AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Passive Deposition Following Reaerosolization of Bacillus Spores from Urban and Operationally Relevant Surfaces
KAREN PONGRANCE, Jana Kesavan, Jason Edmonds, Deborah Schepers, Jerold Bottiger, Donna Carlile, Dan Vanreenen, US ARMY ECBC
Abstract Number: 659 Working Group: Aerosol Exposure
Abstract The potential for Bacillus in outdoor environments to resuspend or reaerosolize following an initial biological agent release is of concern because of its stability and potential for use as a biological weapon. A quantitative understanding of reaerosolization off of different surfaces is needed in order to make an assessment of the associated public health risks to secondarily exposed individuals if an event were to occur. The purpose of this study was to assess the potential biological hazard associated with wind driven reaerosolization off of contaminated surfaces commonly found in urban and military environments. The surfaces used in this study were vinyl floor tiles, brick, sod, concrete, gravel and CARC. In our study, we seeded Bacillus thuringiensis var. kurstaki dry spores onto these six surfaces in an ambient breeze tunnel, and then reaerosolized the organisms using a bank of fans which created a wind speed of 3.8 m/s over the seeded surface. Reaerosolized spores were recovered from floor tiles placed every ten feet up to a total distance of 100 feet from the initial point of deposition and were analyzed by culturing. Our results show that the settling deposition of reaerosolized Bacillus spores is dependent on the surface that the spores are reaerosolized off of, and that the quantity of Bacillus spores recovered down the length of the breeze tunnel was inversely correlated with distance from the seeded surfaces for all materials tested.