Is That a Banana in Your Water?

original article:

http://news.nationalgeographic.com/news/2011/03/110311-water-pollution-lead-heavy-metal-banana-peel-innovation/

snippets:

Banana peels are no longer just for composting or comedy shows: New science shows they can pull heavy metal contamination from river water.

Traditionally, water quality engineers have used silica, cellulose, and aluminum oxide to extract heavy metals from water, but these remediation strategies come with high price tags and potentially toxic side effects of their own.

Bananas, on the other hand, appear to be a safe solution. Banana peels also outperform the competition, says Gustavo Castro, a researcher at the Biosciences Institute at Botucatu, Brazil, and a coauthor of a new study on this new use of the fruit’s peel.

For the study, Castro and his team dried and ground banana peels, then combined them in flasks of water with known concentrations of metals. They also built water filters out of peels and pushed water through them.

In both scenarios, “the metal was removed from the water and remained bonded to the banana peels,” Castro said, adding that the extraction capacity of banana peels exceeded that of other materials used to remove heavy metals.

Previous work has shown that other plant parts—including apple and sugar cane wastes, coconut fibers, and peanut shells—can remove potential toxins from water.