A new device slightly larger than a soda can could eliminate more than 90 percent of the weight from water that military medics carry or ship.
The MainStream water purifier is designed to filter out traces of bacteria, viruses and other toxins from any source of water by a series of filters and chemical reactions.
The device, which does not require electricity or battery power, is designed for use in areas where clean water for washing wounds or drinking is scarce. The device could also be used by medical crews responding to terrorist attacks and natural disasters.
The U.S. Army has ordered more than 5,000 MainStream Water Purification Devices, manufactured by Prismedical Corp. in Napa. The first shipments, sent for free by Prismedical, were sent to troops on the front lines in Iraq and Afghanistan.
The U.S. Food and Drug Administration gave Prismedical clearance to market the device in May 2002, and it is the only portable device approved to make sterile water for medical purposes. The company has applied for FDA approval to use the device more broadly.
A Mainstream purifier costs about $77 and is designed to be used only once. Each unit weighs 1.1 pounds and can convert 3 liters of contaminated water into clean water in about 30 minutes.
The contaminated water is poured into a plastic bag hung over the top of the device and connected to it by a plastic tube. The water then drips into the purifier and flows through three sets of filtering systems, which remove solid particles, organic and inorganic material and bacteria.
The sterilized water then flows into another bag hung below the unit. The filtering time can also be cut in half by having the patient lie on the top bag to push the water through faster.
Prismedical says tests showed the device can remove 10 million types of bacteria and 6 million viruses, while leaving less than 1.25 parts per million of solid particles and less than .25 parts per million of endotoxins.
The device works on fresh and brackish water, whether from the Napa River or the Tigris and Euphrates, Sizelove said. Prismedical is still working on a way of purifying salt water.
An FDA report issued in May 2002 said FDA tests showed the device was effective for producing water to rinse open wounds, clean medical equipment and wash the hands of medical personnel, as well as for use in drug preparation and other medical tasks requiring purified water.
Prismedical has also applied for FDA approval to sell the MainStream for the preparation of sterile saline solutions for intravenous treatments.
The MainStream can be a way of administering fluids to a trauma patient within the first hour of an injury, Sizelove said. "If not, the organs can degrade and shut down, so the ability to produce sterile purified water out in the middle of nowhere in less than an hour is critical to increasing patient outcomes," he said.
The MainStream can also help soldiers who are running low on water to replenish on the spot, he said, with water that doesn't have the unpleasant aftertaste of water produced by purification tablets.
Larger versions of the MainStream could also be useful in getting water to remote areas of developing nations, he said.