Large portions of the Navajo tribe, a Native American people living in the southwestern United States, lack access to clean drinking water, something that has increased in many parts of the United States in recent years.
So a research team led by engineers from the University of Texas at Austin changed that, developing a new water purification solution for tribal members.
Working with the community
The team lined the pottery with pine tree resin collected on a 71,000-square-kilometre Navajo reservation in Arizona, New Mexico and Utah, then combined it with silver nanoparticles in the pots to use as a water purifier to make it drinkable.
“Making water purification technology cheap doesn’t solve all the problems, and making it effective doesn’t solve everything either,” Naveed Saleh, a professor in the Department of Civil, Architectural and Environmental Engineering and one of the project leaders, said in the UT Austin press release. You think about the people you’re making this for.”
That’s what the researchers did, as they worked closely with Diana Tsu, a third-generation potter from Arizona and also a co-author of the paper published in the journal Environmental Science and Technology, to create a simple device for users. All they have to do is pour water. In pottery, painted pottery removes bacteria from the water and creates clean, drinkable water.
The researchers say the Navajo tribe has a history of mistrust of outsiders, and this makes it unlikely that people there will adopt new technology that was made entirely by others, so using pottery, working with the community, and relying on local materials was important to the effectiveness of this project.
“Navajo pottery is at the heart of this innovation, because we hoped it would bridge the trust gap,” says Louis Stetson Rawls, a Ph.D. from the University of Texas. “Pottery is sacred to the Navajo, and using its materials and techniques can help them feel more comfortable adopting solutions.” New.
The secret is in the details
The researchers say in the press release that using silver particles to purify water is not the main innovation; others have used this technology in the past. But the key was controlling the release of the silver nanoparticles used. Silver nanoparticles, in large quantities, mix with some chemicals – such as chloride and sulfide – in untreated water, creating a “toxic layer” that can reduce the effectiveness of silver nanoparticle disinfection. On clay lining.
So the researchers used materials abundantly available in the community environment, including pine tree resin, to mitigate the uncontrolled release of silver particles during the water purification process. The result was an innovation that was cheap, effective, and socially acceptable, as the materials used and the process of making the pots cost only less than $10 per pot.
“This is just the beginning of trying to solve a local problem for a specific group of people,” Saleh says, “but the technical progress we have achieved can be used around the world to help other communities.”
He adds that the next step for researchers is to develop the technology and find other materials and techniques to help communities use materials available in their areas to help produce fresh, drinkable water. The researchers are not seeking to commercialize the research, but are keen to share it with potential local partners.