Bioaerosols are airborne particles of biological origin including viruses, bacteria, pollen, fungi, and fragments of their metabolic products. Bioaerosol exposure may represent a health risk, in particular for risk groups such as immunosuppressed persons, and those suffering from allergies or respiratory diseases. Bioaerosols of sizes
This study seeks to assess outdoor bioaerosol number concentrations and size distributions in Las Vegas, NV, as the first step in understanding their health risks. PM2.5 and PM10 were collected on black polycarbonate filters for 24-hour duration using MiniVol air samplers on UNLV campus in the spring and fall of 2017. Bioaerosols in these samples were counted by a direct-stain fluorescence microscopic (DS-FM) method. The size of each particle was also measured, on a daily basis, from which the bioaerosol number concentrations, were determined. DS-FM results were analyzed by statistical methods to examine if there were significant differences between spring and fall with respect to bioaerosol number concentration and size distribution. The samples were also classified by wind conditions to explain the day-to- day variability.
A significant difference was found between the means of bioaerosol concentrations during spring and fall for both PM2.5 and PM10. Bioaerosols of 1 - 2.5 μm diameter were found to be the most common and peaked in PM10 samples collected during the fall. Windier conditions corresponded to higher concentrations of bioaerosols for both PM10 and PM2.5.This study could be a catalyst for further research on the bioaerosol-public health linkage, which would help refine the National Ambient Air Quality Standards to reduce adverse health outcomes
