Airborne fungal and bacterial components in PM1 dust from biofuel plants

Fungi grown in pure cultures produce DNA- or RNA-containingparticles smaller than spore size (1.5 µm. The numberof cultivable fungi and ß-glucan in the total dust correlatedsignificantly with the number of DNA/RNA-containing particleswith lengths of between 1.0 and 1.5 µm, with DNA/RNA-containingparticles >1.5 µm, and with other fungal componentsin PM1 dust. Airborne ß-glucan and NAGase were found inPM1 samples where no cultivable fungi were present, and ß-glucanand NAGase were found in higher concentrations per fungal sporein PM1 dust than in total dust. This indicates that fungal particlessmaller than fungal spore size are present in the air at theplants. Furthermore, many bacteria, including actinomycetes,were present in PM1 dust. Only 0.2% of the bacteria in PM1 dustwere cultivable.