Bacteria and fungi in organic dust as potential health hazard

People engaged in agriculture, waste collection and other professions are exposed to large quantities of bioaerosols associated with organic dusts, ranging from 10-10 cfu/m. These bioaerosols are composed of Gram-negative rod-shaped bacteria, Gram-positive, non-branching bacteria (corynebacteria, cocci and endospore-forming bacilli), actinomycetes and fungi (moulds and yeasts). Endotoxin produced by Gramnegative bacteria causes non-specific, inflammatory reaction in the lungs of exposed people, while thermophilic actinomycetes and moulds are a common cause of allergy. So far only little is known about health effects of Gram-positive bacteria, which in many cases form a dominant fraction of dust-borne bioaerosols. Address for correspondence: Jacek Dutkiewicz, Department of Aerobiology and Allergology, Institute of Agricultural Medicine, P.O.Box 185, 20-950 Lublin, Poland. E-mail: dutkiewi@galen.imw.lublin.pl