| Abstrakt: |
Bioaerosols consist of airborne particles such as microbes and debris from biological matter, present in the atmosphere. The interest in bioaerosols is increasing rapidly to broaden the knowledge of their characterization, and to understand how the bioaerosol affects environment and human health in both indoor and outdoor air. The experiments conducted inside confined artificial environments can provide valuable information on bioaerosol. At ChAMBRe (Chamber for Aerosol Modelling and Bioaerosol Research), managed by INFN at the Physics Department of the University of Genoa, Italy, the research on bioaerosol is focused on the investigation of the airborne bacteria behavior in different atmospheric conditions (Massabò et al., AMT, 2018). Our experiments were performed with Escherichia Coli, a gram-negative strain: the experimental protocol includes bacteria cultivation, bacteria injection in the chamber, exposure to different environmental conditions, and verification of viability (Danelli et al., 2021). The bacteria survival rate is evaluated in "clean air" conditions by comparing the bacteria total concentrations (measures by WIBS-NEO counter) with the Colonies Forming Units (CFU) collected on Petri dishes by Andersen impactor. The injected bacteria total concentration was about 0.40 cell cm-3, while the injected bacteria viable concentration was about 0.06 CFU cm-3. Since the time-trends of total and viable concentration differ significantly, as shown in Fig. 1, the resulting ratio between viable and total bacteria concentration was the observed parameter (Fig. 2). The viable-bacteria life-time turned out to be around 40 minutes. [ABSTRACT FROM AUTHOR] |
