Gamma camera could detect nuclear waste threat
Gamma-camera imaging can provide real-time information on the mobility of technetium and was used to confirm that Fe(III)-reducing bacteria immobilized technetium in sediments, based on research published in the January issue of Environmental Science and Technology.

Lead investigator Jonathan R. Lloyd, PhD, from the School of Earth, Atmospheric and Environmental Science at the University of Manchester, U.K., and colleagues analyzed soil samples from the Oak Ridge National Laboratory, a nuclear facility in the Oak Ridge, Tenn., and tracked the movement of technetium through the soil.

Researchers found that Fe(III)-reducing bacteria can fix technetium in soils and used gamma camera to probe how technetium and ferric iron move together in far more complex soil systems.

"Using this medical scanning technique we were able to explore, in real time, the mobility of one of the most problematic and mobile radionuclides in sediments,” said Lloyd. “Our success will allow scientists to accurately monitor the success of new biological methods in trapping radioactive elements in sediments and stopping them spreading further into the natural environment."

The authors wrote that the combination of approaches afforded by gamma-camera imaging are currently underused, but offer a potentially valuable, noninvasive tool for imaging ultratrace pollutant mobility in sediments.