AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Assessing Building Penetration Challenges by Subalpine Wildfires: Juxtaposing Airborne Biomarker Profiles with Microbial Community Analysis
ALINA M. HANDOREAN, Bharath Prithiviraj, Odessa Gomez, Jane Turner, Mark T. Hernandez, University of Colorado Boulder
Abstract Number: 271 Working Group: Indoor Aerosols
Abstract Wildfires are becoming more frequent in temperate regions, as is their proximity to (sub)urban building complexes. Profiles of biochemical and genetic biomarkers were assessed for their ability to serve as selective penetration indicators when buildings were challenged with aerosols generated by a sub-alpine wildfire. This profile included airborne carbohydrates, phospholipids and phylogenetic profiles of microbes associating with airborne particulate matter.
Twenty-four hour, size segregated composite samples were collected indoors and outdoors of a building complex before and during a wildfire event and compared with baselines collected from a similar environment not impacted by wildfire. Carbohydrate content was measured using a colorimetric assay of monosaccharide phenol conjugates, with glucose as a standard. Phospholipid content was measured using a colorimetric assay of chloroform-methanol extracts subjected to persulfate digestion, and calibrated against a ß-glycerol phosphate standard.
Genomic DNA was extracted and PCR amplicons were generated using 515F / 806 R primers specific to the V4 region of 16S rRNA. These primers amplified Archaeal and Bacterial hypervariable 16S regions and amplicons were barcode tagged with linker sequences. Paired end Illumina reads were obtained from the sequencing run. Data was analyzed using the Quantitative Insights Into Microbial Ecology (QIIME) and taxonomic structure, alpha (within site) and beta (between site) diversity were derived using the Unifrac phylogenetic diversity metric. Microbial heat maps were constructed indicating intensity of aerosol loads and statistical correlation established with biopolymer loads. Metagenomic gene content was analyzed using PICRUSt based on copy number of 16S bioaerosols. This enabled assessment of metabolic potential for fire generated bioaerosols, and its influence on the indoor environment as the fire progressed. While more abundant in the outdoor samples, patterns of biopolymer contribution to indoor and outdoor organic carbon loads, suggest building penetration mode which could not be elucidated by conventional PM analysis.