Banana Peels Could Help Clean Water

Minced peels shown to extract heavy metals from water

Banana peels have a new purpose other than wrecking havoc on unsuspecting pedestrians – they can remove heavy metals from water.

Scientists at São Paulo State University in Brazil have discovered that minced banana peels can bind and collect trace amounts of lead and copper in river water, making toxic metals 20 times easier to detect with crude equipment, according to a Discovery News report on the scientist’s research.

photo of a bananaJason Gulledge, on Flickr

Once refined for easy implementation on a global scale, the banana purification process could be of great use in developing countries where access to safe drinking water is still hard to come by.

Compounds in banana peels contain atoms of nitrogen, sulfur and organic compounds such as carboxylic acids, which can bind with metals in water. “I was at home eating some bananas when I had the idea, ‘Why not make something with this?’” says Gustavo Castro, an analytical chemist at the university’s Biosciences Institute told MSNBC. The scientists’ findings are published in the February 2011 issue of the Industrial & Engineering Chemistry Research journal.

Banana peels aren’t the first natural material that scientists have tried to use to remove heavy metals from water. Coconut fibers, sugarcane, peanut shells and other natural items have all had their turn. But Brazilian scientists were the first to ponder upon the banana.

The researchers used dried and minced peels for their experiments. They found that a purifier made of layers of minced peel could be used up to 11 times. Synthetic filters can be reused many more times, but natural materials like these peels are dramatically cheaper and do not require chemical processing to work. The banana peel filters worked even at high levels of pH, which means they could probably be effective filters for industrial and farm runoffs.

Still, no one is recommending at home use of banana peels to purify water. For while the peels might be able to extract heavy metals from water, it doesn’t have a proven ability to remove other contaminants that might be present, like germs.

Water contamination is something we all fret about. Heavy metals often leach into our water supplies from industrial and farm runoffs and have a toxic effect on us even when present in trace amounts. The result of prolonged drinking of metal-contaminated water accounts for nausea as well as brain damage.

With the population on Earth expanding to an unimaginable capacity, new technologies for producing safe drinking water are not just inevitable but essential for survival.

Get the Journal in your inbox.
Sign up for our weekly newsletter.

You Make Our Work Possible

You Make Our Work Possible

We don’t have a paywall because, as a nonprofit publication, our mission is to inform, educate and inspire action to protect our living world. Which is why we rely on readers like you for support. If you believe in the work we do, please consider making a tax-deductible year-end donation to our Green Journalism Fund.

Get the Journal in your inbox.
Sign up for our weekly newsletter.

The Latest

Land and Love in Melbourne

An Australian referendum to provide a political voice for First Peoples may have failed, but the push will continue.

Alda Balthrop-Lewis

A Canadian Corporation is Poisoning My Argentinian Community

We, the people of Jáchal, are fighting for the right to safe and clean water.

Saúl Zeballos

Climate Comedy Works. Here’s Why.

We all need some refreshing levity nowadays – especially during this politically heavy year.

Maxwell Boykoff Beth Osnes

Court Halts US Effort to Monitor Crypto Mining Energy Use

New requirement would cause 'irreparable injury' to industry amid surging electricity usage, federal judge rules.

Oliver Milman The Guardian

Saving the Bears of Abruzzo

In Italy, efforts to build a viable population of Marsican brown bears are underway.

Monique Gadella

River Guardians

Grassroots groups have taken it upon themselves to protect waterways in the southeastern US — and elsewhere around the world.

Melba Newsome Photographs by Madeline Gray