Testing Bio-Agents in the Open-Air Shows Surprising Results

Courtesy Photo | Chambers of the Captive Aerosol Growth and Evolution System (CAGES) at the Albuquerque, New Mexico, test site. Through CAGES, scientists examine how simulants of biological threat agents decay upon interacting with variables in the open air. Photo courtesy of Sandia National Laboratory.  

FORT BELVOIR, VIRGINIA, UNITED STATES

01.28.2021

Courtesy Story

Defense Threat Reduction Agency

By Defense Threat Reduction Agency Public Affairs


FORT BELVOIR, Va. — The Defense Threat Reduction Agency’s Chemical and Biological Technologies Department (DTRA CB) recently invested in research that resulted in a dramatic improvement on understanding how biological agents degrade outdoors.

The experiments revealed that in open air, simulants decayed 10 to 1,000 times faster than in laboratory settings. These data indicate that laboratory tests underestimate the rate of agent decay that occurs outdoors, and on their own, laboratory tests are not sufficient in understanding the decay process outdoors.

“Due to various challenges posed by outdoor testing, it was generally assumed by scientists that biological threat agents aged and decayed at similar rates indoors as they did outdoors. Our goal was to test this theory,” said Richard Mathieson, Science & Technology Manager, DTRA CB.

To learn how biological threat agents decay upon interacting with variables in the open air, DTRA CB developed a new, state-of-the-art test apparatus, the Captive Aerosol Growth and Evolution System (CAGES).

“We have a great deal of data about bio threat degradation testing from laboratory settings,” said Mathieson. “What we don’t have is results of testing in the natural environment. For obvious reasons, it is difficult to test live biological threat agents outdoors.”

“With CAGES, we received more accurate outdoor agent decay data. This level of accuracy to real-world situations was not possible before,” said Mathieson.

The research was performed at the Sandia National Laboratory, National Strategic Research Institute, and the Army Research Laboratory. Researchers evaluated the combination of open-air factors that most affect the rate of agent decay. They also compared data collected in laboratory studies to data collected in outdoor experiments.

“It can often take the support of a number of contributing organizations to accomplish a multisite effort like this one. This approach tends to offer the opportunity to be thorough in our studies and get the research right,” Mathieson said.

The experiment took place in two locations: Albuquerque, New Mexico, and Houston, Texas. According to the Environmental Protection Agency, “Pollutants are emitted by a variety of sources and concentrations can vary by region.” Houston, for example, has oil refineries, so it has many more air pollutants than Albuquerque does.

The differing air quality in the two cities offers differing pollutant levels that can interact with aerosolized biological agents. In both cities, researchers quantified how components of the atmosphere would affect an agent’s makeup and response.

Outdoors tests performed within the rotating drum chambers of CAGES contained simulants representing biological threat agents and would expose them to different atmospheric conditions and compositions. Afterwards, aerosol samples were taken from the chambers to study their physical and chemical properties. Meanwhile, laboratory tests were used to conduct indoor aerosol testing that mimicked real-world, aging conditions in the indoors to compare against the outdoor decay data.

“This CAGES project is just one example of how DTRA CB develops technologies and capabilities to protect warfighters and the nation from chemical and biological threats,” said Ron Hann, Ph.D., Director of DTRA CB.

Data gathered through these experiments may transform the way DTRA CB examines the aging and decay of biological threat agents in the future. Improved, fundamental knowledge of agent decay provides more accurate data to the modeling community, and ultimately, to the warfighter who needs to operate in a contaminated environment.

• Date Taken: 01.28.2021
• Date Posted: 01.28.2021 14:04
• Story ID: 387824
• Location: FORT BELVOIR, VIRGINIA, US