Friday, April 2, 2010

Technologies Underlying Weapons of Mass Destruction/Office of Technology Assessment

In 1993 the US Government knew that silicon was used to enhance dispersal of powdered microbial agents and toxins.  OTA produced some very useful research, but the agency no longer exists.

U.S. Congress, Office of Technology Assessment, Technologies Underlying Weapons of Mass Destruction, OTA-BP-ISC-115 (Washington, DC: U.S. Government Printing Office, December 1993).
The stability of a microbial aerosol can be
increased by adding a variety of compounds to the
spray material.58 Moreover, antiagglomerants such
as colloidal silica help prevent the clumping of
freeze-dried microbial agents and toxins that have
been milled into a fine powder.

1 comment:

DXer said...

The 1993 report by the Office of Technological Assessment “Technologies Underlying Weapons of Mass Destruction” continues:

"Agricultural research on biological pesticides, such as the insect-killing bacterium Bacillus thuringiensis, has provided much information on methods for stabilizing bacterial agents in the field. For example, new formulations of B. thuringiensis have been developed that extend the life of the disseminated bacteria by means of ultraviolet protestants and other additives that ensure compatibility with existing agricultural sprayers.

[citing "Viability and Infectivity of Microorganisms in Experimental Airborne Infection," Bacteriological Reviews, vol 25. 1961, p. 185.]


Another approach to stabilization, known as microencapsulation, emulates natural spore formation by coating droplets of pathogens or particles of toxin with a thin coat of gelatin, sodium alginate, cellulose, or some other protective material. (An industrial example of microencapsulation is the production of carbonless carbon paper, in which ink droplets are coated in this manner. Microencapsulation can be performed with physical or chemical methods. (citation omitted)

Microencapsulation production methods can be set up to generate particles of a selected size range (e.g., 5 to 10 microns). The polymer coating protects the infectious agent against environmental stresses such as desiccation, sunlight, freezing, and the mechanical stresses of dissemination, and permits cold-storage of microbial pathogens for several months.” Microcapsules can be charged electrostatically to reduce particle clumping during dissemination, or ultraviolet blocking pigments can be added to the microcapsule to protect microorganisms against degradation by sunlight. Once in the target environment, such as the interior of the lung, the polymer coating dissolves, releasing the agent. Microencapsulation can also be applied to toxins, making them more stable, predictable, and safer to handle.”