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Risha Jasmine Nathan graduated from the University of Otago last weekend with a doctorate - her research investigated how kiwifruit and cucumber peels could be used to purify drinking water.
"I’m thrilled," Dr Nathan said about her research.
There were win-win benefits in making constructive use of an agricultural waste product while improving water quality by removing potentially-damaging heavy metals, including lead.
She was delighted to be involved in studying "this revolutionary water decontamination technique".
Some people turn their kiwifruit and cucumber peels into compost or simply throw them out with the rubbish.
But Indian-born Dr Nathan has spent three and a-half years studying how such simple substances can become cheap, efficient and easily available water filters for low-income populations needing cleaner drinking water.
Most recently a student in the university’s department of pharmacy and toxicology, she first discovered the concept of peels becoming purifiers during her earlier master’s dissertation research in India.
She later undertook studies with unmodified banana peel in water containing lead, and got "amazing results".
Born in Prayagraj, Uttar Pradesh, North India, she has focused her biosorption technique on the peels from apples, bananas, cucumbers, kiwifruit, oranges and potatoes.
The peels were transformed into beads and sodium alginate, an extract of brown seaweed, was used to make them more efficient as biosorbents. Arsenic, cadmium, chromium, copper, mercury, lead and nickel could be removed from a cocktail solution.
"It is a low-cost solution to a serious problem," she said.