Water study: Is colloidal silver necessary for bacteria removal?

Sep 01, 2010
Heinley points out the presence of E. coli in a water sample.

(PhysOrg.com) -- Nicole Heinley, a graduate student at Missouri University of Science and Technology, traveled to Guatemala twice in the past year to conduct research on ceramic pot filters that are used locally to remove bacteria from water. Now, Heinley's findings are about to be published in the Journal of Water Science and Technology.

Ceramic pot filters, which are made out of sawdust and clay, have been around in poor countries for hundreds of years. The focus of Heinley's research is on the colloidal silver -- or lack of it -- that is typically used to line the filters. The silver mixture is thought to have disinfection properties -- but the actual disinfection mechanism of the silver is poorly understood.

Heinley wanted to find out if the colloidal silver, which is the most expensive part of the filters, is necessary at all. "It's the only material that has to be imported to manufacture the filters," she says. "The remaining materials -- sawdust and clay -- are available locally."

In the journal article, Heinley and Dr. Curt Elmore, associate professor of geological engineering at Missouri S&T, conclude that the silver may not be necessary to effectively remove from source water. In their study, filters not lined with silver removed a high rate of E. coli.

"Additional, long-term studies of filters without silver should be undertaken in order to further investigate the issue," Heinley says.

Heinley and Elmore traveled to Guatemala with students from a geological engineering class during winter break and spring break earlier this year. Heinley collected contaminated water samples from a little river in the city of Antigua and studied the structure of the ceramic pot filters available locally. Back at Missouri S&T, she continued the research.

Explore further: Tourists evacuated amid Iceland volcano concerns

More information: The article, "Bacteria Removal Effectiveness of Ceramic Pot Filters Not Applied with Colloidal Silver," was recently accepted for publication by the Journal of Water Science and Technology. The publication date is pending.

add to favorites email to friend print save as pdf

Related Stories

New filter promises clean water for millions

Jan 19, 2005

A handful of clay, yesterday’s coffee grounds and some cow manure are the simple ingredients that could bring clean drinking water to developing countries around the globe. An innovative new technology, dev ...

In the World: Clean Water for Ghana

Apr 30, 2010

Nearly 1 billion people do not have access to clean drinking water. The problem is particularly dire in Ghana, where diarrhea causes 25 percent of all deaths of children below the age of five each year, according ...

Recommended for you

Water crisis threatens thirsty Sao Paulo

47 minutes ago

Sao Paulo is thirsty. A severe drought is hitting Brazil's largest city and thriving economic capital with no end in sight, threatening the municipal water supply to millions of people.

Climate change: meteorologists preparing for the worst

6 hours ago

Intense aerial turbulence, ice storms and scorching heatwaves, huge ocean waves—the world's climate experts forecast apocalyptic weather over the coming decades at a conference in Montreal that ended Thursday.

Sunlight, not microbes, key to CO2 in Arctic

6 hours ago

The vast reservoir of carbon stored in Arctic permafrost is gradually being converted to carbon dioxide (CO2) after entering the freshwater system in a process thought to be controlled largely by microbial ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

exBrit
not rated yet Sep 01, 2010
I'm old enough to remember the essential hygiene in English butcher's shops; namely wooden chopping blocks and sawdust on the floors. It is also well established that wooden cutting blocks are safer in the kitchen than plastics-based alternatives. The antibacterial action of wood and sawdust is well reported in the literature. Without it, trees would never survive to maturity.
perfectmus
not rated yet Sep 16, 2010
In Iraq, they found the Baghdad Battery, interestingly enough, they also found gold and silver plated utinsils. Silver has been used to kill bacteria thousands of years ago. Colloidal Silver now has a new form, called colloidal silver atoms, aka colloidal silver 3000 PPM, you can read more about it here: http://www.gold2l...oms.html