Performance and Acceptance of Novel Silver-Impregnated Ceramic Cubes for Drinking Water Treatment in Two Field Sites: Limpopo Province, South Africa and Dodoma Region, Tanzania

Abstract

Diarrheal disease and environmental enteropathy are serious public health concerns in low-income countries. In an effort to reduce enteric infection, researchers at the University of Virginia developed a new point-of-use (POU) water treatment technology composed of silver-impregnated porous ceramic media. The ceramic is placed in a 15 L plastic container of water in the evening and the water is ready to drink in the morning. The purpose of this study was to assess field performance and local acceptance of technology in two communities in Limpopo Province, South Africa, and one community in Dodoma Region, Tanzania. Performance was determined by coliform testing of treated water. Acceptance was determined using data from 150 household surveys and a nine-day structured observational study at a local primary school. At the primary school, 100% of treated water samples had no detectable levels of total coliform bacteria (TCB) in buckets filled by researchers. For all treated school buckets, 74% of samples achieved less than or equal to 1 CFU/100 mL and 3.2 average log reduction of TCB. Laboratory experiments with highly contaminated water diluted to lower turbidity achieved 4.2 average log reduction of TCB. Turbid water (approximately 10 NTU) only achieved 1.1 average log reduction of TCB; turbidity and organic material may have interfered with disinfection. The Tanzania primary school (deep groundwater source) had less turbid water and achieved 1.4 average log reduction of TCB; however, it did have high chloride levels that may have interfered with silver disinfection. The surveys revealed that the majority of people retrieve, store, and dispense water in ways that are compatible with the new technology. The willingness-to-pay study revealed potential customers would be willing to pay for the technology without subsidies. The results of this study indicate that this novel silver-impregnated ceramic POU water treatment technology is both effective and appropriate for use in the study communities.

Challenges to Sustainable Safe Drinking Water: A Case Study of Water Quality and Use across Seasons in Rural Communities in Limpopo Province, South Africa

“…In addition, there was little to no detectable residual chlorine in the municipal tap water to prevent recontamination. A previous study performed in an adjacent community showed higher household treatment levels; however, this may have been due to intervention studies in that community (the community in question was excluded from this study because of previous interventions) [47]. The study also concurred that boiling was the most common method employed.…”

Impact of Low-Cost Point-of-Use Water Treatment Technologies on Enteric Infections and Growth among Children in Limpopo, South Africa

“…Almost all mothers (n = 390, 96.5%) completed at least secondary school education and were on average 28 years old (SD: 6.7; Table 1). The mean monthly income for the household was 1920 South African Rand (ZAR) (approximately USD135 in June 2016), which is consistent with that of previous studies in the area, 24 and households had on average 2.4 children younger than 15 years (SD: 1.2). The majority of participants most frequently obtained drinking water from the municipality (piped into their yard, n = 91, 22.5%; or from a public stand pipe, n = 77, 19.1%) or from surface water through a piped system (into their yard, n = 100, 24.8%; or from a public stand pipe, n = 46, 11.4%).…”

“…Both technologies have proven to be highly effective in treating water, showing up to a 3.2 log reduction in total coliform bacteria during field studies in South Africa and Tanzania. 23,24 Ceramic water filters also reduced diarrheal rates among HIV-positive individuals in Limpopo, South Africa, by 79%. 15 However, it is unknown whether the use of these technologies can translate to improvements in child health outcomes, particularly linear growth.…”

Optimization of Silver Ion Release from Silver-Ceramic Porous Media for Household Level Water Purification

“…The results from this study suggest that this novel silver impregnated ceramic technology is effective, safe, socially acceptable, and commercially viable. Kahler et al [37] reported the economic viability of this product elsewhere. They also conducted a field study in South Africa, and examined a cost model based on a "willingness to pay" study.…”