Z Setting exclusive relation modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2019-01-22T16:03:36.844Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2019-03-20T13:11:23.542Z Katie Friedman Author Department of Environmental Sciences and Engineering Gillings School of Global Public Health Evaluation of Antimicrobial Metals for Enhanced Performance of Household Water Treatment Methods Household water treatment and safe storage (HWTS) technologies play an increasingly important role in the reduction of global burden of waterborne disease, putting the capacity to treat unsafe drinking water directly into the hands of the consumer without reliance on centralized treatment or piped water systems. HWTS technologies differ in their ability to reduce viral, bacterial, and parasitic contaminants. Microbial reduction targets for HWTS performance set by the World Health Organization (WHO) are based on acceptable risk levels and log10 reductions. One approach to improve microbial reductions to meet performance targets is the incorporation of antimicrobial metals, which have been utilized for disinfection for centuries. The aim of this research was to evaluate copper, silver, and iron incorporated into ceramic water filters for improved E. coli and MS2 bacteriophage reductions and to determine the kinetics and magnitude of E. coli and MS2 inactivation with copper and silver ions as additives to water for solar disinfection (SODIS) and safe storage. The incorporation of copper, silver, and iron additives generally improved the reductions of E. coli by the ceramic water filters to reach the WHO Highly Protective (4 log10 reduction) target for bacteria, but viral reductions remained well below the WHO Protective (3 log10 reduction) target. Leached copper and silver ions in the filter effluent contributed to additional disinfection of E. coli and MS2 with overnight storage time. For stored water, copper and silver ions at concentrations allowable for drinking water showed the capacity to meet WHO Protective targets for virus reductions after overnight storage due to an apparent synergistic disinfection effect between copper and silver ions. Copper and silver ion additives also significantly increased the inactivation rates of bacteria and more notably viruses in SODIS. E. coli reductions were evaluated on selective and non-selective media, and differences in log10 reductions indicated the ability of E. coli to resuscitate initially after sub-lethal injury by metals and/or solar irradiation, but this effect decreased as exposure times increased. Incorporation of antimicrobial metal additives for ceramic water filters, SODIS, and stored water requires further study but shows promise for improved microbial reductions by HWTS technologies. Winter 2018 2018 Environmental engineering Microbiology Environmental science Antimicrobial metals, Ceramic water filters, Copper, Disinfection, Household water treatment and safe storage, Silver eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Environmental Sciences and Engineering Mark Sobsey Thesis advisor Orlando Coronell Thesis advisor Jagannadham Kasichainula Thesis advisor Pete Kolsky Thesis advisor Gertjan Medema Thesis advisor text Katie Friedman Creator Department of Environmental Sciences and Engineering Gillings School of Global Public Health Evaluation of Antimicrobial Metals for Enhanced Performance of Household Water Treatment Methods Household water treatment and safe storage (HWTS) technologies play an increasingly important role in the reduction of global burden of waterborne disease, putting the capacity to treat unsafe drinking water directly into the hands of the consumer without reliance on centralized treatment or piped water systems. HWTS technologies differ in their ability to reduce viral, bacterial, and parasitic contaminants. Microbial reduction targets for HWTS performance set by the World Health Organization (WHO) are based on acceptable risk levels and log10 reductions. One approach to improve microbial reductions to meet performance targets is the incorporation of antimicrobial metals, which have been utilized for disinfection for centuries. The aim of this research was to evaluate copper, silver, and iron incorporated into ceramic water filters for improved E. coli and MS2 bacteriophage reductions and to determine the kinetics and magnitude of E. coli and MS2 inactivation with copper and silver ions as additives to water for solar disinfection (SODIS) and safe storage. The incorporation of copper, silver, and iron additives generally improved the reductions of E. coli by the ceramic water filters to reach the WHO Highly Protective (4 log10 reduction) target