Feasibility Study of BioTube: A Portable and Expandable Chamber for Passive Bioaerosol Sampling

JENNA MYERS, Gediminas Mainelis, Rutgers, The State University of New Jersey

     Abstract Number: 690
     Working Group: Bioaerosols

Abstract
Bioaerosols are suspended biological particles that include viruses, bacteria, mold, pollen, and their fragments and byproducts. Due to the adverse health effects they may trigger, active and passive sampling methods can determine bioaerosol presence and exposure in indoor and outdoor environments. Active sampling protocols are commonly utilized for bioaerosols due to their quantitative nature and relatively short sampling times, whereas passive samplers often have longer sampling times with less quantitative information. Previous studies examined the logistics of passive bioaerosol sampling with a settling chamber, also called a BioTube. Samples in this circumstance were collected onto agar plates confined within a nine-foot mailing tube via gravitational settling.

Due to the large dimensions of this settling chamber, the BioTube was redesigned. This study evaluated the practicality of a portable, collapsable BioTube in an outdoor environment and its collection effectiveness compared to an active sampler. Petri dishes filled with bacterial or fungal growth medium were placed inside five BioTubes adjacent to a one-stage Andersen cascade impactor to determine airborne bacterial and fungal concentrations. Each BioTube was hung upon deployment and then steadily expanded to pull ambient air in due to vacuum as the impactor ran simultaneously. Once the BioTube expanded to five feet in length, it was closed, and the captured microorganisms were allowed to settle overnight. Depending on the agar used, colonies grown on sampled plates were used to determine airborne concentration of culturable bacteria or mold. Average bacterial concentrations sampled by the BioTube and impactor were similar (265 CFU/m3 and 257 CFU/m3, respectively). In comparison, average fungal concentrations were more than two times greater in the impactor (6,209 CFU/m3) than in the BioTube (2,329 CFU/m3). Factoring in environmental conditions and convenience of use (e.g., no need for a pump), the collapsable BioTube shows promise as a low-impact bioaerosol sampling tool.