AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Further Investigation and Application of Passive and Low-Energy Bioaerosol Samplers
SYDONIA MANIBUSAN, Gediminas Mainelis, Rutgers, The State University of New Jersey
Abstract Number: 289 Working Group: Bioaerosols
Abstract The Rutgers Electrostatic Passive Sampler (REPS) is a passive bioaerosol sampler that captures particles due to electrostatic fields created by permanently polarized polyvinylidene fluoride (PVDF) film. It was shown to perform comparably to active samplers in outdoor environments, with equivalent flow rates of 2.6 L/min and higher for culturable bacteria. However, initial tests found poorer performance indoors. We hypothesized that this difference in sampler performance was due to less vigorous air movement indoors than in the outdoor environment, where stronger air currents bring particles closer to REPS to be captured by passive means. This hypothesis was tested in a residence, where an air circulator fan operating about 2.5 m away from the sampler provided wind speeds of ~0.6 m/s at the sampler’s location. In a separate test, REPS was integrated with a low-power pump (REPS-Active) operating at 0.1-0.5 L/min (0.0034-0.017 m/s air velocity through REPS) to further investigate the effect of air movement on particles captured by REPS. Samplers were operated for 24-72 hours. Reference concentrations were provided by a SAS Super 180 (Bioscience International, Rockville, MD). We found that for culturable bacteria, REPS had an equivalent sampling flow rate of ~ 2 L/min with introduced air circulation, while the equivalent flow rates with natural ventilation alone were ~ 1 L/min. Concentrations of culturable bacteria determined by SAS were ~420 CFU/m3, while those determined by the REPS-Active were above 1,500 CFU/m3. The results suggest that for indoor investigations, REPS should be placed near an air mixing source, e.g., a ventilation duct or fan to enhance microorganism capture. In addition, REPS-active shows a great promise as a low-power sampler capable of preserving microorganism culturability over long-term sampling which would allow quantifying long-term bioaerosol exposures. The findings will be verified by experiments in different air environments.