Fruit peels may be used as life-saving water filters: NUS research

NUS lead researcher Ramakrishna Mallampati (above), has developed low-cost, low-energy and environmental friendly water filtration techniques using fruit and vegetable peels as filters. -- ST PHOTO: SEAH KWANG PENG
NUS lead researcher Ramakrishna Mallampati (above), has developed low-cost, low-energy and environmental friendly water filtration techniques using fruit and vegetable peels as filters. -- ST PHOTO: SEAH KWANG PENG

Fruit peels are used as compost by the environmentally conscious worldwide. But the throwaway item could soon have an even higher calling - saving lives.

Tomato and apple peels act like a sponge in polluted water, vastly reducing levels of heavy metals, pesticides and dyes, researchers at the National University of Singapore have found. Their two-year study found, for example, that the peel from eight tomatoes could in an hour almost completely remove heavy metal ions such as lead from a litre of water.

Their findings could pave the way for a readily available and low-cost way to make drinking water safer for the nearly 800 million people worldwide without access to clean water.

This could especially be crucial for those in remote regions without easy access to water purification devices, said lead researcher Ramakrishna Mallampati, and where groundwater close to villages is contaminated by industrial pollution.

"There are many products already in the market, but ... developing countries cannot afford these costly technologies," he said. Some of these include Lifestraw, a personal water filter in the form of a straw that retails for about $25.

Fruit peel, on the other hand, is available throughout the world as a waste product from processed food, he added.

The researchers are working with national water agency Public Utilities Board to test if the peels are effective on a larger-scale. Test results are expected next month.

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