Seasonal distribution pattern of outdoor airborne fungi in Basrah city, southern Iraq

Abstract

An assessment of air quality by examining outdoor airborne fungi among three sites over four seasons of the year 2009 in Basrah city (Iraq) was made. Gravitational setting method using Petri plates containing agar medium was applied. The results showed that nine fungal genera including 16 species besides the yeasts were prevalent in air samples. The most predominant fungi belonged to the genera Cladosporium, Penicillium, Alternaria and Aspergillus. Highest counts of the fungal isolates were recorded for C. cladosporioides (31.3 % frequency) followed by P. notatum (11.9 % frequency), A. alternata (10.0 % frequency) and Asp. niger (5.8 % frequency). A significant difference (P < 0.001) in the fungal populations over the four seasons was detected. Winter and summer exhibited higher fungal total isolates than spring and autumn at the studied sites. A correlation coefficient analysis revealed negative values between air temperature and total fungal counts and positive values between air humidity and fungal total counts over seasons. This study provided some information regarding the outdoor air borne fungal composition at Basrah city and suggesting a further investigation to correlate between the common human allergies among the population of Basrah and the high incidence of airborne fungi in outdoor environment of this city.