Generation of Viable Bacterial and Fungal Aerosols during Biomass Combustion

Abstract

Biomass combustion is known to be one of the main contributors to air pollution. However, the influence of biomass burning on the distribution of viable bacterial and fungal aerosols is uncertain. This study aimed to examine survivability of bacteria and fungi in the post-combustion products, and to investigate the aerosolization of viable cells during combustion of different types of organic materials. Laboratory experiments included a small-scale combustion of organic materials contaminated with microorganisms in order to determine the survivability of microbes in the combustion products and the potential aerosolization of viable cells during combustion. Field experiments were completed during intentional and prescribed biomass burning events in order to investigate the aerosolization mechanisms that are not available at the laboratory scale. Laboratory experiments did not demonstrate aerosolization of microorganisms during biomass combustion. However, the relatively high survival rate of bacteria in the combustion products ought to be accounted for, as the surviving microorganisms can potentially be aerosolized by high velocity natural air flows. Field investigations demonstrated significant increase in the bioaerosol concentration above natural background during and after biomass combustion.

Limited Evidence for a Microbial Signal in Ground‐Level Smoke Plumes

“…The idea that microbes can be aerosolized and are detectable in wildfire smoke plumes is derived from multiple lines of evidence. First, smoke captured from the burning of vegetation in laboratory settings and in tobacco smoke have previously been shown to contain viable bacteria and fungi (Larsson et al., 2008; Malayil et al., 2022; Mirskaya & Agranovski, 2020; Pauly & Paszkiewicz, 2011). Likewise, the air inside homes where biomass fuels are used for cooking and heating have been found to contain higher concentrations of bacterial endotoxins (Akila et al., 2020).…”