Background and purpose: Dust storms can transfer particulate pollutants to long distances,
and in some cases, to thousands of kilometers from their source. These dust storms can carry very large
volumes of bioaerosols such as fungal species which are the causes of respiratory infections and allergies.
The aim of this study was to determine the impact of dust storms on transmission of fungal species in
atmospheric air of Ilam, Iran.
Materials and methods: For the purpose of study, the concentration of suspended particles in the
air of Ilam was measured during normal and dusty days for one year using the standard protocols.
Results: As the results indicated, the northern deserts of Iraq are responsible for most of the dust
storms in Ilam. The higher number of dust storms during the warm season increased the average
concentration of these particles within the first six months of the year. The PM2.5/PM10 ratios of the
ordinary and dusty days were 0.248 and 0.191, respectively, indicating natural origins of dust particles.
Results of Mann-Whitney non-parametric test demonstrated a significant difference between the dusty
and ordinary days regarding the fungal colonies (P<0.05). Accordingly, with increase in concentrations of
PM10 and PM2.5, the density of airborne fungal colonies rose. According to the Kruskal-Wallis test, the
concentrations of fungal colonies were significantly different during different months and seasons of the
year (P<0.05). In the present study, the most common fungal species were Cladosporium, Penicillium,
Aspergillus, and Alternaria.
Conclusion: The findings of the current study revealed that the ambient concentration of fungal
species is affected by dust concentration as the concentration of fungal species on dusty days was higher
than normal days.