Diversity and seasonal dynamics of culturable airborne fungi in a cultural heritage conservation facility

An extensive aeromycological survey was performed in the premises of a cultural heritage conservation facility to estimate fungal propagule concentrations in both indoor and outdoor air and seasonal dynamics with regard to temperature and air humidity. The highest average propagule concentration in indoor air was documented in spring, and for outdoor air, in summer. Increased propagule loads were documented in most rooms during winter, fall and spring, and in all examined rooms in summer. Very high propagule concentrations (>25,000 CFU m−3) were reported in ground-floor rooms. The total mycobiota was comprised of 74 fungal species, with a prevalence of Aspergilli and Penicillia. Cladosporium and Penicillium isolates were found to be the most abundant in all seasons in both indoor and outdoor air samples. Among the identified fungi, potential human pathogens, allergens and mycotoxin producers were present. Numerous documented species play an important role in the deterioration of cultural heritage artifacts and are known producers of extracellular enzymes, acids and pigments. Application of a selective medium (M40Y) allowed isolation of various xerophiles and xerotolerant species. Aeromycological analyses are mandatory for determining the appropriate conditions for the protection of the health of conservators, as well as the objects of cultural heritage.