AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Improved Collection of Airborne Bacteria and Yeast through Water-based Size Amplification
MAOHUA PAN, Leah Carol, John Lednicky, Arantzazu Eiguren Fernandez, Susanne Hering, Hugh Fan, Chang-Yu Wu, University of Florida
Abstract Number: 348 Working Group: Bioaerosols
Abstract Inhalation of or exposure to airborne bacteria and fungi in the form of mycelium fragments, spores, or yeast, has been a great concern worldwide because of their association with numerous respiratory diseases and other health related impacts. One limitation for sampling these microorganisms is the deactivation of bacteria or yeast during the sampling process, due to the stresses from dehydration and/or impaction. In this study, lab generated bacteria (E. coli) and yeast (S. kudriavzevii) aerosol particles were collected by a laminar flow water-based condensational “growth tube collector (GTC)” and an industry-standard BioSampler. The GTC works by particle size-amplification through water vapor condensation and gentle deposition of the enlarged particles onto liquid collection media. In contrast, the BioSampler is an impinger that deposits collected particles into collection media in a more aggressive swirling motion. Comparison was made between the GTC and the BioSampler for the collection of vegetative bacteria and yeast using two collection media, PBS and nutrient media (NM). The GTC had equivalent performance to the BioSampler when PBS was used as the collection medium for E. coli, whereas 40% more bacteria were collected in the GTC than the BioSampler when NM was used. For S. kudriavzevii, the GTC had better performance for both PBS and the NM. The BioSampler rarely collected anything for air concentrations below 4´103 CFU/L, while the GTC collected yeast cells at a concentration as low as 4´102 CFU/L. These results indicate that the GTC is a promising device for sampling viable bacteria and fungus with a lower detection limit than the standard Biosampler.