Monitoring of toxinogenic producing fungi in air conditioning system dust at some clinics.

Eighty four samples out of 1260 isolates from; filter's dust, wing's dust, indoor air without air condition and indoor air with air condition (14 for each) were collected every month through four months in this study from 14 clinics in Damietta Governorate, North East of Egypt. Aeromycobiota were isolated by open plate and filtration techniques, while filter and wing dusts were isolated using dilution plate technique on Czapek’s Yeast Extract Agar, Potato Dextrose Agar, and Dichloran-Glycerol-18 Agar. Eight taxa belonging to five genera were recovered in dust during this survey: Aspergillus, Mucur, Fusarium, Penicillium and Alternaria. The dust accumulated fungi number of wing and filter dust (DAF) ranged from 120 to 1240 and 60 to 480 CFU/cm2, respectively. Indoor air of the clinics before and after turning on AC collected by open plate technique is contaminated with twelve fungal species from six genera. While that was collected by filtration technique is contaminated with nine fungal species from six genera. Results revealed that some isolated fungi had ability to produce Aflatoxins as A. flavus & A. parasiticus and Ochratoxin A as A. niger & A. ocraceus