Breakthrough: Universal detection system
just as fast and sensitive have higher false alarm rates.”
In lab experiments, SPAMS was tested against four types of materials terrorists might use — spores of a non-pathogenic strain of Bacillus anthracis (other strains of this bacteria cause anthrax); diethyl phthalate (a nerve agent surrogate), natural cobalt powder (a surrogate for Cobalt 60 and other radioactive metals) and trinitro-1,3,5-triazinane (RDX, a high explosive). Additionally, it was tested against pseudoephedrine (used to synthesize methamphetamine). In single- and multiple-agent tests, SPAMS accurately identified each substance and set off the correct alarms within an average of 34 seconds after their release against a background of air as the system was open to the environment. All of the measurements were achieved within 26 to 46 seconds after the compounds’ release. The two multiple-agent tests involved the use of natural cobalt powder and RDX, and a non-pathogenic strain of Bacillus anthracis and RDX. In field experiments, SPAMS has been tested at San Francisco International Airport. As part of a background study, the mass spectrometry system analyzed the air for about seven weeks in 2004-5, recording data, though it lacked the capability to set off alarms. The system records were later analyzed in the lab to evaluate whether any alarms, false or real, would have been triggered.
The researchers determined that while a few particles showed up as spores among the almost one million particles studied, there were so few that no alarms would have been triggered. “What distinguishes SPAMS from other instruments is the high-quality information we receive from the instrument in the form of single-particle mass spectra,” Frank said. “As a result, we get specificity and many fewer false alarms. We’re very enthusiastic about how the system is working, not only in the lab but also in field tests.” For the future, the Livermore team would like to develop ways to make the SPAMS machine smaller and less expensive. They would like to find opportunities for additional field tests, such as at airports, where SPAMS could be used to screen checked and carry-on baggage and at passenger portals. The instrument also could assist in screening people for disease and might help law enforcement authorities in examining suspicious powder samples.
Research funds to develop or field test SPAMS have been provided by the Defense Advanced Research Projects Agency and the Technical Support Working Group, both within the U.S. Department of Defense, as well as DHS. SPAMS started out almost a decade ago as an internally funded project at LLNL headed by Matthias Frank and Eric Gard. It originally only detected biological materials and was called the Bioaerosol Mass Spectrometry (BAMS) system. As the system gained new capabilities, it was renamed as SPAMS. Besides Frank and Steele, other researchers on the SPAMS team include chemists Eric Gard, David Fergenson, Keith Coffee, and George Farquar; forensic chemist and graduate student Audrey Martin; microbiologist Sue Martin; and electronics engineer Vincent Riot.
