Approximately 2.1 billion people around the world lack access to safe and clean water, and more than 250 million kidney dialysis filters are thrown away every year.

Israeli professor Yoram Lass has a solution that could help address both problems.

Lass developed a process for cleaning water using dialysis filters that led to the creation of NUFiltration, an Israel-based startup.

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NUFiltration’s flagship device is a portable gadget that relies on a hand-crank and can purify up to 500 liters of water an hour. The device, a kind of filter, only needs to be replaced once every few years.

The filtering devices use hemodialysis filters, typically used to purify blood for patients whose kidneys are not performing regularly, to purify water.

NUFiltration takes these used filters and, after sanitizing them, uses them to trap water impurities in the center of the filtration device.

Since hemodialysis filters must be fine enough to filter out tiny blood impurities, they are ideal for catching similar impurities in water.

NUFiltration not only offers a creative solution to generating clean water but also helps recycle dialysis filters, which are discarded after one use to meet stringent sanitation standards.

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Observing the waste generated by the single-use filters, Lass was inspired to create water filters and patented his simple, effective idea. In 2011, he sold the patent to Israeli entrepreneur Mino Negrin who then founded NUFiltration.

“[Lass’ idea] was genius,” Negrin told Israel21c. “The simplicity of it caught my eye immediately. It could filter out every micro-biological pollutant: viruses, bacteria, fungi.”

On top of being portable and easy to use, the filters are low-cost, as used dialysis filters cost less than a dollar.

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NUFiltration’s portfolio of products includes filters for pools, greenhouses, and agricultural nurseries where bacteria and parasites are also threats, in addition to clean water filters. The company’s revenue from some of these other products also enables it to keep the costs of its clean water filter low while scaling to provide affordable water to those most in need.

The products have already been piloted in Ghana and are currently in use in Ecuador, Colombia, Peru, Fiji Islands, Cambodia, Vietnam, Ethiopia, Ghana, Kenya, Tanzania, and Nigeria.