Photo Credit: Ali Wilson
A book that purifies water could help reduce waterborne illnesses in developing countries.
The Drinkable Book. I’m Bob Hirshon and this is Science Update.
In developing countries, many people have no choice but to drink contaminated water.
The latest number from the World Health Organization is 663 million people do not have access to clean drinking water, and because of that people will come down with waterborne illnesses.
That’s Carnegie Mellon chemist Theresa Dankovich, who created something called The Drinkable Book to help. It has tips on how to avoid waterborne disease, and its pages are filter paper, embedded with antimicrobial silver particles. Each sheet can disinfect 100 liters of water.
It’s really quite simple and easy to use, and also very affordable; the main cost is the cost of the paper itself.
At a meeting of the American Chemical Society, Dankovich presented promising results from Ghana, South Africa, and Bangladesh. I’m Bob Hirshon, for AAAS, the science society.
Making Sense of the Research
The Drinkable Book is a good example of science in the service of society. Carnegie Mellon chemist Theresa Dankovich saw a problem and came up with an efficient and inexpensive solution to it. How did she do this? And how successful is this solution?
Dr. Dankovich began researching antimicrobial paper as a PhD candidate in chemistry at McGill University in Montreal, Quebec. This research stemmed from her interest in understanding the potential risks and hazards of using nanomaterials in consumer products. It also stemmed from her desire to create a product that could be used in emergency situations in North America. But once she learned more about the problems caused by drinking water all over the world, she realized her invention had the potential to be “really good for humankind,” she explains.
During this time, she invented a bactericidal (destructive to bacteria) silver nanoparticle paper. Silver nanoparticles are what they sound like—tiny particles of silver that are between 1 and 100 nanometers in size. Additionally, she created a "green" method to produce the silver nanoparticles, using cheap and benign chemicals and processing. She developed and tested the technology for the paper over several years, working at McGill University in Canada and then at the University of Virginia, where she tested the paper in the lab using artificially contaminated water. The contaminated water gets poured through the paper. As the bacteria percolate through the paper, they absorb the silver ions so the water comes out clean with dead bacteria in it.
Success in the lab then led to field tests, which she conducted in Ghana. At first, she was testing the paper herself, not asking community members to test it. Doing this kind of testing, she found that the paper filtered almost 100 percent of the bacteria. Then she was contacted by designer Brian Gartside about collaborating with the non-government agency Water Is Life, an organization that aims to improve drinking water in developing countries through community-based action groups and the distribution of personal water filters. In these trials, conducted in Ghana, Bangladesh, and South Africa, the bacteria count in the water samples decreased by well over 99% on average—and in most samples, it dropped to zero.
"Greater than 90% of the samples had basically no viable bacteria in them, after we filtered the water through the paper," Dr. Dankovich said.
In order to get this technology into the hands of those who live in regions with contaminated water, Gartside came up with the idea of turning the paper into a book that could be translated into local languages. To use the paper, people just simply tear a page from the book and put it in a simple filter holder. In addition to this basic design, though, the researchers are considering alternatives that would work in different communities based on the types of water containers available in those communities—like a container called a "kolshi," an aluminum water jug used by the Bangladeshis.
In addition to making the technology more flexible, additional testing will likely be done to find out if the paper also can filter out other disease-causing microorganisms, like protozoa and viruses.
Now try and answer these questions:
- What prompted Dr. Dankovich to develop the bactericidal silver nanoparticle paper?
- What kind of testing did Dr. Dankovich conduct to find out if the paper would be able to remove bacteria from water? How did she conduct her research?
- What role did Brian Gartside play in the development of the drinkable book?
- What are the types of factors that need to be considered in order to make the book useful to those who need it?
- What other kinds of tests do you think Dr. Dankovich would need to conduct to make her invention useful to more people?
- Is there a challenge you know of for which you would want to try to find a solution? How could you go about doing that?
Triclosan and Staph is a Science Update about a common antibacterial agent in household products, which may actually promote the growth of Staph bacteria in people heavily exposed to it.
You can learn more about the Drinkable Book from this Wired article, "This Breakthrough Book about Water Safety Can Filter 4 Years' Worth of Clean Water."
You can extend on the ideas about thinking of new ways to solve problems presented in this Science Update by sharing these Science Updates with your students:
- Cell Phone Medicine Update focuses on how cell phones are being used as medical tools.
- Wheelchairs discusses how exchanging technology with some of the world's poorest countries is helping to build better wheelchairs.
The video, New Smartphone Microscope Can Diagnose Deadly Blood-borne Parasite, looks at how an innovative iPhone-based microscope can locate tiny Loa loa parasites in the blood at the point-of-care in a matter of minutes, potentially saving lives.