Nanotech Emergency Water Treatment Technology Devised

E coli bacteria magnified (USDA Agricultural Research Service/Wikimedia Commons)

Chemistry researchers at McGill University in Montreal, Canada have developed a technology for a cheap, portable, paper-based water treatment system when disasters like floods or earthquakes strike. The team’s findings were published earlier this month in the Journal of Environmental Science and Technology (paid subscription required).

The researchers, led by industrial chemistry professor Derek Gray, found a way of coating paper filters with silver nanoparticles. Gray and graduate student Theresa Dankovich, coated hand-sized sheets of absorbent porous paper, similar to blotter paper, with silver nanoparticles and then poured live E. coli and E. faecalis bacteria through it.

E. coli and E. faecalis bacteria are found in polluted drinking water and can cause intestinal diseases. Nanoparticles are pieces of matter produced at nanoscale size; 1 nanometer equals 1 billionth of a meter.

The results indicate that when the paper with even a small amount of silver — 5.9 milligrams of silver per dry gram of paper — the filter is able to kill nearly all the bacteria and produce water that meets the standards set by the U.S. Environmental Protection Agency. Gray’s team also found minimal loss of the added silver nanoparticles when used to filter the bacteria-laden water samples.

The nanoparticle-filter technology was tested only in the lab. The authors note that it could be developed into a solution for emergency situations, but probably not for long-term community needs.

Read more: Solar Powered Water Purifier Developed for Disaster Relief

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