FUNGAL COLONIZATION OF COMPUTER DISKETTES AND OTHER MAGNETIC MEDIA

Computer diskettes can be colonized by saprophytic fungi, especially i n the humid tropics. Fungi of the genera Alternaria, Aspergillus, Epic occum, Paecilomyces, Penicillium, and Trichoderma were observed on dis kettes from several tropical countries. Common saprophytic fungi from Minnesota colonized clean standard and high density diskettes in growt h chambers, indicating that fungal contamination could occur wherever temperature and humidity were adequate. Fusarium species infested disk ettes buried in garden soil in Minnesota. Audiotapes, videotapes, and computer magnetic tapes chemically resemble diskettes and also can be colonized by fungi, as can photographic film. The Mylar core of these magnetic media did not support the growth of Penicillium glabrum, the most aggressive fungus in diskette inoculation studies. However, growt h of several fungal species was enhanced when the common plasticizer, lecithin, was added in powdered form to nutrient agar, suggesting that this ingredient of the diskettes may be metabolized by the fungi.