20 August 2015

'Drinkable book' could give millions access to clean water

AUGUST 17, 2015

With pages that can filter out bacteria, the drinkable book may solve a major public health problem for the 750 million people worldwide without access to clean drinking water.

Normally, pouring water onto a book is an unfortunate accident. Aside from using the Yellow Pages to mop up a spill, there aren’t many reasons to intentionally get a book wet.

Scientists have just come up with a really good reason, one that could be an answer to water scarcity around the world.

The “drinkable book” is not just a manual on why and how to drink clean water; the pages themselves are imbued with silver and copper particles that act as water filters, making even the filthiest water potable when torn out and used with a special holding device. With 750 million people worldwide lacking access to clean water, an easy and inexpensive solution has been a pressing yet elusive need.

Dr. Theresa Dankovich has been working on developing the innovation since her days as a Ph.D. candidate at McGill University. Now continuing the project through postdoctoral research at Carnegie Mellon University, Dr. Dankovich presented the results of recent trials in South Africa, Ghana, and Bangladesh at the 250th national meeting of the American Chemical Society in Boston.

At 25 different testing sites, the filter paper successfully removed more than 99 percent of bacteria, passing EPA standards and yielding 100 liters of clean water per page. According to the researchers, one book could last a person four years.

"There was one site where there was literally raw sewage being dumped into the stream, which had very high levels of bacteria,”Dankovich told BBC News. "But we were really impressed with the performance of the paper; it was able to kill the bacteria almost completely in those samples. And they were pretty gross to start with, so we thought – if it can do this, it can probably do a lot."

The silver and copper particles on the pages absorb microbes as water soaks the paper. Bits of copper and silver do tend to seep into the filtered water, but the researchers say the levels are no cause for concern.

The encouraging results of the trials have given Dankovich and the team permission to address the next challenge: production. Currently, Dankovich and her students produce the paper by hand, the BBC reported, through her nonprofit pAge Drinking Paper. They are working in conjunction with the organization WATERisLIFE, but hope to start manufacturing the filters on a larger scale “to get it into people's hands.”

While other scientists agree that the drinkable book shows promise, several have pointed out that though the filters remove bacteria, they have not been evaluated on their ability to eliminate other potential contaminants.

“I would want to see results for protozoa and viruses," Tufts University environmental engineer Dr. Daniele Lantagne told the BBC. "This is promising but it's not going to save the world tomorrow. They've completed an important step and there are more to go through."

Dr. Kyle Doudrick of the University of Notre Dame reiterated the concern and added that the invention’s success would be contingent on people understanding how to use it and how often to change the filter page.

"Overall, out of all the technologies that are available – ceramic filters, UV sterilisation and so on – this is a promising one,” Dr. Doudrick told the BBC, “because it's cheap, and it's a catchy idea that people can get hold of and understand."

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