Measurement of personal exposure to outdoor aeromycota in northern New South Wales, Australia

Aerobiological sampling traditionally uses a volumetric spore trap located in a fixed position to estimate personal exposure to airborne fungi. In this study, the number and identity of fungi inhaled by human subjects (n=34), wearing Intra-nasal air samplers (INASs), was measured over 2-hour periods in an outdoor community setting, and compared to fungal counts made with a Burkard spore trap and Institute of Occupational Medicine personal filter air samplers (IOMs). All sampling devices were in close proximity and located in an outdoor environment in Casino, northern New South Wales, Australia. Using INASs, the most prevalent fungi inhaled belonged to soil or vegetation borne spores of Alternaria, Arthrinium, Bipolaris, Cladosporium, Curvularia, Epicoccum, Exserohilum, Fusarium, Pithomyces, Spegazzinia and Tetraploa species, Xylariaceae ascospores, in addition to hyphal fragments. These results showed that inhaled fungal exposure in most people varied in a 2-fold range with 10-fold outliers. In addition, the INASs and personal air filters agreed more with each other than with Burkard spore trap counts (r=0.74, p < 0.0001). These findings further support a new paradigm of personal fungal exposure, which implicates the inhalation of a spectrum of fungi more closely associated with soil or vegetation borne mycoflora and hyphal fragments than what is collected by stationary spore traps in the same geographic region.