10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Quantitative Filter Forensics to Assess Indoor Exposures

Raheleh Givehchi, Juan Pedro Maestre, Chenyang Bi, Kerry Kinney, Ying Xu, Dennis Wylie, Sharon Horner, JEFFREY SIEGEL, University of Toronto

     Abstract Number: 1631
     Working Group: Indoor Aerosols

Abstract
The aim of this study is to assess the integrated average indoor airborne concentrations of particle-bound contaminants from dust extracted from heating, ventilation, and air conditioning (HVAC) filters by employing a novel quantitative filter forensics (QFF) approach. QFF allows for the estimate of integrated airborne concentrations of concentrations over the duration that the filter was installed and thus has potential to be a useful method to assess indoor airborne exposures. We extracted the dust from HVAC filters in 60 homes located in central Texas, USA. Filters were collected after one month of deployment in both summer and winter. Dust recovered from these filters were characterized for particle-bound contaminants including total fungal and bacterial DNA (using qPCR with generic primers), 36 common fungi species (with qPCR and species-specific primers), endotoxins, and semi-volatile organic compounds (SVOCs). When combined with HVAC system characterizations including system runtime, air flow rate, and filtration efficiency, we calculated the average airborne concentrations of each analyte in the homes in both seasons. The results showed considerable differences between the concentrations of airborne particle-bound contaminants between homes and it is not clear if short-term tests would capture these differences. In general, no statistical differences were observed for concentrations of contaminants between winter and summer. In this sample of homes, the HVAC measurements varied much less between homes than the dust concentration measurements, suggesting that even in the absence of HVAC data analyzing the dust on filters can provide insight about exposures about a relatively homogenous group of buildings. This study confirms the feasibility of the QFF approach to estimate airborne concentrations for a variety of particle-bound contaminants.