for bacteria, but viral reductions remained well below the WHO Protective (3 log10 reduction) target. Leached copper and silver ions in the filter effluent contributed to additional disinfection of E. coli and MS2 with overnight storage time. For stored water, copper and silver ions at concentrations allowable for drinking water showed the capacity to meet WHO Protective targets for virus reductions after overnight storage due to an apparent synergistic disinfection effect between copper and silver ions. Copper and silver ion additives also significantly increased the inactivation rates of bacteria and more notably viruses in SODIS. E. coli reductions were evaluated on selective and non-selective media, and differences in log10 reductions indicated the ability of E. coli to resuscitate initially after sub-lethal injury by metals and/or solar irradiation, but this effect decreased as exposure times increased. Incorporation of antimicrobial metal additives for ceramic water filters, SODIS, and stored water requires further study but shows promise for improved microbial reductions by HWTS technologies. 2018 2018-12 Environmental engineering Microbiology Environmental science Antimicrobial metals; Ceramic water filters; Copper; Disinfection; Household water treatment and safe storage; Silver eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Environmental Sciences and Engineering Mark Sobsey Thesis advisor Orlando Coronell Thesis advisor Jagannadham Kasichainula Thesis advisor Pete Kolsky Thesis advisor Gertjan Medema Thesis advisor text Katie Friedman Creator Department of Environmental Sciences and Engineering Gillings School of Global Public Health Evaluation of Antimicrobial Metals for Enhanced Performance of Household Water Treatment Methods Household water treatment and safe storage (HWTS) technologies play an increasingly important role in the reduction of global burden of waterborne disease, putting the capacity to treat unsafe drinking water directly into the hands of the consumer without reliance on centralized treatment or piped water systems. HWTS technologies differ in their ability to reduce viral, bacterial, and parasitic contaminants. Microbial reduction targets for HWTS performance set by the World Health Organization (WHO) are based on acceptable risk levels and log10 reductions. One approach to improve microbial reductions to meet performance targets is the incorporation of antimicrobial metals, which have been utilized for disinfection for centuries. The aim of this research was to evaluate copper, silver, and iron incorporated into ceramic water filters for improved E. coli and MS2 bacteriophage reductions and to determine the kinetics and magnitude of E. coli and MS2 inactivation with copper and silver ions as additives to water for solar disinfection (SODIS) and safe storage. The incorporation of copper, silver, and iron additives generally improved the reductions of E. coli by the ceramic water filters to reach the WHO Highly Protective (4 log10 reduction) target for bacteria, but viral reductions remained well below the WHO Protective (3 log10 reduction) target. Leached copper and silver ions in the filter effluent contributed to additional disinfection of E. coli and MS2 with overnight storage time. For stored water, copper and silver ions at concentrations allowable for drinking water showed the capacity to meet WHO Protective targets for virus reductions after overnight storage due to an apparent synergistic disinfection effect between copper and silver ions. Copper and silver ion additives also significantly increased the inactivation rates of bacteria and more notably viruses in SODIS. E. coli reductions were evaluated on selective and non-selective media, and differences in log10 reductions indicated the ability of E. coli to resuscitate initially after sub-lethal injury by metals and/or solar irradiation, but this effect decreased as exposure times increased. Incorporation of antimicrobial metal additives for ceramic water filters, SODIS, and stored water requires further study but shows promise for improved microbial reductions by HWTS technologies. 2018 2018-12 Environmental engineering Microbiology Environmental science Antimicrobial metals; Ceramic water filters; Copper; Disinfection; Household water treatment and safe storage; Silver eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Mark Sobsey Thesis advisor Orlando Coronell Thesis advisor Jagannadham Kasichainula Thesis advisor Pete Kolsky Thesis advisor Gertjan Medema Thesis advisor text Friedman_unc_0153D_18259.pdf uuid:b48ad7e9-2995-48d0-9074-624ad81f28f6 2020-12-31T00:00:00 2018-12-12T18:20:56Z proquest application/pdf 3766855