Development of improved low-cost ceramic water filters for viral removal in the Haitian context

Abstract

Abstract:Household-based water treatment (HWT) is increasingly being promoted to improve water quality and, therefore, health status in low-income countries. Ceramic Water Filters (CWF) are used in many regions as sustainable HWT and have been proven to meet WHO microbiological performance targets for bacterial removal (2-4 log); however, the described viral removal efficiencies insufficient to significantly reduce associated risk to viral infection. With the objective of improving the viral removal efficiencies of ceramic water filters, new prototypes with different oxide compositions and firing atmospheres have been developed and evaluated. For removal efficiencies human adenoviruses, MS2 bacteriophage and E. coli were quantified in all prototypes. A new model of CWF that was fired in a reductive atmosphere presented virus and bacteria removal efficiencies greater than 3.0 log and 2.5 log, respectively, which would fulfill the viral targets that are recommended by the WHO. Ceramic characterization of the selected filters, which were fired in a reductive atmosphere, showed that a larger specific surface area than those of control filters and higher fraction of a positive Z-potential fraction are the most likely explanations for this increase in virus removal. Household-based water treatment (HWT) is increasingly being promoted to improve water quality and, 16 therefore, health status in low-income countries. Ceramic Water Filters (CWF) are used in many regions as 17 sustainable HWT and have been proven to meet WHO microbiological performance targets for bacterial 18 removal (2-4 log); however, the described viral removal efficiencies insufficient to significantly reduce 19 associated risk to viral infection. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 efficiencies human adenoviruses, MS2 bacteriophage and Escherichia coli were quantified in all prototypes. 23A new model of CWF that was fired in a reductive atmosphere presented virus and bacteria removal 24 efficiencies greater than 3.0 log and 2.5 log, respectively, which would fulfill the viral targets that are 25 recommended by the WHO. Ceramic characterization of the selected filters, which were fired in a reductive 26 atmosphere, showed that a larger specific surface area than those of control filters and higher fraction of a 27 positive Z-potential fraction are the most likely explanations for this increase in virus removal. 28 1

Removal of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli, ST98, in Water for Human Consumption by Black Ceramic Water Filters in Low-Income Ecuadorian Highlands

“…BCWFs have proved to be a viable alternative for eliminating bacteria and reducing viruses in contaminated water. Such filters, in addition to a complementary treatment, such as chlorination, can be used in homes to reduce enteric viruses and fully eliminate protozoa and bacteria, thus markedly diminishing the incidence of gastrointestinal diseases generated by contaminated water [21,22].…”

Silver and zinc oxide nanoparticle disinfection in water treatment applications: synergy and water quality influences

“…Similarly, Motshekga et al (2015) examined bacteria removal based on a combined solid-phase adsorption and disinfection and reported a silver-zinc disinfection synergy, but their work did not examine direct nanoparticle interventions under drinking water applications, or if such findings may be translated to technology. Finally, some recent research has also highlighted the potential of co-metal disinfection within technological applications; however, the limited literature in this domain has focused particularly on silver-copper and silver-iron combinations with variable results (Brown & Sobsey 2009;Guerrero-Latorre et al 2015;Lucier et al 2017;Ehdaie et al 2020). An important research gap thus remains in terms of how combined metal nanoparticles, and silver-zinc combinations specifically, may synergistically disinfect bacteria within a water treatment application, and particularly within point-of-use water treatment technology.…”

Adopting a Preparatory Strategy to Respond to Water Security Issues Arising from Geo-Hazards

“…Additional significance of the effectiveness of ceramic water filters has been provided by Mohamed [22] who assessed the microbiological effectiveness of several household water treatment and safe storage (HWTS) options in-situ in Tanzania and found that ceramic pot filter improved microbial water quality by reducing thermo tolerant (TTC) coliforms by 99.5%. Further, Guerrero-Latorre [23] reported that CWF that was fired in a reductive atmosphere presented virus and bacteria removal efficiencies greater than 3.0 log and 2.5 log, respectively and ceramic characterization of the selected filters, which were fired in a reductive atmosphere, showed that a larger specific surface area than those of control filters and higher fraction of a positive Z-potential fraction are the most likely explanations for this increase in virus removal.…”