Design and Performance of a Novel Personal Nasal Sampler (PNS) for Measuring Personal Exposure to Biological Aerosols

TAEWON HAN, Gediminas Mainelis, Rutgers, The State University of New Jersey

     Abstract Number: 189
     Working Group: Aerosol Exposure

Abstract
Accurate evaluation of personal exposure to biological aerosols is a significant challenge in bioaerosol science. We developed a personal nasal sampler (PNS) that attaches to a user's nostrils and utilizes their breathing to capture bioaerosols onto a hybrid filter, thus directly measuring actual personal exposure to airborne biological agents. The hybrid filter was designed by overlaying electrospun nanofibers of polyvinylidene fluoride (PVDF or P(VDF-TrFE) polymer onto a pulmonary test filter. This filter design showed an overall collection efficiency of over 90% for particles ranging from 10 nm to 10 µm, while maintaining a pressure drop < 300 Pa, in compliance with NIOSH guidelines. The filter also showed an 80% collection efficiency at a 10 L/min flow rate when tested with the Phi6 virus. The PNS was tested against the Button sampler for the ability to collect NaCl aerosols in the newly constructed walk-in chamber. The PNS samplers were mounted inside the nostrils of a manikin’s head and connected to personal pumps, while two Button samplers were placed in a manikin’s “breathing zone”. Each PNS was operated at 5 L/min. After 1 hour of sampling, the NaCl particles collected by all samplers were eluted into 10 mL of water, and their concentrations were compared. The latest PNS version demonstrated collection efficiency of approximately 79% when the Button samplers were equipped with 0.3 µm pore size filters; however, PNS captured 2- 3 times higher NaCl aerosol mass when the Button samplers were equipped with 1 and 2 µm pore size filters, indicating its superior performance in capturing small particles. Ongoing experiments test the PNS performance with different bacteria, viruses, and mold spores. Overall, the PNS concept demonstrates an effective new tool to estimate actual personal exposures to biological aerosols.