Socially embedded and sustained point-of-use disinfection : enhancing silver nanoparticle enabled ceramic water filters with a Navajo pottery technique

For the nearly 800 million people that lack access to safe drinking water, point-of-use water treatment systems are a common solution to help provide potable water. Despite the availability of numerous treatment devices, failure at the implementation stage is common, mostly due to an oversight of the target community’s needs and thereby creating barriers for adoption. A classic example of communities with barriers against outside influence is the Navajo Nation, which also has extensive water contamination. Developing a water treatment solution for the Navajos thus has to consider community sentiment and empower the solution with local materials or century-old practices, which can possibly overcome such barriers and facilitate long-term adoption.

This two-pronged dissertation centers around socially-aware water treatment. The first part is community-engaged research, aimed at identifying social drivers that underlie a community’s relationship with water and assessing the need for water treatment technologies. A qualitative study on water in indigenous communities in Mexico helped to identify the diverse drivers relating to water use. This aspect was further developed utilizing structural equation modeling to quantitatively link factors relating to water in the colonias in the United States. A systematic study on water quality in these unincorporated communities was also completed.

The development of a socially-aware technology is the connecting link between the community-engaged research and the scientific laboratory research, which focuses the design of a socially appropriate nano-enabled ceramic device for disinfection. A natural polymer, Navajo pottery glaze of pinyon resin, was utilized to apply silver nanoparticles to ceramic water filters. The use of this material may help to facilitate adoption while rendering needed technological advancement to these widely used water treatment devices.

Results show that embedding silver nanoparticles onto ceramic with this polymer allows for sustained dissolution of ionic silver in a range of waters and serves as a barrier to passivation from sulfide and chloride. The polymer was also found to control biofouling and to be toxic against Gram-positive bacteria. Overall, the community-engaged research provides valuable insight on understudied communities through innovative statistical methods, and the scientific research is one of the first to integrate traditional Native knowledge with novel materials engineering.