17 March 2011 | ES | EN
The peels can perform even better than conventional purification materials
[MONTEVIDEO] Banana peels can be used to purify drinking water contaminated with toxic heavy metals such as copper and lead, according to a study.
Researchers from the Bioscience Institute at Botucatu, Brazil, said that the skins can outperform even conventional purifiers such as aluminium oxide, cellulose and silica. These have potentially toxic side effects and are expensive.
The team's method follows previous work that showed that plant parts, such as apple and sugar cane wastes, coconut fibres and peanut shells, can remove toxins from water.
These natural materials contain chemicals that have an affinity for metals.
"I was at home eating bananas when I had the idea: 'Why not make something with this?'" Gustavo Rocha de Castro, a researcher at the institute and co-author of this study, told SciDev.Net.
De Castro and colleagues dried the peels in the sun for a week, ground them and added them to river water containing known concentrations of copper and lead. They found that the peels absorbed 97 per cent of the metals after just one hour.
The peels were tested in the lab and worked perfectly. Eventually their efficiency reduces, at which point the metals should be removed from the skins so that they can be disposed of safely.
Castro said that, although the peels were tested only on copper and lead, the material could also work on cadmium, nickel and zinc.
But he warned that this sort of filter is better suited to industrial purposes and cannot be used for water purification at home as the extraction capacity of banana skins depends on the particle size of the heavy metals — and this is difficult to measure.
Dimitris Kalderis, a wastewater treatment expert at the Department of Environmental Engineering in the Technical University of Crete, Greece, said: "The results are very promising, and the banana peel process has proven to be a cost-effective and quick alternative to conventional methods".
"I think that a small automated system to use either at home or at a central point for multiple families could be developed. The knowledge is there, what we need right now is innovation and construction."
The study was published in Industrial & Engineering Chemistry Research last month (16 February).
Industrial & Engineering Chemistry Research doi: ie101499e (2011)
Jose ( school | Uganda )
19 March 2011
On banana skins, I think it will be good if this technology extends to the local people down here in our homes so that instead of throwing away the peels, we instead use them for purifying our water. Here in my country Uganda there are districts were people share the same ponds to feed their animals and for domestic use, so you find that people drink water with alot of toxic materials. Otherwise i'm so happy for this.
Dr.A.Jagadeesh ( Nayudamma Centre for Development Alternatives | India )
21 March 2011
There are other traditional methods which are used in water purification.Moringa seed, stricnos potato rum seeds, ocimum sanctum leaves etc., People put water in a copper vessel overnight and drink it in the morning. Also bronze vessels are known to purify water. In Bangladesh three or four folds of silk cloth is used to filter impure water.
Dr.A.Jagadeesh Nellore (AP), India
osbert ( Uganda )
22 March 2011
Banana skins! Purification ,is an amazing innovation. Am sure many people will make use of this purification method.
Robert Natumanya ( Uganda )
22 March 2011
I agree, it is good if people in our communities can benefit from such technology, but it will require first to be standardised. I have done research work on the potential of plants seeds(jackfruit,jambula and moringa) as water coagulants, the results obtained are also promising. Natural materials of plant and animal sources need to investigated as coagulants of water since they hold promise for our future. They are green technology, cheap, easy to use by any person and materials for use are locally available for communities. It would also be very interesting to check other water quality parameters of water treated with banana peels apart from metal ions.
Rielle ( Canada )
22 March 2011
Aren't banana peels full of harmful pesticides? Banana pickers are known to have serious health problems resulting from them. I therefore suppose it's important to say that it's mandatory to use organic bananas for this process in order not to contaminate the water.
Dr. Wahabi B. Asiru ( Federal Instiitute of Industrial Research, Oshodi, Lagos | Nigeria )
24 March 2011
This is a breakthrough in the utilization of waste especially for Africa. I will be glad if this kind of research is publish in journal to pave way for more discoveries by other scientists in the world so that local people can make use of the technology.
Vinod Dhargalkar ( India )
24 March 2011
This is very interesting and innovative use of banana skin for water purification. It should be standardized so that it can be used for domestic and industrial purposes. I had worked on the similar line during my research tenure using marine plants (seaweeds) powder to produce potabel water from the industrial waste and it had shown promising results. The process has been patented. Dr Vinod Dhargalkar, ex Scientist, National Institute of Oceanography, Goa, India.
rizwan ( Pakistan )
1 April 2011
I'm convinced of using banana peels for the purpose of water purification. It's cheap and natural, but still investigation is required with background knowledge. I'll put this technique on trials in drinking water to investigate its effectiveness against arsenic.
gopalkrishna ( college of medical sciences ,bharatpur,nepal | Nepal )
2 April 2011
It's a very fantastic, cheap and innovative technology. But what about other water quality parameters particularly microbiological aspect. If these are also eliminated other than metals only then is it wonderful.
Dr. Gopal Krishna, Bharatpur, Nepal.
Olaniyan Olawlae ( Netherlands )
6 April 2011
This is a very good idea. I think there may be a need to study different species of banana in order to carefully gain more insight into this promising and relatively affordable water purifier. The best method of maximising the benefit should also be explored as well.
Muriira ( Kenya Bureau of Standards | Kenya )
12 January 2012
This is an amazing innovation. Banana peels are found in many localities and this technique would easily be adopted by many people in the world. Keep up for the brilliant study. Muriira (Kenya)
pintumaster1 ( India )
12 January 2012
This is good but why can they not give informtion about the heavy metals. How is it processed, can any one tell me? And is there any cheap filtering process available?
FA Adekola ( University of Ilorin, Nigeria | Nigeria )
12 January 2012
This is highly commendable because of its simplicity and efficacy. More research needs however to be done on its standardization.
Dr Atayese, M. olaoye ( University of Agriculture Abeokuta, Nigeria | Nigeria )
13 January 2012
This is by no small mesure a welcome development. Caution should however be exercised with respect to posible further contamition of water by secondary metabolites and mycotoxins from peels. We should also strive to know at what stage of ripening the peel is best effective.
Engineer Jalal ( Pakistan )
16 January 2012
It is a good inovation especially in Pakistan where there are lots of problems in drinking water... and also in Pakistan there is huge production of banana, so it will be economical, we'll hope that soon get a good news.
Luke ( France )
17 January 2012
Can somebody please explain to me how to make it in my house? How do you make an "apparatus"? Thank you. :)
aswin simatupang ( Indonesia )
19 January 2012
I want to try this at home!
Timothy Ali ( Nuhu Bamalli Polytechnic,Zaria. | Nigeria )
21 January 2012
This is real good news. Heavy metal pollution will soon be a thing of the past if it is established that the method has minimal side effects.
supah scientist3.14 ( United States of America )
21 January 2013
How do you dry the bananas?
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