Study on fungi in archives of offices, with a particular focus on Stachybotrys chartarum

Abstract

This study aimed at evaluating fungi in archives of different offices in Sari city the capital of Mazandaran, a northern province of Iran, with a particular focus on Stachybotrys chartarum. The samples were collected from twenty archives of offices and controls (n=7) using a SKC single-stage impactor which draws air at 20L/min (100L) and impacts the sampled material onto Petri dishes containing malt extract agar (MEA) (n=22) and also cellulose agar (CA) (n=22). Surface samples were also collected by pressing a sterile cotton swab on different areas of archives and cultured on MEA and CA. The grown fungi were identified by standard mycological techniques. The counted fungal colonies were converted to CFUs per cubic meter. In indoor air of archives, Cladosporium spp (25.1%), Aspergillus spp (22.9%) and Penicillium spp (22.9%) had the most frequencies. Stachybotrys chartarum (7.9%) was the fourth most common fungus isolated from the surface samples. Cladosporium spp had the highest total CFU concentration in indoor air of archive samples (1227/m(3)). Stachybotrys chartarum was recovered from surface collected samples of 4 archives of offices on CA. Out of the 22 rooms of archives, 45.4%, 45.4% and 9.1% had concentration level < 170 CFU/m(3), > 170 < 560 CFU/m(3) and > 560 < 1000 CFU/m(3), respectively. The results of our study have shown the high concentration levels of airborne fungi in some archives of offices that might put the workers at risk from respiratory diseases.