The United States military has developed porous plastic bags coated in nanoclays that filter water. It works like this: The soldier behind enemy lines can drop the bag into any puddle, however dirty. Only clean water permeates the pouch via forward osmosis through the bag’s nanoclay coating. Most bacteria and viruses are filtered out including that for poliomyelitis, which is one of the smallest bacteria.
Pouches can contain dried food, which is rehydrated by the incoming clean water. Future versions will rehydrate food by taking in moisture from the air. All types minimize the weight that the soldier must carry. It could also be useful to hikers in remote regions, at least as emergency rations.
Smart packaging consultancy IDTechEx points out that such technology could be a lifesaver in underdeveloped countries, particularly after disasters. Indeed, the World Health Organisation estimates that 400 million children do not have access to potable water.
The developer of the pouch technology is www.hydrationtech.com, which currently charges about $40 for the self-filtering pouches. Several versions are available, including one that can be used ten times a day for ten days. Time for the aid agencies to move things forward?