Getting a drink of water in rural sub-Saharan Africa or India can also mean getting sick. Around the world, water-related diseases end up killing 6 to 8 million people a year. A simple new water filter might help: Screw it onto a standard water bottle, squeeze, and you instantly have clean water.
Unlike old-school water purification tablets, which take up to 45 minutes to work, or the traditional method of boiling water, the DrinkPure filter provides safe drinking water immediately. It’s also faster than other types of water filters; a single minute-long squeeze can purify a full liter of water.
“The most unique part of the design is that we have a higher flux than other products–meaning you can get more water in the same amount of time through the filter,” says Jeremy Nussbaumer, a student at ETH Zurich, who helped develop the technology.
It’s essentially as simple to use as drinking straight from a bottle, in contrast to some similar devices like the LifeStraw, a straw-like filter that has been criticized as especially difficult for first-time users. The DrinkPure filter doesn’t really need instructions, which helps save money, since nonprofits with clean water technology often have to invest in marketing materials to make sure people are using the device correctly.
Once the filter is attached to the top of the bottle, it can stay in place for a year of use; when the filter starts slowing down, someone can replace it with a new one. The filter works in three steps: a “pre-filter” catches the biggest particles, like plant debris or dirt, then a layer of activated carbon traps chemicals, odors, and heavy metals, and then a polymer membrane, developed at ETH Zurich, filters out bacteria.
It’s designed to be an ultra-low cost solution, made from a fairly simple process that eventually could be replicated locally in the places where it’s needed. The team chose to make it compatible with plastic water bottles to make it even cheaper and to reduce transportation, since water bottles are already ubiquitous around the world.
Of course, most water bottle manufacturers actually don’t recommend reusing bottles, in part because the plastic tends to degrade over time and develop tiny cracks that can harbor bacteria if the bottle isn’t properly cleaned. But the filter, in theory, would protect someone from any bacteria inside. And if there’s any risk from something like BPA leaching out of the plastic, Nussbaumer argues it would be far overshadowed by the health benefits of using the filter.
The team is currently raising money on Indiegogo, and has already raised enough to set up large-scale manufacturing and bring the filters to five villages early next year.