title: Profile and Morphology of Fungal Aerosols Characterized by Field Emission Scanning Electron Microscopy (FESEM).
abstract: Fungal aerosols consist of spores and fragments with diverse array of morphologies; however, the size, shape, and origin of the constituents require further characterization. In this study, we characterize the profile of aerosols generated fromAspergillus fumigatus, A. versicolor, andPenicillium chrysogenumgrown for 8 weeks on gypsum boards. Fungal particles were aerosolized at 12 and 20 L min-1using the Fungal Spore Source Strength Tester (FSSST) and the Stami particle generator (SPG). Collected particles were analyzed with field emission scanning electron microscopy (FESEM). We observed spore particle fraction consisting of single spores and spore aggregates in four size categories, and a fragment fraction that contained submicronic fragments and three size categories of larger fragments. Single spores dominated the aerosols fromA. fumigatus(median: 53%), while the submicronic fragment fraction was the highest in the aerosols collected fromA. versicolor(median: 34%) andP. chrysogenum(median: 31%). Morphological characteristics showed near spherical particles that were only single spores, oblong particles that comprise some spore aggregates and fragments (<3.5μm), and fiber-like particles that regroup chained spore aggregates and fragments (>3.5μm). Further, the near spherical particles dominated the aerosols fromA. fumigatus(median: 53%), while oblong particles were dominant in the aerosols fromA. versicolor(68%) andP. chrysogenum(55%). Fiber-like particles represented 21% and 24% of the aerosols fromA. versicolorandP. chrysogenum, respectively. This study shows that fungal particles of various size, shape, and origin are aerosolized, and supports the need to include a broader range of particle types in fungal exposure assessment.
authors: National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway.
authors: Komlavi Anani
authors: KA
authors: Afanou
authors: National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway.
authors: Anne
authors: A
authors: Straumfors
authors: National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway.
authors: Asbjørn
authors: A
authors: Skogstad
authors: Norwegian Veterinary Institute, Section of Mycology, Oslo, Norway.
authors: Ida
authors: I
authors: Skaar
authors: Norwegian University of Life Science, Institute of Chemistry, Biotechnology and Food Science, Ås, Norway.
authors: Linda
authors: L
authors: Hjeljord
authors: National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway.
authors: Øivind
authors: Ø
authors: Skare
authors: National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Allergy and Clinical Immunology Branch, Health Effect Laboratory Division, Morgantown, West Virginia, USA.
authors: Brett James
authors: BJ
authors: Green
authors: Norwegian University of Life Science, Institute of Chemistry, Biotechnology and Food Science, Ås, Norway.
authors: Arne
authors: A
authors: Tronsmo
authors: National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway.
authors: Wijnand
authors: W
authors: Eduard