SALT LAKE CITY, Sept. 14, 2009 Space is not a fun place to get a stomach bug. To ensure drinking water is adequately disinfected, University of Utah chemists developed a two-minute water quality monitoring method that just started six months of tests aboard the International Space Station.
"Now they bring water back on the space shuttle and analyze it on the ground. The problem is there is a big delay. You'd like to be able to maintain iodine or silver [disinfectant] levels in real time with an onboard monitor," says Marc Porter, a University of Utah professor of chemistry and chemical engineering.
The new method involves sampling space station or space shuttle galley water with syringes, forcing the water through a chemical-imbued disk-shaped membrane, and then reading the color of the membrane with a commercially available, handheld color sensor normally used to measure the color and glossiness of automobile paint.
The sensor detects if the drinking water contains enough iodine (used on U.S. spacecraft) or silver (used by the Russians) to kill any microbes. The International Space Station has both kinds of water purification systems.
"Our focus was to develop a small, simple, low-cost testing system that uses a handheld device, doesn't consume materials or generate waste, takes minimal astronaut time, is safe and works in microgravity," says Porter.
As a spinoff, the test is being modified so it can quickly check water for the level of arsenic a natural pollutant in places like Bangladesh and the U.S. Southwest and Northeast and it can be adapted to quickly, inexpensively test for other pollutants.
"It is a general method," says Lorraine Siperko, a senior research scientist in Porter's laboratory. "It could be used on the ground for testing all kinds of water contaminants such as arsenic, chromium, cadmium, nickel and other heavy metals."
The method is easy to use and much cheaper t
|Contact: Lee Siegel|
University of Utah